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1.
Sci Total Environ ; 927: 172337, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608908

RESUMO

Fire emissions in Southeast Asia transported to southern China every spring (March-May), influencing not only the air quality but also the weather and climate. However, the multi-year variations and magnitude of this impact on aerosol radiation forcing in southern China remain unclear. Here, we quantified the multi-year contributions of fire emissions in Indo-China Peninsula (ICP) region to aerosol radiation forcing in the various southern Chinese provinces during the fire season (March-May) of 2013-2019 combining the 3-dimension chemical transport model and the Column Radiation Model (CRM) simulations. The models' evaluations showed they reasonably capture the temporal and spatial distribution of surface aerosol concentrations and column aerosol optical properties over the study regions. The fire emissions over the ICP region were found to increase the aerosol optical depth (AOD) value by 0.1 (15 %) and reduce the single scattering albedo (SSA) in three southern regions of China (Yunnan-YN, Guangxi-GX, and Guangdong-GD from west to east), owing to increases in the proportions of black carbon (BC, 0.4 % ± 0.1 %) and organic carbon (OC, 3.0 % ± 0.9 %) within the aerosol compositions. The transported smoke aerosols cooled surface but heated the atmosphere in the southern China regions, with the largest mean reduction of -5 Wm-2 (-3 %) in surface shortwave radiation forcing and the maximum daily contributions of about -15 Wm-2 (-15 %) to the atmosphere radiation forcing in the GX region, followed by the GD and YN regions. The impacts of ICP fire emissions on aerosol optical and radiative parameters declined during 2013-2019, with the highest rate of 0.393 ± 0.478 Wm-2 yr-1 in the GX for the shortwave radiation forcing in the atmosphere. Besides, their yearly changes in the contribution were consistent with the annual fire emissions in the ICP region. Such strong radiative perturbations of ICP fire emissions were expected to influence regional meteorology in southern China and should be considered in the climate simulations.

3.
J Math Biol ; 88(6): 62, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38615293

RESUMO

The design of optimized non-pharmaceutical interventions (NPIs) is critical to the effective control of emergent outbreaks of infectious diseases such as SARS, A/H1N1 and COVID-19 and to ensure that numbers of hospitalized cases do not exceed the carrying capacity of medical resources. To address this issue, we formulated a classic SIR model to include a close contact tracing strategy and structured prevention and control interruptions (SPCIs). The impact of the timing of SPCIs on the maximum number of non-isolated infected individuals and on the duration of an infectious disease outside quarantined areas (i.e. implementing a dynamic zero-case policy) were analyzed numerically and theoretically. These analyses revealed that to minimize the maximum number of non-isolated infected individuals, the optimal time to initiate SPCIs is when they can control the peak value of a second rebound of the epidemic to be equal to the first peak value. More individuals may be infected at the peak of the second wave with a stronger intervention during SPCIs. The longer the duration of the intervention and the stronger the contact tracing intensity during SPCIs, the more effective they are in shortening the duration of an infectious disease outside quarantined areas. The dynamic evolution of the number of isolated and non-isolated individuals, including two peaks and long tail patterns, have been confirmed by various real data sets of multiple-wave COVID-19 epidemics in China. Our results provide important theoretical support for the adjustment of NPI strategies in relation to a given carrying capacity of medical resources.


Assuntos
COVID-19 , Doenças Transmissíveis Emergentes , Vírus da Influenza A Subtipo H1N1 , Humanos , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/prevenção & controle , COVID-19/epidemiologia , COVID-19/prevenção & controle , China/epidemiologia , Busca de Comunicante
4.
Enzyme Microb Technol ; 178: 110440, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38574422

