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1.
Chemosphere ; 367: 143542, 2024 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-39424159

RESUMEN

The electrochemical treatment of saline wastewater is prone to the formation of inorganic chlorinated byproducts, being a significant challenge for this technology. In this study, we introduce an electrooxidation system utilizing a self-supporting nitrogen-doped carbon-based cathode embedded in carbon cloth (N@C-CC), designed to generate H2O2. This system aims to rapidly neutralize free chlorine produced at the anode, a precursor to inorganic chlorinated byproducts, thereby reducing their formation. Our results demonstrate that using the N@C-CC cathode in saline wastewater treatment yielded considerably lower concentrations of ClO3⁻ and ClO4⁻ (0.08 mM and 0.024 mM, respectively), which were only 20.5% and 22.7% of the levels produced using a Pt cathode without H2O2 generation. Moreover, the presence of cathodically generated H2O2 that quenches free chlorine did not significantly impact the degradation performance of phenol. Electron paramagnetic resonance tests and quenching experiments indicated that 1O2 was primarily responsible for phenol removal. Validation with real wastewater demonstrated reductions of 68.6% and 56.3% in ClO3- and ClO4- concentrations, respectively, while effectively removing other pollutants. This study thus offers a compelling method for mitigating the formation of inorganic chlorinated byproducts during the electrooxidation of saline wastewater.

2.
Environ Sci Technol ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39271452

RESUMEN

Acid mine drainage (AMD) raises a global environmental concern impacting the iron cycle. Although the formation of Fe(III) minerals in AMD-impacted waters has previously been reported to be regulated by biological processes, the role of abiotic processes remains largely unknown. This study first reported that a photochemical reaction coupled with O2 significantly accelerated the formation of Fe(III) flocculates (i.e., schwertmannite) in the AMD, as evidenced by the comparison of samples from contaminated sites across different natural conditions at latitudes 24-29° N. Combined with experimental and modeling results, it is further discovered that the intramolecular oxidation of photogenerated Fe(II) with a five-coordinative pyramidal configuration (i.e., [(H2O)5Fe]2+) by O2 was the key in enhancing the photooxidation of Fe(II) in the simulated AMD. The in situ attenuated total reflectance-Fourier transform infrared spectrometry (ATR-FTIR), UV-vis spectroscopy, solvent substitution, and quantum yield analyses indicated that, acting as a precursor for flocculation, [(H2O)5Fe]2+ likely originated from both the dissolved and colloidal forms of Fe(III) through homogeneous and surface ligand-to-metal charge transfers. Density functional theory calculations and X-ray absorption spectroscopy results further suggested that the specific oxidation pathways of Fe(II) produced the highly reactive iron species and triggered the hydrolysis and formation of transient dihydroxo dimers. The proposed new pathways of Fe cycle are crucial in controlling the mobility of heavy metal anions in acidic waters and enhance the understanding of complicated iron biochemistry that is related to the fate of contaminants and nutrients.

3.
Biol Sex Differ ; 15(1): 68, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39223676

RESUMEN

BACKGROUND: Differences of sex development (DSD) are congenital conditions in which chromosomal, gonadal, or phenotypic sex is atypical. In more than 50% of human DSD cases, a molecular diagnosis is not available. In intensively farmed pig populations, the incidence of XX DSD pigs is relatively high, leading to economic losses for pig breeders. Interestingly, in the majority of 38, XX DSD pigs, gonads still develop into testis-like structures or ovotestes despite the absence of the testis-determining gene (SRY). However, the current understanding of the molecular background of XX DSD pigs remains limited. METHODS: Anatomical and histological characteristics of XX DSD pigs were analysed using necropsy and HE staining. We employed whole-genome sequencing (WGS) with 10× Genomics technology and used de novo assembly methodology to study normal female and XX DSD pigs. Finally, the identified variants were validated in 32 XX DSD pigs, and the expression levels of the candidate variants in the gonads of XX DSD pigs were further examined. RESULTS: XX DSD pigs are characterised by the intersex reproductive organs and the absence of germ cells in the seminiferous tubules of the gonads. We identified 4,950 single-nucleotide polymorphisms (SNPs) from non-synonymous mutations in XX DSD pigs. Cohort validation results highlighted two specific SNPs, "c.218T > C" in the "Interferon-induced transmembrane protein 1 gene (IFITM1)" and "c.1043C > G" in the "Newborn ovary homeobox gene (NOBOX)", which were found exclusively in XX DSD pigs. Moreover, we verified 14 candidate structural variants (SVs) from 1,474 SVs, identifying a 70 bp deletion fragment in intron 5 of the WW domain-containing oxidoreductase gene (WWOX) in 62.5% of XX DSD pigs. The expression levels of these three candidate genes in the gonads of XX DSD pigs were significantly different from those of normal female pigs. CONCLUSION: The nucleotide changes of IFITM1 (c.218T > C), NOBOX (c.1043 C > G), and a 70 bp deletion fragment of the WWOX were the most dominant variants among XX DSD pigs. This study provides a theoretical basis for better understanding the molecular background of XX DSD pigs. DSD are conditions affecting development of the gonads or genitalia. These disorders can happen in many different types of animals, including pigs, goats, dogs, and people. In people, DSD happens in about 0.02-0.13% of births, and in pigs, the rate is between 0.08% and 0.75%. Pigs have a common type of DSD where the animal has female chromosomes (38, XX) but no SRY gene, which is usually found on the Y chromosome in males. XX DSD pigs may look like both males and females on the outside and have testis-like or ovotestis (a mix of ovary and testis) gonads inside. XX DSD pigs often lead to not being able to have piglets, slower growth, lower chance of survival, and poorer meat quality. Here, we used a method called whole-genome de novo sequencing to look for variants in the DNA of XX DSD pigs. We then checked these differences in a larger group of pigs. Our results reveal the nucleotide changes in IFITM1 (c.218T > C), NOBOX (c.1043 C > G), and a 70 bp deletion fragment in intron 5 of the WWOX, all linked to XX DSD pigs. The expression levels of these three genes were also different in the gonads of XX DSD pigs compared to normal female pigs. These variants are expected to serve as valuable molecular markers for XX DSD pigs. Because pigs are a lot like humans in their genes, physiology, and body structure, this research could help us learn more about what causes DSD in people.


