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1.
Nature ; 597(7875): 245-249, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34433964

RESUMO

Transient neuromodulation can have long-lasting effects on neural circuits and motivational states1-4. Here we examine the dopaminergic mechanisms that underlie mating drive and its persistence in male mice. Brief investigation of females primes a male's interest to mate for tens of minutes, whereas a single successful mating triggers satiety that gradually recovers over days5. We found that both processes are controlled by specialized anteroventral and preoptic periventricular (AVPV/PVpo) dopamine neurons in the hypothalamus. During the investigation of females, dopamine is transiently released in the medial preoptic area (MPOA)-an area that is critical for mating behaviours. Optogenetic stimulation of AVPV/PVpo dopamine axons in the MPOA recapitulates the priming effect of exposure to a female. Using optical and molecular methods for tracking and manipulating intracellular signalling, we show that this priming effect emerges from the accumulation of mating-related dopamine signals in the MPOA through the accrual of cyclic adenosine monophosphate levels and protein kinase A activity. Dopamine transients in the MPOA are abolished after a successful mating, which is likely to ensure abstinence. Consistent with this idea, the inhibition of AVPV/PVpo dopamine neurons selectively demotivates mating, whereas stimulating these neurons restores the motivation to mate after sexual satiety. We therefore conclude that the accumulation or suppression of signals from specialized dopamine neurons regulates mating behaviours across minutes and days.


Assuntos
AMP Cíclico/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Hipotálamo/citologia , Hipotálamo/metabolismo , Comportamento Sexual Animal , Transdução de Sinais , Animais , Copulação , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Impulso (Psicologia) , Feminino , Masculino , Camundongos , Optogenética , Área Pré-Óptica/citologia , Área Pré-Óptica/metabolismo , Resposta de Saciedade , Fatores de Tempo
2.
J Am Soc Nephrol ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857203

RESUMO

BACKGROUND: Chemical modifications on RNA profoundly impact RNA function and regulation. m6A, the most abundant RNA modification in eukaryotes, plays a pivotal role in diverse cellular processes and disease mechanisms. However, its importance is understudied in human chronic kidney disease (CKD) samples regarding its influence on pathological mechanisms. METHODS: LC-MS/MS and Methylated RNA Immunoprecipitation (MeRIP) sequencing were utilized to examine alterations in m6A levels and patterns in CKD samples. Overexpression of the m6A writer METTL3 in cultured kidney tubular cells was performed to confirm the impact of m6A in tubular cells and explore the biological functions of m6A modification on target genes. Additionally, tubule-specific deletion of Mettl3 (Ksp-Cre Mettl3f/f) mice and the use of anti-sense oligonucleotides inhibiting Mettl3 expression were utilized to reduce m6A modification in an animal kidney disease model. RESULTS: By examining 127 human CKD samples, we observed a significant increase in m6A modification and METTL3 expression in diseased kidneys. Epitranscriptomic analysis unveiled an enrichment of m6A modifications in transcripts associated with the activation of inflammatory signaling pathways, particularly the cGAS-STING pathway. m6A hypermethylation increased mRNA stability in cGAS and STING1, as well as elevated the expression of key proteins within the cGAS-STING pathway. Both the tubule-specific deletion of Mettl3 and the use of anti-sense oligonucleotides to inhibit Mettl3 expression protected mice from inflammation, reduced cytokine expression, decreased immune cell recruitment, and attenuated kidney fibrosis. CONCLUSIONS: Our research revealed heightened METTL3-mediated m6A modification in fibrotic kidneys, particularly enriching the cGAS-STING pathway. This hypermethylation increased mRNA stability for cGAS and STING1, leading to sterile inflammation and fibrosis.

3.
J Cell Physiol ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940190

RESUMO

Chondrosarcoma is a malignant bone tumor that emerges from abnormalities in cartilaginous tissue and is related with lung metastases. Nicotinamide phosphoribosyltransferase (NAMPT) is an adipocytokine reported to enhance tumor metastasis. Our results from clinical samples and the Gene Expression Omnibus data set reveal that NAMPT levels are markedly higher in chondrosarcoma patients than in normal individuals. NAMPT stimulation significantly increased lysyl oxidase (LOX) production in chondrosarcoma cells. Additionally, NAMPT increased LOX-dependent cell migration and invasion in chondrosarcoma by suppressing miR-26b-5p generation through the c-Src and Akt signaling pathways. Overexpression of NAMPT promoted chondrosarcoma metastasis to the lung in vivo. Furthermore, knockdown of LOX counteracted NAMPT-facilitated metastasis. Thus, the NAMPT/LOX axis presents a novel target for treating the metastasis of chondrosarcoma.

