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1.
Sci Rep ; 14(1): 16233, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004658

RESUMO

Saline-sodic stress restricts the absorption of zinc by rice, consequently impacting the photosynthesis process of rice plants. In this experiment, Landrace 9 was selected as the test material and the potting method was employed to investigate the influence of ZnO nanoparticles (ZnO NPs) on zinc absorption and chlorophyll fluorescence in rice grown in saline-sodic land. The research findings demonstrate that the application of ZnO NPs proves to be more advantageous for the growth of rice in saline-sodic soil. Notably, the application of ZnO NPs significantly decreases the levels of Na+ and MDA in rice leaves in saline-sodic soil, while increasing the levels of K+ and Zn2+. Additionally, ZnO NPs enhances the content of chloroplast pigments, specific energy flux, quantum yield, and the performance of active PSII reaction center (PIABS) in rice leaves under saline-sodic stress. Furthermore, the relative variable fluorescence (WK and VJ) and quantum energy dissipation rate (φDo) of rice are also reduced. Therefore, the addition of ZnO NPs enhances the transfer of electrons and energy within the rice photosystem when subjected to saline-sodic stress. This promotes photosynthesis in rice plants growing in saline-sodic land, increasing their resistance to saline-sodic stress and ultimately facilitating their growth and development.


Assuntos
Oryza , Fotossíntese , Folhas de Planta , Solo , Óxido de Zinco , Oryza/metabolismo , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Óxido de Zinco/farmacologia , Fotossíntese/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Solo/química , Clorofila/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Nanopartículas Metálicas/química , Fluorescência , Salinidade
3.
ChemMedChem ; : e202400349, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965060

RESUMO

Bacterial infection, which can trigger varieties of diseases and tens of thousands of deaths each year, poses  serious threats to human health. Particularly, the new dilemma caused by biofilms is gradually becoming a severe and tough problem in the biomedical field. Thus, the strategies to address these problems are considered an urgent task at present. Micro/nanomotors (MNMs), also named micro/nanoscale robots, are mostly driven by chemical energy or external field, exhibiting strong diffusion and self-propulsion in the liquid media, which has the potential for antibacterial applications. In particular, when MNMs are assembled in swarms, they become robust and efficient for biofilm removal. However, there is a lack of comprehensive review discussing the progress in this aspect. Bearing it in mind and based on our own research experience in this regard, the studies on MNMs driven by different mechanisms orchestrated for antibacterial activity and biofilm removal are timely and concisely summarized and discussed in this work, aiming to show the advantages of MNMs brought to this field. In addition, an outlook was proposed, hoping to provide the fundamental guidance for future development in this area.

4.
Clin Lab ; 70(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38965963

RESUMO

BACKGROUND: Immunohematology skill education is an important part of the transfusion medicine professional training. We tried to solve the difficulty of obtaining suitable and sufficient positive samples in the immunohematology education. METHODS: Different identification panels and panel cells were created by RhD-positive red blood cells (RBCs) and RhD-negative RBCs, according to the underlying antibodies. Diluted anti-D reagent was used as simulated plasma for identification. RESULTS: The antibody identification of single antibody with dose-effect and two antibodies present at the same time were successfully simulated. CONCLUSIONS: It is a practical and cheap method for antibody identification training to use RhD blood group, especially when positive samples are short.


Assuntos
Tipagem e Reações Cruzadas Sanguíneas , Sistema do Grupo Sanguíneo Rh-Hr , Humanos , Sistema do Grupo Sanguíneo Rh-Hr/imunologia , Sistema do Grupo Sanguíneo Rh-Hr/sangue , Tipagem e Reações Cruzadas Sanguíneas/métodos , Eritrócitos/imunologia , Isoanticorpos/sangue , Isoanticorpos/imunologia , Hematologia/métodos , Imunoglobulina rho(D)/imunologia , Imunoglobulina rho(D)/sangue , Medicina Transfusional/métodos
5.
Mol Med Rep ; 30(3)2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38963030

RESUMO

DNA methylation is one of the earliest and most significant epigenetic mechanisms discovered. DNA methylation refers, in general, to the addition of a methyl group to a specific base in the DNA sequence under the catalysis of DNA methyltransferase, with S­adenosine methionine as the methyl donor, via covalent bonding and chemical modifications. DNA methylation is an important factor in inducing cancer. There are different types of DNA methylation, and methylation at different sites plays different roles. It is well known that the progression of colorectal cancer (CRC) is affected by the methylation of key genes. The present review did not only discuss the potential relationship between DNA methylation and CRC but also discussed how DNA methylation affects the development of CRC by affecting key genes. Furthermore, the clinical significance of DNA methylation in CRC was highlighted, including that of the therapeutic targets and biomarkers of methylation; and the importance of DNA methylation inhibitors was discussed as a novel strategy for treatment of CRC. The present review did not only focus upon the latest research findings, but earlier reviews were also cited as references to older literature.


