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1.
Chem Biol Interact ; 395: 110999, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608999

RESUMO

Bruceantinol (BOL), isolated from the dried fruit of the Brucea javanica (L.) Merr., exhibits cytotoxic effects on breast cancer cells. However, the underlying mechanism remains to be fully addressed. In this paper, the MCF-7 and MDA-MB-231 human breast cancer cell lines were used as experimental models to uncover how BOL inhibits breast cancer cell growth. The effects of BOL on cell growth, proliferation, the cell cycle, and apoptosis were investigated using the MTT assays, EdU incorporation assays, and flow cytometry, respectively. Bioinformatics techniques were applied to predict the key targets of BOL in breast cancer. Subsequent validation of these targets and the anti-breast cancer mechanism of BOL was conducted through Western blotting, RT-PCR, siRNA transfection, and molecular docking analysis. The results demonstrated that BOL dose- and time-dependently reduced the growth of both cell lines, impeded cell proliferation, disrupted the cell cycle, and induced necrosis in MCF-7 cells and apoptosis in MDA-MB-231 cells. Furthermore, CDK2/4/6 were identified as BOL targets, and their knockdown reduced cell sensitivity to BOL. BOL was found to potentially bind with CDK2/4/6 to facilitate protein degradation through the proteasome pathway. Additionally, BOL activated ERK in MDA-MB-231 cells, and this activation was required for BOL's functions in these cells. Collectively, BOL may act as an inhibitor of CDK2/4/6 to exert anti-breast cancer effects. Its effects on cell growth and CDK2/4/6 expression may also depend on ERK activation in HRs-HER2- breast cancer cells. These results suggest the potential of using BOL for treating breast cancer.

2.
Front Microbiol ; 15: 1286822, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655080

RESUMO

Winged helix (wH) domains, also termed winged helix-turn-helix (wHTH) domains, are widespread in all kingdoms of life and have diverse roles. In the context of DNA binding and DNA modification sensing, some eukaryotic wH domains are known as sensors of non-methylated CpG. In contrast, the prokaryotic wH domains in DpnI and HhiV4I act as sensors of adenine methylation in the 6mApT (N6-methyladenine, 6mA, or N6mA) context. DNA-binding modes and interactions with the probed dinucleotide are vastly different in the two cases. Here, we show that the role of the wH domain as a sensor of adenine methylation is widespread in prokaryotes. We present previously uncharacterized examples of PD-(D/E)XK-wH (FcyTI, Psp4BI), PUA-wH-HNH (HtuIII), wH-GIY-YIG (Ahi29725I, Apa233I), and PLD-wH (Aba4572I, CbaI) fusion endonucleases that sense adenine methylation in the Dam+ Gm6ATC sequence contexts. Representatives of the wH domain endonuclease fusion families with the exception of the PLD-wH family could be purified, and an in vitro preference for adenine methylation in the Dam context could be demonstrated. Like most other modification-dependent restriction endonucleases (MDREs, also called type IV restriction systems), the new fusion endonucleases except those in the PD-(D/E)XK-wH family cleave close to but outside the recognition sequence. Taken together, our data illustrate the widespread combinatorial use of prokaryotic wH domains as adenine methylation readers. Other potential 6mA sensors in modified DNA are also discussed.

