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Objective: This study aimed to evaluate the effectiveness of oral L-carnitine administration in patients after treatment failure to lay the groundwork for targeted in vivo use. Methods and materials: A total of 515 In Vitro Fertilization (IVF) patients undergoing subsequent cycles were included after applying exclusion criteria. They were divided into a control group of 362 patients and a study group of 153 patients who received oral L-carnitine until oocyte retrieval.140 patients were matched according to maternal age, infertility duration, body mass index (BMI), day three top-quality embryos rate, by propensity score matching (PSM). The study investigated the relationship between L-carnitine treatment and in vivo oocyte maturation, normal fertilization, and subsequent embryo development. Results: Following PSM, initial differences in BMI and Day3 top-quality embryo rate between groups were nullified, we created two comparable cohorts with highly similar characteristics. In the subsequent cycles, the study group showed significant improvements in in vivo oocyte maturation rate at retrieval (p=0.002), normal in vitro fertilization rate (p=0.003), blastocyst formation rate (p=0.003), and usable blastocyst rate compared to controls. Although there was no significant difference in the top-quality embryo rate on Day 3, the study group showed a 10% increase in the upper quartile (55.35% vs. 66.67%). The cumulative clinical pregnancy and live birth rates showed a significant improvement (59.82% vs. 68.42%,p=0.004, 47.41% vs. 59.80%, p=0.002). Furthermore, self-control analysis revealed substantial enhancements (p<0.001) in all outcome measures following L-carnitine administration, resulting in the birth of 74 healthy neonates without congenital anomalies. Conclusion: We theorized that daily oral intake of L-carnitine before oocyte retrieval could boost oocyte quality and embryonic development, thus improving IVF outcomes. Ongoing investigations hold the potential to offer valuable insights into the applications and mechanisms underlying the therapeutic effectiveness of L-carnitine.
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Carnitina , Fertilização in vitro , Pontuação de Propensão , Humanos , Carnitina/administração & dosagem , Feminino , Adulto , Fertilização in vitro/métodos , Gravidez , Administração Oral , Taxa de Gravidez , Recuperação de Oócitos/métodos , Infertilidade Feminina/tratamento farmacológico , Doenças Ovarianas/tratamento farmacológico , Resultado do Tratamento , Estudos RetrospectivosRESUMO
BACKGROUND: Extrathyroidal extension was related with worse survival for patients with papillary thyroid carcinoma. For its preoperative evaluation, we measured and compared the predicting value of sonographic method and ultrasonic radiomics method in nodules of papillary thyroid carcinoma. PATIENTS AND METHODS: Data from 337 nodules were included and divided into training group and validation group. For ultrasonic radiomics method, a best model was constructed based on clinical characteristics and ultrasonic radiomic features. The predicting value was calculated then. For sonographic method, the results were calculated using all samples. RESULTS: For ultrasonic radiomics method, we constructed 9 models and selected the extreme gradient boosting model for its highest accuracy (0.77) and area under curve (0.813) in validation group. The accuracy and area under curve of sonographic method was 0.70 and 0.569. Meanwhile. We found that the top-6 important features of xgboost model included no clinical characteristics, all of whom were high-dimensional radiomic features. CONCLUSIONS: The study showed the superior value of ultrasonic radiomics method to sonographic method for preoperative detection of extrathyroidal extension in papillary thyroid carcinoma. Furthermore, high-dimensional radiomic features were more important than clinical characteristics.