Assuntos
Neoplasias Colorretais , Metilação de DNA , Epigênese Genética , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Animais
6.
Int Immunopharmacol ; 138: 112617, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38972213

RESUMO

Severe steatosis in donor livers is contraindicated for transplantation due to the high risk of ischemia-reperfusion injury (IRI). Although Ho-1 gene-modified bone marrow mesenchymal stem cells (HO-1/BMMSCs) can mitigate IRI, the role of gut microbiota and metabolites in this protection remains unclear. This study aimed to explore how gut microbiota and metabolites contribute to HO-1/BMMSCs-mediated protection against IRI in severe steatotic livers. Using rat models and cellular models (IAR20 and THLE-2 cells) of steatotic liver IRI, this study revealed that ischemia-reperfusion led to significant liver and intestinal damage, heightened immune responses, impaired liver function, and altered gut microbiota and metabolite profiles in rats with severe steatosis, which were partially reversed by HO-1/BMMSCs transplantation. Integrated microbiome and metabolome analyses identified gut microbial metabolite oleanolic acid as a potential protective agent against IRI. Experimental validation showed that oleanolic acid administration alone alleviated IRI and inhibited ferroptosis in both rat and cellular models. Network pharmacology and molecular docking implicated KEAP1/NRF2 pathway as a potential target of oleanolic acid. Indeed, OA experimentally upregulated NRF2 activity, which underlies its inhibition of ferroptosis and protection against IRI. The gut microbial metabolite OA protects against IRI in severe steatotic liver by promoting NRF2 expression and activity, thereby inhibiting ferroptosis.

7.
Exp Gerontol ; 194: 112514, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971132

RESUMO

Mitochondrial dysfunction is a prominent hallmark of Alzheimer's disease (AD). The transcriptional coactivator PPARγ coactivator 1 (PGC-1a) has been identified as a key regulator of mitochondrial biogenesis and function. However, the precise structure/function relationship between PGC-1a and mitochondrial quality control remains incompletely understood. In this study, we investigated the impact of PGC-1a on AD pathology and its underlying mechanisms with a specific focus on mitochondrial axonal transport. Additionally, we generated two PGC-1α mutants by substituting leucine residues at positions 148 and 149 within the LKKLL motif or at positions 209 and 210 within the LLKYL motif with alanine. Subsequently, we examined the effects of these mutants on mutAPP-induced abnormalities in anterograde and retrograde axonal transport, disrupted mitochondrial distribution, and impaired mitophagy. Mutagenesis studies revealed that the LLKYL motif at amino acid position 209-210 within PGC-1α plays an essential role in its interaction with estrogen-related receptors (ERRα), which is necessary for restoring normal mitochondrial anterograde axonal transport, maintaining proper mitochondrial distribution, and ultimately preventing neuronal apoptosis. Furthermore, it was found that the Leu-rich motif at amino acids 209-210 within PGC-1α is crucial for rescuing mutAPP-induced impairment in mitophagy and loss of membrane potential by restoring normal mitochondrial retrograde axonal transport. Conversely, mutation of residues 148 and 149 in the LKKLL motif does not compromise the effectiveness of PGC-1α. These findings provide valuable insights into the molecular determinants governing specificity of action for PGC-1α involved in regulating mutAPP-induced deficits in mitochondrial axonal trafficking. Moreover, they suggest a potential therapeutic target for addressing Alzheimer's disease.

8.
J Nat Prod ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976838

RESUMO

Heterologous expression of an atr terpenoid gene cluster derived from Streptomyces atratus Gö66 in S. albus J1074 led to the discovery of three novel labdane diterpenoids featuring an unprecedented 6/6/5-fused tricyclic skeleton, designated as atralabdans A-C (1-3), along with a known compound, labdanmycin A. Compounds 1-3 were identified through extensive spectroscopic analysis, including NMR calculations with DP4+ probability analysis, and a comparative assessment of experimental and theoretical electronic circular dichroism (ECD) spectra. A plausible biosynthetic pathway for these compounds was proposed. Compounds 1-3 exhibited inhibitory activity against the human neurotropic coxsackievirus B3 (CVB3); 1 was the most potent, surpassing the positive control ribavirin with a higher therapeutic index.

