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1.
BMC Nephrol ; 25(1): 209, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918687

RESUMEN

BACKGROUND: Autosomal recessive polycystic kidney disease (ARPKD) is a rare inherited cystic disease characterized by bilateral renal cyst formation and congenital liver fibrosis. Cardiovascular disorders such as noncompaction of ventricular myocardium (NVM) have not been reported with ARPKD. CASE PRESENTATION: A 5-month-old girl was examined after presenting with a fever and turbid urine for one day and was diagnosed as urinary tract infection. Urinary ultrasound showed multiple round, small cysts varying in size in both kidneys. Genetic testing revealed two heterozygous mutations and one exon deletion in the polycystic kidney and hepatic disease 1 gene, indicating a diagnosis of ARPKD. During hospitalization, she was found to have chronic heart failure after respiratory tract infection, with an ejection fraction of 29% and fraction shortening of 13%. When the patient was 15 months old, it was found that she had prominent trabeculations and deep intertrabecular recesses with the appearance of blood flow from the ventricular cavity into the intertrabecular recesses by echocardiography. The noncompaction myocardium was 0.716 cm and compaction myocardium was 0.221 cm (N/C = 3.27), indicating a diagnosis of NVM. Liver and kidney function remained normal during four-year follow-up. CONCLUSIONS: This is the first report of NVM in a patient with ARPKD. It is unsure if the coexistence of NVM and ARPKD is a coincidence or they are different manifestations of ciliary dysfunction in the heart and kidneys.


Asunto(s)
Riñón Poliquístico Autosómico Recesivo , Humanos , Femenino , Riñón Poliquístico Autosómico Recesivo/complicaciones , Riñón Poliquístico Autosómico Recesivo/genética , Riñón Poliquístico Autosómico Recesivo/diagnóstico por imagen , Lactante , No Compactación Aislada del Miocardio Ventricular/complicaciones , No Compactación Aislada del Miocardio Ventricular/genética , No Compactación Aislada del Miocardio Ventricular/diagnóstico por imagen , Ciliopatías/genética , Ciliopatías/complicaciones
2.
Eur J Surg Oncol ; 50(9): 108474, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38870874

RESUMEN

BACKGROUND: Colorectal cancer (CRC) patients with peritoneal metastasis (CRC-PM) have a worse prognosis than those with liver and lung metastases. Cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is an effective locoregional treatment for CRC-PM. To date, the prognostic analysis of CRS/HIPEC mostly focuses on clinical and pathological characteristics; however, genetic characteristics, such as RAS/BRAF mutation status, are not sufficient. This study aimed to systematically assess the correlation between RAS/BRAF status and PM risk, as well as the prognostic efficacy of CRS/HIPEC for CRC. METHOD: This study was written in accordance with the 2020 guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols. We searched PubMed, EMBASE, and the Cochrane library with the following keywords: "Peritoneal Neoplasms," "raf Kinases" and "ras Proteins". The fixed-effects model and inverse variance method were used for analysis. Odds ratios (OR) and 95 % confidence intervals (CI) were used to reflect the risk of PM associated with RAS/BRAF mutations. Hazard ratios (HR) and 95 % CI were used to evaluate the effects of RAS/BRAF mutations on the prognosis of CRS/HIPEC. RESULT: Eighteen articles included 5567 patients. In the risk analysis of PM, patients with BRAF mutation were more likely to have PM than those with wild-type BRAF (OR = 2.28, 95 % CI = 1.73-3.01, P < 0.001, I2 = 0 %). In contrast, there was no significant difference in the effect of RAS mutation and wild-type on PM of CRC (OR = 1.28, 95 % CI = 0.99-1.66, P = .06, I2 = 0 %). In a prognostic analysis of CRS/HIPEC, RAS mutation predicted poor overall survival (HR = 1.68, 95 % CI = 1.39-2.02, P < 0.001, I2 = 1 %) and disease-free survival (HR = 1.61, 95 % CI = 1.34-1.94, P < 0.001, I2 = 42 %). The results for BRAF mutation was consistent with the prognostic impact of RAS mutation's overall survival (HR = 2.57, 95 % CI = 1.93-3.44, P < 0.001, I2 = 0 %) and disease-free survival (HR = 1.90, 95 % CI = 1.40-2.56, P < 0.001, I2 = 82 %). CONCLUSION: BRAF mutation, rather than RAS mutation, was a high-risk factor for CRC-PM. And both BRAF and RAS mutations negatively affected the prognosis of CRS/HIPEC in CRC-PM patients. Our results could provide suggestions for the selection of comprehensive treatment for CRC-PM with RAS/BRAF mutations.