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Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Ultrassonografia , Humanos , Estudos Retrospectivos , Feminino , Masculino , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/patologia , Ultrassonografia/métodos , Câncer Papilífero da Tireoide/diagnóstico por imagem , Câncer Papilífero da Tireoide/patologia , Pessoa de Meia-Idade , Adulto , Idoso , Invasividade Neoplásica/diagnóstico por imagem , Valor Preditivo dos Testes , RadiômicaRESUMO
The surge in demand for experimental monkeys has led to a rapid increase in their costs. Consequently, there is a growing need for a cost-effective model of Parkinson's disease (PD) that exhibits all core clinical and pathological phenotypes. Evolutionarily, tree shrews (Tupaia belangeri) are closer to primates in comparison to rodents and could be an ideal species for modeling PD. To develop a tree shrew PD model, we used the 1-methyl-4-phenylpyridinium (MPP+), a metabolite derived from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), to induce lesions in dopaminergic neurons of the unilateral substantia nigra. The induced tree shrew model consistently exhibited and maintained all classic clinical manifestations of PD for a 5-month period. The symptoms included bradykinesia, rest tremor, postural instability, and about 50% individuals showed apomorphine-induced rotations, a classic phenotype of unilateral PD models. All these are closely resembled the ones observed in PD monkeys. Meanwhile, this model was also sensitive to L-dopa treatment with a dose dependent manner, which suggested that the motor deficits are dopamine dependent. Immunostaining showed a significant loss of dopaminergic neurons (approximately 95%) in the lesioned substantia nigra, which is a crucial PD pathological marker. Moreover, a control group of nigral saline injection did not show any motor deficits and pathological changes. Cytomorphological analysis revealed that the size of nigral dopaminergic neurons in tree shrews is much bigger than that of rodents and is close to that of macaques. The morphological similarity may be an important structural basis for the manifestation of the highly similar phenotypes between monkey and tree shrew PD models. Collectively, in this study we have successfully developed a PD model in a small animal species that faithfully recapitulated the classic clinical symptoms and key pathological indicators of PD monkeys, providing a novel and low-cost avenue for evaluation of PD treatments and underlying mechanisms.
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More and more attention has been paid to food safety. Due to the overuse and misuse of antibiotics, the problem of antibiotic residues in animal food is one of the important challenges to ensure food safety. The development of a feasible strategy to detect antibiotic residues in animal food has become desirable. In this paper, we creatively synthesize a water-stable fluorescence sensing material, namely, Co(â ¡)-Coordination polymer [Co2(CA) (L)0.5 (H2O)3] n (L = 1,4-bis(imidazole-1-ylmethyl) benzene, CA= Citric acid). The single crystal X-ray diffraction shows that it crystallizes in tetragonal space group I-4. It is worth mentioning that there exists the rare Co4(µ3-O)4 cubane cluster structure and Co8 cluster units. Those adjacent Co8 cluster units are connected into an infinite two-dimensional net structure by four flexible bridged L ligands. Finally, the Co(â ¡)-Coordination polymer (CP) further develops into the three-dimensional supramolecular structure via the hydrogen bonds of O-Hâ¯O and C-Hâ¯O. It could selectively detect the antibiotic-nitrofurantoin (NFT) residue by way of fluorescence quenching, Co-CP for the detection of NFT shows broad linearity from 0 to 200 µM, with a detection limit of 0.13 µM and strong anti-interference ability. It is used to detect the NFT residual of tap water and milk with a spiked recovery of 86.35-112.47 %.
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Antibacterianos , Cobalto , Complexos de Coordenação , Corantes Fluorescentes , Nitrofurantoína , Polímeros , Cobalto/química , Cobalto/análise , Antibacterianos/análise , Antibacterianos/química , Polímeros/química , Nitrofurantoína/análise , Nitrofurantoína/química , Corantes Fluorescentes/química , Complexos de Coordenação/química , Espectrometria de Fluorescência/métodos , Animais , Leite/química , Modelos Moleculares , Contaminação de Alimentos/análise , FluorescênciaRESUMO
Porcine reproductive and respiratory syndrome virus (PRRSV) is a severe disease with substantial economic consequences for the swine industry. The DEAD-box helicase 3 (DDX3X) is an RNA helicase that plays a crucial role in regulating RNA metabolism, immunological response, and even RNA virus infection. However, it is unclear whether it contributes to PRRSV infection. Recent studies have found that the expression of DDX3X considerably increases in Marc-145 cells when infected with live PRRSV strains Ch-1R and SD16; however, it was observed that inactivated viruses did not lead to any changes. By using the RK-33 inhibitor or DDX3X-specific siRNAs to reduce DDX3X expression, there was a significant decrease in the production of PRRSV progenies. In contrast, the overexpression of DDX3X in host cells substantially increased the proliferation of PRRSV. A combination of transcriptomics and metabolomics investigations revealed that in PRRSV-infected cells, DDX3X gene silencing severely affected biological processes such as ferroptosis, the FoxO signalling pathway, and glutathione metabolism. The subsequent transmission electron microscopy (TEM) imaging displayed the typical ferroptosis features in PRRSV-infected cells, such as mitochondrial shrinkage, reduction or disappearance of mitochondrial cristae, and cytoplasmic membrane rupture. Conversely, the mitochondrial morphology was unchanged in DDX3X-inhibited cells. Furthermore, silencing of the DDX3X gene changed the expression of ferroptosis-related genes and inhibited the virus proliferation, while the drug-induced ferroptosis inversely promoted PRRSV replication. In summary, these results present an updated perspective of how PRRSV infection uses DDX3X for self-replication, potentially leading to ferroptosis via various mechanisms that promote PRRSV replication.
