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1.
J Clin Neurosci ; 123: 123-129, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569383

RESUMO

OBJECTIVE: By analysing the difference in TNF-α levels in the peripheral blood of patients with medial temporal lobe epilepsy (mTLE) with or without hippocampal sclerosis and the correlation between TNF-α and N-acetylaspartate levels in the hippocampus, we explored the relationship between TNF-α and the degree of damage to hippocampal sclerosis neurons in medial temporal lobe epilepsy. METHODS: This is a prospective, population-based study. A total of 71 Patients with medial temporal lobe epilepsy diagnosed by clinical seizures, video-EEG, epileptic sequence MRI, and other imaging examinations were recruited from October 2020 to July 2022 in the Department of Neurology, Affiliated Hospital of Xuzhou Medical University. Twenty age-matched healthy subjects were selected as the control group. The patients were divided into two groups: the medial temporal epilepsy with hippocampal sclerosis group (positive group, mTLE-HS-P group) and the medial temporal epilepsy without hippocampal sclerosis group (negative group, mTLE-HS-N group). The levels of IL-1ß, IL-5, IL-6, IL-8, IL-17, IFN-γ and TNF-α in the peripheral blood of the patients in the three groups were detected by multimicrosphere flow immunofluorescence assay. The level of N-acetylaspartate (NAA) in the hippocampus was measured by 1H-MRS. The differences in cytokine levels among the three groups were analysed, and the correlation between cytokine and NAA levels was analysed. RESULTS: The level of TNF-α in the peripheral blood of the patients in the mTLE-HS-P group was significantly higher than that of the patients in the mTLE-HS-N and healthy control groups, and the level of TNF-α in the patients in the mTLE-HS-N group was significantly higher than that of the patients in the healthy control group. The NAA level in mTLE-HS-P group patients was significantly lower than that of mTLE-HS-N patients and healthy controls, but there was no significant difference between mTLE-HS-N patients and healthy controls (P > 0.05). Spearman correlation analysis showed that TNF-α level (rs = -0.437, P < 0.05) and the longest duration of a single seizure (rs = -0.398, P < 0.05) were negatively correlated with NAA level. Logistic regression analysis showed that there was no significant correlation between the longest duration of a single seizure and hippocampal sclerosis, but TNF-α level was closely related to hippocampal sclerosis in patients with mTLE (OR = 1.315, 95 % CI 1.084-1.595, P = 0.005). CONCLUSION: The level of TNF-α in the peripheral blood of patients with medial temporal lobe epilepsy with hippocampal sclerosis was higher, and it was correlated with NAA and hippocampal sclerosis. The high expression of TNF-α may be of important value in the evaluation of hippocampal sclerosis patients.


Assuntos
Ácido Aspártico/análogos & derivados , Biomarcadores , Epilepsia do Lobo Temporal , Hipocampo , Esclerose , Fator de Necrose Tumoral alfa , Humanos , Epilepsia do Lobo Temporal/sangue , Epilepsia do Lobo Temporal/patologia , Hipocampo/patologia , Masculino , Feminino , Adulto , Fator de Necrose Tumoral alfa/sangue , Pessoa de Meia-Idade , Estudos Prospectivos , Biomarcadores/sangue , Ácido Aspártico/sangue , Ácido Aspártico/metabolismo , Adulto Jovem , Imageamento por Ressonância Magnética , Esclerose Hipocampal
2.
Int Immunopharmacol ; 132: 112024, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38608475

RESUMO

Ulcerative colitis (UC) is a recurrent intestinal disease with an increasing incidence worldwide that seriously affects the life of patients. Turtle peptide (TP) is a bioactive peptide extracted from turtles that has anti-inflammatory, antioxidant and anti-aging properties. However, studies investigating the effect of TP on the progression of UC are lacking. The aim of this study was to investigate effects and underlying mechanisms of TP and its derivative peptide GPAGPIGPV (GP-9) in alleviating UC in mice. The results showed that 500 mg/kg TP treatment significantly ameliorated colitis symptoms and oxidative stress in UC mice. TP alleviated intestinal barrier damage in UC mice by promoting mucosal repair and increasing the expression of tight junction proteins (ZO1, occludin and claudin-1). TP also modulated the composition of the gut microbiota by increasing the abundance of the beneficial bacteria Anaerotignum, Prevotellaceae_UCG-001, Alistipes, and Lachno-spiraceae_NK4A136_group and decreasing the abundance of the harmful bacteria Prevotella_9 and Parasutterella. Furthermore, we characterized the peptide composition of TP and found that GP-9 ameliorated the symptoms of dextran sodium sulfate (DSS)-induced colitis in mice by inhibiting the TLR4/NF-κB signaling pathway. In conclusion, TP and its derivative peptides ameliorated DSS-induced ulcerative colitis by inhibiting the expression of inflammatory factors and modulating the composition of the intestinal microbiota; this study provides a theoretical basis for the application of TP and its derivative peptides for their anti-inflammatory activity.