3.
Front Nutr ; 11: 1368459, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650638

RESUMO

Objective: Given the high prevalence of non-alcoholic fatty liver disease (NAFLD) and its potential to progress to liver fibrosis, it is crucial to identify the presence of NAFLD in patients to guide their subsequent management. However, the current availability of non-invasive biomarkers for NAFLD remains limited. Therefore, further investigation is needed to identify and develop non-invasive biomarkers for NAFLD. Methods: A retrospective analysis was conducted on 11,883 patients admitted to the Healthcare Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, from January 2016 to December 2019 and divided into NAFLD and non-NAFLD groups. Anthropometric and laboratory examination data were collected. The correlations between variables and NAFLD were evaluated using the student's t-test or Mann-Whitney U test and binary logistic regression analysis. The predictive ability of these variables for NAFLD was assessed using the areas under the curves (AUCs) of receiver operating characteristics. Results: Among the included patients, 3,872 (32.58%) were diagnosed with NAFLD, with 386 (9.97%) individuals having liver fibrosis. Patients with NAFLD exhibited a higher proportion of males, elevated body mass index (BMI), and increased likelihood of hypertension, diabetes mellitus, and atherosclerosis. Logistic regression analysis identified the neutrophil to albumin ratio (NAR) as the most promising novel inflammation biomarkers, with the highest AUC value of 0.701, a cut-off value of 0.797, sensitivity of 69.40%, and specificity of 66.00% in identifying the risk of NAFLD. Moreover, NAR demonstrated superior predictive value in identifying NAFLD patients at risk of liver fibrosis, with an AUC value of 0.795, sensitivity of 71.30%, and specificity of 73.60% when NAR reached 1.285. Conclusion: These findings highlight that the novel inflammatory biomarker, NAR, is a convenient and easily accessible non-invasive predictor for NAFLD and NAFLD with liver fibrosis.

4.
J Hazard Mater ; 471: 134333, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38643581

RESUMO

Microplastics (MPs) are emerging contaminants found globally. However, their effects on soil-plant systems in salt-affected habitats remain unknown. Here, we examined the effects of polyethylene (PE) and polylactic acid (PLA) on soil properties, maize performance, and bacterial communities in soils with different salinity levels. Overall, MPs decreased soil electrical conductivity and increased NH4+-N and NO3--N contents. Adding NaCl alone had promoting and inhibitive effects on plant growth in a concentration-dependent manner. Overall, the addition of 0.2% PLA increased shoot biomass, while 2% PLA decreased it. Salinity increased Na content and decreased K/Na ratio in plant tissues (particularly roots), which were further modified by MPs. NaCl and MPs singly and jointly regulated the expression of functional genes related to salt tolerance in leaves, including ZMSOS1, ZMHKT1, and ZMHAK1. Exposure to NaCl alone had a slight effect on soil bacterial α-diversity, but in most cases, MPs increased ACE, Chao1, and Shannon indexes. Both MPs and NaCl altered bacterial community composition, although the specific effects varied depending on the type and concentration of MPs and the salinity level. Overall, PLA had more pronounced effects on soil-plant systems compared to PE. These findings bridge knowledge gaps in the risks of MPs in salt-affected habitats.

5.
Opt Express ; 32(6): 9397-9404, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571175

RESUMO

This research proposed a novel pulse-shaping design for directly shaping distorted pulses after the amplification. Based on the principle of the design we made a pulse shaper. With this pulse shaper, we successfully manipulate the pulse's leading edge and width to achieve an 'M'-shaped waveform in an amplification system. Comparative experiments were conducted within this system to compare the output with and without the integration of the pulse shaper. The results show a significant suppression of the nonlinear effect upon adding the pulse shaper. This flexible and effective pulse shaper can be easily integrated into a high-power all-fiber system, supplying the capability to realize the desired output waveform and enhance the spectral quality.

6.
J Phys Chem Lett ; : 4640-4646, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647347

RESUMO

Photocatalytic conversions of ethanol to valuable chemicals are significant organic synthesis reactions. Herein, we developed a CuCl2/FeCl3 bimetallic photocatalyst for sustainable dehydration of ethanol to ethylene by recoverable redox cycles. The selectivity of ethylene was 98.3% for CuCl2/FeCl3, which is much higher than that of CuCl2 (34.5%) and FeCl3 (86.5%). Due to the ligand-to-metal charge transfer (LMCT) process involved in generating the liquid products, the CuCl2/FeCl3 catalyst will be reduced to CuCl/FeCl2. Oxygen (O2) is required for the recovery of CuCl2/FeCl3 to avoid exhaustion. The soluble Fe3+/Fe2+ redox species deliver catalyst regeneration properties more efficiently than single metal couples, making a series of redox reactions (Cu2+/Cu+, Fe3+/Fe2+, and O2/ethanol couples) recyclable with synergistic effects. A flow reactor was designed to facilitate the continuous production of ethylene. The understanding of bimetallic synergism and consecutive reactions promotes the industrial application process of photocatalytic organic reactions.