3.
Anal Chem ; 96(26): 10577-10585, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38887964

RESUMEN

Simultaneous detection of multiple breast cancer-associated miRNAs significantly raises the accuracy and reliability of early diagnosis. In this work, disposable carbon fiber paper serves as the biosensing interface, linking DNA probes via click chemistry to efficiently capture targets and signals efficiently. DNA probes have multiple recognition domains that trigger a cascade reaction through the helper probes and targets, resulting in two signals output. The signals are centrally encapsulated in the pore of the MIL-88(Fe)-NH2. The signal carriers are directed by signal probes to the recognition domains that correspond to the DNA probes. The biosensor is selective and stable, and it can quantify miRNA-21 and miRNA-155 simultaneously with detection limits of 0.64 and 0.54 fmol/L, respectively. Furthermore, it demonstrates satisfactory performance in tests conducted with normal human serum and cell lysate. Overall, this method makes a satisfactory exploration to realize an inexpensive and sensitive biosensor for multiple biomarkers.


Asunto(s)
Técnicas Biosensibles , Química Clic , MicroARNs , Técnicas Biosensibles/métodos , Humanos , MicroARNs/análisis , MicroARNs/sangre , Sondas de ADN/química , Neoplasias de la Mama/diagnóstico , Límite de Detección
4.
Int Immunopharmacol ; 137: 112443, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38897124

RESUMEN

Brucella is an intracellular parasitic bacterium lacking typical virulence factors, and its pathogenicity primarily relies on replication within host cells. In this study, we observed a significant increase in spleen weight in mice immunized with a Brucella strain deleted of the gene for alanine racemase (Alr), the enzyme responsible for alanine racemization (Δalr). However, the bacterial load in the spleen markedly decreased in the mutant strain. Concurrently, the ratio of white pulp to red pulp in the spleen was increased, serum IgG levels were elevated, but no significant damage to other organs was observed. In addition, the inflammatory response was potentiated and the NF-κB-NLRP3 signaling pathway was activated in macrophages (RAW264.7 Cells and Bone Marrow-Derived Cells) infect ed with the Δalr mutant. Further investigation revealed that the Δalr mutant released substantial amounts of protein in a simulated intracellular environment which resulted in heightened inflammation and activation of the TLR4-NF-κB-NLRP3 pathway in macrophages. The consequent cytoplasmic exocytosis reduced intracellular Brucella survival. In summary, cytoplasmic exocytosis products resulting from infection with a Brucella strain deleted of the alr gene effectively activated the TLR4-NFκB-NLRP3 pathway, triggered a robust inflammatory response, and reduced bacterial survival within host cells. Moreover, the Δalr strain exhibits lower toxicity and stronger immunogenicity in mice.

5.
Neurol Sci ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38902569

RESUMEN

OBJECTIVE: To describe the association between preoperative ictal scalp electroencephalogram (EEG) results and surgical outcomes in patients with focal epilepsies. METHODS: The data of consecutive patients with focal epilepsies who received surgical treatments at our center from January 2012 to December 2021 were retrospectively analyzed. RESULTS: Our data showed that 44.2% (322/729) of patients had ictal EEG recorded on video EEG monitoring during preoperative evaluation, of which 60.6% (195/322) had a concordant ictal EEG results. No significant difference of surgery outcomes between patients with and without ictal EEG was discovered. Among MRI-negative patients, those with concordant ictal EEG had a significantly better outcome than those without ictal EEG (75.7% vs. 43.8%, p = 0.024). Further logistic regression analysis showed that concordant ictal EEG was an independent predictor for a favorable outcome (OR = 4.430, 95%CI 1.175-16.694, p = 0.028). Among MRI-positive patients, those with extra-temporal lesions and discordant ictal EEG results had a worse outcome compared to those without an ictal EEG result (44.7% vs. 68.8%, p = 0.005). Further logistic regression analysis showed that discordant ictal EEG was an independent predictor of worse outcome (OR = 0.387, 95%CI 0.186-0.807, p = 0.011) in these patients. Furthermore, our data indicated that the number of seizures was not associated with the concordance rates of the ictal EEG, nor the surgical outcomes. CONCLUSIONS: The value of ictal scalp EEG for epilepsy surgery varies widely among patients. A concordant ictal EEG predicts a good surgical outcome in MRI-negative patients, whereas a discordant ictal EEG predicts a poor postoperative outcome in lesional extratemporal lobe epilepsy.