3.
Int Wound J ; 21(4): e14870, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38629599

RESUMO

To analyse the risk factors affecting wound healing and infection after spinal meningioma resection surgery. The surgical incision healing of 137 patients who underwent spinal meningioma resection at our hospital from January 2021 to January 2024 was analysed. The data collected included physical examination findings, haematological and biochemical measurements, and various scales assessed upon admission and after surgery. These data were then analysed. The surgical wound healing, infection and postoperative complications were statistically analysed. Multiple logistic regression analysis method was used to conduct risk factor analysis on corresponding indicators; the odds ratio and p value of 95% confidence interval were calculated. Factors such as age and smoking history were significantly negatively correlated with wound healing after meningioma resection (odds ratio < 1.000, p < 0.05), while preoperative albumin and platelet count were significantly positively correlated with wound healing (odds ratio > 1.000, p < 0.05). Age, WHO Meningioma Grading, preoperative albumin and preoperative platelet were significantly negatively correlated with wound infection after meningioma resection (odds ratio < 1.000, p < 0.05). The history of virus infection and history of neurological disorders were significantly positively correlated with wound infection (odds ratio > 1.000, p < 0.05). The influence of each factor is different. Age, smoking history, WHO Meningioma Grading, preoperative albumin, preoperative platelets, history of virus infection and history of neurological disorders had the greatest influence on wound healing and infection after meningioma resection.


Assuntos
Neoplasias Meníngeas , Meningioma , Ferida Cirúrgica , Viroses , Infecção dos Ferimentos , Humanos , Meningioma/cirurgia , Estudos Retrospectivos , Fatores de Risco , Cicatrização , Neoplasias Meníngeas/cirurgia , Albuminas
4.
Korean J Radiol ; 25(2): 189-198, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38288898

RESUMO

OBJECTIVE: To investigate the prognostic utility of radiomics features extracted from 18F-fluorodeoxyglucose (FDG) PET/CT combined with clinical factors and metabolic parameters in predicting progression-free survival (PFS) and overall survival (OS) in individuals diagnosed with extranodal nasal-type NK/T cell lymphoma (ENKTCL). MATERIALS AND METHODS: A total of 126 adults with ENKTCL who underwent 18F-FDG PET/CT examination before treatment were retrospectively included and randomly divided into training (n = 88) and validation cohorts (n = 38) at a ratio of 7:3. Least absolute shrinkage and selection operation Cox regression analysis was used to select the best radiomics features and calculate each patient's radiomics scores (RadPFS and RadOS). Kaplan-Meier curve and Log-rank test were used to compare survival between patient groups risk-stratified by the radiomics scores. Various models to predict PFS and OS were constructed, including clinical, metabolic, clinical + metabolic, and clinical + metabolic + radiomics models. The discriminative ability of each model was evaluated using Harrell's C index. The performance of each model in predicting PFS and OS for 1-, 3-, and 5-years was evaluated using the time-dependent receiver operating characteristic (ROC) curve. RESULTS: Kaplan-Meier curve analysis demonstrated that the radiomics scores effectively identified high- and low-risk patients (all P < 0.05). Multivariable Cox analysis showed that the Ann Arbor stage, maximum standardized uptake value (SUVmax), and RadPFS were independent risk factors associated with PFS. Further, ß2-microglobulin, Eastern Cooperative Oncology Group performance status score, SUVmax, and RadOS were independent risk factors for OS. The clinical + metabolic + radiomics model exhibited the greatest discriminative ability for both PFS (Harrell's C-index: 0.805 in the validation cohort) and OS (Harrell's C-index: 0.833 in the validation cohort). The time-dependent ROC analysis indicated that the clinical + metabolic + radiomics model had the best predictive performance. CONCLUSION: The PET/CT-based clinical + metabolic + radiomics model can enhance prognostication among patients with ENKTCL and may be a non-invasive and efficient risk stratification tool for clinical practice.