7.
J Ethnopharmacol ; 328: 118024, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38484952

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Polygonatum sibiricum, commonly known as Siberian Solomon's seal, is a traditional herb widely used in various traditional medical systems, especially in East Asia. In ancient China, the use of polygonatum sibiricum in medicine and food was mentioned in Li Shizhen's Bencao Gangmu of traditional Chinese medicine (TCM). It was also used in history of India in Vedic medicine. The plant is rich in bioactive substances such as polysaccharides, saponins, flavonoid and alkaloids. AIM OF THE REVIEW: The aim of this review is to understand the pharmacological and pharmacokinetics research progress of the major components of polygonatum sibiricum, and to prospect its potential application and development in the treatment of various diseases. MATERIALS AND METHODS: We conducted a systematic literature search against major online databases on the Web, including PubMed, ancient books, patents, PubMed, Wiley, Google Scholar, Web of Science, and others. We select the pharmacological process and mechanism of the main components of polygonatum sibiricum in a variety of diseases, and make a strict but careful supplement and in-depth elaboration to this review. RESULTS: Several studies have demonstrated the strong antioxidant properties of polygonatum extract, which can be attributed to the presence of flavonoids and other polyphenol compounds; for diabetes and other metabolic-related diseases, polygonatum saponins have particular advantages in regulating intestinal flora and lipoprotein concentration in organisms. In addition, the polysaccharides extracted from this plant have a strong anti-inflammatory effect, which is related to its ability to regulate proinflammatory cytokine and mediators. In the aspect of anti-tumor effect, polygonatum derivatives can induce cancer cell apoptosis mainly by adjusting the cell membrane potential and cell cycle. It is worth noting that the combined action of the main components of polygonatum also offers promising solutions for the treatment of the disease. CONCLUSION: Polygonatum polysaccharide has therapeutic effects on many diseases by adjusting cell signal pathways, polygonatum sibiricum have significant advantages in regulating intestinal flora, inducing apoptosis of tumor cells, activating antioxidant processes, etc. Further research and basic exploration are needed to prove the function and mechanisms of the main components of polygonatum sibiricum on related diseases. The study on the immunomodulatory properties of polygonatum revealed its potentiality of enhancing immune function, which made it an interesting subject for further exploration in the field of immunotherapy.


Assuntos
Polygonatum , Saponinas , Polygonatum/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Medicina Tradicional Chinesa , Polissacarídeos/farmacologia , Saponinas/farmacologia
8.
Antimicrob Agents Chemother ; 68(4): e0101523, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38470112

RESUMO

Existing pharmacodynamic (PD) mathematical models for drug combinations discriminate antagonistic, additive, multiplicative, and synergistic effects, but fail to consider how concentration-dependent drug interaction effects may vary across an entire dose-response matrix. We developed a two-way pharmacodynamic (TWPD) model to capture the PD of two-drug combinations. TWPD captures interactions between upstream and downstream drugs that act on different stages of viral replication, by quantifying upstream drug efficacy and concentration-dependent effects on downstream drug pharmacodynamic parameters. We applied TWPD to previously published in vitro drug matrixes for repurposed potential anti-Ebola and anti-SARS-CoV-2 drug pairs. Depending on the drug pairing, the model recapitulated combined efficacies as or more accurately than existing models and can be used to infer efficacy at untested drug concentrations. TWPD fits the data slightly better in one direction for all drug pairs, meaning that we can tentatively infer the upstream drug. Based on its high accuracy, TWPD could be used in concert with PK models to estimate the therapeutic effects of drug pairs in vivo.