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RNA Helicases DEAD-box , Ferroptose , Vírus da Síndrome Respiratória e Reprodutiva Suína , Replicação Viral , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Animais , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Ferroptose/fisiologia , Suínos , Síndrome Respiratória e Reprodutiva Suína/virologia , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Linhagem CelularRESUMO
We delve into the critical role of the gut microbiota and its metabolites in the pathogenesis and progression of hepatobiliary and pancreatic (HBP) cancers, illuminating an urgent need for breakthroughs in diagnostic and therapeutic strategies. Given the high mortality rates associated with HBP cancers, which are attributed to aggressive recurrence, metastasis, and poor responses to chemotherapy, exploring microbiome research presents a promising frontier. This research highlights how microbial metabolites, including secondary bile acids, short-chain fatty acids, and lipopolysaccharides, crucially influence cancer cell behaviors such as proliferation, apoptosis, and immune evasion, significantly contributing to the oncogenesis and progression of HBP cancers. By integrating the latest findings, we discuss the association of microbial alterations with HBP cancers, key metabolites, and their implications, and how metabolomics and microbiomics can enhance diagnostic precision. Furthermore, the paper explores strategies for targeted therapies through microbiome metabolomics, including the direct therapeutic effects of microbiome metabolites and potential synergistic effects on conventional therapies. We also recognize that the field of microbial metabolites for the diagnosis and treatment of tumors still has a lot of problems to be solved. The aim of this study is to pioneer microbial metabolite research and provide a reference for HBP cancer diagnosis, treatment, and prognosis.
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Microbioma Gastrointestinal , Metaboloma , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/microbiologia , Animais , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/microbiologia , Metabolômica/métodos , Medicina de Precisão , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/diagnóstico , Neoplasias do Sistema Biliar/metabolismo , Neoplasias do Sistema Biliar/microbiologiaRESUMO
Diphenylalanine(FF)-Zn self-assembly (FS) confined in covalent organic polymers (FS@COPs) with efficient fluorescence was synthesized for fluorescence sensing of biogenic amines, which was one of the most important indicators for monitoring food freshness. FS@COPs combined excellent biodegradability of self-assembled dipeptide with chemical stability, porosity and targeted site recognition of COPs. With an optimal excitation wavelength of 360 nm and an optimal emission wavelength of 450 nm, FS@COPs could be used as fluorescence probes to rapidly visualize and highly sensitive determination of tryptamine (Try) within 15 min, and the linear range was from 40 to 900 µg L-1 with a detection limit of 63.08 µg kg-1. Importantly, the FS@COPs showed a high fluorescence quantum yield of 11.28%, and good stability, solubility, and selectivity, which could successfully achieve the rapid, accurate and highly sensitive identification of Try. Furthermore, we revealed the mechanism of FS@COPs for fluorescence sensing of targets. The FS@COPs system was applied to the fluorescence sensing of Try in real samples and showed satisfactory accuracy of 93.02%-105.25%.
