Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 484
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Mol Cell ; 79(2): 234-250.e9, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32579944

RESUMO

Somatic cell nuclear transfer (SCNT) can reprogram a somatic nucleus to a totipotent state. However, the re-organization of 3D chromatin structure in this process remains poorly understood. Using low-input Hi-C, we revealed that, during SCNT, the transferred nucleus first enters a mitotic-like state (premature chromatin condensation). Unlike fertilized embryos, SCNT embryos show stronger topologically associating domains (TADs) at the 1-cell stage. TADs become weaker at the 2-cell stage, followed by gradual consolidation. Compartments A/B are markedly weak in 1-cell SCNT embryos and become increasingly strengthened afterward. By the 8-cell stage, somatic chromatin architecture is largely reset to embryonic patterns. Unexpectedly, we found cohesin represses minor zygotic genome activation (ZGA) genes (2-cell-specific genes) in pluripotent and differentiated cells, and pre-depleting cohesin in donor cells facilitates minor ZGA and SCNT. These data reveal multi-step reprogramming of 3D chromatin architecture during SCNT and support dual roles of cohesin in TAD formation and minor ZGA repression.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Cromatina/fisiologia , Proteínas Cromossômicas não Histona/fisiologia , Técnicas de Transferência Nuclear , Zigoto/fisiologia , Animais , Linhagem Celular , Núcleo Celular , Montagem e Desmontagem da Cromatina , Biologia Computacional/métodos , Conjuntos de Dados como Assunto , Desenvolvimento Embrionário , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coesinas
2.
BMC Genomics ; 25(1): 492, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760719

RESUMO

Rapeseed (Brassica napus L.), accounts for nearly 16% of vegetable oil, is the world's second produced oilseed. However, pod shattering has caused significant yield loses in rapeseed production, particularly during mechanical harvesting. The GH28 genes can promote pod shattering by changing the structure of the pod cell wall in Arabidopsis. However, the role of the GH28 gene family in rapeseed was largely unknown. Therefore, a genome-wide comprehensive analysis was conducted to classify the role of GH28 gene family on rapeseed pod shattering. A total of 37 BnaGH28 genes in the rapeseed genome were identified. These BnaGH28s can be divided into five groups (Group A-E), based on phylogenetic and synteny analysis. Protein property, gene structure, conserved motif, cis-acting element, and gene expression profile of BnaGH28 genes in the same group were similar. Specially, the expression level of genes in group A-D was gradually decreased, but increased in group E with the development of silique. Among eleven higher expressed genes in group E, two BnaGH28 genes (BnaA07T0199500ZS and BnaC06T0206500ZS) were significantly regulated by IAA or GA treatment. And the significant effects of BnaA07T0199500ZS variation on pod shattering resistance were also demonstrated in present study. These results could open a new window for insight into the role of BnaGH28 genes on pod shattering resistance in rapeseed.


Assuntos
Brassica napus , Filogenia , Proteínas de Plantas , Brassica napus/genética , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Genoma de Planta , Sintenia , Perfilação da Expressão Gênica
3.
BMC Med ; 22(1): 4, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166913