Assuntos
COVID-19 , Doença pelo Vírus Ebola , Humanos , Modelos Biológicos , SARS-CoV-2 , Doença pelo Vírus Ebola/tratamento farmacológico , Combinação de Medicamentos
9.
Eur J Pharmacol ; : 176538, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38552940

RESUMO

Chemotherapy is one of the primary and indispensable intervention against cancers though it is always accompanied by severe side effects especially cachexia. Cachexia is a fatal metabolic disorder syndrome, mainly characterized by muscle loss. Oxidative stress is the key factor that trigger cachectic muscle loss by inducing imbalance in protein metabolism and apoptosis. Here, we showed an oral compound (Z526) exhibited potent alleviating effects on C2C12 myotube atrophy induced by various chemotherapeutic agents in vitro as well as mice muscle loss and impaired grip force induced by oxaliplatin in vivo. Furthermore, Z526 also could ameliorate C2C12 myotube atrophy induced by the combination of chemotherapeutic agents with conditioned medium of various tumor cells in vitro as well as mice muscle atrophy of C26 tumor-bearing mice treated with oxaliplatin. The pharmacological effects of Z526 were based on its potency in reducing oxidative stress in cachectic myocytes and muscle tissues, which inhibited the activation of NF-κB and STAT3 to decrease Atrogin-1-mediated protein degradation, activated the AKT/mTOR signaling pathway to promote protein synthesis, regulated Bcl-2/BAX ratio to reduce Caspase-3-triggered apoptosis. Our work suggested Z526 to be an optional strategy for ameliorating cachexia muscle atrophy in the multimodality treatment of cancers.

10.
Sci Rep ; 14(1): 7504, 2024 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553622

RESUMO

Diffuse myocardial fibrosis is associated with adverse outcomes in heart failure with preserved ejection fraction (HFpEF). Dual-energy CT (DECT) can noninvasively assess myocardial fibrosis by quantification of extracellular volume (ECV) fraction. This study evaluated the association between ECV measured by DECT and clinical outcomes in patients with HFpEF. 125 hospitalized HFpEF patients were enrolled in this retrospective cohort study. ECV was measured using DECT with late iodine enhancement. The composite endpoint was defined as HFpEF hospitalization and all-cause mortality during the follow-up. During the median follow-up of 10.4 months, 34 patients (27.20%) experienced the composite outcomes, including 5 deaths; and 29 HFpEF hospitalizations. The higher DECT-ECV group had higher rates of composite outcomes than the low ECV group (log-rank X2 = 6.818, P = 0.033). In multivariate Cox regression analysis, the ECV (HR 1.17, 95% CI 1.06-1.30, P = 0.001) and NT-pro BNP (HR 2.83, 95% CI 1.16-6.88, P = 0.022) were independent risk factors for the adverse outcomes. Myocardial ECV measured using DECT was an independent risk factor for adverse outcomes in patients with HFpEF.


Assuntos
Cardiomiopatias , Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/diagnóstico por imagem , Prognóstico , Volume Sistólico , Estudos Retrospectivos , Imagem Cinética por Ressonância Magnética , Fibrose , Tomografia Computadorizada por Raios X , Função Ventricular Esquerda , Valor Preditivo dos Testes
11.
Eur Respir J ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514093