RESUMO

The manufacturing of indigo naturalis requires prolonged leaf soaking and lime stirring; the resulting indigo purity is less than 3.00% and the yield of indigo (measured in stems and leaves weight) is less than 0.50%, making it unsuitable for use in industrial procedures like printing and dyeing. An enzymatic method of creating indigo without the requirement for lime was investigated in order to generate high purity indigo. Single factor tests were performed to optimize the enzymatic preparation conditions. The findings showed that 60 °C, pH 5.5, 200 mL of leaves extract containing 0.45 mg/mL indican, and a 4:1 ratio of the acidic cellulose (activity: 9000 U/mL, liquid) to indican were the ideal parameters for enzymatic preparation. The yield of indigo was 40.32%, and the contents of indigo and indirubin were 37.37% and 2.30%, respectively. MALDI-TOF-MS in positive ion mode and UPLC-Q-TOF-MS in both positive and negative ion modes were used to analyze indigo extracts from Baphicacanthus cusia(Nees) Bremek by enzymatic preparation. It has been discovered that 13 alkaloids, 5 organic acids, 3 terpenoids, 3 steroids, 2 flavones, and 7 other compounds are present in indigo extracts. The presence of the indigo, indirubin, isorhamnetin, tryptanthrin, indigodole B, and indigodole C determined by UPLC-Q-TOF-MS was verified by MALDI-TOF-MS analysis. The enzymatic preparation of indigo extracts kept the same chemical makeup as conventional indigo naturalis. Thermal analysis and SEM morphology were used to confirm that there was no lime in the indigo extract. During the enzymatic process, Baphicacanthus cusia (Nees) Bremek was employed more effectively, increasing the yield and purity of indigo.

5.
Opt Express ; 32(7): 10962-10978, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570957

RESUMO

We propose a novel methane leakage rate remote sensor that combines a single-photon avalanche diode detector with a near-infrared 1653.7 nm low-power laser. The proposed M sequence and triangle wave signal modulation method simultaneously realizes the detection of methane leakage and target point clouds. Innovatively, the sensor's methane concentration and leakage rate quantification ability were simulated by combining the Gaussian plume diffusion model and the Risley prism. The effects of the prism rotation ratio, wind speed, leakage rate, atmospheric stability (AS), target reflectivity, signal averaging period, and concentration spatial interpolation method on leakage rate are discussed. When plume methane concentrations reduce from 10,000 to 500 ppm·m, the relative concentration bias rise from 1% to 30%, the absolute concentration bias is approximately 100 ppm·m. Two spatial concentration interpolation methods introduced leakage rate bias ranging from 6%-25%. For a low AS, the leakage rate bias under the cubic interpolation method was small (approximately 1.6%). In addition, when the initial leakage rate increased from 100 to 1,000 mg/s, the leakage rate bias was approximately 20% smaller.

6.
ACS Appl Electron Mater ; 6(3): 1530-1541, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38558951

RESUMO

Transition metal dichalcogenide (TMD) moiré superlattices have emerged as a significant area of study in condensed matter physics. Thanks to their superior optical properties, tunable electronic band structure, strong Coulomb interactions, and quenched electron kinetic energy, they offer exciting avenues to explore correlated quantum phenomena, topological properties, and light-matter interactions. In recent years, scanning tunneling microscopy (STM) has made significant impacts on the study of these fields by enabling intrinsic surface visualization and spectroscopic measurements with unprecedented atomic scale detail. Here, we spotlight the key findings and innovative developments in imaging and characterization of TMD heterostructures via STM, from its initial implementation on the in situ grown sample to the latest photocurrent tunneling microscopy. The evolution in sample design, progressing from a conductive to an insulating substrate, has not only expanded our control over TMD moiré superlattices but also promoted an understanding of their structures and strongly correlated properties, such as the structural reconstruction and formation of generalized two-dimensional Wigner crystal states. In addition to highlighting recent advancements, we outline upcoming challenges, suggest the direction of future research, and advocate for the versatile use of STM to further comprehend and manipulate the quantum dynamics in TMD moiré superlattices.