Assuntos
Linfoma de Células T , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Humanos , Fluordesoxiglucose F18 , Prognóstico , Estudos Retrospectivos , 60570
5.
Int J Biol Macromol ; 260(Pt 1): 129484, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242416

RESUMO

L-Tryptophan hydroxylation catalyzed by tryptophan hydroxylase (TPH) presents a promising method for synthesizing 5-hydroxytryptophan (5-HTP), yet the limited activity of wild-type human TPH2 restricts its application. A high-activity mutant, MT10 (H318E/H323E), was developed through semi-rational active site saturation testing (CAST) of wild-type TPH2, exhibiting a 2.85-fold increase in kcat/Km over the wild type, thus enhancing catalytic efficiency. Two biotransformation systems were developed, including an in vitro one-pot system and a Whole-Cell Catalysis System (WCCS). In the WCCS, MT10 achieved a conversion rate of only 31.5 % within 32 h. In the one-pot reaction, MT10 converted 50 mM L-tryptophan to 44.5 mM 5-HTP within 8 h, achieving an 89 % conversion rate, outperforming the M1 (NΔ143/CΔ26) variant. Molecular dynamics simulations indicated enhanced interactions of MT10 with the substrate, suggesting improved binding affinity and system stability. This study offers an effective approach for the efficient production of 5-HTP.


Assuntos
5-Hidroxitriptofano , Triptofano Hidroxilase , Humanos , 5-Hidroxitriptofano/metabolismo , Triptofano Hidroxilase/genética , Triptofano Hidroxilase/química , Triptofano Hidroxilase/metabolismo , Triptofano/química , Domínio Catalítico , Hidroxilação
6.
Pain Physician ; 27(1): 35-41, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38285033

RESUMO

BACKGROUND: A more secure and efficacious therapy than has been developed so far is imperative for patients suffering from recurrent trigeminal neuralgia (TN). Despite numerous reports on the use of enhanced percutaneous balloon compression (PBC) techniques, such as altering compression duration and balloon pressure, none have yielded satisfactory outcomes. With these issues in mind, we have employed the PBC double-compression technique for the first time. This technique involves initially inflating a balloon to expand the adhesive tissue in Meckel's lumen, followed by emptying of the contrast medium and subsequent slight catheter adjustment for further compression. The total duration of compression remains unchanged and may even be shortened. OBJECTIVES: The objective of this study was to assess the clinical effectiveness of the PBC double-compression technique in patients with recurrent TN and to analyze the technique's efficacy, subsequent duration of patients' facial numbness, and other complications. STUDY DESIGN: Retrospective study. SETTING: A single-center study. METHODS: Retrospective analysis was conducted on clinical data from 125 patients with postoperative recurrent TN who underwent double compression of the PBC and 65 patients who underwent single compression of the PBC between August 2017 and April 2022. The Barrow Neurological Institute Pain Intensity (BNI-P) score was utilized to quantify the severity of pain, while the Barrow Neurological Institute Facial Numbness (BNI-N) score was employed to separately evaluate the extent of postoperative pain relief and facial numbness. RESULTS: The BNI-P and BNI-N scores before and after PBC treatment are presented herein. At T0, there was no significant difference in the BNI-P scores between the single-compression group and the double-compression group; however, at T1-T4, the BNI-P scores of the double-compression group were lower than those of the single-compression group (P < 0.05). There was no significant difference in BNI-P scores between the 2 groups at T5. At T1-T4, the BNI-N score of the double-compression group was significantly lower than that of the single-compression group (P < 0.05). However, there was no significant difference in BNI-N score between the double and single compression groups at T5. In the single-compression group, one patient (1.5%) experienced insignificant pain relief on postoperative day one, while 2 patients (3.1%) suffered from pain recurrence during the 1-4-year follow-up period. Similarly, in the double-compression group, one patient (0.8%) had inadequate pain relief on postoperative day one, and 3 patients (2.4%) experienced pain recurrence during the same follow-up period. The remaining patients did not require further surgical intervention but continued to rely on regular oral analgesia. In the single-compression group, masticatory muscle weakness was observed in 50 cases (76.9%), while in the double-compression group, it was observed in 92 cases (73.6%). Perioral herpes affected 4 patients (7.1%) and 6 patients (4.8%) in the single- and double-compression groups, respectively. Facial hematoma occurred in 7 cases (10.8%) and 13 cases (10.4%) of the single- and double-compression groups, respectively; each group included one patient suffered who from diplopia. Notably, none of the patients in this study reported any instances of corneal anesthesia, anesthesia pain, aseptic meningitis, cerebrospinal fluid leakage, subarachnoid hemorrhage, carotid-cavernous fistula, or mortality. LIMITATIONS: This was a single-center retrospective study with a small sample size and relatively short follow-up time. Therefore, further evaluation of the long-term efficacy of PBC for postoperative recurrent TN is needed from multiple centers with larger sample sizes and longer follow-up periods. CONCLUSIONS: The double PBC method boasts a high cure rate, a low recurrence rate, and minimal complications, rendering the option appropriate for patients with recurrent TN and thus deserving of clinical promotion.