RESUMO

RATIONALE: Respiratory virus-induced inflammation is the leading cause of asthma exacerbation, frequently accompanied by induction of IFN-stimulated genes (ISGs). How asthma genetic susceptible genes modulate cellular response upon viral infection through fine-tuning ISGs induction and subsequent airway inflammation in genetically susceptible asthmatics remains largely unknown. OBJECTIVES: To decipher the functions of GSDMB in respiratory virus-induced lung inflammation. METHODS: In two independent cohorts, we analyzed expression correlation between GSDMB and ISGs. In human bronchial epithelial cell line or primary cells, we generated GSDMB-overexpressing and -deficient cells. A series of qPCR, ELISA and co-immunoprecipitation assays were performed to determine the function and mechanism of GSDMB for ISGs induction. We also generated a novel transgenic mouse line with inducible expression of human unique GSDMB gene in airway epithelial cells and applied respiratory syncytial virus (RSV) infection to determine the role of GSDMB on RSV-induced lung inflammation in vivo. MEASUREMENTS AND MAIN RESULTS: Gasdermin B encoded by GSDMB, one of the most significant asthma-susceptible genes at 17q21, acts as a novel RNA sensor, promoting MAVS-TBK1 signaling and subsequent inflammation. In airway epithelium, GSDMB is induced by respiratory viral infections. Expression of GSDMB and ISGs significantly correlated in respiratory epithelium from two independent asthma cohorts. Notably, inducible expression of human GSDMB gene in mouse airway epithelium leads to enhanced ISGs induction, increased airway inflammation with mucus hyper-secretion upon RSV infection. CONCLUSIONS: GSDMB promotes ISGs expression and airway inflammation upon respiratory virus infection, thereby conferring asthma risk in risk allele carriers.

12.
Phys Med Biol ; 69(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38471174

RESUMO

Cone beam computed tomography (CBCT) is known to suffer from strong scatter and cone beam artifacts. The purpose of this study is to develop and characterize a rapidly scanning carbon nanotube (CNT) field emission x-ray source array to enable a multisource CBCT (ms-CBCT) image acquisition scheme which has been demonstrated to overcome these limitations. A CNT x-ray source array with eight evenly spaced focal spots was designed and fabricated for a medium field of view ms-CBCT for maxillofacial imaging. An external multisource collimator was used to confine the radiation from each focal spot to a narrow cone angle. For ms-CBCT imaging, the array was placed in the axial direction and rapidly scanned while rotating continuously around the object with a flat panel detector. The x-ray beam profile, temporal and spatial resolutions, energy and dose rate were characterized and evaluated for maxillofacial imaging. The CNT x-ray source array achieved a consistent focal spot size of 1.10 ± 0.04 mm × 0.84 ± 0.03 mm and individual beam cone angle of 2.4°±0.08 after collimation. The x-ray beams were rapidly switched with a rising and damping times of 0.21 ms and 0.19 ms, respectively. Under the designed operating condition of 110 kVp and 15 mA, a dose rate of 8245µGy s-1was obtained at the detector surface with the inherent Al filtration and 2312µGy s-1with an additional 0.3 mm Cu filter. There was negligible change of the x-ray dose rate over many operating cycles. A ms-CBCT scan of an adult head phantom was completed in 14.4 s total exposure time for the imaging dose in the range of that of a clinical CBCT scanner. A spatially distributed CNT x-ray source array was designed and fabricated. It has enabled a new multisource CBCT to overcome some of the main inherent limitations of the conventional CBCT.


Assuntos
Nanotubos de Carbono , Raios X , Tomografia Computadorizada de Feixe Cônico/métodos , Tomografia Computadorizada por Raios X/métodos , Imagens de Fantasmas
13.
Pain Physician ; 27(3): E327-E336, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38506685