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Dipeptídeos , Corantes Fluorescentes , Limite de Detecção , Espectrometria de Fluorescência , Triptaminas , Triptaminas/análise , Triptaminas/química , Dipeptídeos/química , Dipeptídeos/análise , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Produtos da Carne/análise , Polímeros/químicaRESUMO
Work function (WF) is one of the most fundamental physical parameters of metal surfaces, which can not only reflect the electronic structure of metal surfaces but is also very sensitive to the surface microstructure. In this paper, we use first-principles calculations to systematically study the strain effects on the vacuum level, Fermi level, and WF of the Au(111) surface. We find that the vacuum level and Fermi level of the Au(111) surface increase under compressive strain and decrease under tensile strain, and the effects of biaxial strain on the vacuum level and Fermi level can be equivalent to the superposition of two perpendicular uniaxial strains. These strain effects are attributed to the charge transfer induced by the strain. However, the change of WF with strain is the result of the competition between the strain effects of the vacuum level and Fermi level. That leads to the WF increasing with compressive uniaxial strain and decreasing with tensile uniaxial strain. Moreover, because the Fermi level is more responsive to compressive uniaxial strain, the Fermi level changes faster than the vacuum level under compressive biaxial strain. Consequently, the WF decreases with increasing tensile biaxial strain and slightly increases before decreasing with increasing compressive biaxial strain.
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[This retracts the article DOI: 10.3892/ol.2020.11687.].
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BACKGROUND: Patients with pancreatic ductal adenocarcinoma (PDAC) display an altered oral, gastrointestinal, and intra-pancreatic microbiome compared to healthy individuals. However, knowledge regarding the bile microbiome and its potential impact on progression-free survival in PDACs remains limited. METHODS: Patients with PDAC (n = 45), including 20 matched pairs before and after surgery, and benign controls (n = 16) were included prospectively. The characteristics of the microbiomes of the total 81 bile were revealed by 16 S-rRNA gene sequencing. PDAC patients were divided into distinct groups based on tumor marker levels, disease staging, before and after surgery, as well as progression free survival (PFS) for further analysis. Disease diagnostic model was formulated utilizing the random forest algorithm. RESULTS: PDAC patients harbor a unique and diverse bile microbiome (PCoA, weighted Unifrac, p = 0.038), and the increasing microbial diversity is correlated with dysbiosis according to key microbes and microbial functions. Aliihoeflea emerged as the genus displaying the most significant alteration among two groups (p < 0.01). Significant differences were found in beta diversity of the bile microbiome between long-term PFS and short-term PFS groups (PCoA, weighted Unifrac, p = 0.005). Bacillota and Actinomycetota were identified as altered phylum between two groups associated with progression-free survival in all PDAC patients. Additionally, we identified three biomarkers as the most suitable set for the random forest model, which indicated a significantly elevated likelihood of disease occurrence in the PDAC group (p < 0.0001). The area under the receiver operating characteristic (ROC) curve reached 80.8% with a 95% confidence interval ranging from 55.0 to 100%. Due to the scarcity of bile samples, we were unable to conduct further external verification. CONCLUSION: PDAC is characterized by an altered microbiome of bile ducts. Biliary dysbiosis is linked with progression-free survival in all PDACs. This study revealed the alteration of the bile microbiome in PDACs and successfully developed a diagnostic model for PDAC.
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Bile , Carcinoma Ductal Pancreático , Microbiota , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/microbiologia , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Bile/microbiologia , Masculino , Feminino , Neoplasias Pancreáticas/microbiologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Microbiota/genética , Pessoa de Meia-Idade , Idoso , Disbiose/microbiologia , Intervalo Livre de Progressão , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Estudos Prospectivos , RNA Ribossômico 16S/genéticaRESUMO
A fluorescence probe based on molecularly imprinted polymers on red emissive biomass-derived carbon dots (r-BCDs@MIPs) was developed to detect tyramine in fermented meat products. The red emissive biomass-derived carbon dots (r-BCDs) were synthesized by the one-step solvothermal method using discarded passion fruit shells as raw materials. The fluorescence emission peak of r-BCDs was at 670 nm, and the relative quantum yield (QY) was about 2.44%. Molecularly imprinted sensing materials were prepared with r-BCDs as fluorescent centers for the detection of trace tyramine, which showed a good linear response in the concentration range of tyramine from 1 to 40 µg L-1. The linear correlation coefficient was 0.9837, and the limit of detection was 0.77 µg L-1. The method was successfully applied to the determination of tyramine in fermented meat products, and the recovery was 87.17-106.02%. The reliability of the results was verified through high-performance liquid chromatography (HPLC). Furthermore, we combined the r-BCDs@MIPs with smartphone-assisted signal readout to achieve real-time detection of tyramine in real samples. Considering its simplicity and convenience, the method could be used as a rapid and low-cost promising platform with broad application prospects for on-site detection of trace tyramine with smartphone-assisted signal readout.