4.
Small ; 20(6): e2304743, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37803930

RESUMO

Converting solar energy into hydrogen energy using conjugated polymers (CP) is a promising solution to the energy crisis. Improving water solubility plays one of the critical factors in enhancing the hydrogen evolution rate (HER) of CP photocatalysts. In this study, a novel concept of incorporating hydrophilic side chains to connect the backbones of CPs to improve their HER is proposed. This concept is realized through the polymerization of carbazole units bridged with octane, ethylene glycol, and penta-(ethylene glycol) to form three new side-chain-braided (SCB) CPs: PCz2S-OCt, PCz2S-EG, and PCz2S-PEG. Verified through transient absorption spectra, the enhanced capability of PCz2S-PEG for ultrafast electron transfer and reduced recombination effects has been demonstrated. Small- and wide-angle X-ray scattering (SAXS/WAXS) analyses reveal that these three SCB-CPs form cross-linking networks with different mass fractal dimensions (f) in aqueous solution. With the lowest f value of 2.64 and improved water/polymer interfaces, PCz2S-PEG demonstrates the best HER, reaching up to 126.9 µmol h-1 in pure water-based photocatalytic solution. Moreover, PCz2S-PEG exhibits comparable performance in seawater-based photocatalytic solution under natural sunlight. In situ SAXS analysis further reveals nucleation-dominated generation of hydrogen nanoclusters with a size of ≈1.5 nm in the HER of PCz2S-PEG under light illumination.

5.
Opt Express ; 32(9): 15078-15092, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859167

RESUMO

Data acquisition, image processing, and image quality are the long-lasting issues for terahertz (THz) 3D reconstructed imaging. Existing methods are primarily designed for 2D scenarios, given the challenges associated with obtaining super-resolution (SR) data and the absence of an efficient SR 3D reconstruction framework in conventional computed tomography (CT). Here, we demonstrate BLIss, a new approach for THz SR 3D reconstruction with sparse 2D data input. BLIss seamlessly integrates conventional CT techniques and variational framework with the core of the adapted Euler-Elastica-based model. The quantitative 3D image evaluation metrics, including the standard deviation of Gaussian, mean curvatures, and the multi-scale structural similarity index measure (MS-SSIM), validate the superior smoothness and fidelity achieved with our variational framework approach compared with conventional THz CT modal. Beyond its contributions to advancing THz SR 3D reconstruction, BLIss demonstrates potential applicability in other imaging modalities, such as X-ray and MRI. This suggests extensive impacts on the broader field of imaging applications.

6.
Opt Express ; 32(7): 11092-11106, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570966

RESUMO

Sub-terahertz (Sub-THz) waves possess exceptional attributes, capable of penetrating non-metallic and non-polarized materials while ensuring bio-safety. However, their practicality in imaging is marred by the emergence of troublesome speckle artifacts, primarily due to diffraction effects caused by wavelengths comparable to object dimensions. In addressing this limitation, we present the Diffuser-aided sub-THz Imaging System (DaISy), which utilizes a diffuser and a focusing lens to convert coherent waves into incoherent counterparts. The cornerstone of our progress lies in a coherence theory-based theoretical framework, pivotal for designing and validating the THz diffuser, and systematically evaluating speckle phenomena. Our experimental results utilizing DaISy reveal substantial improvements in imaging quality and nearly diffraction-limited spatial resolution. Moreover, we demonstrate a tangible application of DaISy in the scenario of security scanning, highlighting the versatile potential of sub-THz waves in miscellaneous fields.