6.
Front Microbiol ; 15: 1395504, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38841069

RESUMEN

Persister cells are transiently tolerant to antibiotics and are associated with recalcitrant chronic infections due to recolonization of host cells after antibiotic removal. Brucella spp. are facultative pathogens that establish intracellular infection cycles in host cells which results in chronic persistent infections. Brucella abortus forms multi-drug persister cells which are promoted by the (p)ppGpp synthetase Rsh during rifampicin exposure. Here, we confirmed that Rsh promoted persister cells formation in B. abortus stationary phase treated with rifampicin and enrofloxacin. Deletion of the gene for Rsh decreased persister cells level in the presence of these drugs in different growth phases. However, persister cells formation by deletion strain varied in different growth phases in the presence of other antibiotics. Rsh also was involved in persister cells formation during rifampicin treatment under certain stress conditions, including acidic conditions, exposure to PBS, and heat stress. Moreover, Rsh impacted persister cell levels during rifampicin or enrofloxacin treatment in RAW264.7 macrophages. Certain typeIItoxin-antitoxin modules were upregulated under various stress conditions in B. abortus. We established that Rsh positively regulated the type II toxin-antitoxin mbcTA. Moreover, rifampicin-tolerant persister cells formation was elevated and ATP levels were decreased when mbcTA promoter was overexpressed in Rsh deletion background in stationary phase. Our results establish that (p)ppGpp synthetase Rsh plays a key role in B. abortus persistence and may serve as a potent novel target in combination with rifampicin in the development of new therapeutic approaches and prevention strategies to treat chronic infections of Brucella.

7.
J Clin Ultrasound ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38895932

RESUMEN

Pseudoaneurysm of the mitral-aortic intervalvular fibrosa is rare, particularly in children, and is potentially fatal. This article presents two cases of pediatric mitral-aortic intervalvular fibrosa pseudoaneurysm: one secondary to infective endocarditis and the other confirmed to be congenital in nature. The characteristic echocardiographic manifestations of mitral-aortic intervalvular fibrosa pseudoaneurysm demonstrated in this study will enhance diagnostic efficacy and guide early clinical intervention.

8.
Talanta ; 276: 126257, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38781913

RESUMEN

Alkyl imidazolium ionic liquids (Cn[MIM]), initially heralded as eco-friendly green solvents for diverse industrial applications, have increasingly been recognized fortheir biodegradability challenges and multiple biotoxicity. Despite potential health risks, research into the effects of Cn[MIM] on human health remains scarce, particularly regarding their detection in biological serum samples. This study validated a matrix-matched calibration quantitative method that utilizes solid-phase extraction (SPE) coupled with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The method was used to analyze the presence of 10 ionic liquids (ILs) with varying alkyl carbon chain lengths (C2-C12) across 300 human serum samples. Efficient separation was achieved using optimized SPE conditions and a BEH C18 column with an appropriate mobile phase. Results demonstrated a strong linear relationship (0.05-100 ng/mL; R2 = 0.995-0.999), with detection and quantification limits with detection and quantification limits ranging from 0.001 to 0.107 ng/mL and 0.003-0.355 ng/mL, respectively. Intraday and inter-day precisions were 0.85-6.99 % and 1.50-7.46 %, with recoveries between 82 and 113 %. The validated method detected C6MIM in 19 % of samples and C8MIM in 8.3 % of samples, with concentrations ranging from 0.02 to 111.70 µg/L and 0.09-16.99 µg/L, respectively, suggesting a potential risk of human exposure. This underscores the importance of robust detection methods in monitoring environmental and human health impacts of alkyl imidazolium compounds.