9.
Lab Invest ; 104(8): 102090, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38830579

RESUMO

Gastric cancer (GC) is one of the most common clinical malignant tumors worldwide, with high morbidity and mortality. Presently, the overall response rate to immunotherapy is low, and current methods for predicting the prognosis of GC are not optimal. Therefore, novel biomarkers with accuracy, efficiency, stability, performance ratio, and wide clinical application are needed. Based on public data sets, the chemotherapy cohort and immunotherapy cohort from Sun Yat-sen University Cancer Center, a series of bioinformatics analyses, such as differential expression analysis, survival analysis, drug sensitivity prediction, enrichment analysis, tumor immune dysfunction and exclusion analysis, single-sample gene set enrichment analysis, stemness index calculation, and immune cell infiltration analysis, were performed for screening and preliminary exploration. Immunohistochemical staining and in vitro experiments were performed for further verification. Overexpression of COX7A1 promoted the resistance of GC cells to Oxaliplatin. COX7A1 may induce immune escape by regulating the number of fibroblasts and their cellular communication with immune cells. In summary, measuring the expression levels of COX7A1 in the clinic may be useful in predicting the prognosis of GC patients, the degree of chemotherapy resistance, and the efficacy of immunotherapy.

10.
J Phys Chem A ; 128(27): 5243-5252, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38937149

RESUMO

Direct methanol fuel cells (DMFCs) have attracted increasing attention as a very promising and important energy source. In this paper, density functional theory (DFT) is used to study the structure and O-H fracture mechanism of methanol adsorption on PtnCu4-n (111) (n = 1, 2, 3) binary metal catalyst surfaces under different coverages. By comparing the adsorption energy and dehydrogenation energy barriers of methanol, it is found that the adsorption strength and dehydrogenation energy barriers of methanol on Pt and Cu sites decreased with increasing coverage. At the same Pt and Cu ratio, methanol is more easily adsorbed on Cu sites. When Pt/Cu = 3:1 and 1:3, the PtCu binary catalyst has a significant impact on the energy barrier of breaking the O-H bond in methanol with the increase of coverage. Especially when Pt/Cu = 1:3 and the coverage is 1/4 ML, the energy barriers of O-H bond breaking in methanol on Pt and Cu sites are 0.63 and 0.61 eV, respectively, which are lower than that on pure Pt. It means that the Cu sites played a very important role in reducing the O-H fracture energy barrier of methanol. When Pt/Cu = 1:1, the change in the dehydrogenation energy barrier of methanol on Pt sites and Cu sites is not significant, indicating that the coverage has little effect on it.

11.
Front Psychol ; 15: 1351425, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38855302

RESUMO

Trustworthiness is the most significant predictor of trust and has a significant impact on people's levels of trust. Most trustworthiness-related research is empirical, and while it has a long history, it is challenging for academics to get insights that are applicable to their fields of study and to successfully transfer fragmented results into practice. In order to grasp their dynamic development processes through the mapping of network knowledge graphs, this paper is based on the Web of Science database and uses CiteSpace (6.2.R4) software to compile and visualize the 1,463 publications on trustworthy studies over the past 10 years. This paper aims to provide valuable references to theoretical research and the practice of Trustworthiness. The findings demonstrate that: over the past 10 years, trustworthiness-related research has generally increased in volume; trustworthiness research is concentrated in industrialized Europe and America, with American research findings having a bigger global impact; The University of California System, Harvard University, and Yale University are among the high-production institutions; the leading figures are represented by Alexander Todorov, Marco Brambilla, Bastian Jaeger, and others; the core authors are distinguished university scholars; however, the level of cooperation of the core author needs to be improved. The primary journal for publishing research on trustworthiness is the Journal of Personality and Social Psychology and Biology Letters. In addition, the study focuses on three distinct domains, involving social perception, facial clues, and artificial intelligence.