RESUMO

BACKGROUND: We aimed to determine whether and how the combination of acetazolamide and remote ischemic preconditioning (RIPC) reduced the incidence and severity of acute mountain sickness (AMS). METHODS: This is a prospective, randomized, open-label, blinded endpoint (PROBE) study involving 250 healthy volunteers. Participants were randomized (1:1:1:1:1) to following five groups: Ripc (RIPC twice daily, 6 days), Rapid-Ripc (RIPC four times daily, 3 days), Acetazolamide (twice daily, 2 days), Combined (Acetazolamide plus Rapid-Ripc), and Control group. After interventions, participants entered a normobaric hypoxic chamber (equivalent to 4000 m) and stayed for 6 h. The primary outcomes included the incidence and severity of AMS, and SpO2 after hypoxic exposure. Secondary outcomes included systolic and diastolic blood pressure, and heart rate after hypoxic exposure. The mechanisms of the combined regime were investigated through exploratory outcomes, including analysis of venous blood gas, complete blood count, human cytokine antibody array, ELISA validation for PDGF-AB, and detection of PDGF gene polymorphisms. RESULTS: The combination of acetazolamide and RIPC exhibited powerful efficacy in preventing AMS, reducing the incidence of AMS from 26.0 to 6.0% (Combined vs Control: RR 0.23, 95% CI 0.07-0.70, P = 0.006), without significantly increasing the incidence of adverse reactions. Combined group also showed the lowest AMS score (0.92 ± 1.10). Mechanistically, acetazolamide induced a mild metabolic acidosis (pH 7.30 ~ 7.31; HCO3- 18.1 ~ 20.8 mmol/L) and improved SpO2 (89 ~ 91%) following hypoxic exposure. Additionally, thirty differentially expressed proteins (DEPs) related to immune-inflammatory process were identified after hypoxia, among which PDGF-AB was involved. Further validation of PDGF-AB in all individuals showed that both acetazolamide and RIPC downregulated PDGF-AB before hypoxic exposure, suggesting a possible protective mechanism. Furthermore, genetic analyses demonstrated that individuals carrying the PDGFA rs2070958 C allele, rs9690350 G allele, or rs1800814 G allele did not display a decrease in PDGF-AB levels after interventions, and were associated with a higher risk of AMS. CONCLUSIONS: The combination of acetazolamide and RIPC exerts a powerful anti-hypoxic effect and represents an innovative and promising strategy for rapid ascent to high altitudes. Acetazolamide improves oxygen saturation. RIPC further aids acetazolamide, which synergistically regulates PDGF-AB, potentially involved in the pathogenesis of AMS. TRIAL REGISTRATION: ClinicalTrials.gov NCT05023941.


Assuntos
Doença da Altitude , Precondicionamento Isquêmico , Humanos , Doença da Altitude/prevenção & controle , Doença da Altitude/diagnóstico , Acetazolamida , Estudos Prospectivos , Doença Aguda , Hipóxia/prevenção & controle
4.
Glob Chang Biol ; 30(3): e17234, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38469998

RESUMO

Rapid biodiversity losses under global climate change threaten forest ecosystem functions. However, our understanding of the patterns and drivers of multiple ecosystem functions across biodiversity gradients remains equivocal. To address this important knowledge gap, we measured simultaneous responses of multiple ecosystem functions (nutrient cycling, soil carbon stocks, organic matter decomposition, plant productivity) to a tree species richness gradient of 1, 4, 8, 16, and 32 species in a young subtropical forest. We found that tree species richness had negligible effects on nutrient cycling, organic matter decomposition, and plant productivity, but soil carbon stocks and ecosystem multifunctionality significantly increased with tree species richness. Linear mixed-effect models showed that soil organisms, particularly arbuscular mycorrhizal fungi (AMF) and soil nematodes, elicited the greatest relative effects on ecosystem multifunctionality. Structural equation models revealed indirect effects of tree species richness on ecosystem multifunctionality mediated by trophic interactions in soil micro-food webs. Specifically, we found a significant negative effect of gram-positive bacteria on soil nematode abundance (a top-down effect), and a significant positive effect of AMF biomass on soil nematode abundance (a bottom-up effect). Overall, our study emphasizes the significance of a multitrophic perspective in elucidating biodiversity-multifunctionality relationships and highlights the conservation of functioning soil micro-food webs to maintain multiple ecosystem functions.


Assuntos
Ecossistema , Micorrizas , Cadeia Alimentar , Árvores , Solo/química , Biodiversidade , Plantas , Carbono
5.
Reprod Biol Endocrinol ; 22(1): 37, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576003

RESUMO

Inadequate endometrial receptivity often results in embryo implantation failure and miscarriage. Human chorionic gonadotropin (hCG) is a key signaling molecule secreted during early embryonic development, which regulates embryonic maternal interface signaling and promotes embryo implantation. This study aimed to examine the impact of hCG on endometrial receptivity and its underlying mechanisms. An exploratory study was designed, and endometrial samples were obtained from women diagnosed with simple tubal infertility or male factor infertile (n = 12) and recurrent implantation failure (RIF, n = 10). Using reverse transcription-quantitative PCR and western blotting, luteinizing hormone (LH)/hCG receptor (LHCGR) levels and autophagy were detected in the endometrial tissues. Subsequently, primary endometrial stromal cells (ESCs) were isolated from these control groups and treated with hCG to examine the presence of LHCGR and markers of endometrial receptivity (HOXA10, ITGB3, FOXO1, LIF, and L-selectin ligand) and autophagy-related factors (Beclin1, LC3, and P62). The findings revealed that the expressions of receptivity factors, LHCGR, and LC3 were reduced in the endometrial tissues of women with RIF compared with the control group, whereas the expression of P62 was elevated. The administration of hCG to ESCs specifically activated LHCGR, stimulating an increase in the endometrial production of HOXA10, ITGB3, FOXO1, LIF and L-selectin ligands. Furthermore, when ESCs were exposed to 0.1 IU/mL hCG for 72 h, the autophagy factors Beclin1 and LC3 increased within the cells and P62 decreased. Moreover, the apoptotic factor Bax increased and Bcl-2 declined. However, when small interfering RNA was used to knock down LHCGR, hCG was less capable of controlling endometrial receptivity and autophagy molecules in ESCs. In addition, hCG stimulation enhanced the phosphorylation of ERK1/2 and mTOR proteins. These results suggest that women with RIF exhibit lower levels of LHCGR and compromised autophagy function in their endometrial tissues. Thus, hCG/LHCGR could potentially improve endometrial receptivity by modulating autophagy and apoptosis.