RESUMO

BACKGROUND: Kummell's disease (KD) and osteoporotic vertebral compression fracture (OVCF) are commonly found in patients with osteoporosis. Several studies have been conducted on bone cement distribution in OVCF or KD; a comparison between the 2 diseases is rarely reported. OBJECTIVES: To compare the clinical efficacy and bone cement distribution difference between KD and OVCFs after percutaneous kyphoplasty (PKP). STUDY DESIGN: This was a retrospective, nonrandomized controlled study. SETTING: Department of Orthopedics from an affiliated hospital. METHODS: From January 2018 to December 2020, 61 patients who underwent PKP surgery for single KD or OVCF and met the inclusion criteria were retrospectively reviewed. All patients were assigned to 2 groups: the KD group and the OVCF group. Clinical and radiologic characteristics, including the bone cement volume, leakage, bone cement dispersion scale, anterior vertebral height (AVH), median vertebral height (MVH), posterior vertebral height (PVH), Cobb angle and Visual Analog Scale (VAS) were analyzed and compared using Mimics three-dimensional (3D) reconstruction images and 3D reconstruction computed tomography, preoperatively, postoperatively, and 2 years after the operation, respectively. The correlations between the bone cement dispersion scale and the VH improvement rate (VHIR), VH change rate (VHCR), VAS improvement rate (VASIR), and follow-up VAS improvement rate (f-VASIR) were also evaluated. RESULTS: The mean follow-up time was 24.0 months. Postoperative VH, Cobb angle, vertebra volume, and VAS score were significantly improved in the 2 groups (P < 0.05). There was no statistical difference in postoperative parameters between the 2 groups. While a strong positive correlation between VHIR and bone cement dispersion scale was observed in the OVCF group (P < 0.01), no significant correlation between VHIR and bone cement dispersion scale was found in the KD group. There was no correlation between VASIR and bone cement dispersion scale in both groups. Compared with postoperation, VH was lower in both groups in later follow-up, and the difference between the 2 groups was statistically significant (P < 0.05). VH, VAS, f-VASIR, and VHCR had a worse manifestation in the KD group than in the OVCF group. However, no significant correlation was found between VHCR, f-VASIR, and bone cement dispersion scale in the 2 groups. LIMITATIONS: This study was limited by the non-randomized design, small sample size, and lack of a comprehensive follow-up period. CONCLUSIONS: Although there was no significant difference in the bone cement distribution and early clinical efficacy between KD and OVCF patients under the same surgical plan and surgeon, OVCF patients exhibited better long-term radiologic and clinical outcomes.


Assuntos
Fraturas por Compressão , Cifoplastia , Fraturas da Coluna Vertebral , Espondilose , Humanos , Cimentos Ósseos/uso terapêutico , Fraturas por Compressão/cirurgia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/cirurgia
14.
Heliyon ; 10(6): e27802, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38496869

RESUMO

rs2736098 is a synonymous polymorphism in TERT (telomerase reverse transcriptase), an enzyme involved in tumor onset of multiple tissues, and should play no roles in carcinogenesis. However, a search in cancer somatic mutation database indicated that the mutation frequency at rs2736098 is much higher than the average one for TERT. Moreover, there are significant H3K4me1 and H3K27Ac signals, two universal histone modifications for active enhancers, surrounding rs2736098. Therefore, we hypothesized that rs2736098 might be within an enhancer region, regulate TERT expression and influence cancer risk. Through luciferase assay, it was verified that the enhancer activity of rs2736098C allele is significantly higher than that of T in multiple tissues. Transfection of plasmids containing TERT coding region with two different alleles indicated that rs2736098C allele can induce a significantly higher TERT expression than T. By chromatin immunoprecipitation, it was observed that the fragment spanning rs2736098 can interact with USF1 (upstream transcription factor 1). The two alleles of rs2736098 present evidently different binding affinity with nuclear proteins. Database and literature search indicated that rs2736098 is significantly associated with carcinogenesis in multiple tissues and count of multiple cell types. All these facts indicated that rs2736098 is also an oncogenic polymorphism and plays important role in cell proliferation.