12.
Ageing Res Rev ; 99: 102364, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838786

RESUMO

BACKGROUND: There is controversy surrounding the association between preexisting frailty and increased mortality in candidates and recipients of solid-organ transplants. This meta-analysis aimed to evaluate the impact of preexisting frailty on survival outcomes in solid-organ transplant candidates and recipients. METHODS: A systematic search was conducted in the PubMed, Web of Sciences, and Embase databases until October 2, 2023. Two reviewers independently selected the eligible studies according to the PECOS criteria: Participants (candidates and recipients of solid-organ transplants), Exposure (frailty), Comparison (no-frailty), Outcomes (waitlist or posttransplant mortality), and Study design (retrospective or prospective cohort studies). The pooled effects were summarized by pooling the adjusted hazard ratio (HR) with 95 % confidence intervals (CI) for the frail patients than those without frailty. RESULTS: Sixteen studies with 10091 patients met the eligibility criteria. Depending on the frailty tools used, the prevalence of frailty in solid-organ transplant candidates/recipients ranged from 4.6 % to 45.1 %. Frailty was significantly associated with an increased risk of waitlist mortality (HR 2.44; 95 % CI 1.84-3.24) and posttransplant mortality (HR 2.23; 95 % CI 1.61-3.09) in solid-organ transplant candidates and recipients, respectively. Subgroup analyses showed that the association of preexisting frailty with waitlist mortality and posttransplant mortality appeared to stronger in kidney transplant candidates (HR 2.70; 95 % CI 1.93-3.78) and lung transplantation recipients (HR 2.52; 95 % CI 1.23-5.15). CONCLUSION: Frailty is a significant predictor of reduced survival in solid-organ transplant candidates and recipients. Assessment of frailty has the potential to identify patients who are suitable for transplantation.

13.
Heliyon ; 10(10): e30841, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38826728

RESUMO

Background: Long noncoding RNAs (lncRNAs) have emerged as critical regulators of colorectal cancer (CRC) progression, but their roles and underlying mechanisms in colorectal cancer liver metastases (CRLMs) remain poorly understood. Methods: To explore the expression patterns and functions of lncRNAs in CRLMs, we analyzed the expression profiles of lncRNAs in CRC tissues using the TCGA database and examined the expression patterns of lncRNAs in matched normal, CRC, and CRLM tissues using clinical samples. We further investigated the biological roles of LINC02257 in CRLM using in vitro and in vivo assays, and verified its therapeutic potential in a mouse model of CRLM. Results: Our findings showed that LINC02257 was highly expressed in metastatic CRC tissues and its expression was negatively associated with overall survival. Functionally, LINC02257 promoted CRC cell growth, migration, metastasis, and inhibited cell apoptosis in vitro, and enhanced liver metastasis in vivo. Mechanistically, LINC02257 up-regulated phosphorylated c-Jun N-terminal kinase (JNK) to promote CRLM. Conclusions: Our study revealed that LINC02257 played a key role in the proliferation and metastasis of CRC cells through the LINC02257/JNK axis. Targeting this axis may represent a promising therapeutic strategy for the treatment of liver metastases in patients with CRC.

14.
JCI Insight ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842948

RESUMO

Sleep disturbance usually accompanies anxiety disorders and exacerbates their incidence rates. The precise circuit mechanisms remain poorly understood. Here, we found that glutamatergic neurons in the posteroventral medial amygdala (MePVGlu) are involved in arousal and anxiety-like behaviors. Excitation of MePVGlu neurons not only promoted wakefulness but also increased anxiety-like behaviors. Different projections of MePVGlu neurons played various roles in regulating anxiety-like behaviors and sleep-wakefulness. MePVGlu neurons promoted wakefulness through the MePVGlu-posteromedial cortical amygdaloid area (PMCo) pathway and the MePVGlu-bed nucleus of the stria terminals (BNST) pathway. In contrast, MePVGlu neurons increased anxiety-like behaviors through the MePVGlu-ventromedial hypothalamus (VMH) pathway. Chronic sleep disturbance increased anxiety levels and reduced reparative sleep, accompanied by the enhanced excitability of MePVGlu-PMCo and MePVGlu-VMH circuits but suppressed responses of glutamatergic neurons in the BNST. Inhibition of the MePVGlu neurons could rescue chronic sleep deprivation-induced phenotypes. Our findings provide important circuit mechanisms for chronic sleep disturbance-induced hyperarousal response and obsessive anxiety-like behavior, and are expected to provide a promising strategy for treating sleep-related psychiatric disorders and insomnia.