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Carbono , Corantes Fluorescentes , Limite de Detecção , Produtos da Carne , Polímeros Molecularmente Impressos , Pontos Quânticos , Smartphone , Tiramina , Tiramina/análise , Tiramina/química , Carbono/química , Pontos Quânticos/química , Produtos da Carne/análise , Corantes Fluorescentes/química , Polímeros Molecularmente Impressos/química , Espectrometria de Fluorescência/métodos , Biomassa , FermentaçãoRESUMO
The synthesis of a specific product via the Fischer-Tropsch synthesis remains challenging due to the uncontrollable coupling of CHx on active sites. Isoparaffins, essential high-quality petroleum additives for improving octane numbers, are primarily derived from petroleum or natural gas. With petroleum reserves dwindling and the associated low selectivity, the direct conversion of syngas to isoparaffins has emerged as a promising alternative. This study presents a tandem catalyst comprising CoxMn1-xO and zeolites for catalyzing the direct conversion of syngas to C4-C5 isoparaffins. The relay catalyst exhibited an impressive selectivity of 55.6% toward the desired products while maintaining a low CO2 selectivity of approximately 20%. Notably, the selectivity of isobutane reached 43.5%, exceeding predictions based on the Anderson-Schulz-Flory distribution. Syngas undergoes conversion into olefins on CoxMn1-xO nanocomposites, diffuses into microporous zeolites, and interacts with Brønsted acids to produce isoparaffins. The stability of the relay catalyst relied significantly on the pore characteristics and acidic density of the zeolites.
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Purpose: The purpose of this study was to investigate the spatial distribution of human cone photoreceptors and examine cone density differences between the retinal meridians and quadrants. Method: Using adaptive optics scanning laser ophthalmoscopy, the maculae were imaged in 17 eyes of 11 subjects with normal chorioretinal health aged 54 to 72 years. We measured cone density at 325 points within the central 10 degrees radius of the retina. Cone density spatial distributions along the primary retinal meridians and in four macular quadrants (superior-nasal, superior-temporal, inferior-temporal, and inferior-nasal) were analytically modeled using the polynomial function to assess the meridional and quadrantal difference. Results: The mean and 95% confidence interval for the prediction of cone density along the primary retinal meridians was modeled with a 7-degree one-variable polynomial (R2 = 0.9761, root mean squared error [RMSE] = 0.0585). In the 4 retinal quadrants, cone density distribution was described by a 2-variable polynomial with X degree 3 and Y degree 4 (R² = 0.9834, RMSE = 0.0377). The models suggest no statistically significant difference between medians and between quadrants. However, cone density difference at corresponding spatial locations in different areas can be up to 25.6%. The superior-nasal region has more areas with high cone density, followed by quadrants of inferior-nasal, inferior-temporal, and superior-temporal. Conclusions: Analytical modeling provides comprehensive knowledge of cone distribution across the entire macula. Although modeling analysis suggests no statistically significant difference between medians and between quadrants, the remarkable cone density discrepancies in certain regions should be accounted for in applications requiring sensitive detection of cone variation.