7.
Heliyon ; 10(7): e28412, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38560128

RESUMO

Cysteine and serine-rich nuclear protein 1 (CSRNP1) has shown prognostic significance in various cancers, but its role in non-small cell lung cancer (NSCLC) remains elusive. We investigated CSRNP1 expression in NSCLC cases using bioinformatics tools from the GEO public repository and validated our findings through RT-qPCR in tumor and adjacent normal tissues. KEGG and GO enrichment analyses were employed to unveil the significant deregulation in signaling pathways. Additionally, clinical significance of CSRNP1 in NSCLC was determined through receiver operating curve (ROC) analysis, and its impact on survival was assessed using Kaplan-Meier analysis. To explore the functional impact of CSRNP1, we silenced its expression in NSCLC cells and assessed the effects on cell viability, migration, and invasion using MTT, Transwell, and wound-healing assays, respectively. Additionally, we investigated the influence of CSRNP1 silencing on the phosphorylation patterns of critical signaling proteins such as p53, p-Akt, and p-MDM2. Our results demonstrated significantly lower CSRNP1 expression in NSCLC tumor tissues (P < 0.01). ROC analysis indicated that NSCLC patients with high CSRNP1 expression exhibited extended overall survival and disease-free survival. Furthermore, CSRNP1 silencing promoted NSCLC cells viability, migration, and invasion (P < 0.05). Mechanistically, CSRNP1 silencing led to increased phosphorylation of AKT and MDM2, along with a concurrent reduction in p53 protein expression, suggesting its impact on NSCLC through deregulated cell cycle processes. In conclusion, our study underscores the significance of CSRNP1 in NSCLC pathogenesis, offering insights for targeted therapeutic interventions of NSCLC.

8.
Mitochondrial DNA B Resour ; 9(4): 428-431, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38586506

RESUMO

Plumbago zeylanica L. 1753 is a medicinally-important herb in family Plumbaginaceae. In this study, we assembled and reported the complete chloroplast genome of P. zeylanica. The plastome of P. zeylanica was 169,178 bp, including a large single-copy region of 92,135 bp, a small single-copy region (SSC) of 13,455 bp and a pair of inverted repeat regions (IRs) of 31,794 bp. It contained 124 genes, including 79 protein-coding genes, 37 tRNA genes and eight rRNA genes. Phylogenetic analysis showed that P. zeylanica formed a close relationship with P. auriculata in Plumbago. The first complete chloroplast genome report of P. zeylanica providing an opportunity to explore the genetic diversity, and would be also helpful in the species identification and conservation.

9.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167158, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38588780

RESUMO

OBJECTIVES: Diabetic cardiomyopathy (DCM) is the leading cause of mortality in type 2 diabetes mellitus (T2DM) patients, with its underlying mechanisms still elusive. This study aims to investigate the role of cholesterol-25-monooxygenase (CH25H) in T2DM induced cardiomyopathy. METHODS: High fat diet combined with streptozotocin (HFD/STZ) were used to establish a T2DM model. CH25H and its product 25-hydroxycholesterol (25HC) were detected in the hearts of T2DM model. Gain- or loss-of-function of CH25H were performed by receiving AAV9-cTNT-CH25H or CH25H knockout (CH25H-/-) mice with HFD/STZ treatment. Cardiac function was evaluated using echocardiography, and cardiac tissues were collected for immunoblot analysis, histological assessment and quantitative polymerase chain reaction (qPCR). Mitochondrial morphology and function were evaluated using transmission electron microscopy (TEM) and Seahorse XF Cell Mito Stress Test Kit. RNA-sequence analysis was performed to determine the molecular changes associated with CH25H deletion. RESULTS: CH25H and 25HC were significantly decreased in the hearts of T2DM mice. CH25H-/- mice treated with HFD/STZ exhibited impaired mitochondrial function and structure, increased lipid accumulation, and aggregated cardiac dysfunction. Conversely, T2DM mice receiving AAV9-CH25H displayed cardioprotective effects. Mechanistically, RNA sequencing and qPCR analysis revealed that CH25H deficiency decreased peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) and its target gene expression. Additionally, administration of ZLN005, a potent PGC-1α activator, partially protected against high glucose and palmitic acid induced mitochondria dysfunction and lipid accumulation in vitro. CONCLUSION: Our study provides compelling evidence supporting the protective role of CH25H in T2DM-induced cardiomyopathy. Furthermore, the regulation of PGC-1α may be intricately involved in this cardioprotective process.