Assuntos
Neuralgia do Trigêmeo , Humanos , Neuralgia do Trigêmeo/cirurgia , Estudos Retrospectivos , Hipestesia , Dor , Manejo da Dor
7.
Int J Biol Macromol ; 258(Pt 1): 128889, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38123039

RESUMO

Color-changing fibers have attracted much attention for their wide applications in camouflage, security warnings, and anti-counterfeiting. The inorganic color-changing material tungsten trioxide (WO3) has been widely investigated for its good stability, controllability, and ease of synthesis. In this study, photochromic alginate fibers (WO3@Ca-Alg) were prepared by incorporating UV-responsive hybrid tungsten trioxide nanoparticles in the fiber production process. The prepared photochromic alginate fibers changed from white to dark blue after 30 min of UV irradiation and returned to their original color after 64 h. It can be seen that WO3@Ca-Alg has the advantage of long color duration. The strength of this fiber reached 2.61 cN/dtex and the limiting oxygen index (LOI) was 40.9 %, which indicates that the fiber exhibited mechanical resistance and flame-retardant properties. After the cross-linking of WO3@Ca-Alg by sodium tetraborate, a new core-shell structure was generated, which was able to encapsulate tungsten trioxide in it, thus reducing the amount of tungsten trioxide loss, and its salt and washing resistance was greatly improved. This photochromic alginate fiber can be mass produced and spun into yarn.


Assuntos
Retardadores de Chama , Nanopartículas , Tungstênio , Alginatos , Óxidos
8.
Nutrients ; 15(22)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38004208

RESUMO

The incidence of ulcerative colitis (UC) is increasing annually. There are few treatments for UC patients, and some drugs have serious side effects. Sea cucumber peptide (SCP) has anti-inflammatory, antioxidant and other biological activities, and various sea cucumber species are in pharmaceutical development. However, relevant studies on the effects of SCP on UC progression are still lacking. In this study, a mouse model of acute colitis was induced by 3% dextran sulfate (DSS), and the effect of 500 mg/kg SCP on colitis was investigated. The results showed that SCP can alleviate DSS-induced colon damage and intestinal barrier damage. SCP significantly inhibited the expression of inflammatory factors and oxidative stress in UC mice. SCP reversed the intestinal microbiota dysregulation induced by DSS, inhibited the growth of Sutterella, Prevotella_9 and Escherichia-Shigella harmful bacteria, and increased the abundance of Lachnospiraceae_NK4A136_group. At the same time, SCP treatment significantly inhibited the LPS-induced polarization of M1 macrophages, which may be mediated by two monopeptides, IPGAPGVP and TGPIGPPGSP, via FPR2. In conclusion, SCP can protect against colitis by modulating the intestinal microbiota composition and the intestinal barrier and inhibiting the polarization of M1 macrophages.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Pepinos-do-Mar , Humanos , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colo , Modelos Animais de Doenças , Macrófagos , Peptídeos/farmacologia , Sulfato de Dextrana , Camundongos Endogâmicos C57BL
9.
J Am Chem Soc ; 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37920956