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Oftalmoscopia , Células Fotorreceptoras Retinianas Cones , Humanos , Células Fotorreceptoras Retinianas Cones/citologia , Pessoa de Meia-Idade , Idoso , Masculino , Feminino , Oftalmoscopia/métodos , Contagem de Células , Macula Lutea/diagnóstico por imagemRESUMO
This study explores the potential role and mechanism of Ginsenoside Rb3 (Rb3) in modulating osteoclastogenesis induced by human periodontal ligament fibroblasts (hPLFs) within the periodontitis microenvironment. We investigated the anti-inflammatory effects of Rb3 on hPLFs stimulated with Porphyromonas gingivalis lipopolysaccharide (P.g-LPS) utilizing quantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay techniques. Moreover, the functional role of Rb3 in hPLFs-induced osteoclast formation was assessed by treating human bone marrow-derived macrophages (hBMMs) with conditioned medium from hPLFs, followed by analyses through qPCR, western blot analysis, and staining for tartrate-resistant acid phosphatase (TRAP) and phalloidin. The impact of Rb3 on the activation of the STAT3 signaling pathway was determined via western blot analysis. Results indicated that Rb3 treatment significantly suppressed the upregulation of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6, MCP-1, and IL-18) at both gene and protein levels in hPLFs induced by P.g-LPS. Furthermore, conditioned medium from Rb3 plus P.g-LPS treated hPLFs notably decreased the number of TRAP-positive cells, actin ring formations, and the expression of osteoclast marker genes (including CTSK, NFATC1, and ACP5). Rb3 also inhibited the P.g-LPS-induced activation of the STAT3 pathway, with the activation of STAT3 partially reversing the effects of Rb3 on inflammation and osteoclast differentiation. Collectively, Rb3 ameliorates inflammation in P.g-LPS-stimulated hPLFs and reduces hPLFs-induced osteoclastogenesis by inhibiting the STAT3 signaling pathway, suggesting its potential as a therapeutic agent for periodontitis.
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Fibroblastos , Ginsenosídeos , Osteoclastos , Ligamento Periodontal , Periodontite , Fator de Transcrição STAT3 , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Ginsenosídeos/farmacologia , Humanos , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Ligamento Periodontal/citologia , Ligamento Periodontal/metabolismo , Ligamento Periodontal/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Periodontite/metabolismo , Periodontite/tratamento farmacológico , Células Cultivadas , Osteogênese/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Porphyromonas gingivalis , Microambiente Celular/efeitos dos fármacos , Citocinas/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacosRESUMO
Aim: Serotype-specific assays detecting pneumococcal polysaccharides in bodily fluids are needed to understand the pneumococcal serotype distribution in non-bacteremic pneumonia.Methods: We developed a urine antigen detection assay and using urine samples from adult outpatients without pneumonia developed positivity cutoffs for both a previously published 15-valent and the new 21-valent assay. Clinical sensitivity was confirmed with samples from patients with invasive pneumococcal disease.Results: Total assay precision ranged from 7.6 to 17.8% coefficient of variation while accuracy ranged between 80 and 150% recovery, except for three serotypes where recoveries ranged from 32 to 60%. Clinical sensitivity was 86.4% and specificity was 96.5% across all 30 serotypes.Conclusion: The assay could potentially assess serotype-distribution in non-infected and infected participants with pneumococcal disease.
[Box: see text].
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Antígenos de Bactérias , Streptococcus pneumoniae , Humanos , Streptococcus pneumoniae/imunologia , Streptococcus pneumoniae/isolamento & purificação , Antígenos de Bactérias/urina , Adulto , Infecções Pneumocócicas/urina , Infecções Pneumocócicas/diagnóstico , Infecções Pneumocócicas/microbiologia , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
L-asparaginase synthetase, an ATP-dependent enzyme, necessitates ATP for its catalytic activity. However, the integration of L-asparaginase synthetase into industrial processes is curtailed by the prohibitive cost of ATP. To address this limitation, this study explores the construction of an efficient ATP regeneration system using the glucose metabolism of Escherichia coli, synergistically coupled with L-asparaginase synthetase catalysis. The optimal conditions for L-asparagine yield were determined in shake flasks. A total of 2.7 g/L was the highest yield achieved under specific parameters, including 0.1 mol/L of substrate, 0.2 mol/L glucose, 0.01 mol/L MgCl2 at pH 7.5, a temperature of 37 °C, and agitation at 300 r/min over 12 h. The process was then scaled to a 3-L fermenter, optimizing the addition rates of the substrate and magnesium chloride, and employing a constant glucose feed of 10 g/L/h. The scale-up process led to a significant enhancement in the production of L-asparagine. The yield of L-asparagine was increased to 38.49 g/L after 20 h of conversion, and the molar conversion rate reached 29.16%. This strategy has proven to be effective in improving the efficiency of L-asparagine production. When compared to in vitro ATP regeneration methods, this in vivo approach showcased superior efficiency and reduced costs. These findings furnish pivotal insights that may propel the enzymatic synthesis of L-asparagine toward viable industrial application.