Assuntos
Endométrio , Selectina L , Gravidez , Humanos , Masculino , Feminino , Proteína Beclina-1 , Selectina L/metabolismo , Endométrio/metabolismo , Gonadotropina Coriônica/farmacologia , Gonadotropina Coriônica/metabolismo , Implantação do Embrião/fisiologia , Autofagia , Células Estromais/metabolismo , Apoptose
6.
Protein Expr Purif ; 222: 106522, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851552

RESUMO

OBJECTIVE: To screen and obtain specific anti-lymphocyte activation gene-3 (LAG3) nanobody sequences, purify and express recombinant anti-LAG3 nanobody, and verify its effect on promoting T cells to kill tumor cells. METHODS: Based on the camel derived natural nanobody phage display library constructed by the research group, the biotinylated LAG3 antigen was used as the target, and the anti-LAG3 nanobody sequences were screened by biotin-streptavidin liquid phase screening, phage-ELISA and sequencing. The sequence-conjµgated human IgG1 Fc fragment was obtained, the recombinant anti-LAG3 nanobody expression vector was constructed, the expression of the recombinant anti-LAG3 nanobody was induced by IPTG and purified, and the characteristics and functions of the recombinant anti-LAG3 nanobody were verified by SDS-PAGE, Western blot, cytotoxicity assay, etc. RESULTS: One anti-LAG3 nanobody sequence was successfully screened, and the corresponding recombinant anti-LAG3 nanobody-expressing bacteria were constructed. The results of SDS-PAGE, Western blot and cytotoxicity assay showed that the recombinant anti-LAG3 nanobody was successfully expressed, which was specific, and it could promote the killing ability of T cells against tumor cells, and the optimal concentration was 200 µg/mL. CONCLUSION: The recombinant anti-LAG3 nanobody screened and expressed has specific and auxiliary anti-tumor cell effects, which lays a foundation for its subsequent application.

7.
Inorg Chem ; 63(15): 6743-6751, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38573011

RESUMO

The development of a solid-state electrolyte (SSE) is crucial for overcoming the side reactions of metal potassium anodes and advancing the progress of K-ion batteries (KIBs). Exploring the diffusion mechanism of the K ion in SSE is important for deepening our understanding and promoting its development. In this study, we conducted static calculations and utilized deep potential molecular dynamics (DeepMD) to investigate the behavior of cubic K3SbS4. The original K3SbS4 exhibited poor ionic conductivity, but we discovered that introducing heterovalent tungsten doping created vacancies, which significantly reduced the activation energy to 0.12 eV and enhanced the ionic conductivity to 1.80 × 10-2 S/cm. The diffusion of K-ions in K3SbS4 primarily occurs through the exchange of positions with K vacancies. This research provides insights into the design of SSE with high ionic conductivity. Furthermore, it highlights the effectiveness of DeepMD as a powerful tool for studying the SSE.

8.
Bioorg Med Chem ; 108: 117776, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38852257

RESUMO

Myocardial ischemia/reperfusion (MI/R) is a common cardiovascular disease that seriously affects the quality of life and prognosis of patients. In recent years, matrine has attracted widespread attention in the treatment of cardiovascular diseases. This study designed, synthesized, and characterized 20 new matrine derivatives and studied their protective effects on ischemia-reperfusion injury through in vivo and in vitro experiments. Based on cellular assays, most newly synthesized derivatives have a certain protective effect on Hypoxia/Reoxygenation (H/R) induced H9C2 cell damage, with compound 22 having the best activity and effectively reducing cell apoptosis and necrosis. In vitro experimental data shows that compound 22 can significantly reduce the infarct size of rat myocardium and improve cardiac function after MI/R injury. In summary, compound 22 is a new potential cardioprotective agent that can promote angiogenesis and enhance antioxidant activity by activating ADCY5, CREB3l4, and VEGFA, thereby protecting myocardial cell apoptosis and necrosis induced by MI/R.