10.
Sci Rep ; 14(1): 8845, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632254

RESUMO

Observational studies have found a potential bidirectional positive association between multiple sclerosis and psoriasis, but these studies are susceptible to confounding factors. We examined the directionality of causation using Mendelian randomization and estimated the genetic correlation using the linkage disequilibrium score. We performed Mendelian randomization analysis using large-scale genome-wide association studies datasets from the International Multiple Sclerosis Genetics Consortium (IMSGC, 115,803 individuals of European ancestry) and FinnGen (252,323 individuals of European ancestry). We selected several Mendelian randomization methods including causal analysis using summary effect (CAUSE), inverse variance-weighted (IVW), and pleiotropy-robust methods. According to CAUSE and IVW the genetic liability to MS reduces the risk of psoriasis (CAUSE odds ratio [OR] 0.93, p = 0.045; IVW OR 0.93, p = 2.51 × 10-20), and vice versa (CAUSE OR 0.72, p = 0.001; IVW OR 0.71, p = 4.80 × 10-26). Pleiotropy-robust methods show the same results, with all p-values < 0.05. The linkage disequilibrium score showed no genetic correlation between psoriasis and MS (rg = - 0.071, p = 0.2852). In summary, there is genetic evidence that MS reduces the risk of psoriasis, and vice versa.


Assuntos
Esclerose Múltipla , Psoríase , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Causalidade
11.
Phys Med Biol ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640917

RESUMO

PURPOSE: Fast kV-switching (FKS) and dual-layer flat-panel detector (DL-FPD) technologies have been actively studied as promising dual-energy solutions for FPD-based cone-beam computed tomography (CBCT). However, CBCT spectral imaging is known to face challenges in obtaining accurate and robust material discrimination performance due to the limited energy separation. To further improve CBCT spectral imaging capability, this work aims to promote a source-detector joint spectral imaging solution which takes advantages of both FKS and DL-FPD, and to conduct a feasibility study on the first tabletop CBCT system with the joint spectral imaging capability developed. Methods: A noise performance analysis using the Cramér-Rao lower bound (CRLB) method is conducted. The CRLB for basis material after a projection-domain material decomposition is derived, followed by a set of numerical calculations of CRLBs, for the FKS, the DL-FPD and the joint solution, respectively. In this work, the first FKS and DL-FPD jointly enabled multi-energy tabletop CBCT system, to the best of our knowledge, has been developed in our laboratory. To evaluate its spectral imaging performance, a set of physics experiments are conducted, where the multi-energy and head phantoms are scanned using the 80/105/130kVp switching pairs and projection data are collected using a prototype DL-FPD. To compensate for the slightly angular mismatch between the low- and high-energy projections in FKS, a dual-domain projection completion scheme is implemented. Afterwards material decomposition is carried out by using the maximum-likelihood method, followed by reconstruction of basis material and virtual monochromatic images. Results: The numerical simulations show that the joint solution can lead to a significant improvement in energy separation and lower noise levels. The physics experiments confirmed the feasibility and superiority of the joint spectral imaging, whose CNRs of the multi-energy phantom were boosted by an average improvement of 21.9%, 20.4% for water and 32.8%, 62.8% for iodine when compared with that of the FKS and DL-FPD in fan-beam and cone-beam experiments, respectively. Conclusions: A feasibility study of the joint spectral imaging for CBCT by utilizing both the FKS and DL-FPD was conducted, with the first tabletop CBCT system having such a capability being developed, which exhibits improved spectral imaging performance as expected.