15.
ACS Omega ; 9(10): 11589-11596, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38496948

RESUMO

Tight sandstone reservoirs have become important areas for unconventional reservoir development, and their pore network is a key feature for identifying tight sandstone, which affects fluid migration path and reservoir development efficiency. However, the connectivity characteristics of the pore network at different scales have remained unclear owing to the numerous pores and uneven pore shape. Here, using pore size distributions from many hundreds of tight sandstone samples and subsequent topological data analysis, we construct the topological structure of the pore network in the Yanchang Formation tight sandstone of the Ordos Basin in China and visualize the topological characteristics of the pore network with distances. We show that there are three connected groups within the pore structure of the tight sandstone. The topology of the pore network resides on a trident ring manifold, suggesting that the pore network in the tight sandstone encompasses three obvious dominant connection paths. One prominent bar on the H0 dimension in the barcode indicates a two-point connection from nanoscale to microscale in the pore network. Three prominent bars with varying durations on the H1 dimension indicate the presence of three separate multipoint connections within a limited extent in the pore network. Connectivity of combined pores is good and controlled by the topological structure of the pore network. This demonstration of pore connections on a trident ring manifold provides a population-level visualization of the pore network in the tight sandstone.

16.
Bioresour Technol ; 398: 130529, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437969

RESUMO

The process of biological fermentation is often accompanied by the release of CO2, resulting in low yield and environmental pollution. Refixing CO2 to the product synthesis pathway is an attractive approach to improve the product yield. Cadaverine is an important diamine used for the synthesis of bio-based polyurethane or polyamide. Here, aiming to increase its final production, a RuBisCO-based shunt consisting of the ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and phosphoribulate kinase (PRK) was expressed in cadaverine-producing E. coli. This shunt was calculated capable of increasing the maximum theoretical cadaverine yield based on flux model analysis. When a functional RuBisCO-based shunt was established and optimized in E. coli, the cadaverine production and yield of the final engineered strain reached the highest level, which were 84.1 g/L and 0.37 g/g Glucose, respectively. Thus, the design of in situ CO2 fixation provides a green and efficient industrial production process.


Assuntos
Escherichia coli , Ribulose-Bifosfato Carboxilase , Ribulose-Bifosfato Carboxilase/metabolismo , Cadaverina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Dióxido de Carbono/metabolismo , Fermentação
17.
Opt Express ; 32(2): 2124-2131, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297749

RESUMO

This paper provides a method to effectively suppress the severe ASE self-saturation when achieving high repetition frequency tunability with high output power and narrow pulse width in active Q-switched all-fiber lasers. By studying the regularity of the system's multi-stable state, we first ensured that the laser system operated in a steady state. Then output avoids uneven distribution of pulse energy or missing pulses due to period bifurcation state or chaos state. By adding multiple gain sub-rings within the cavity, the sub-ring structure itself indirectly mitigates the ASE self-saturation while smoothing the pulse. The method will avoid the severe power loss caused by traditional smoothing methods by adjusting the AOM rising edge time. It will also avoid lowering the ASE lasing threshold at high repetition frequency. Meanwhile, the intra-cavity backward ASE can be effectively absorbed by inserting the gain fiber in the sub-rings to directly mitigate the ASE self-saturation. The system's continuously adjustable repetition frequency can be as high as over 300 kHz. It ensures that output power above the watt level and a < 0.2 nm narrow bandwidth can be maintained while tuning the repetition frequency. The narrowest smoothing pulse width of 28 ns has been reached.

18.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338929

RESUMO

Moderate control of rice tillering and the development of rice varieties with large panicles are important topics for future high-yield rice breeding. Herein, we found that low-tillering rice varieties stopped tillering earlier and had a larger leaf area of the sixth leaf. Notably, at 28 days after sowing, the rice seedlings of the low-tillering group had an average single-culm above-ground biomass of 0.84 g, significantly higher than that of the multi-tillering group by 56.26%, and their NSC (non-structural carbohydrate) and starch contents in sheaths were increased by 43.34% and 97.75%, respectively. These results indicated that the low-tillering group of rice varieties had a stronger ability to store photosynthetic products in the form of starch in their sheaths, which was thus more beneficial for their large panicle development. The results of carbon and nitrogen metabolism analyses showed that the low-tillering group had a relatively strong carbon metabolism activity, which was more favorable for the accumulation of photosynthesis products and the following development of large panicles, while the multi-tillering group showed relatively strong nitrogen metabolism activity, which was more beneficial for the development and formation of new organs, such as tillers. Accordingly, in the low-tillering rice varieties, the up-regulated genes were enriched in the pathways mainly related to the synthesis of carbohydrates, while the down-regulated genes were mainly enriched in the nitrogen metabolism pathways. This study provides new insights into the mechanism of rice tillering regulation and promotes the development of new varieties with ideal plant types.