Assuntos
Alcaloides , Apoptose , Desenho de Fármacos , Matrinas , Traumatismo por Reperfusão Miocárdica , Quinolizinas , Ratos Sprague-Dawley , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/síntese química , Animais , Quinolizinas/farmacologia , Quinolizinas/síntese química , Quinolizinas/química , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Apoptose/efeitos dos fármacos , Masculino , Relação Estrutura-Atividade , Estrutura Molecular , Cardiotônicos/farmacologia , Cardiotônicos/síntese química , Cardiotônicos/química , Relação Dose-Resposta a Droga , Linhagem Celular , Neovascularização Fisiológica/efeitos dos fármacos , Angiogênese
9.
Ear Hear ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38769615

RESUMO

OBJECTIVES: Children with cochlear implants (CIs) face challenges in perceiving fundamental frequency (F0) information because CIs do not transmit F0 effectively. In Mandarin, F0 can contrast meanings at the word level, that is, via lexical tones with distinct F0 contours, and signal contrastive relations between words at the utterance-level, that is, via contrastive focus with expanded F0 range and longer duration. Mandarin-speaking children with CIs have been reported to face challenges in producing distinct F0 contours across tones, but early implantation facilitates tonal acquisition. However, it is still unclear if utterance-level prosody, such as contrastive focus, is also challenging for these children, and if early implantation also offers benefits for focus production. Therefore, this study asked how accurately children with CIs can produce contrastive focus, and if early implantation leads to more accurate focus production, with acoustic patterns approaching that of children with typical hearing (TH). DESIGN: Participants included 55 Mandarin-speaking children (3 to 7 years) with CIs and 55 age-matched children with TH. Children produced noun phrases with and without contrastive focus, such as RED-COLORED cat versus red-colored cat. Three adult native listeners perceptually scored the productions as correct or incorrect. The "correct" productions were then acoustically analyzed in terms of F0 range and duration. RESULTS: Based on the perceptual scores, children with CIs produced focus with significantly lower accuracy (38%) than their TH peers (84%). The acoustic analysis on their "correct" productions showed that children with TH used both F0 and duration to mark focus, producing focal syllables with an expanded F0 range and long duration, and postfocal syllables with a reduced F0 range and short duration. However, children with CIs differed from children with TH in that they produced focal syllables with long duration but not an expanded F0 range, although they produced postfocal syllables with a reduced F0 range and short duration like their TH peers. In addition, early implantation correlated with the percept of more accurate focus productions and better use of F0 range in focal marking. CONCLUSIONS: This study finds that Mandarin-speaking children with CIs are still learning to apply appropriate acoustic cues to contrastive focus. The challenge appears to lie in the use of an expanded F0 range to mark focus, probably related to the limited transmission of F0 information through the CI devices. These findings thus have implications for parents and those working with children with CIs, showing that utterance-level prosody also requires speech remediation, and underscores the critical role of identifying problems early in the acquisition of F0 functions in Mandarin, not only at the word level but also at the utterance-level.

10.
Cell Mol Life Sci ; 80(7): 195, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37395809

RESUMO

Organ fibrosis caused by chronic allograft rejection is a major concern in the field of transplantation. Macrophage-to-myofibroblast transition plays a critical role in chronic allograft fibrosis. Adaptive immune cells (such as B and CD4+ T cells) and innate immune cells (such as neutrophils and innate lymphoid cells) participate in the occurrence of recipient-derived macrophages transformed to myofibroblasts by secreting cytokines, which eventually leads to fibrosis of the transplanted organ. This review provides an update on the latest progress in understanding the plasticity of recipient-derived macrophages in chronic allograft rejection. We discuss here the immune mechanisms of allograft fibrosis and review the reaction of immune cells in allograft. The interactions between immune cells and the process of myofibroblast formulation are being considered for the potential therapeutic targets of chronic allograft fibrosis. Therefore, research on this topic seems to provide novel clues for developing strategies for preventing and treating allograft fibrosis.