RESUMO

The trifluoromethyl (CF3) group is an essential moiety in medicinal chemistry due to its unique physicochemical properties. While trifluoroacetic acid (TFA) is an inexpensive and easily accessible reagent, its use as a source of CF3 is highly challenging due to its high oxidation potential. In this study, we present a novel electrophotochemical approach that enables the use of TFA as the CF3 source for the selective, catalyst- and oxidant-free trifluoromethylation of (hetero)arenes. Key to our approach is the selective oxidation of TFA over arenes, generating CF3 radicals through oxidative decarboxylation. This strategy enables the sustainable and environmentally-friendly synthesis of CF3-, CF2H- and perfluoroalkyl-containing (hetero)arenes with a broad range of substrates. Importantly, our results demonstrate significantly improved chemoselectivity by light irradiation, opening up new possibilities for the synthetic and medicinal applications of TFA as an ideal yet underutilized CF3 source.

10.
J Biol Methods ; 10: e99010005, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023772

RESUMO

Mycoplasmas, which are the smallest and simplest prokaryotes, lack a cell wall but possess the ability to undergo self-replication. Mycoplasma contamination is a common problem for laboratories engaging in cell culture. Due to their small size, Mycoplasmas can easily permeate filters designed to prevent bacterial and fungal contamination in cell culture. Although Mycoplasma contamination usually does not result in cell death, it can significantly affect cell proliferation, metabolism, and cause chromosomal aberrations. Therefore, it is crucial to detect and eliminate Mycoplasma contamination in cell culture. This step-by-step protocol presents a comprehensive approach to prevent Mycoplasma contamination in cell culture, as well as to detect and eradicate Mycoplasma to ensure accurate experimental and sequencing results.

11.
ACS Omega ; 8(45): 42907-42920, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024704

RESUMO

The biodegradable activity antibacterial materials have been widely applied on food preservation because they not only protect foods from pathogenic attacks but also relieve environmental pollution. Biodegradable melt-blown nonwovens (MB) have several advantages over the other materials in terms of a simpler and more environmentally friendly fabrication process, higher specific surface area, and lower cost. Herein, polylactic acid (PLA) MB is first modified by polydopamine (PDA) to activate the surface. Then, chitosan (CS) and cinnamon essential oil (CEO) are used to decorate the surface of the modified PLA MB via a simple one-pot method to prepare CEO/CS@PLA MB with different CEO contents. Compared with PLA MB, CEO/CS@PLA MB had a rougher surface and larger average fiber diameter, while the average pore diameter and air permeability reduced. The input of CEO led to a decrease in the tensile strength of CEO/CS@PLA MB and an obvious increase in the elongation at break. The combination of CS and CEO shows excellent synergistic antibacterial effect. The antibacterial efficiencies of CEO/CS@PLA MB against Escherichia coli and Staphylococcus aureus enhance with the increase of the CEO content. When the weight ratio of CS to CEO is 1:2, the antibacterial efficiencies of CEO2/CS@PLA MB against E. coli and S. aureus are 99.98 and 99.99%, respectively. When being applied to the preservation of fresh strawberry, CEO2/CS@PLA MB can effectively inhibit the microbial growth in strawberry and reduce decay, which extends the shelf time of strawberry.