12.
Chemosphere ; 357: 141938, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38631498

RESUMO

The peroxynitrite photocatalytic degradation system was considered a green, convenient, and efficient water treatment process, but not satisfying against some antibiotics, e.g. sulfonamides (SAs). To improve the photocatalytic degradation efficiency of SAs, sulfur was introduced to a magnetic Fe-MOF (Fe-metal organic framework) Prussian blue analog to achieve a heteroatomic material CuFeO@S, which was applied in heterogeneous visible light photo-assisted catalytic process with persulfate (PS) as an oxidant. The characterization results of CuFeO@S by XRD and XPS confirmed the presence of Fe3O4 (for magnetic separation), Cu+ (for activation of PS) and S2- (for narrowing the energy band and prolonging the lifetime of photo-generated electronics). Through systematic optimization of reaction conditions in CuFeO@S + PS + hv system, efficient degradation of four tested SAs was achieved in 30 min (removal rate of 97-100% for the tested 4 SAs). Moreover, the material could be magnetically recycled and reused for over 7 cycles with a removal rate of >90% for sulfamerazine. Furthermore, the removal rate of sulfamerazine in pond water reached 99% at a mineralization rate of about 34% (decrease in total organic matter), demonstrating its potential in the treatment of antibiotic-containing wastewater.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38639634

RESUMO

Background: Currently, conventional closed thoracic drainage for pneumothorax involves a painful procedure with a higher risk and wider (1~1.5 cm) incision. Minimally invasive catheterized drainage techniques are urgently needed to address this challenge. Objective: This retrospective study aims to observe the effects of conventional closed thoracic drainage with deep venous catheterization drainage techniques on pneumothorax patients. Design: It was a retrospective study. Setting: This study was conducted at Huaian No.1 People's Hospital, Affiliated with Nanjing Medical University. Participants: A total of 105 pneumothorax patients who underwent conventional closed thoracic drainage (CCTD) or deep venous catheterization drainage technique (DVCDT) procedures at the hospital from 1st February 2020 to 30th October 2022 were selected. Interventions: Patients received either CCTD or DVCDT. Primary Outcome Measures: Included: (1) clinical variables; (2) catheterization procedure-related features; and (3) visual analogue scale (VAS) scores from pneumothorax patients. Results: Both conventional closed thoracic drainage and deep venous catheterization drainage techniques were successfully performed in all 105 (100%) patients, comprising 67 (63.8%) spontaneous pneumothorax, 20 (19%) iatrogenic pneumothorax, and 18 (17.1%) traumatic pneumothorax cases. Significant differences were observed between the enrolled spontaneous pneumothorax and traumatic pneumothorax patients in the two groups (CCTD and DVCDT) (P = .01 and P < .0001). Additionally, 55 (52.4%) patients underwent deep venous catheterization, while 50 (47.6%) patients underwent conventional closed thoracic drainage. The deep venous catheterization insertion procedure had a shorter mean timing (7.51±1.66 min) compared to the conventional closed thoracic drainage procedure (12.44±1.73 min) (P < .0001). Furthermore, VAS scores were significantly lower in pneumothorax patients undergoing deep venous catheterization (2.1±0.99) compared to conventional closed thoracic drainage (5.1±0.81) (P < .0001). Conclusion: Deep venous thoracic drainage technique appears to be safer and more beneficial than conventional closed thoracic drainage procedures for treating pneumothorax. This technique offers advantages such as minimal scarring, lower VAS scores, and shorter insertion time, thereby improving safety and surgical outcomes.