Assuntos
Imunidade Inata , Linfócitos , Humanos , Macrófagos , Aloenxertos , Fibrose
11.
Neurol Sci ; 45(4): 1419-1428, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38102519

RESUMO

In recent years, the stroke incidence has been increasing year by year, and the related sequelae after stroke, such as cognitive impairment, motor dysfunction, and post-stroke depression, seriously affect the patient's rehabilitation and daily activities. Repetitive transcranial magnetic stimulation (rTMS), as a safe, non-invasive, and effective new rehabilitation method, has been widely recognized in clinical practice. This article reviews the application and research progress of rTMS in treating different functional impairments (cognitive impairment, motor dysfunction, unilateral spatial neglect, depression) after stroke in recent years, and preliminary summarized the possible mechanisms. It has been found that the key parameters that determine the effectiveness of rTMS in improving post-stroke functional impairments include pulse number, stimulated brain areas, stimulation intensity and frequency, as well as duration. Generally, high-frequency stimulation is used to excite the ipsilateral cerebral cortex, while low-frequency stimulation is used to inhibit the contralateral cerebral cortex, thus achieving a balance of excitability between the two hemispheres. However, the specific mechanisms and the optimal stimulation mode for different functional impairments have not yet reached a consistent conclusion, and more research is needed to explore and clarify the best way to use rTMS. Furthermore, we will identify the issues and challenges in the current research, explore possible mechanisms to deepen understanding of rTMS, propose future research directions, and offer insightful insights for better clinical applications.


Assuntos
Agnosia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Estimulação Magnética Transcraniana , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Encéfalo , Córtex Cerebral
12.
BMC Musculoskelet Disord ; 25(1): 354, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704573

RESUMO

BACKGROUND: This study aimed to investigate the impact of nursing interventions on the rehabilitation outcomes of patients after lumbar spine surgery and to provide effective references for future postoperative care for patients undergoing lumbar spine surgery. METHODS: The study included two groups: a control group receiving routine care and an observation group receiving additional comprehensive nursing care. The comprehensive care encompassed postoperative rehabilitation, pain, psychological, dietary management, and discharge planning. The Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), Short-Form 36 (SF-36) Health Survey, self-rating depression scale (SDS) and self-rating anxiety scale(SAS) were used to assess physiological and psychological recovery. Blood albumin, haemoglobin, neutrophil counts, white blood cell counts, red blood cell counts, inflammatory markers (IL-6, IL-10, and IFN-γ) were measured, and the incidence of postoperative adverse reactions was also recorded. RESULTS: Patients in the observation group exhibited significantly improved VAS, ODI, SF-36, SDS and SAS scores assessments post-intervention compared to the control group (P < 0.05). Moreover, levels of IL-6, IL-10, and IFN-γ were more favorable in the observation group post-intervention (P < 0.05), indicating a reduction in inflammatory response. There was no significant difference in the incidence of postoperative adverse reactions between the groups (P > 0.05), suggesting that the comprehensive nursing interventions did not increase the risk of adverse effects. CONCLUSION: Comprehensive nursing interventions have a significant impact on the postoperative recovery outcomes of patients with LSS, alleviating pain, reducing inflammation levels, and improving the overall quality of patient recovery without increasing the patient burden. Therefore, in clinical practice, it is important to focus on comprehensive nursing interventions for patients with LSS to improve their recovery outcomes and quality of life.


Assuntos
Vértebras Lombares , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Vértebras Lombares/cirurgia , Resultado do Tratamento , Adulto , Idoso , Medição da Dor , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/reabilitação , Avaliação da Deficiência , Cuidados Pós-Operatórios/métodos
13.
Brain Inj ; : 1-10, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828532

RESUMO

BACKGROUND: Cognitive impairment is a severe complication of acute respiratory distress syndrome (ARDS). Emerging studies have revealed the effects of pyrrolidine dithiocarbamate (PDTC) on improving surgery-induced cognitive impairment. The major aim of the study was to investigate whether PDTC protected against ARDS-induced cognitive dysfunction and to identify the underlying mechanisms involved. METHODS: The rat model of ARDS was established by intratracheal instillation of lipopolysaccharide (LPS), followed by treatment with PDTC. The cognitive function of rats was analyzed by the Morris Water Maze, and pro-inflammatory cytokines were assessed by quantitative real-time PCR, enzyme-linked immunosorbent assay, and western blot assays. A dual-luciferase reporter gene assay was performed to identify the relationship between miR-181c and its target gene, TAK1 binding protein 2 (TAB2). RESULTS: The results showed that PDTC improved cognitive impairment and alleviated neuroinflammation in the hippocampus in LPS-induced ARDS model. Furthermore, we demonstrated that miR-181c expression was downregulated in the hippocampus of the ARDS rats, which was restored by PDTC treatment. In vitro studies showed that miR-181c alleviated LPS-induced pro-inflammatory response by inhibiting TAB2, a critical molecule in the nuclear factor (NF)-κB signaling pathway. CONCLUSION: PDTC improves cognitive impairment in LPS-induced ARDS by regulating miR-181c/NF-κB axis-mediated neuroinflammation, providing a potential opportunity for the treatment of this disease.