12.
Front Immunol ; 14: 1240149, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869011

RESUMO

Background: Radiofrequency ablation (RFA) and chemotherapy are used to treat lung cancer or pulmonary metastases, but no direct comparison of overall survival (OS) has been published. The present study aimed to assess the OS of RFA and/or chemotherapy in patients with lung cancer or pulmonary metastases who were not candidates for surgical resection. Methods: To identify relevant studies, the following databases were electronically searched from their inception to 31 March 2023: PubMed, Embase, Web of Science, Cochrane Library, Scopus, Ovid, ScienceDirect, SinoMed, China National Knowledge Infrastructure Database, Chongqing VIP Chinese Science and Technology Periodical Database, Wanfang Database, LILACS, ClinicalTrials.gov, and Chictr.org. Manual retrieval was also conducted. We used published hazard ratios (HRs) if available or estimates from other survival data. Results: A total of 1,387 participants from 14 trials were included in the final analysis. Patients treated with RFA combined with chemotherapy significantly improved OS compared with those treated with chemotherapy alone [HR 0.50, 95% confidence interval (CI) 0.41-0.61; p < 0.00001], with an absolute difference at 12 months of 29.6% (95% CI 23.7-35.5), at 24 months of 19.2% (95% CI 10.1-28.2), and at 36 months of 22.9% (95% CI 12.0-33.7). No statistically significant difference was observed in the subgroups of case type, cancer type, chemotherapy drugs, and tumor size. The HR for OS with RFA plus chemotherapy vs. RFA alone was 0.53 (95% CI 0.41-0.70; p < 0.00001), corresponding to a 27.1% (95% CI 18.3-35.8), 31.0% (95% CI 19.9-41.9), and 24.9% (95% CI 15.0-34.7) absolute difference in survival at 12 months, 24 months, and 36 months, respectively. Subgroup analysis by geographic region and TNM stage showed that RFA combined with chemotherapy still significantly improved OS compared to RFA. The HR of RFA vs. chemotherapy was 0.98 (95% CI 0.60-1.60; p = 0.94), with an absolute difference at 12 months of 1.4% (95% CI -19.2 to 22.1), at 24 months of 7.8% (95% CI -11.3 to 26.8), and at 36 months of 0.3% (95% CI -13.2 to 13.8). The overall indirect comparison of OS for RFA vs. chemotherapy was 0.95 (95% CI 0.72-1.26; p = 0.74). Data on progression-free survival were not sufficiently reported. Conclusion: RFA combined with chemotherapy might be a better treatment option for patients with lung cancer or pulmonary metastases than chemotherapy alone or RFA alone. The comparison between RFA and/or chemotherapy remains to be specifically tested. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=335032, identifier CRD42022335032.


Assuntos
Ablação por Cateter , Neoplasias Pulmonares , Ablação por Radiofrequência , Humanos , Resultado do Tratamento , Neoplasias Pulmonares/etiologia , Modelos de Riscos Proporcionais
13.
RSC Adv ; 13(44): 30680-30689, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37869388

RESUMO

Electrospun nanofiber membranes have been extensively studied as air filters. However, their limited filtration efficiency for submicron inhalable particulate matter (PM), high resistance to filtration, and limited capacity to hold dust have hindered their widespread use. The majority of materials come from petroleum, and the use of organic solvents during the spinning process has a significant negative impact on the environment. In this work, a sustainable method has been proposed for producing filters using poly(lactic acid) (PLA) with a bimodal diameter distribution through conjugated electrospinning. This technique allows for the continuous production of interconnected micro/nano hybrid porous membranes, resulting in reduced resistance and improved dust holding capacity. The filtration efficiency, pressure drop, long-term filtration performance, and actual performance of the conjugated bimodal membrane (CBM) were extensively investigated. The results indicate that the filter has a high capacity for retaining particles, with filtration efficiencies of 99.94% for PM 0.3 and 99.96% for PM 2.5. It also demonstrates a high quality factor (0.078 Pa-1 for PM 0.3 and 0.084 Pa-1 for PM 2.5), long-term stability (a decrease of 2.35% for PM 0.3 and 0.05% for PM 2.5 over a period of 60 days) and outstanding dust holding capacity (9.17 g m-2). The conjugated bimodal membrane (CBM) shows a 22.64% decrease in resistance compared to the non-conjugated bimodal membrane (BM). In general, the approach outlined in this work provides valuable insights into the development of high-performance biodegradable air filters. These filters have improved filtration efficiency and reduced resistance.

14.
Opt Express ; 31(20): 32813-32823, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859075

RESUMO

Optical frequency combs with more than 10 W have paved the way for extreme ultraviolet combs generation by interaction with inert gases, leading to extreme nonlinear spectroscopy and the ultraviolet nuclear clock. Recently, the demand for an ultra-long-distance time and frequency space transfer via optical dual-comb proposes a new challenge for high power frequency comb in respect of power scaling and optical frequency stability. Here we present a frequency comb based on fiber chirped pulse amplification (CPA), which can offer more than 20 W output power. We further characterize the amplifier branch noise contribution by comparing two methods of locking to an optical reference and measure the out-of-loop frequency instability by heterodyning two identical high-power combs. Thanks to the low noise CPA, reasonable locking method, and optical path-controlled amplifiers, the out-of-loop beat note between two combs demonstrates the unprecedented frequency stability of 4.35 × 10-17 at 1s and 6.54 × 10-19 at 1000 s.