Asunto(s)
Imidazoles , Líquidos Iónicos , Espectrometría de Masas en Tándem , Humanos , Líquidos Iónicos/química , Espectrometría de Masas en Tándem/métodos , Imidazoles/química , Imidazoles/sangre , Monitoreo Biológico/métodos , Cromatografía Líquida de Alta Presión/métodos , Exposición a Riesgos Ambientales/análisis , Extracción en Fase Sólida , Límite de Detección
9.
Food Chem ; 451: 139469, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38703727

RESUMEN

Excipient selection is crucial to address the oxidation and solubility challenges of bioactive substances, impacting their safety and efficacy. AKPL, a novel ω-3 polyunsaturated fatty acids (PUFAs) esterified phospholipid derived from Antarctic krill, demonstrates unique antioxidant capabilities and synergistic effects. It exhibits pronounced surface activity and electronegativity at physiological pH, as evidenced by a critical micelle concentration (CMC) of 0.15 g/L and ζ-potential of -49.9 mV. In aqueous environments, AKPL self-assembles into liposomal structures, offering high biocompatibility and promoting cell proliferation. Its polyunsaturated bond-rich structure provides additional oxidation sites, imparting antioxidant properties superior to other phospholipids like DSPC and DOPC. Additionally, AKPL augments the efficacy of lipophilic antioxidants, such as alpha-tocopherol and curcumin, in aqueous media through both intermolecular and intramolecular interactions. In sum, AKPL emerges as an innovative unsaturated phospholipid, offering new strategies for encapsulating and delivering oxygen-sensitive agents.


Asunto(s)
Antioxidantes , Euphausiacea , Fosfolípidos , Euphausiacea/química , Animales , Fosfolípidos/química , Antioxidantes/química , Antioxidantes/farmacología , Coloides/química , Humanos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Regiones Antárticas , Ácidos Grasos Omega-3/química , Ácidos Grasos Omega-3/farmacología
10.
PLoS One ; 19(5): e0302651, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38743758

RESUMEN

Since the COVID-19, cough sounds have been widely used for screening purposes. Intelligent analysis techniques have proven to be effective in detecting respiratory diseases. In 2021, there were up to 10 million TB-infected patients worldwide, with an annual growth rate of 4.5%. Most of the patients were from economically underdeveloped regions and countries. The PPD test, a common screening method in the community, has a sensitivity of as low as 77%. Although IGRA and Xpert MTB/RIF offer high specificity and sensitivity, their cost makes them less accessible. In this study, we proposed a feature fusion model-based cough sound classification method for primary TB screening in communities. Data were collected from hospitals using smart phones, including 230 cough sounds from 70 patients with TB and 226 cough sounds from 74 healthy subjects. We employed Bi-LSTM and Bi-GRU recurrent neural networks to analyze five traditional feature sets including the Mel frequency cepstrum coefficient (MFCC), zero-crossing rate (ZCR), short-time energy, root mean square, and chroma_cens. The incorporation of features extracted from the speech spectrogram by 2D convolution training into the Bi-LSTM model enhanced the classification results. With traditional futures, the best TB patient detection result was achieved with the Bi-LSTM model, with 93.99% accuracy, 93.93% specificity, and 92.39% sensitivity. When combined with a speech spectrogram, the classification results showed 96.33% accuracy, 94.99% specificity, and 98.13% sensitivity. Our findings underscore that traditional features and deep features have good complementarity when fused using Bi LSTM modelling, which outperforms existing PPD detection methods in terms of both efficiency and accuracy.


Asunto(s)
Tos , Redes Neurales de la Computación , Tuberculosis Pulmonar , Humanos , Tos/diagnóstico , Tuberculosis Pulmonar/diagnóstico , Masculino , Femenino , Adulto , Persona de Mediana Edad , COVID-19/diagnóstico , Anciano , Sensibilidad y Especificidad
11.
Int Immunopharmacol ; 133: 112119, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38648715