Assuntos
Oryza , Oryza/metabolismo , Melhoramento Vegetal , Perfilação da Expressão Gênica , Nitrogênio/metabolismo , Carbono/metabolismo , Amido/metabolismo , Transcriptoma
19.
J Affect Disord ; 352: 259-266, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38367708

RESUMO

BACKGROUND: Recent years have seen increasing attention to improving depressive symptoms through dietary intakes, yet the association between thiamine intake and depression remains unclear. The present study aimed to explore this association using data from an American cross-sectional study. METHODS: We explored the association of covariates, exposure, and outcome with logistic regression equations. Multivariable regression models were performed to further exclude confounding factors. To investigate nonlinear relationships, we employed restricted cubic splines. Recursive algorithms were utilized to identify inflection points. Additionally, we conducted stratified analyses by age and sex to uncover differences among subgroups. RESULTS: When all covariates were adjusted, the association between thiamine intake and depression was not statistically significant [0.93 (0.82, 1.07)]. In the linear trend test using Q1 as the reference, the ORs (95%CI) for Q2, Q3, and Q4 were 0.87 (0.73, 1.04), 0.83 (0.68, 1.00), and 0.92 (0.73, 1.16), which suggested that the association might be nonlinear. We then confirmed this nonlinear relationship with a restricted cubic spline, and the inflection point of 1.35 mg/day was calculated. Before the inflection point, the effect value of the relationship was 0.68 (0.53, 0.89). After the inflection point, no significant association was found [1.10 (0.92, 1.31)]. Stratified analyses revealed that this nonlinear relationship was consistent among women and individuals aged <60 years. DISCUSSION: In this cross-sectional study among American general adults, we found a nonlinear association between thiamine intake and depression and further observed differences by age and sex.


Assuntos
Depressão , Estado Nutricional , Adulto , Humanos , Feminino , Estudos Transversais , Depressão/epidemiologia , Algoritmos , Tiamina , Inquéritos Nutricionais
20.
Sci Rep ; 14(1): 3887, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366012

RESUMO

Multisource cone beam computed tomography CBCT (ms-CBCT) has been shown to overcome some of the inherent limitations of a conventional CBCT. The purpose of this study was to evaluate the accuracy of ms-CBCT for measuring the bone mineral density (BMD) of mandible and maxilla compared to the conventional CBCT. The values measured from a multi-detector CT (MDCT) were used as substitutes for the ground truth. An anthropomorphic adult skull and tissue equivalent head phantom and a homemade calibration phantom containing inserts with varying densities of calcium hydroxyapatite were imaged using the ms-CBCT, the ms-CBCT operating in the conventional single source CBCT mode, and two clinical CBCT scanners at similar imaging doses; and a clinical MDCT. The images of the anthropomorphic head phantom were reconstructed and registered, and the cortical and cancellous bones of the mandible and the maxilla were segmented. The measured CT Hounsfield Unit (HU) and Greyscale Value (GV) at multiple region-of-interests were converted to the BMD using scanner-specific calibration functions. The results from the various CBCT scanners were compared to that from the MDCT. Statistical analysis showed a significant improvement in the agreement between the ms-CBCT and MDCT compared to that between the CBCT and MDCT.


Assuntos
Densidade Óssea , Tomografia Computadorizada de Feixe Cônico Espiral , Cabeça , Crânio , Tomografia Computadorizada de Feixe Cônico/métodos , Imagens de Fantasmas
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