14.
Materials (Basel) ; 17(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612111

RESUMO

Upcycling Cr-containing sulfate waste into catalysts for CO2 hydrogenation reaction benefits both pollution mitigation and economic sustainability. In this study, FeCrO3/Fe2O3 catalysts were successfully prepared by a simple hydrothermal method using Cr-containing sodium sulfate (Cr-SS) as a Cr source for efficient conversion and stable treatment of Cr. The removal rate of Cr in Cr-SS can reach 99.9% at the optimized hydrothermal conditions. When the synthesized catalysts were activated and used for the CO2 hydrogenation reaction, a 50% increase in CO2 conversion was achieved compared with the catalyst prepared by impregnation with a comparable amount of Cr. According to the extraction and risk assessment code (RAC) of the Reference Office of the European Community Bureau (BCR), the synthesized FeCrO3/Fe2O3 is risk-free. This work not only realizes the detoxification of the Cr-SS but transfers Cr into stable FeCrO3 for application in a catalytic field, which provides a strategy for the harmless disposal and resource utilization of Cr-containing hazardous waste.

15.
Soft Robot ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598719

RESUMO

Soft pneumatic actuators (SPAs) play a crucial role in generating movements and forces in soft robotic systems. However, existing SPA designs require significant structural modifications to be used in applications other than their original design. The present article proposes an omni-purpose fully 3D-printable SPA design inspired by membrane type mold and cast SPAs. The design features a spring-like zig-zag structure 3D-printed using an affordable 3D printer with thermoplastic polyurethane and a minimum wall thickness between 0.4 and 0.6 mm. The new SPA can perform unidirectional extension (30% extension) and bidirectional (rotation around same axis) bending (100°), with the ability to exert 10 N blocking force for 350 kPa pressure input. In addition, the design exhibits the capability to be scaled down for the purpose of accommodating limited spaces, while simultaneously enabling the reconfigurable interconnection of multiple SPAs to adapt to larger areas and navigate intricate trajectories that were not originally intended. The SPA's ability to be used in multiple applications without structural modification was validated through testing as a robot end-effector (gripper), artificial muscles in a soft tendon-driven prosthetic hand, a tube/tunnel navigator, and a robot crawler.

16.
Mamm Genome ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600211

RESUMO

Varicella-zoster virus (VZV), a common pathogen with humans as the sole host, causes primary infection and undergoes a latent period in sensory ganglia. The recurrence of VZV is often accompanied by severe neuralgia in skin tissue, which has a serious impact on the life of patients. During the acute infection of VZV, there are few related studies on the pathophysiological mechanism of skin tissue. In this study, transcriptome sequencing data from the acute response period within 2 days of VZV antigen stimulation of the skin were used to explore a model of the trajectory of skin tissue changes during VZV infection. It was found that early VZV antigen stimulation caused activation of mainly natural immune-related signaling pathways, while in the late phase activation of mainly active immune-related signaling pathways. JAK-STAT, NFκB, and TNFα signaling pathways are gradually activated with the progression of infection, while Hypoxia is progressively inhibited. In addition, we found that dendritic cell-mediated immune responses play a dominant role in the lesion damage caused by VZV antigen stimulation of the skin. This study provides a theoretical basis for the study of the molecular mechanisms of skin lesions during acute VZV infection.

17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(2): 249-255, 2024 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-38645848

RESUMO

Intervertebral disc degeneration is widely recognized as one of the main causes of lower back pain. Intervertebral disc cells are the primary cellular components of the discs, responsible for synthesizing and secreting collagen and proteoglycans to maintain the structural and functional stability of the discs. Additionally, intervertebral disc cells are involved in maintaining the nutritional and metabolic balance, as well as exerting antioxidant and anti-inflammatory effects within the intervertebral discs. Consequently, intervertebral disc cells play a crucial role in the process of disc degeneration. When these cells are exposed to oxidative stress, mitochondria can be damaged, which may disrupt normal cellular function and accelerate degenerative changes. Mitochondria serve as the powerhouse of cells, being the primary energy-producing organelles that control a number of vital processes, such as cell death. On the other hand, mitochondrial dysfunction may be associated with various degenerative pathophysiological conditions. Moreover, mitochondria are the key site for oxidation-reduction reactions. Excessive oxidative stress and reactive oxygen species can negatively impact on mitochondrial function, potentially leading to mitochondrial damage and impaired functionality. These factors, in turn, triggers inflammatory responses, mitochondrial DNA damage, and cell apoptosis, playing a significant role in the pathological processes of intervertebral disc cell degeneration. This review is focused on exploring the impact of oxidative stress and reactive oxygen species on mitochondria and the crucial roles played by oxidative stress and reactive oxygen species in the pathological processes of intervertebral disc cells. In addition, we discussed current cutting-edge treatments and introduced the use of mitochondrial antioxidants and protectants as a potential method to slow down oxidative stress in the treatment of disc degeneration.