RESUMEN

The bacterial flagellum is an elongated filament that protrudes from the cell and is responsible for bacterial motility. It can also be a pathogen-associated molecular pattern (PAMP) that regulates the host immune response and is involved in bacterial pathogenicity. In contrast to motile bacteria, the Brucella flagellum does not serve a motile purpose. Instead, it plays a role in regulating Brucella virulence and the host's immune response, similar to other non-motile bacteria. The flagellin protein, FliK, plays a key role in assembly of the flagellum and also as a potential virulence factor involved in the regulation of bacterial virulence and pathogenicity. In this study, we generated a Brucella suis S2 flik gene deletion strain and its complemented strain and found that deletion of the flik gene has no significant effect on the main biological properties of Brucella, but significantly enhanced the inflammatory response induced by Brucella infection of RAW264.7 macrophages. Further experiments demonstrated that the FliK protein was able to inhibit LPS-induced cellular inflammatory responses by down-regulating the expression of MyD88 and NF-κB, and by decreasing p65 phosphorylation in the NF-κB pathway; it also inhibited the expression of NLRP3 and caspase-1 in the NLRP3 inflammasome pathway. In conclusion, our study suggests that Brucella FliK may act as a virulence factor involved in the regulation of Brucella pathogenicity and modulation of the host immune response.


Asunto(s)
Brucelosis , Flagelina , Macrófagos , Factores de Virulencia , Animales , Ratones , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Brucella suis/patogenicidad , Brucella suis/inmunología , Brucelosis/inmunología , Brucelosis/microbiología , Caspasa 1/metabolismo , Flagelina/metabolismo , Inflamasomas/metabolismo , Inflamasomas/inmunología , Inflamación/inmunología , Lipopolisacáridos/inmunología , Macrófagos/inmunología , Macrófagos/microbiología , Factor 88 de Diferenciación Mieloide/metabolismo , Factor 88 de Diferenciación Mieloide/genética , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Células RAW 264.7 , Virulencia , Factores de Virulencia/metabolismo , Factores de Virulencia/genética
13.
J Soc Work End Life Palliat Care ; 20(2): 201-216, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38557360

RESUMEN

Racial disparities in hospice use are a longstanding concern in the U.S. Asian Americans are among the least likely to receive hospice care and to be included in studies on this topic. This study examined the knowledge, attitudes, and preferences related to hospice care among older Chinese immigrants and associated factors. A sample of 262 Chinese immigrants age 60+ was recruited from six older adult centers in NYC. In-person interviews were conducted in Mandarin and Cantonese. Non-English-speaking older Chinese immigrants had very limited knowledge about hospice care. Only 26% of respondents had heard of hospice, and a few could correctly define any components. After receiving a comprehensive definition of hospice care, study participants expressed a positive attitude and a strong willingness to use hospice if near the end of life. Notably, some respondents still held misconceptions about hospice and were less positive in their attitude and preference for hospice care. These findings underscore the necessity for clear and accessible information about hospice among this population throughout the trajectory from good health to end of life. Further research is needed to identify the range of factors that influence the attitudes and preferences of older Chinese immigrants toward hospice care.


Asunto(s)
Asiático , Emigrantes e Inmigrantes , Conocimientos, Actitudes y Práctica en Salud , Cuidados Paliativos al Final de la Vida , Humanos , Femenino , Masculino , Anciano , Emigrantes e Inmigrantes/psicología , Emigrantes e Inmigrantes/estadística & datos numéricos , Cuidados Paliativos al Final de la Vida/psicología , Conocimientos, Actitudes y Práctica en Salud/etnología , Asiático/psicología , Asiático/estadística & datos numéricos , Persona de Mediana Edad , Estados Unidos , Anciano de 80 o más Años , China/etnología , Prioridad del Paciente/etnología , Factores Socioeconómicos , Entrevistas como Asunto , Ciudad de Nueva York , Pueblos del Este de Asia
14.
Opt Express ; 32(4): 5397-5409, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439267

RESUMEN

Active-polarization imaging holds significant promise for achieving clear underwater vision. However, only static targets were considered in previous studies, and a background region was required for image restoration. To address these issues, this study proposes an underwater dynamic polarization imaging method based on image pyramid decomposition and reconstruction. During the decomposition process, the polarized image is downsampled to generate an image pyramid. Subsequently, the spatial distribution of the polarization characteristics of the backscattered light is reconstructed by upsampling, which recovered the clear scene. The proposed method avoids dependence on the background region and is suitable for moving targets with varying polarization properties. The experimental results demonstrate effective elimination of backscattered light while sufficiently preserving the target details. In particular, for dynamic targets, processing times that fulfill practical requirements and yield superior recovery effects are simultaneously obtained.