14.
J Biol Chem ; 298(6): 102006, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35504354

RESUMO

The discovery of reduced flavin mononucleotide and fatty aldehydes as essential factors of light emission facilitated study of bacterial luminescence. Although the molecular mechanisms underlying bacterial luminescence have been studied for more than 60 years, the structure of the bacterial fatty acid reductase complex remains unclear. Here, we report the cryo-EM structure of the Photobacterium phosphoreum fatty acid reductase complex LuxC-LuxE to a resolution of 2.79 Å. We show that the active site Lys238/Arg355 pair of LuxE is >30 Å from the active site Cys296 of LuxC, implying that catalysis relies on a large conformational change. Furthermore, mutagenesis and biochemical experiments support that the L-shaped cleft inside LuxC plays an important role in substrate binding and reaction. We obtained a series of mutants with significantly improved activity as measured by in vitro bioluminescence assays and demonstrated that the double mutant W111A/F483K displayed the highest activity (370% of the WT). Our results indicated that the activity of LuxC significantly affects the bacterial bioluminescence reaction. Finally, we expressed this mutated lux operon in Escherichia coli but observed that the in vivo concentrations of ATP and NADPH limited the enzyme activity; thus, we conclude that the luminous intensity mainly depends on the level of metabolic energy.


Assuntos
Aldeído Oxirredutases , Proteínas de Bactérias , Oxirredutases , Photobacterium , Aldeído Oxirredutases/química , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Microscopia Crioeletrônica , Escherichia coli/genética , Luminescência , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Óperon , Oxirredutases/química , Oxirredutases/genética , Oxirredutases/metabolismo , Photobacterium/genética
15.
J Exp Bot ; 74(10): 3019-3032, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-36879436

RESUMO

Leaf rust, caused by the fungal pathogen Puccinia triticina (Pt), is one of the major and dangerous diseases of wheat, and has caused serious yield loss of wheat worldwide. Here, we investigated adult-plant resistance (APR) to leaf rust in a recombinant inbred line (RIL) population derived from 'Xinmai 26' and 'Zhoumai 22' over 3 years. Linkage mapping for APR to leaf rust revealed four quantitative trait loci (QTL) in this RIL population. Two QTL, QLr.hnau-2BS and QLr.hnau-3BS were contributed by 'Zhoumai22', whereas QLr.hnau-2DS and QLr.hnau-5AL were contributed by 'Xinmai 26'. The QLr.hnau-2BS covering a race-specific resistance gene Lr13 showed the most stable APR to leaf rust. Overexpression of Lr13 significantly increased APR to leaf rust. Interestingly, we found that a CNL(coiled coil-nucleotide-binding site-leucine-rich repeat)-like gene, TaCN, in QLr.hnau-2BS completely co-segregated with leaf rust resistance. The resistant haplotype TaCN-R possessed half the sequence of the coiled-coil domain of TaCN protein. Lr13 strongly interacted with TaCN-R, but did not interact with the full-length TaCN (TaCN-S). In addition, TaCN-R was significantly induced after Pt inoculation and changed the sub-cellular localization of Lr13 after interaction. Therefore, we hypothesized that TaCN-R mediated leaf rust resistance possibly by interacting with Lr13. This study provides important QTL for APR to leaf rust, and new insights into understanding how a CNL gene modulates disease resistance in common wheat.