15.
Water Res ; 245: 120570, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37703754

RESUMO

The low terrain and the prosperous agriculture in the east of China, have caused the accumulation of pesticide residues in the estuaries. Therefore, this study analyzed the spatiotemporal distribution and partition tendency of 106 pesticides based on their abundance, frequencies, and concentrations in the aquatic environment of 16 river estuaries in 7 major basins in the eastern China by using solid-phase extraction (SPE) with high-performance liquid chromatography tandem mass spectrometry (HPLC‒MS/MS) and gas chromatography tandem mass spectrometry (GC‒MS/MS). In addition, potential risk of multiple pesticides was also evaluated. The results showed that herbicides were the dominant pesticide type, while triazines were the predominate substance group of pesticide. In addition, triadimenol, vinclozolin, diethylatrazine, prometryn, thiamethoxam, atrazine, and metalachlor were the major pesticides in the water, while prometryn, metalachlor, and atrazine were the main pesticides in the sediment. The average total concentration of pesticide was 751.15 ng/L in the dry season, 651.17 ng/L in the wet season, and 617.37 ng/L in the normal season, respectively. The estuaries of the Huai River Basin, the Yangtze River Basin, the Hai River Basin, and the Yellow River Basin have been affected by the low pollution treatment efficiency, weak infrastructure, and agricultural/non-agricultural activities in eastern China, resulting in relatively serious pesticide pollution. The estuaries of Huaihe River, Yangtze River, Xiaoqing River, and Luanhe River had large pesticide abundance and comparatively severe pesticide pollution, while the estuaries of Tuhai River and Haihe River had heavy pesticide contamination in the sediment, which might be induced by historical sedimentary factors. The log KOC values showed that except for thioketone, other pesticides were relatively stable due to the adsorption by sediment. The ecological risk assessment results indicated that insecticides had a high risk. Teenagers were the most severely affected by the noncarcinogenic risk of pesticides, while adults were mostly affected by the carcinogenic risk of pesticides. Therefore, pesticide hazards in the water environment of estuaries in eastern China needs to be further close supervision.

16.
Inorg Chem ; 62(33): 13293-13303, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37557894

RESUMO

The reprocessing of spent nuclear fuel is critical for the sustainability of the nuclear energy industry. However, several key separation processes present challenges in this regard, calling for continuous research into next-generation separation materials. Herein, we propose a high-throughput screening framework to improve efficiency in identifying potential ligands that selectively coordinate metal cations of interest in liquid wastes that considers multiple key chemical characteristics, including aqueous solubility, pKa, and coordination bond length. Machine-learning models were designed for the fast and accurate prediction of these characteristics by using graph convolution and transfer-learning techniques. Suitable ligands for Cs/Sr crystallizing separation were identified through the "computational funnel", and several top-ranking, nontoxic, low-cost ligands were selected for experimental verification.

17.
Int J Mol Sci ; 24(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37511626

RESUMO

L-tryptophan (L-trp), produced through bio-manufacturing, is widely used in the pharmaceutical and food industries. Based on the previously developed L-trp-producing strain, this study significantly improved the titer and yield of L-trp, through metabolic engineering of the shikimate pathway and the L-tryptophan branch. First, the rate-limiting steps in the shikimate pathway were investigated and deciphered, revealing that the combined overexpression of the genes aroE and aroD increased L-trp production. Then, L-trp synthesis was further enhanced at the shaking flask level by improving the intracellular availability of L-glutamine (L-gln) and L-serine (L-ser). In addition, the transport system and the competing pathway of L-trp were also modified, indicating that elimination of the gene TnaB contributed to the extracellular accumulation of L-trp. Through optimizing formulas, the robustness and production efficiency of engineered strains were enhanced at the level of the 30 L fermenter. After 42 h of fed-batch fermentation, the resultant strain produced 53.65 g/L of L-trp, with a yield of 0.238 g/g glucose. In this study, the high-efficiency L-trp-producing strains were created in order to establish a basis for further development of more strains for the production of other highly valuable aromatic compounds or their derivatives.