15.
Compr Rev Food Sci Food Saf ; 23(4): e13371, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38853463

RESUMO

Nowadays, the food industry is facing challenges due to the simultaneous rise in global warming, population, and food consumption. As the integration of synthetic biology and food science, novel synthetic foods have obtained high attention to address these issues. However, these novel foods may cause potential risks related to human health. Four types of novel synthetic foods, including plant-based foods, cultured meat, fermented foods, and microalgae-based foods, were reviewed in the study. The original food sources, consumer acceptance, advantages and disadvantages of these foods were discussed. Furthermore, potential risk factors, such as nutritional, biological, and chemical risk factors, associated with these foods were described and analyzed. Additionally, the current detection methods (e.g., enzyme-linked immunosorbent assay, biosensors, chromatography, polymerase chain reaction, isothermal amplification, and microfluidic technology) and processing technologies (e.g., microwave treatment, ohmic heating, steam explosion, high hydrostatic pressure, ultrasound, cold plasma, and supercritical carbon dioxide) were reviewed and discussed critically. Nonetheless, it is crucial to continue innovating and developing new detection and processing technologies to effectively evaluate these novel synthetic foods and ensure their safety. Finally, approaches to enhance the quality of these foods were briefly presented. It will provide insights into the development and management of novel synthetic foods for food industry.


Assuntos
Manipulação de Alimentos , Alimentos Fermentados/análise , Manipulação de Alimentos/métodos , Inocuidade dos Alimentos/métodos , Microalgas/química , Fatores de Risco , Carne in vitro/análise
16.
Plant J ; 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38922743

RESUMO

Anthocyanins are natural pigments and dietary antioxidants that play multiple biological roles in plants and are important in animal and human nutrition. Low temperature (LT) promotes anthocyanin biosynthesis in many species including blood orange. A retrotransposon in the promoter of Ruby1, which encodes an R2R3 MYB transcription factor, controls cold-induced anthocyanin accumulation in blood orange flesh. However, the specific mechanism remains unclear. In this study, we characterized two LT-induced ETHYLENE RESPONSE FACTORS (CsERF054 and CsERF061). Both CsERF054 and CsERF061 can activate the expression of CsRuby1 by directly binding to a DRE/CRT cis-element within the retrotransposon in the promoter of CsRuby1, thereby positively regulating anthocyanin biosynthesis. Further investigation indicated that CsERF061 also forms a protein complex with CsRuby1 to co-activate the expression of anthocyanin biosynthetic genes, providing a dual mechanism for the upregulation of the anthocyanin pathway. These results provide insights into how LT mediates anthocyanin biosynthesis and increase the understanding of the regulatory network of anthocyanin biosynthesis in blood orange.

17.
J Clin Nurs ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923757

RESUMO

AIMS: To construct a conceptual framework on the process of family resilience during the first year following childhood leukaemia diagnosis. DESIGN: A longitudinal qualitative interview study. METHODS: A longitudinal qualitative study following a grounded theory methodology was employed. Semi-structured interviews were conducted with parents of children with leukaemia in a general hospital. The participants were recruited through purposive and theoretical sampling and longitudinal engagement was achieved by conducting interviews at 1, 3, 6, and 12 months after the leukaemia diagnosis. The core category and categories were saturated following the enrolment of parents of children with leukaemia. Data collection and analyses were performed simultaneously. RESULTS: Sixteen parents of children with leukaemia participated. The core category of 'families living with childhood leukaemia' refers to the process of family resilience during the first year following childhood leukaemia diagnosis, which includes three phases: (1) destruction and resiliency period; (2) adjustment and consolidation period; and (3) growth and planning period. CONCLUSION: This study explored the dynamic, complex and continuous processes of resilience among families coping with childhood leukaemia during the first year following diagnosis. Further research should design tailored family interventions that characterise the different phases of family resilience, aiming to support family well-being, integrity and functioning. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Both families and healthcare professionals must create an enabling environment that supports families coping with difficulties. Understanding the different phases of family resilience allows healthcare professionals to provide holistic care that meets the demands of families with childhood leukaemia. IMPACT: Unique knowledge emerged about the family's resiliency process when facing childhood leukaemia, suggesting a family-led revolution in understanding and managing childhood leukaemia. Therefore, the development of phased, resilience-based family interventions is imperative. REPORTING METHOD: This study was reported using the COREQ checklist. PATIENT OR PUBLIC CONTRIBUTION: Patients contributed via study participation.