7.
Opt Express ; 32(10): 17763-17774, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858949

RESUMO

Terahertz (THz) tomographic imaging based on time-resolved THz signals has raised significant attention due to its non-invasive, non-destructive, non-ionizing, material-classification, and ultrafast-frame-rate nature for object exploration and inspection. However, the material and geometric information of the tested objects is inherently embedded in the highly distorted THz time-domain signals, leading to substantial computational complexity and the necessity for intricate multi-physics models to extract the desired information. To address this challenge, we present a THz multi-dimensional tomographic framework and multi-scale spatio-spectral fusion Unet (MS3-Unet), capable of fusing and collaborating the THz signals across diverse signal domains. MS3-Unet employs multi-scale branches to extract spatio-spectral features, which are subsequently processed through element-wise adaptive filters and fused to achieve high-quality THz image restoration. Evaluated by geometry-variant objects, MS3-Unet outperforms other peer methods in PSNR and SSIM. In addition to the superior performance, the proposed framework additionally provides high scalable, adjustable, and accessible interface to collaborate with different user-defined models or methods.

8.
Chemistry ; 30(3): e202302416, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-37792811

RESUMO

Transition-metal-catalyzed coupling reactions that involve the direct functionalization of insert C-H bond represent one of the most efficient strategies for forming carbon-carbon bonds. Herein, a palladium-catalyzed intramolecular C-H bond arylation of triaryl phosphates is reported to access seven-membered cyclic biarylphosphonate targets. The reaction is achieved via a unique eight-membered palladacyclic intermediate and shows good functional group compatibility. Meanwhile, the product can be readily converted into other valuable phosphate compounds.

9.
Chemistry ; 30(36): e202401063, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38654592

RESUMO

14,14'-Bidibenzo[a,j]anthracenes (BDBAs) were prepared by iridium-catalyzed annulation of 5,5'-biterphenylene with alkynes. The molecular geometries of overcrowded BDBAs were verified by X-ray crystallography. The two dibenzo[a,j]anthryl moieties are connected through the sterically hindered 14 positions, resulting in highly distorted molecular halves. The conformation with a small twist angle between two molecular halves can minimize steric conflicts between the substituents at 1 and 13 positions and the carbon atoms of the central axis, as well as steric clashes between those substituents. One such example is octafluoro-substituted BDBA, where the interplanar angle between two anthryl moieties is approximately 31° (currently the lowest reported value, cf. 81° in 9,9'-bianthracene). The intramolecular interactions and electronic couplings between two molecular halves resulted in upfield 1H NMR signals, redshifted absorption and emission bands, and a reduced HOMO-LUMO gap. Photodynamic investigations on BDBAs indicated that the formation of the conventional symmetry-breaking charge transfer (SBCT) state was suspended by restricted rocking around the central C-C bond. Such a mechanism associated with this highly constrained conformation was examined for the first time.

10.
Chemistry ; 30(11): e202303523, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-37997021

RESUMO

A new series of biaryls, bi-linear-terphenylenes (BLTPs), were prepared using the tert-butyllithium-mediated cyclization as the key synthetic step. The three-dimensional structures of the studied compounds were verified using X-ray crystallography and DFT calculations. Tetraaryl(ethynyl)-substituted BLTPs are highly crowded molecules, and the internal rotation around the central C-C bond is restricted due to a high barrier (>50 kcal/mol). These structures contain several aryl/terphenylenyl/aryl sandwiches, where the through-space π-π (TSPP) interactions are strongly reflected in the shielding of 1 H NMR chemical shifts, reduction of oxidation potentials, increasing aromaticity of the central six-membered ring and decreasing antiaromaticity of the four-membered rings in a terphenylenyl moiety based on NICS(0) and iso-chemical shielding surfaces. Despite the restricted C-C bond associated intramolecular TSPP interactions for BLTPs in the ground state, to our surprise, the electronic coupling between two linear terphenylenes (LTPs) in BLTPs in the excited state is weak, so that the excited-state behavior is dominated by the corresponding monomeric LTPs. In other words, all BLTPs undergo ultrafast relaxation dynamics via strong exciton-vibration coupling, acting as a blue-light absorber with essentially no emission.