Assuntos
Proteínas de Escherichia coli , Escherichia coli , Escherichia coli/genética , Escherichia coli/metabolismo , Triptofano/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Engenharia Metabólica , Fermentação
18.
Life Sci Alliance ; 6(10)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429639

RESUMO

The histone demethylase Lsd1 has been shown to play multiple essential roles in mammalian biology. However, its physiological functions in thymocyte development remain elusive. We observed that the specific deletion of Lsd1 in thymocytes caused significant thymic atrophy and reduced peripheral T cell populations with impaired proliferation capacity. Single-cell RNA sequencing combined with strand-specific total RNA-seq and ChIP-seq analysis revealed that ablation of Lsd1 led to the aberrant derepression of endogenous retroelements, which resulted in a viral mimicry state and activated the interferon pathway. Furthermore, the deletion of Lsd1 blocked the programmed sequential down-regulation of CD8 expression at the DP→CD4+CD8lo stage and induced an innate memory phenotype in both thymic and peripheral T cells. Single-cell TCR sequencing revealed the kinetics of TCR recombination in the mouse thymus. However, the preactivation state after Lsd1 deletion neither disturbed the timeline of TCR rearrangement nor reshaped the TCR repertoire of SP cells. Overall, our study provides new insight into the function of Lsd1 as an important maintainer of endogenous retroelement homeostasis in early T-cell development.


Assuntos
Interferons , Retroelementos , Camundongos , Animais , Retroelementos/genética , Timo , Diferenciação Celular/genética , Receptores de Antígenos de Linfócitos T , Mamíferos
19.
Small Methods ; 7(10): e2300409, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37317015

RESUMO

Linear-conjugated polymers (LCPs) are excellent semiconductor photocatalysts. However, its inherent amorphous structures and simple electron transport channels restrict efficient photoexcited charge separation and transfer. Herein, "2D conjugated engineering" is employed to design high-crystalline polymer photocatalysts with multichannel charge transport by introducing alkoxyphenyl sidechains. The electronic state structure and electron transport pathways of the LCPs are investigated using experimental and theoretical calculations. Consequently, the 2D B←N-containing polymers (2DPBN) exhibit excellent photoelectric characteristics, which enable the efficient separation of electron-hole and rapidly transfer photogenerated carriers to the catalyst surface for efficient catalytic reactions. Significantly, the further hydrogen evolution of 2DPBN-4F heterostructures can be achieved by increasing the fluorine content of the backbones. This study highlights that the rational design of LCP photocatalysts is an effective strategy to spur further interest in photofunctional polymer material applications.

20.
Sci Total Environ ; 892: 164537, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37271405

RESUMO

Oxygen (O2) is essential for the survival and reproduction of most species. However, in recent years, with global climate change and the increasing impact of human activities on the ecosystem, the frequency of extreme environmental events, such as heat waves, cold waves, droughts, and floods, has increased, resulting in dramatic changes in environmental oxygen concentration (hypoxic environment, etc.), threatening the survival of animals and pushing them toward extreme adaptation. In this context, how organisms, especially those with differences in original habitats, adapt to low oxygen environment is particularly important. In this study, we systematically analyzed hypoxic response patterns in lung tissues of small rodents Neodon fuscus, Lasiopodomys brandtii, and Mus musculus with different experiences of natural hypoxia tolerance through laboratory simulation of hypoxia environment, combined with hematological, histological, and transcriptomic analysis. Our results show that all three species exhibit increased antioxidant defense and damage repair ability to a certain extent under hypoxia, although the specific molecular mechanisms are not the same. L. brandtii showed better damage repair ability than the others, which is likely to be closely related to the intermittent hypoxia environment experienced in the natural environment, and genes such as Glrx5, Prdx2, Col1a1, Lama1, and Eln may play a crucial role in this process. In addition, we found that both N. fuscus and L. brandtii appropriately enhanced oxygen transport in tissues under hypoxic conditions, with a series of functional genes related to hemoglobin synthesis and vascular smooth muscle contraction were significantly up-regulated in both species of voles, such as Actg2, Ptgir, Alas2, Hba, Hbb and Bpgm. Our results, to a certain extent, reveal the differences and similarities of hypoxic response patterns in lung tissues of small rodents with different hypoxic life histories and provide a relatively perfect analytical paradigm for related studies.


Assuntos
Ecossistema , Transcriptoma , Animais , Humanos , Hipóxia , Oxigênio , Arvicolinae/genética , Pulmão
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