Assuntos
Basidiomycota , Locos de Características Quantitativas , Locos de Características Quantitativas/genética , Triticum/genética , Triticum/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Mapeamento Cromossômico , Resistência à Doença/genética
16.
Biotechnol Bioeng ; 120(3): 778-792, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36477904

RESUMO

Solid plates have been used for microbial monoclonal isolation, cultivation, and colony picking since 1881. However, the process is labor- and resource-intensive for high-throughput requirements. Currently, several instruments have been integrated for automated and high-throughput picking, but complicated and expensive. To address these issues, we report a novel integrated platform, the single-cell microliter-droplet screening system (MISS Cell), for automated, high-throughput microbial monoclonal colony cultivation and picking. We verified the monoclonality of droplet cultures in the MISS Cell and characterized culture performance. Compared with solid plates, the MISS Cell generated a larger number of monoclonal colonies with higher initial growth rates using fewer resources. Finally, we established a workflow for automated high-throughput screening of Corynebacterium glutamicum using the MISS Cell and identified high glutamate-producing strains. The MISS Cell can serve as a universal platform to efficiently produce monoclonal colonies in high-throughput applications, overcoming the limitations of solid plates to promote rapid development in biotechnology.


Assuntos
Biotecnologia , Corynebacterium glutamicum , Ensaios de Triagem em Larga Escala
17.
Nephrol Dial Transplant ; 39(1): 95-102, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37437905

RESUMO

BACKGROUND: The effectiveness of multitarget combination therapy with a corticosteroid, cyclosporine and mycophenolate mofetil for idiopathic membranous nephropathy (IMN) is unclear. In the present study, we aimed to compare the efficacy and safety of multitarget therapy with a cyclical corticosteroid-cyclophosphamide regimen in patients with IMN. METHODS: This was a single-centre, prospective, randomized, controlled trial. We randomly assigned patients with IMN to receive multitarget therapy (a combination of prednisone, cyclosporine and mycophenolate mofetil) or 6-month cyclical treatment with a corticosteroid and cyclophosphamide. The study patients were followed up for 12 months. The primary outcome was a composite of complete or partial remissions at 12 months. Adverse events were also assessed. RESULTS: The study cohort comprised 78 patients, 39 of whom received multitarget therapy and the other 39 cyclical alternating treatment with a corticosteroid and cyclophosphamide. At 12 months, 31 of 39 patients (79%) in the multitarget therapy group and 34 of 39 (87%) in the corticosteroid-cyclophosphamide group had achieved complete or partial remissions (relative risk 0.93; 95% confidence interval 0.72-1.21; P = .85; log-rank test). The prevalence of adverse events was significantly lower in the multitarget therapy group than in the corticosteroid-cyclophosphamide group [46% (18 of 39) vs 74% (29 of 39); P < .05]. CONCLUSIONS: Multitarget therapy for IMN patients is noninferior to cyclical alternating treatment with corticosteroid and cyclophosphamide in inducing proteinuria remission and has a better safety profile than the corticosteroid-cyclophosphamide combination.


Assuntos
Ciclosporina , Glomerulonefrite Membranosa , Humanos , Ciclosporina/uso terapêutico , Ácido Micofenólico/uso terapêutico , Imunossupressores/uso terapêutico , Glomerulonefrite Membranosa/tratamento farmacológico , Estudos Prospectivos , Ciclofosfamida/uso terapêutico , Corticosteroides/uso terapêutico , Quimioterapia Combinada
18.
Cancer Control ; 30: 10732748231185025, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37339928

RESUMO

BACKGROUND: At present, there is no objective prognostic index available for patients with esophageal squamous cell carcinoma (ESCC) who underwent intensity-modulated radiotherapy (IMRT). This study is to develop a nomogram based on hematologic inflammatory indices for ESCC patients treated with IMRT. METHODS: 581 patients with ESCC receiving definitive IMRT were enrolled in our retrospective study. Of which, 434 patients with treatment-naïve ESCC in Fujian Cancer Hospital were defined as the training cohort. Additional 147 newly diagnosed ESCC patients were used as the validation cohort. Independent predictors of overall survival (OS) were employed to establish a nomogram model. The predictive ability was evaluated by time-dependent receiver operating characteristic curves, the concordance index (C-index), net reclassification index (NRI), and integrated discrimination improvement (IDI). Decision curve analysis (DCA) was performed to assess the clinical benefits of the nomogram model. The entire series was divided into 3 risk subgroups stratified by the total nomogram scores. RESULTS: Clinical TNM staging, primary gross tumor volume, chemotherapy, neutrophil-to-lymphocyte ratio and platelet lymphocyte ratio were independent predictors of OS. Nomogram was developed incorporating these factors. Compared with the 8th American Joint Committee on Cancer (AJCC) staging, the C-index for 5-year OS (.627 and .629) and the AUC value of 5-year OS (.706 and .719) in the training and validation cohorts (respectively) were superior. Furthermore, the nomogram model presented higher NRI and IDI. DCA also demonstrated that the nomogram model provided greater clinical benefit. Finally, patients with <84.8, 84.8-151.4, and >151.4 points were categorized into low-risk, intermediate-risk, and high-risk groups. Their 5-year OS rates were 44.0%, 23.6%, and 8.9%, respectively. The C-index was .625, which was higher than the 8th AJCC staging. CONCLUSIONS: We have developed a nomogram model that enables risk-stratification of patients with ESCC receiving definitive IMRT. Our findings may serve as a reference for personalized treatment.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Radioterapia de Intensidade Modulada , Humanos , Nomogramas , Prognóstico , Carcinoma de Células Escamosas do Esôfago/radioterapia , Estudos Retrospectivos
19.
Microb Ecol ; 86(2): 1096-1106, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36258041