15.
ChemSusChem ; 17(10): e202301567, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38517635

RESUMEN

The direct synthesis of cyclic carbonates through oxidative carboxylation of alkenes using CO2 and O2 offers a sustainable and carbon-neutral method for CO2 utilization, which is, however, still a largely unexplored field. Here we develop a single-atom catalyst (SAC) Co-N/O-C as the earth-abundant metal catalyst for the oxidative carboxylation of styrene with CO2 and O2. Remarkably, even using the flue gas as an impure CO2 and O2 source, desired cyclic carbonate could be obtained with moderate productivity, which shows the potential for integrated CO2 capture and conversion, leveraging the high CO2 adsorption capacity of Co-N/O-C. In addition, the catalyst can be reused five times without an obvious decline in activity. Detailed characterizations and theoretical calculations elucidate the crucial role of single Co atoms in activating O2 and CO2, as well as controlling selectivity.

16.
ACS Appl Mater Interfaces ; 16(14): 17870-17880, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38537160

RESUMEN

Silicon (Si) is considered as the most likely choice for the high-capacity lithium-ion batteries owing to its ultrahigh theoretical capacity (4200 mA h g-1) being over 10 times than that of traditional graphite anode materials (372 mA h g-1). However, its widespread application is limited by problems such as a large volume expansion and low electrical conductivity. Herein, we design a hollow nitrogen-doped carbon-coated silicon (Si@Co-HNC) composite in a water-based system via a synergistic protecting-etching strategy of tannic acid. The prepared Si@Co-HNC composite can effectively mitigate the volume change of silicon and improve the electrical conductivity. Moreover, the abundant voids inside the carbon layer and the porous carbon layer accelerate the transport of electrons and lithium ions, resulting in excellent electrochemical performance. The reversible discharge capacity of 1205 mA h g-1 can be retained after 120 cycles at a current density of 0.5 A g-1. In particular, the discharge capacity can be maintained at 1066 mA h g-1 after 300 cycles at a high current density of 1 A g-1. This study provides a new strategy for the design of Si-based anode materials with excellent electrical conductivity and structural stability.

17.
Adv Sci (Weinh) ; 11(18): e2401868, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460160

RESUMEN

Metal-organic frameworks (MOFs) are promising candidates for room-temperature hydrogen storage materials after modification, thanks to their ability to chemisorb hydrogen. However, the hydrogen adsorption strength of these modified MOFs remains insufficient to meet the capacity and safety requirements of hydrogen storage systems. To address this challenge, a highly defective framework material known as de-MgMOF is prepared by gently annealing Mg-MOF-74. This material retains some of the crystal properties of the original Mg-MOF-74 and exhibits exceptional hydrogen storage capacity at above-ambient temperatures. The MgO5 knots around linker vacancies in de-MgMOF can adsorb a significant amount of dissociated and nondissociated hydrogen, with adsorption enthalpies ranging from -22.7 to -43.6 kJ mol-1, indicating a strong chemisorption interaction. By leveraging a spillover catalyst of Pt, the material achieves a reversible hydrogen storage capacity of 2.55 wt.% at 160 °C and 81 bar. Additionally, this material offers rapid hydrogen uptake/release, stable cycling, and convenient storage capabilities. A comprehensive techno-economic analysis demonstrates that this material outperforms many other hydrogen storage materials at the system level for on-board applications.

18.
J Am Chem Soc ; 146(9): 6037-6044, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38377954

RESUMEN

Alkene hydroformylation is one of the largest industrial reactions on an industrial scale; however, the development of nonnoble heterogeneous catalysts is usually limited by their low activities and stabilities. Herein, we constructed a 1% Co2C/SiO2 catalyst featuring Co-Cvacancy-Co-C symmetry-breaking sites, which generated a polar surface exhibiting a moderate charge density gradient at the localized Co atoms. Comparatively, this catalyst exhibited notable enhancements in the adsorption and activation of the reactants, as well as in the polarity between intermediates. Significantly, the spatial distance between the adsorption sites of intermediates was reduced, thereby effectively decreasing the energy barrier of reaction processes. As the density of the symmetry-breaking sites increased, the turnover number for propene hydroformylation soared to 18 363, exceeding the activity of heterogeneous Co-based catalysts reported thus far by 1 or 2 orders of magnitude, and the catalyst exhibited high stability during the reaction. This study provides a methodology for constructing atomically active sites, which holds great potential for the design and development of highly efficient catalysts.