18.
J Org Chem ; 89(13): 9381-9388, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38885147

RESUMO

A Pd(II)/N,N'-disulfonyl bisimidazoline-catalyzed asymmetric 1,4-conjugate addition reaction of low-cost arylboronic acids with readily available ß-substituted cyclic enones is described, providing a straightforward way of constructing cyclic all-carbon quaternary stereocenters with high enantioselectivity, in which ≥96% ee was obtained in most cases. The reaction proceeded without the protection of inert gas, making the operation process simple. Theoretical calculations have been applied to understand the origins of enantioselectivity.

19.
Vet Res ; 55(1): 80, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886823

RESUMO

Bacteria utilize intercellular communication to orchestrate essential cellular processes, adapt to environmental changes, develop antibiotic tolerance, and enhance virulence. This communication, known as quorum sensing (QS), is mediated by the exchange of small signalling molecules called autoinducers. AI-2 QS, regulated by the metabolic enzyme LuxS (S-ribosylhomocysteine lyase), acts as a universal intercellular communication mechanism across gram-positive and gram-negative bacteria and is crucial for diverse bacterial processes. In this study, we demonstrated that in Streptococcus suis (S. suis), a notable zoonotic pathogen, AI-2 QS enhances galactose utilization, upregulates the Leloir pathway for capsular polysaccharide (CPS) precursor production, and boosts CPS synthesis, leading to increased resistance to macrophage phagocytosis. Additionally, our molecular docking and dynamics simulations suggest that, similar to S. pneumoniae, FruA, a fructose-specific phosphoenolpyruvate phosphotransferase system prevalent in gram-positive pathogens, may also function as an AI-2 membrane surface receptor in S. suis. In conclusion, our study demonstrated the significance of AI-2 in the synthesis of galactose metabolism-dependent CPS in S. suis. Additionally, we conducted a preliminary analysis of the potential role of FruA as a membrane surface receptor for S. suis AI-2.


Assuntos
Galactose , Percepção de Quorum , Streptococcus suis , Streptococcus suis/fisiologia , Galactose/metabolismo , Percepção de Quorum/fisiologia , Virulência , Animais , Cápsulas Bacterianas/metabolismo , Lactonas/metabolismo , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/imunologia , Homosserina/análogos & derivados , Homosserina/metabolismo , Polissacarídeos Bacterianos/metabolismo
20.
J Neurosci ; 44(28)2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858079

RESUMO

Tau pathologies are detected in the brains of some of the most common neurodegenerative diseases including Alzheimer's disease (AD), Lewy body dementia (LBD), chronic traumatic encephalopathy (CTE), and frontotemporal dementia (FTD). Tau proteins are expressed in six isoforms with either three or four microtubule-binding repeats (3R tau or 4R tau) due to alternative RNA splicing. AD, LBD, and CTE brains contain pathological deposits of both 3R and 4R tau. FTD patients can exhibit either 4R tau pathologies in most cases or 3R tau pathologies less commonly in Pick's disease, which is a subfamily of FTD. Here, we report the isoform-specific roles of tau in FTD. The P301L mutation, linked to familial 4R tau FTD, induces mislocalization of 4R tau to dendritic spines in primary hippocampal cultures that were prepared from neonatal rat pups of both sexes. Contrastingly, the G272V mutation, linked to familial Pick's disease, induces phosphorylation-dependent mislocalization of 3R tau but not 4R tau proteins to dendritic spines. The overexpression of G272V 3R tau but not 4R tau proteins leads to the reduction of dendritic spine density and suppression of mEPSCs in 5-week-old primary rat hippocampal cultures. The decrease in mEPSC amplitude caused by G272V 3R tau is dynamin-dependent whereas that caused by P301L 4R tau is dynamin-independent, indicating that the two tau isoforms activate different signaling pathways responsible for excitatory synaptic dysfunction. Our 3R and 4R tau studies here will shed new light on diverse mechanisms underlying FTD, AD, LBD, and CTE.


Assuntos
Espinhas Dendríticas , Demência Frontotemporal , Mutação , Isoformas de Proteínas , Proteínas tau , Proteínas tau/metabolismo , Proteínas tau/genética , Animais , Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/patologia , Ratos , Masculino , Humanos , Feminino , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sinapses/metabolismo , Sinapses/patologia , Ratos Sprague-Dawley , Hipocampo/metabolismo , Hipocampo/patologia , Células Cultivadas
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