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Single-atom catalysts (SACs) are attractive in one-carbon (C1) chemistry because of their high atom efficiency. However, it is a great challenge for understanding the dynamic roles of SACs under operating conditions. Here, isolated Pt atoms trapped on defective CeO2 surface are investigated by experiments, especially operando techniques, which offers basic understanding of the nature and dynamic evolution of the Pt-CeO2 interface in dry reforming of methane (DRM). The Pt-Olattice configuration is highly active for CH4 dissociation at the expense of the Olattice atoms, which in turn promotes the H-assisted dissociation of CO2. The transformation of Pt atoms between positive and metallic states is driven by the DRM reaction, which is essential for rendering highly efficient catalysis. The dynamic evolution of Pt atoms favors to eliminate the reactive intermediates, such as carbonates and formates. The dynamic nature of the Pt-CeO2 interface in the DRM reaction shows a similar picture to the Yin and Yang transformation in ancient Chinese Tai Ji wisdom.
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Musicoterapia , Manejo da Dor , Humanos , Manejo da Dor/métodos , Dor/prevenção & controle , Dor/etiologiaRESUMO
Lead and its compounds can have cumulative harmful effects on the nervous, cardiovascular, and other systems, and especially affect the brain development of children. We collected 4918 samples from 15 food categories in 11 districts of Guangzhou, China, from 2017 to 2022, to investigate the extent of lead contamination in commercial foods and assess the health risk from dietary lead intake of the residents. Lead was measured in the samples using inductively coupled plasma mass spectrometry. Dietary exposure to lead was calculated based on the food consumption survey of Guangzhou residents in 2011, and the health risk of the population was evaluated using the margin of exposure (MOE) method. Lead was detected in 76.5% of the overall samples, with an average lead content of 29.4 µg kg-1. The highest lead level was found in bivalves. The mean daily dietary lead intakes were as follows: 0.44, 0.34, 0.25, and 0.28 µg kg-1 body weight (bw) day-1 for groups aged 3-6, 7-17, 18-59, and ≥ 60 years, respectively. Rice and rice products, leafy vegetables, and wheat flour and wheat products were identified as the primary sources of dietary lead exposure, accounting for 73.1%. The MOE values demonstrated the following tendency: younger age groups had lower MOEs, and 95% confidence ranges for the groups aged 3-6 and 7-17 began at 0.6 and 0.7, respectively, indicating the potential health risk of children, while those for other age groups were all above 1.0. Continued efforts are needed to reduce dietary lead exposure in Guangzhou.
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Exposição Dietética , Contaminação de Alimentos , Chumbo , Chumbo/análise , China , Humanos , Medição de Risco , Exposição Dietética/análise , Contaminação de Alimentos/análise , Criança , Adolescente , Pré-Escolar , Adulto , Adulto Jovem , Pessoa de Meia-Idade , Probabilidade , Feminino , MasculinoRESUMO
A ratiometric fluorescence molecularly imprinted probe employing two distinct emission wavelengths of biomass carbon dots was developed for highly selective and visual quantitative detection of tyramine in fermented meat products. The red emission biomass carbon dots were employed as responsive elements, and the blue ones were utilized as the reference elements. The molecularly imprinted polymers were incorporated in the ratiometric sensing to distinguish and adsorb tyramine. With the linear range of 1-60 µg/L, the ratiometric fluorescence molecularly imprinted probe was successfully applied to detect tyramine in real samples with the satisfactory recoveries of 79.74-112.12% and the detect limitation of 1.3 µg/kg, indicating that this probe has great potential applications for the detection of tyramine in real samples. Moreover, smartphone-based fluorescence signal recognition analysis on hand has been developed for the quantitative analysis of tyramine, providing a portable visual optical analysis terminal for rapid on-site determination of tyramine.