11.
Biotechnol Bioeng ; 121(5): 1518-1531, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38548678

RESUMO

Clostridium tyrobutyricum is an anaerobe known for its ability to produce short-chain fatty acids, alcohols, and esters. We aimed to develop inducible promoters for fine-tuning gene expression in C. tyrobutyricum. Synthetic inducible promoters were created by employing an Escherichia coli lac operator to regulate the thiolase promoter (PCathl) from Clostridium acetobutylicum, with the best one (LacI-Pto4s) showing a 5.86-fold dynamic range with isopropyl ß- d-thiogalactoside (IPTG) induction. A LT-Pt7 system with a dynamic range of 11.6-fold was then created by combining LacI-Pto4s with a T7 expression system composing of RNA polymerase (T7RNAP) and Pt7lac promoter. Furthermore, two inducible expression systems BgaR-PbgaLA and BgaR-PbgaLB with a dynamic range of ~40-fold were developed by optimizing a lactose-inducible expression system from Clostridium perfringens with modified 5' untranslated region (5' UTR) and ribosome-binding site (RBS). BgaR-PbgaLB was then used to regulate the expressions of a bifunctional aldehyde/alcohol dehydrogenase encoded by adhE2 and butyryl-CoA/acetate Co-A transferase encoded by cat1 in C. tyrobutyricum wild type and Δcat1::adhE2, respectively, demonstrating its efficient inducible gene regulation. The regulated cat1 expression also confirmed that the Cat1-catalyzed reaction was responsible for acetate assimilation in C. tyrobutyricum. The inducible promoters offer new tools for tuning gene expression in C. tyrobutyricum for industrial applications.


Assuntos
Clostridium acetobutylicum , Clostridium tyrobutyricum , Clostridium tyrobutyricum/genética , Clostridium tyrobutyricum/metabolismo , Clostridium acetobutylicum/genética , Regiões Promotoras Genéticas/genética , Expressão Gênica , Acetatos/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-38323900

RESUMO

Three microaerophilic bacterial strains, designated SG22T, SG63T and SG29T were isolated from paddy soils in PR China. Cells of these strains were Gram-staining-negative and long rod-shaped. SG22T, SG63T and SG29T showed the highest 16S rRNA gene sequence similarities with the members of the genus Anaeromyxobacter. The results of phylogenetic and phylogenomic analysis also indicated that these strains clustered with members of the genus Anaeromyxobacter. The main respiratory menaquinone of SG22T, SG63T and SG29T was MK-8 and the major fatty acids were iso-C15 : 0, iso-C17 : 0 and C16 : 0. SG22T, SG29T and SG63T not only possessed iron reduction ability but also harboured genes (nifHDK) encoding nitrogenase. The genomic DNA G+C contents of SG22T, SG63T and SG29T ranged from 73.3 to 73.5 %. The average nucleotide identity (ANI) and digital DNA-DNA hybridisation (dDDH) values between SG22T, SG63T and SG29T and the closely related species of the genus Anaeromyxobacter were lower than the cut-off values (dDDH 70 % and ANI 95-96 %) for prokaryotic species delineation. On the basis of these results, strains SG22T, SG63T and SG29T represent three novel species within the genus Anaeromyxobacter, for which the names Anaeromyxobacter terrae sp. nov., Anaeromyxobacter oryzisoli sp. nov. and Anaeromyxobacter soli sp. nov., are proposed. The type strains are SG22T (= GDMCC 1.3185T = JCM 35581T), SG63T (= GDMCC 1.2914T = JCM 35124T) and SG29T (= GDMCC 1.2911T = JCM 35123T).


Assuntos
Myxococcales , Bactérias Fixadoras de Nitrogênio , Compostos Férricos , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , Ácidos Graxos/química , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Nucleotídeos , Solo
13.
J Org Chem ; 89(10): 6729-6739, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38690961

RESUMO

We have developed a Tf2O-mediated approach for the direct amination of either P(O)-OH or P(O)-H reagents with a variety of aliphatic or aromatic amines. Without the requirement of precious metals and toxic reagents, this protocol provides an alternative route to various phosphinamides and phosphoramides. The reaction proceeds under simple and mild conditions and can be effectively scaled up with similar efficiency.