19.
Se Pu ; 42(2): 211-216, 2024 Feb.
Artículo en Chino | MEDLINE | ID: mdl-38374602

RESUMEN

The purposes of this study are to explore the contamination levels of perfluorinated and polyfluoroalkyl substances (PFASs) in breast milk and assess their exposure risk to infants. Based on data from a birth cohort study conducted in Yingcheng, Hubei Province, from 2018 to 2021, the contents of 23 types of PFASs in the breast milk of 324 pregnant women were determined using isotope dilution-high performance liquid chromatography-tandem mass spectrometry. Multiple linear regression was then performed to analyze the effects of various demographic characteristics and eating habits on the concentration of PFASs in breast milk. The daily PFASs intake of infants through breast milk was estimated, and the exposure risk of infants was also assessed. The results revealed that 23 types of PFASs in breast milk had good linear relationships in the range of 0.2-100 ng/mL, with correlation coefficients greater than 0.992. The limits of detection were 5-42 pg/mL, the limits of quantification were 15-126 pg/mL, the recoveries were 65.6%-108.1%, and the relative standard deviations were 1.6%-12.8%. Perfluorooctane sulfonic acid (PFOS), perfluorooctanoate acid (PFOA), and perfluorohexanesulfonic acid (PFHxS), with median concentrations of 200.7, 63.5, and 25.2 pg/mL, respectively, were the main PFASs found in breast milk. The detection rates of these three contaminants were higher than 80%, whereas the detection rates of other compounds were lower than 45%. The results of multiple linear regression showed that older pregnant women and a higher frequency of pickled food intake may be related to increased PFAS levels in breast milk whereas a higher frequency of legume intake may be related to decreased PFAS levels in breast milk. The median estimated daily intakes (EDIs) of PFOS, PFOA, and PFHxS for infants were 25.1, 7.9, and 3.2 ng/(kg·d), respectively. In summary, this study found notable PFAS levels in breast milk in Yingcheng, Hubei Province. Among these PFASs, PFOS, PFOA, and PFHxS were the main contaminants. Maternal age as well as pickled food and legume intake may affect the PFAS level in breast milk. The health risk of PFAS intake through breast milk to some infants is worthy of attention and further study.


Asunto(s)
Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Ácidos Sulfónicos , Lactante , Humanos , Femenino , Embarazo , Leche Humana/química , Estudios de Cohortes , Caprilatos/análisis , Fluorocarburos/análisis , Verduras , Contaminantes Ambientales/análisis
20.
Discov Oncol ; 15(1): 45, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383815

RESUMEN

OBJECTIVE: Our current study aimed to assess the relationship between TNF-related apoptosis-inducing ligand (TRAIL) and ferroptosis in non-small cell lung cancer (NSCLC) development. METHODS: The expression of TRAIL was detected by western blot, RT-qRCR and immunohistochemistry. The viability of NSCLC cells was analyzed by CCK-8 kit. The migration and invasion of NSCLC cells were detected by wound healing assay and transwell assay, respectively. Labile iron pool (LIP) was detected based on the calcein-acetoxymethyl ester method. Ferrous iron (Fe2+) and iron levels were assessed by detection kits. The levels of superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) were measured using corresponding detection kits. Mice tumor xenograft models were used for the in vivo research. RESULTS: The expression of TRAIL was reduced in H1299, NCL-H1395, and A549 cells compared with BEAS-2B cells. The up-regulation of TRAIL expression significantly reduced cell viability, invasion, and migration of H1299 and A549 cells. TRAIL reduced the expression of ferroptosis-related genes (FTH1, GPX4, and SLC7A11), increased the levels of LIP, iron, and Fe2+, and promoted lipid peroxidation, thereby predisposing NSCLC cells to ferroptosis. TRAIL up-regulated the expression of phosphate modification of ASK-1 and JNK. ASKI-1 inhibitor GS-4977 attenuated the effects of TRAIL on the viability, migration, invasion, and ferroptosis of H1299 cells. Furthermore, TRAIL further suppressed tumor growth and ferroptosis in mice tumor xenograft models. CONCLUSION: We indicated that overexpression of TRAIL induced ferroptosis in NSCLC cells and exerted anti-tumor effects. Mechanistically, TRAIL promoted ferroptosis by the activation of the ASK-1/JNK1 pathway. Our results may provide new therapeutic strategies for NSCLC.

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