19.
Water Res ; 256: 121567, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38581983

RESUMO

Discovery of nitrate/nitrite-dependent anaerobic methane oxidation (DAMO) challenges the conventional biological treatment processes, since it provides a possibility of simultaneously mitigating dissolved methane emissions from anaerobic effluents and reducing additional carbon sources for denitrification. Due to the slow growth of specialized DAMO microbes, this possibility has been just practiced with biofilms in membrane biofilm reactors or granular sludge in membrane bioreactors. In this study, simultaneous elimination of dissolved methane from anaerobic effluents and nitrate/nitrite reduction was achieved in a conventional anoxic reactor with magnetite. Calculations of electron flow balance showed that, with magnetite the eliminated dissolved methane was almost entirely used for nitrate/nitrite reduction, while without magnetite approximately 52 % of eliminated dissolved methane was converted to unknown organics. Metagenomic sequencing showed that, when dissolved methane served as an electron donor, the abundance of genes for reverse methanogenesis and denitrification dramatically increased, indicating that anaerobic oxidation of methane (AOM) coupled to nitrate/nitrite reduction occurred. Magnetite increased the abundance of genes encoding the key enzymes involved in whole reverse methanogenesis and Nir and Nor involved in denitrification, compared to that without magnetite. Analysis of microbial communities showed that, AOM coupled to nitrate/nitrite reduction was proceeded by syntrophic consortia comprised of methane oxidizers, Methanolinea and Methanobacterium, and nitrate/nitrite reducers, Armatimonadetes_gp5 and Thauera. With magnetite syntrophic consortia exchanged electrons more effectively than that without magnetite, further supporting the microbial growth.

20.
Br J Cancer ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582810

RESUMO

BACKGROUND: Mitochondrial dynamics play a fundamental role in determining stem cell fate. However, the underlying mechanisms of mitochondrial dynamics in the stemness acquisition of cancer cells are incompletely understood. METHODS: Metabolomic profiling of cells were analyzed by MS/MS. The genomic distribution of H3K27me3 was measured by CUT&Tag. Oral squamous cell carcinoma (OSCC) cells depended on glucose or glutamine fueling TCA cycle were monitored by 13C-isotope tracing. Organoids and tumors from patients and mice were treated with DRP1 inhibitors mdivi-1, ferroptosis inducer erastin, or combination with mdivi-1 and erastin to evaluate treatment effects. RESULTS: Mitochondria of OSCC stem cells own fragment mitochondrial network and DRP1 is required for maintenance of their globular morphology. Imbalanced mitochondrial dynamics induced by DRP1 knockdown suppressed stemness of OSCC cells. Elongated mitochondria increased α-ketoglutarate levels and enhanced glutaminolysis to fuel the TCA cycle by increasing glutamine transporter ASCT2 expression. α-KG promoted the demethylation of histone H3K27me3, resulting in downregulation of SNAI2 associated with stemness and EMT. Significantly, suppressing DRP1 enhanced the anticancer effects of ferroptosis. CONCLUSION: Our study reveals a novel mechanism underlying mitochondrial dynamics mediated cancer stemness acquisition and highlights the therapeutic potential of mitochondria elongation to increase the susceptibility of cancer cells to ferroptosis.

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