14.
Antonie Van Leeuwenhoek ; 117(1): 68, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630330

RESUMO

In this research, two novel Fe(III)-reducing bacteria, SG10T and SG198T of genus Geothrix, were isolated from the rice field of Fujian Agriculture and Forestry University in Fuzhou, Fujian Province, China. Strains SG10T and SG198T were strictly anaerobic, rod-shaped and Gram-stain-negative. The two novel strains exhibited iron reduction ability, utilizing various single organic acid as the elector donor and Fe(III) as a terminal electron acceptor. Strains SG10T and SG198T showed the highest 16S rRNA sequences similarities to the type strains of Geothrix oryzisoli SG189T (99.0-99.5%) and Geothrix paludis SG195T (99.0-99.7%), respectively. The phylogenetic trees based on the 16S rRNA gene and genome 120 conserved core genes showed that strains SG10T and SG198T belong to the genus Geothrix. Average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the phylogenetic neighbors and the two isolated strains were 86.1-94.3% and 30.7-59.5%, respectively. The major fatty acids were iso-C15:0, anteiso-C15:0, C16:0 and iso-C13:0 3OH, and MK-8 was the main respiratory quinone. According to above results, the two strains were assigned to the genus Geothrix with the names Geothrix campi sp. nov. and Geothrix mesophila sp. nov. Type strains are SG10T (= GDMCC 1.3406 T = JCM 39331 T) and SG198T (= GDMCC 62910 T = KCTC 25635 T), respectively.


Assuntos
Compostos Férricos , Solo , Humanos , Filogenia , RNA Ribossômico 16S/genética , Acidobacteria , Bactérias , DNA
15.
Antonie Van Leeuwenhoek ; 117(1): 79, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38755437

RESUMO

A nitrogen-fixing strain designated SG130T was isolated from paddy soil in Fujian Province, China. Strain SG130T was Gram-staining-negative, rod-shaped, and strictly anaerobic. Strain SG130T showed the highest 16S rRNA gene sequence similarities with the type strains Dendrosporobacter quercicolus DSM 1736T (91.7%), Anaeroarcus burkinensis DSM 6283T (91.0%) and Anaerospora hongkongensis HKU 15T (90.9%). Furthermore, the phylogenetic and phylogenomic analysis also suggested strain SG130T clustered with members of the family Sporomusaceae and was distinguished from other genera within this family. Growth of strain SG130T was observed at 25-45 °C (optimum 30 °C), pH 6.0-9.5 (optimum 7.0) and 0-1% (w/v) NaCl (optimum 0.1%). The quinones were Q-8 and Q-9. The polar lipids were phosphatidylserine (PS), phosphatidylethanolamine (PE), glycolipid (GL), phospholipid (PL) and an unidentified lipid (UL). The major fatty acids (> 10%) were iso-C13:0 3OH (26.6%), iso-C17:1 (15.6%) and iso-C15:1 F (11.4%). The genomic DNA G + C content was 50.7%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain SG130T and the most closely related type strain D. quercicolus DSM 1736T (ANI 68.0% and dDDH 20.3%) were both below the cut-off level for species delineation. The average amino acid identity (AAI) between strain SG130T and the most closely related type strain D. quercicolus DSM 1736T was 63.2%, which was below the cut-off value for bacterial genus delineation (65%). Strain SG130T possessed core genes (nifHDK) involved in nitrogen fixation, and nitrogenase activity (106.38 µmol C2H4 g-1 protein h-1) was examined using the acetylene reduction assay. Based on the above results, strain SG130T is confirmed to represent a novel genus of the family Sporomusaceae, for which the name Azotosporobacter soli gen. nov., sp. nov. is proposed. The type strain is SG130T (= GDMCC 1.3312T = JCM 35641T).


Assuntos
Composição de Bases , DNA Bacteriano , Filogenia , RNA Ribossômico 16S , Microbiologia do Solo , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Técnicas de Tipagem Bacteriana , China , Fosfolipídeos/análise , Fixação de Nitrogênio , Análise de Sequência de DNA , Bactérias Fixadoras de Nitrogênio/classificação , Bactérias Fixadoras de Nitrogênio/genética , Bactérias Fixadoras de Nitrogênio/isolamento & purificação , Bactérias Fixadoras de Nitrogênio/metabolismo
16.
Am J Emerg Med ; 80: 162-167, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608469

RESUMO

INTRODUCTION: The optimal vascular access for patients with out-of-hospital cardiac arrest (OHCA) remains controversial. Increasing evidence supports intraosseous (IO) access due to faster medication administration and higher first-attempt success rates compared to intravenous (IV) access. However, the impact on patient outcomes has been inconclusive. METHODS: This retrospective cohort study in Taoyuan City, Taiwan, from January 1, 2019, to December 31, 2022, included patients aged ≥18 years with non-traumatic OHCA resuscitated by emergency medical technician paramedics (EMT-Ps) with either IVs or IOs for final vascular access. The exclusion criteria were cardiac arrest en route to the hospital and resuscitation during the coronavirus pandemic (from May 1, 2022, to October 31, 2022). The primary and secondary outcomes were sustained ROSC (≥2 h) and cerebral performance category (CPC) 1-2, respectively. Univariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CI) for the primary analysis. Multivariable logistic regression was employed, with variables selected based on a p-value of <0.05 in the univariate analysis. The survival benefits of different insertion sites and subgroups like general ambulance teams (with a composition that includes fewer EMT-Ps and limited experience in using IO access) were also analyzed. RESULTS: A total of 2003 patients were enrolled; 1602 received IV access and 401 IO access. The median patient age was 70 years, and most were male (66.6%). Compared to patients receiving IV access, the adjusted odds ratios (aORs) for primary and secondary outcomes in patients with IOs were 0.83 (95% confidence interval [CI], 0.61-1.11; p = 0.20) and 0.96 (95% CI, 0.39-2.40; p = 0.93), respectively. Different insertion sites showed no outcome differences. In the subgroups of females and patients resuscitated by general ambulance teams, the aORs for sustained ROSC were 0.55 (95% CI, 0.33-0.92; p = 0.02) and 0.62 (95% CI, 0.41-0.94; p = 0.02), respectively. CONCLUSIONS: For patients with OHCA resuscitated by EMT-Ps, IO access was comparable to IV access regarding patient outcomes. However, in females and patients resuscitated by general ambulance teams, IV access might be favorable.


Assuntos
Infusões Intraósseas , Parada Cardíaca Extra-Hospitalar , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Retrospectivos , Infusões Intraósseas/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Taiwan , Reanimação Cardiopulmonar/métodos , Serviços Médicos de Emergência/métodos , Idoso de 80 Anos ou mais
17.
Nucleic Acids Res ; 50(1): 127-148, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34893884

RESUMO

Serratia marcescens is a Gram-negative bacterium of the Enterobacteriaceae family that can produce numbers of biologically active secondary metabolites. However, our understanding of the regulatory mechanisms behind secondary metabolites biosynthesis in S. marcescens remains limited. In this study, we identified an uncharacterized LysR family transcriptional regulator, encoding gene BVG90_12635, here we named psrA, that positively controlled prodigiosin synthesis in S. marcescens. This phenotype corresponded to PsrA positive control of transcriptional of the prodigiosin-associated pig operon by directly binding to a regulatory binding site (RBS) and an activating binding site (ABS) in the promoter region of the pig operon. We demonstrated that L-proline is an effector for the PsrA, which enhances the binding affinity of PsrA to its target promoters. Using transcriptomics and further experiments, we show that PsrA indirectly regulates pleiotropic phenotypes, including serrawettin W1 biosynthesis, extracellular polysaccharide production, biofilm formation, swarming motility and T6SS-mediated antibacterial activity in S. marcescens. Collectively, this study proposes that PsrA is a novel regulator that contributes to antibiotic synthesis, bacterial virulence, cell motility and extracellular polysaccharides production in S. marcescens and provides important clues for future studies exploring the function of the PsrA and PsrA-like proteins which are widely present in many other bacteria.


Assuntos
Proteínas de Bactérias/genética , Biofilmes , Prodigiosina/biossíntese , Serratia marcescens/genética , Fatores de Transcrição/genética , Proteínas de Bactérias/metabolismo , Depsipeptídeos/biossíntese , Movimento , Óperon , Polissacarídeos Bacterianos/biossíntese , Regiões Promotoras Genéticas , Serratia marcescens/metabolismo , Serratia marcescens/patogenicidade , Fatores de Transcrição/metabolismo
18.
Aging Clin Exp Res ; 36(1): 86, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558209

RESUMO

BACKGROUND: Many older adults residing in long-term care often face issues like poor sleep, reduced vitality, and depression. Non-pharmacological approaches, specifically Binaural Beat Music (BBM) and Rhythmic Photic Stimulation (RPS), may alleviate these symptoms, yet their efficacy in this demographic has not been extensively explored. AIMS: This study investigated the effects of combined BBM and RPS interventions on sleep quality, vitality, and depression among older residents with depressive symptoms in long-term care facilities. METHODS: Using a quasi-experimental design, a total of 88 older adults with depressive symptoms from Taiwanese daytime care centers were divided into the BBM with RPS, and Sham groups (44 each). They underwent 20-minute daily sessions of their assigned treatment for two weeks. The BBM with RPS group listened to 10 Hz binaural beat music with 10 Hz photic stimulation glasses, and the Sham group received non-stimulating music and glasses. RESULTS: After the intervention, participants in the BBM with RPS groups showed significant improvements in vitality and depressive mood, with a notable increase in sympathetic nervous system activity. Conversely, the Sham group exhibited significant deterioration in vitality and mental health, with a significant increase in parasympathetic activity. Additionally, compared with the Sham group, the BBM and RPS groups showed significant improvements in vitality, mental health, and depression, with a significant increase in sympathetic nervous activity. CONCLUSION: The two-week intervention suggests that the combination of BBM and RPS, as a non-invasive intervention, can potentially improve vitality, mental health, and depressive mood among older adults in long-term care institutions.


Assuntos
Depressão , Música , Humanos , Idoso , Depressão/terapia , Depressão/diagnóstico , Projetos Piloto , Assistência de Longa Duração , Estimulação Luminosa
19.
J Formos Med Assoc ; 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38914514

RESUMO

BACKGROUND/PURPOSE: Insufficient numbers of peripheral blood stem cells (PBSC) after granulocyte colony-stimulating factor (G-CSF) mobilization occurs in a significant proportion of PBSC collections, often from older age donors. Telomere length (TL) is often used as an indicator of an individual's biological age. This study aimed to investigate the relationship between donors' leukocyte TL and the outcome of G-CSF-induced PBSC mobilization in healthy unrelated donors. METHODS: Donors' leukocyte TLs and the outcome of G-CSF-induced PBSC mobilization, as assessed by pre-harvest CD34+ cell counts, were analyzed in 39 healthy PBSC donors. TL in a non-mobilized general population (n = 90) was included as a control group. G-CSF mobilization effect was categorized into three groups according to pre-harvest CD34+ cell count: poor (≤25/µL, PMD), intermediate (between 25 and 180/µL), and good (≥180/µl, GMD). RESULTS: Leukocyte TL of PBSC donors correlated well with pre-harvest CD34+ cell counts (r = 0.645, p < 0.001). Leukocyte TLs of PMDs (n = 8) were significantly shorter than those of GMDs (n = 9) and non-mobilization controls (p < 0.05). Moreover, all PMD TLs were below the 50th percentile, and 62.5% of PMDs had TLs below the 10th percentile of age-matched control participants. In contrast, no GMD TLs were below the 10th percentile; in fact, 33.3% (3/9) of them were above the 90th percentile. CONCLUSION: Our results indicate that shorter donor leukocyte TL is associated with poor G-CSF-induced PBSC mobilization. TL, which represents a donor's biological age, could be a potential predictor for mobilization outcome.

20.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791180

RESUMO

Chondrosarcoma is a malignant bone tumor that arises from abnormalities in cartilaginous tissue and is associated with lung metastases. Lymphangiogenesis plays an essential role in cancer metastasis. Visfatin is an adipokine reported to enhance tumor metastasis, but its relationship with VEGF-D generation and lymphangiogenesis in chondrosarcoma remains undetermined. Our results from clinical samples reveal that VEGF-D levels are markedly higher in chondrosarcoma patients than in normal individuals. Visfatin stimulation promotes VEGF-D-dependent lymphatic endothelial cell lymphangiogenesis. We also found that visfatin induces VEGF-D production by activating HIF-1α and reducing miR-2277-3p generation through the Raf/MEK/ERK signaling cascade. Importantly, visfatin controls chondrosarcoma-related lymphangiogenesis in vivo. Therefore, visfatin is a promising target in the treatment of chondrosarcoma lymphangiogenesis.


Assuntos
Neoplasias Ósseas , Condrossarcoma , Subunidade alfa do Fator 1 Induzível por Hipóxia , Linfangiogênese , MicroRNAs , Nicotinamida Fosforribosiltransferase , Fator D de Crescimento do Endotélio Vascular , Humanos , Condrossarcoma/metabolismo , Condrossarcoma/genética , Condrossarcoma/patologia , Linfangiogênese/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Nicotinamida Fosforribosiltransferase/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Fator D de Crescimento do Endotélio Vascular/metabolismo , Fator D de Crescimento do Endotélio Vascular/genética , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Neoplasias Ósseas/genética , Animais , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Camundongos , Citocinas/metabolismo , Masculino , Feminino , Sistema de Sinalização das MAP Quinases
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