RESUMO

Global climate change is characterized by altered global atmospheric composition, including elevated CO2 and O3, with important consequences on soil fungal communities. However, the function and community composition of soil fungi in response to elevated CO2 together with elevated O3 in paddy soils remain largely unknown. Here we used twelve open-top chamber facilities (OTCs) to evaluate the interactive effect of CO2 (+ 200 ppm) and O3 (+ 40 ppb) on the diversity, gene abundance, community structure, and functional composition of soil fungi during the growing seasons of two rice cultivars (Japonica, Wuyujing 3 vs. Nangeng 5055) in a Chinese paddy soil. Elevated CO2 and O3 showed no individual or combined effect on the gene abundance or relative abundance of soil fungi, but increased structural complexity of soil fungal communities, indicating that elevated CO2 and/or O3 promoted the competition of species-species interactions. When averaged both cultivars, elevated CO2 showed no individual effect on the diversity or abundance of functional guilds of soil fungi. By contrast, elevated O3 significantly reduced the relative abundance and diversity of symbiotrophic fungi by an average of 47.2% and 39.1%, respectively. Notably, elevated O3 exerts stronger effects on the functional processes of fungal communities than elevated CO2. The structural equation model revealed that elevated CO2 and/or O3 indirectly affected the functional composition of soil fungi through community structure and diversity of soil fungi. Root C/N and soil environmental parameters were identified as the top direct predictors for the community structure of soil fungi. Furthermore, significant correlations were identified between saprotrophic fungi and root biomass, symbiotrophic fungi and root carbon, the pathotroph-symbiotroph and soil pH, as well as pathotroph-saprotroph-symbiotroph and soil microbial biomass carbon. These results suggest that climatic factors substantially affected the functional processes of soil fungal, and threatened soil function and food production, highlighting the detrimental impacts of high O3 on the function composition of soil biota.


Assuntos
Ozônio , Solo , Dióxido de Carbono , Biomassa , Fungos/genética , Carbono , Microbiologia do Solo , Ozônio/farmacologia
20.
Inorg Chem ; 62(8): 3395-3408, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36763897

RESUMO

Half-sandwich iridium(III) complexes show potential value in the anticancer field. However, complexes with favorable luminescence performance are rare, which limits further investigation of the anticancer mechanism. In this paper, 10 triphenylamine-modified fluorescent half-sandwich iridium(III) pyridine complexes {[(η5-Cpx)Ir(L)Cl2]} (Ir1-Ir10) were prepared and showed potential antiproliferative activity, effectively inhibiting the migration of A549 cells. Ir6, showing the best activity among these complexes, exhibited excellent fluorescence performance (absolute fluorescence quantum yield of 15.17%) in solution. Laser confocal detection showed that Ir6 followed an energy-dependent cellular uptake mechanism, specifically accumulating in mitochondria (Pearson co-localization coefficient of 0.95). A Western blot assay further confirmed the existence of a mitochondrial apoptotic channel. Additionally, Ir6 could arrest the cell cycle at the G2/M phase, catalyze NADH oxidation, reduce the mitochondrial membrane potential, induce an increase in the level of intracellular reactive oxygen species, and exhibit a mechanism of oxidation. An in vivo antitumor assay confirmed that Ir6 can effectively inhibit tumor growth and is safer than cisplatin.


Assuntos
Antineoplásicos , Complexos de Coordenação , Complexos de Coordenação/farmacologia , Antineoplásicos/farmacologia , Irídio/farmacologia , Cisplatino/farmacologia , Piridinas/farmacologia , Apoptose , Proliferação de Células , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA