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1.
Elife ; 132024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775133

RESUMEN

Tissue-clearing and labeling techniques have revolutionized brain-wide imaging and analysis, yet their application to clinical formalin-fixed paraffin-embedded (FFPE) blocks remains challenging. We introduce HIF-Clear, a novel method for efficiently clearing and labeling centimeter-thick FFPE specimens using elevated temperature and concentrated detergents. HIF-Clear with multi-round immunolabeling reveals neuron circuitry regulating multiple neurotransmitter systems in a whole FFPE mouse brain and is able to be used as the evaluation of disease treatment efficiency. HIF-Clear also supports expansion microscopy and can be performed on a non-sectioned 15-year-old FFPE specimen, as well as a 3-month formalin-fixed mouse brain. Thus, HIF-Clear represents a feasible approach for researching archived FFPE specimens for future neuroscientific and 3D neuropathological analyses.


Asunto(s)
Encéfalo , Formaldehído , Neuronas , Adhesión en Parafina , Fijación del Tejido , Animales , Adhesión en Parafina/métodos , Ratones , Fijación del Tejido/métodos , Neuronas/fisiología , Fijadores/química
2.
Environ Int ; 188: 108778, 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38815467

RESUMEN

With the discovery of evidence that many endocrine-disrupting chemicals (EDCs) in the environment influence human health, their toxic effects and mechanisms have become a hot topic of research. However, investigations into their endocrine-disrupting toxicity under combined binary exposure, especially the molecular mechanism of combined effects, have rarely been documented. In this study, two typical EDCs, perfluorooctanoic acid (PFOA) and 4-hydroxybenzophenone (4-HBP), were selected to examine their combined effects and molecular mechanism on MCF-7 cell proliferation at environmentally relevant exposure concentrations. We have successfully established a model to evaluate the binary combined toxic effects of endocrine disruptors, presenting combined effects in a simple and direct way. Results indicated that the combined effect changed from additive to synergistic from 1.25 × 10-8 M to 4 × 10-7 M. Metabolomics analyses suggested that exposure to PFOA and 4-HBP caused significant alterations in purine metabolism, arginine, and proline metabolism and had superimposed influences on metabolism. Enhanced combined effects were observed in glycine, serine, and threonine metabolic pathways compared to exposure to PFOS and 4-HBP alone. Additionally, the differentially expressed genes (DEGs) are primarily involved in Biological Processes, especially protein targeting the endoplasmic reticulum, and significantly impact the oxidative phosphorylation and thermogenesis-related KEGG pathway. By integrating metabolome and transcriptome analyses, PFOA and 4-HBP regulate purine metabolism, the TCA cycle, and endoplasmic reticulum protein synthesis in MCF-7 cells via mTORC1, which provides genetic material, protein, and energy for cell proliferation. Furthermore, molecular docking confirmed the ability of PFOA and 4-HBP to stably bind the estrogen receptor, indicating that they have different binding pockets. Collectively, these findings will offer new insights into understanding the mechanisms by which EDCs produce combined toxicity.

3.
Commun Chem ; 7(1): 108, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734809

RESUMEN

Immobilization of graphene quantum dots (GQDs) on a solid support is crucial to prevent GQDs from aggregation in the form of solid powder and facilitate the separation and recycling of GQDs after use. Herein, spatially dispersed GQDs are post-synthetically coordinated within a two-dimensional (2D) and water-stable zirconium-based metal-organic framework (MOF). Unlike pristine GQDs, the obtained GQDs immobilized on 2D MOF sheets show photoluminescence in both suspension and dry powder. Chemical and photoluminescent stabilities of MOF-immobilized GQDs in water are investigated, and the use of immobilized GQDs in the photoluminescent detection of copper ions is demonstrated. Findings here shed the light on the use of 2D MOFs as a platform to further immobilize GQDs with various sizes and distinct chemical functionalities for a range of applications.

4.
Angew Chem Int Ed Engl ; : e202407702, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38751355

RESUMEN

The current bottleneck in the development of efficient photocatalysts for hydrogen evolution is the limited availability of high-performance acceptor units. Over the past nine years, dibenzo[b,d]thiophene sulfone (DBS) has been the preferred choice for the acceptor unit. Despite extensive exploration of alternative structures as potential replacements for DBS, a superior substitute remains elusive. In this study, a symmetry-breaking strategy was employed on DBS to develop a novel acceptor unit, BBTT-1SO. The asymmetric structure of BBTT-1SO proved beneficial for increasing multiple moment and polarizability. BBTT-1SO-containing polymers showed higher efficiencies for hydrogen evolution than their DBS-containing counterparts by up to 166%. PBBTT-1SO exhibited an excellent hydrogen evolution rate (HER) of 222.03 mmol g-1 h-1 and an apparent quantum yield of 27.5% at 500 nm. Transient spectroscopic studies indicated that the BBTT-1SO-based polymers facilitated electron polaron formation, which explains their superior HERs. PBBTT-1SO also showed 14% higher HER in natural seawater splitting than that in deionized water splitting. Molecular dynamics simulations highlighted the enhanced water-PBBTT-1SO polymer interactions in salt-containing solutions. This study presents a pioneering example of a substitute acceptor unit for DBS in the construction of high-performance photocatalysts for hydrogen evolution.

5.
Antonie Van Leeuwenhoek ; 117(1): 79, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38755437

RESUMEN

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).


Asunto(s)
Composición de Base , ADN Bacteriano , Filogenia , ARN Ribosómico 16S , Microbiología del Suelo , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Ácidos Grasos/análisis , Ácidos Grasos/metabolismo , Técnicas de Tipificación Bacteriana , China , Fosfolípidos/análisis , Fijación del Nitrógeno , Análisis de Secuencia de ADN , Bacterias Fijadoras de Nitrógeno/clasificación , Bacterias Fijadoras de Nitrógeno/genética , Bacterias Fijadoras de Nitrógeno/aislamiento & purificación , Bacterias Fijadoras de Nitrógeno/metabolismo
6.
PLoS One ; 19(5): e0301984, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38771833

RESUMEN

BACKGROUND: The prevalence of burnout among live streamers remains largely unknown. This study aims to investigate the prevalence and factors associated with burnout among Chinese live streamers. METHODS: A cross-sectional study recruited 343 full-time live streamers from 3 companies in Changsha city. Socio-demographic and occupational characteristics were collected using self-designed items. Job stress was assessed using the Job Content Questionnaire (JCQ-22), while supervisor and coworker support were evaluated using the last 8 items of the JCQ-22. Burnout was assessed using the 17-item Chinese version of the Maslach Burnout Inventory-Human Services Survey (MBI-HSS). RESULTS: Our findings revealed that 30.6% of live streamers experienced burnout. Lower levels of education (OR = 2.65 and 3.37, p = 0,005 and 0.003), higher monthly income (OR = 10.56 and 11.25, both p = 0.003), being an entertainment-oriented streamer (OR = 2.13, p = 0.028), continuous walking during live streams (OR = 2.81, p = 0.006), significant drop in follower count (OR = 2.65, P = 0.006), live streaming during the daytime (OR = 3.75, p = 0.001), and higher support from supervisors and coworkers (OR = 3.66, p = 0.001) were positively associated with burnout. However, the effects of education and drop in followers on burnout were not significant in the multivariate logistic models (p = 0.321 and 0.988). CONCLUSIONS: Burnout among Chinese live streamers is associated with income, being an entertainment streamer, engaging in continuous walking during live streams, conducting live streams during the daytime, and experiencing excessive support from supervisors and coworkers.


Asunto(s)
Agotamiento Profesional , Humanos , Femenino , Masculino , Adulto , China/epidemiología , Estudios Transversales , Prevalencia , Agotamiento Profesional/epidemiología , Agotamiento Profesional/psicología , Persona de Mediana Edad , Encuestas y Cuestionarios
7.
J Org Chem ; 89(10): 6729-6739, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38690961

RESUMEN

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.

8.
Int J Mol Sci ; 25(10)2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38791180

RESUMEN

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.


Asunto(s)
Neoplasias Óseas , Condrosarcoma , Subunidad alfa del Factor 1 Inducible por Hipoxia , Linfangiogénesis , MicroARNs , Nicotinamida Fosforribosiltransferasa , Factor D de Crecimiento Endotelial Vascular , Humanos , Condrosarcoma/metabolismo , Condrosarcoma/genética , Condrosarcoma/patología , Linfangiogénesis/genética , MicroARNs/genética , MicroARNs/metabolismo , Nicotinamida Fosforribosiltransferasa/metabolismo , Nicotinamida Fosforribosiltransferasa/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Factor D de Crecimiento Endotelial Vascular/metabolismo , Factor D de Crecimiento Endotelial Vascular/genética , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Neoplasias Óseas/genética , Animales , Regulación Neoplásica de la Expresión Génica , Línea Celular Tumoral , Ratones , Citocinas/metabolismo , Masculino , Femenino , Sistema de Señalización de MAP Quinasas
10.
Aging Clin Exp Res ; 36(1): 86, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38558209

RESUMEN

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.


Asunto(s)
Depresión , Música , Humanos , Anciano , Depresión/terapia , Depresión/diagnóstico , Proyectos Piloto , Cuidados a Largo Plazo , Estimulación Luminosa
11.
Int Immunopharmacol ; 132: 112016, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38593506

RESUMEN

Osteoarthritis (OA) is a low-grade inflammatory joint illness in which monocytes migrate and infiltrate synovial tissue, differentiating into the pro-inflammatory M1 macrophage phenotype. IL-17 is a proinflammatory mediator principally generated by Th17 cells, which is elevated in OA patients; nevertheless, investigators have yet to elucidate the function of IL-17 in M1 polarization during OA development. Our analysis of clinical tissues and results from the open online dataset discovered that the level of M1 macrophage markers is elevated in human OA tissue samples than in normal tissue. High-throughput screening demonstrated that MCP-1 is a potential candidate factor after IL-17 treatment in OA synovial fibroblasts (OASFs). Immunohistochemistry data revealed that the level of MCP-1 is higher in humans and mice with OA than in normal tissues. IL-17 stimulation facilitates MCP-1-dependent macrophage polarization to the M1 phenotype. It also appears that IL-17 enhances MCP-1 synthesis in human OASFs, enhancing monocyte migration via the JAK and STAT3 signaling cascades. Our findings indicate the IL-17/MCP-1 axis as a novel strategy for the remedy of OA.


Asunto(s)
Movimiento Celular , Quimiocina CCL2 , Interleucina-17 , Macrófagos , Monocitos , Osteoartritis , Animales , Humanos , Masculino , Ratones , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Quimiocina CCL2/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/inmunología , Interleucina-17/metabolismo , Macrófagos/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Monocitos/inmunología , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Osteoartritis/inmunología , Transducción de Señal , Factor de Transcripción STAT3/metabolismo , Membrana Sinovial/inmunología , Membrana Sinovial/patología
12.
Antonie Van Leeuwenhoek ; 117(1): 68, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630330

RESUMEN

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.


Asunto(s)
Compuestos Férricos , Suelo , Humanos , Filogenia , ARN Ribosómico 16S/genética , Acidobacteria , Bacterias , ADN
13.
Opt Express ; 32(7): 11092-11106, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38570966

RESUMEN

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.

14.
Am J Emerg Med ; 80: 162-167, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38608469

RESUMEN

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.


Asunto(s)
Infusiones Intraóseas , Paro Cardíaco Extrahospitalario , Humanos , Paro Cardíaco Extrahospitalario/terapia , Estudios Retrospectivos , Infusiones Intraóseas/métodos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Taiwán , Reanimación Cardiopulmonar/métodos , Servicios Médicos de Urgencia/métodos , Anciano de 80 o más Años
15.
Chemistry ; : e202401063, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654592

RESUMEN

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.

17.
Biotechnol Bioeng ; 121(5): 1518-1531, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38548678

RESUMEN

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.


Asunto(s)
Clostridium acetobutylicum , Clostridium tyrobutyricum , Clostridium tyrobutyricum/genética , Clostridium tyrobutyricum/metabolismo , Clostridium acetobutylicum/genética , Regiones Promotoras Genéticas/genética , Expresión Génica , Acetatos/metabolismo
18.
J Orthop Res ; 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520666

RESUMEN

Osteoarthritis (OA) is a common degenerative joint disease, and subchondral osteosclerosis is an important pathological change that occurs in its late stages. Cardamonin (CD) is a natural flavonoid isolated from Alpinia katsumadai that has anti-inflammatory activity. The objectives of this study were to investigate the therapeutic effects and potential mechanism of CD in regulating OA subchondral osteosclerosis at in vivo and in vitro settings. Eight-week-old male C57BL/6J mice were randomly divided into four groups: sham operation, anterior cruciate ligament transection (ACLT)-induced OA model, low-dose and high-dose CD treated ACLT-OA model groups. Histological assessment and immunohistochemical examinations for chondrocyte metabolism-related markers metalloproteinase-13, ADAMTS-4, Col II, and Sox-9 were performed. Microcomputed tomography was used to assess the sclerosis indicators in subchondral bone. Further, MC3T3-E1 (a mouse calvarial preosteoblast cell line) cells were treated with various concentrations of CD to reveal the influence and potential molecular pathways of CD in osteogenic differentiations. Animal studies suggested that CD alleviated the pathological changes in OA mice such as maintaining integrity and increasing the thickness of hyaline cartilage, decreasing the thickness of calcified cartilage, decreasing the Osteoarthritis Research Society International score, regulating articular cartilage metabolism, and inhibiting subchondral osteosclerosis. In vitro investigation indicated that CD inhibited alkaline phosphatase expression and production of calcium nodules during osteogenic differentiation of MC3T3-E1 cells. In addition, CD inhibited the expression of osteogenic differentiation-related indicators and Wnt/ß-catenin pathway-related proteins. In conclusion, CD inhibits osteogenic differentiation by downregulating Wnt/ß-catenin signaling and alleviating subchondral osteosclerosis in a mouse model of OA.

19.
Artículo en Inglés | MEDLINE | ID: mdl-38454131

RESUMEN

Hematopoietic stem cell (HSC) transplantation, using either bone marrow (BM) or peripheral blood stem cells (PBSC), is a well-established therapy for various hematologic and non-hematologic diseases. However, the long-term health outcomes after HSC donation remain a major concern for several potential donors. Thus, we aimed to conduct a matched cohort study of 5003 unrelated donors (1099 BM and 3904 PBSC) and randomly selected 50,030 matched controls based on age, sex, and resident area from the donor registry between 1998 and 2018. The medical insurance claims of all the participants were retrieved from the Taiwan National Health and Welfare Data Science Center after de-identification. Our findings revealed no differences in the incidence of cancer, death, and catastrophic diseases between HSC donors and matched healthy participants during long-term follow-up. Kaplan-Meier curves depicting the cumulative incidence of cancer and overall mortality throughout the follow-up period also demonstrated similar outcomes between donors and non-donors. In conclusion, our results indicate that HSC donation, whether through BM or PBSC, is safe and not associated with an increased risk of cancer, death, or catastrophic diseases. These findings provide valuable information for counseling potential HSC donors and for long-term management of HSC donor health.

20.
Angew Chem Int Ed Engl ; 63(16): e202401103, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38412017

RESUMEN

Singlet fission (SF) holds great promise for current photovoltaic technologies, where tetracenes, with their relatively high triplet energies, play a major role for application in silicon-based solar cells. However, the SF efficiencies in tetracene dimers are low due to the unfavorable energetics of their singlet and triplet energy levels. In the solid state, tetracene exhibits high yields of triplet formation through SF, raising great interest about the underlying mechanisms. To address this discrepancy, we designed and prepared a novel molecular system based on a hexaphenylbenzene core decorated with 2 to 6 tetracene chromophores. The spatial arrangement of tetracene units, induced by steric hindrance in the central part, dictates through-space coupling, making it a relevant model for solid-state chromophore organization. We then revealed a remarkable increase in SF quantum yield with the number of tetracenes, reaching quantitative (196 %) triplet pair formation in hexamer. We observed a short-lived correlated triplet pair and limited magnetic effects, indicating ineffective triplet dissociation in these through-space coupled systems. These findings emphasize the crucial role of the number of chromophores involved and the interchromophore arrangement for the SF efficiency. The insights gained from this study will aid designing more efficient and technology-compatible SF systems for applications in photovoltaics.

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