Asunto(s)
Trastornos del Desarrollo Sexual , Animales , Femenino , Masculino , Porcinos/genética , Trastornos del Desarrollo Sexual/genética , Secuenciación Completa del Genoma , Desarrollo Sexual/genética , Polimorfismo de Nucleótido Simple , Testículo/metabolismo
4.
Environ Sci Technol ; 58(33): 14949-14960, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39126387

RESUMEN

The presence and induced secondary reactions of natural organic matter (NOM) significantly affect the remediation efficacy of in situ chemical oxidation (ISCO) systems. However, it remains unclear how this process relates to organic radicals generated from reactions between the NOM and oxidants. The study, for the first time, reported the vital roles and transformation pathways of carbon-centered radicals (CCR•) derived from NOM in activated persulfate (PS) systems. Results showed that both typical terrestrial/aquatic NOM isolates and collected NOM samples produced CCR• by scavenging activated PS and greatly enhanced the dehalogenation performance under anoxic conditions. Under oxic conditions, newly formed CCR• could be oxidized by O2 and generate organic peroxide intermediates (ROO•) to catalytically yield additional •OH without the involvement of PS. Nuclear magnetic resonance (NMR) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) results indicated that CCR• predominantly formed from carboxyl and aliphatic structures instead of aromatics within NOM through hydrogen abstraction and decarboxylation reactions by SO4•- or •OH. Specific anoxic reactions (i.e., dehalogenation and intramolecular cross-coupling reactions) further promoted the transformation of CCR• to more unsaturated and polymerized/condensed compounds. In contrast, oxic propagation of ROO• enhanced bond breakage/ring cleavage and degradation of CCR• due to the presence of additional •OH and self-decomposition. This study provides novel insights into the role of NOM and O2 in ISCO and the development of engineered strategies for creating organic radicals capable of enhancing the remediation of specific contaminants and recovering organic carbon.


Asunto(s)
Carbono , Carbono/química , Oxidación-Reducción , Sulfatos/química
5.
Schizophr Res ; 271: 292-299, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39079406

RESUMEN

BACKGROUND: Thalamic abnormalities in schizophrenia are recognized, alongside cognitive deficits. However, the current findings about these abnormalities during the prodromal period remain relatively few and inconsistent. This study applied multimodal methods to explore the alterations in thalamic function and structure and their relationship with cognitive function in first-episode schizophrenia (FES) patients and ultra-high-risk (UHR) individuals, aiming to affirm the thalamus's role in schizophrenia development and cognitive deficits. METHODS: 75 FES patients, 60 UHR individuals, and 60 healthy controls (HC) were recruited. Among the three groups, gray matter volume (GMV) and functional connectivity (FC) were evaluated to reflect the structural and functional abnormalities in the thalamus. Pearson correlation was used to calculate the association between these abnormalities and cognitive impairments. RESULTS: No significant difference in GMV of the thalamus was found among the abovementioned three groups. Compared with HC individuals, FES patients had decreased thalamocortical FC mostly in the thalamocortical triple network, including the default mode network (DMN), salience network (SN), and executive control network (ECN). UHR individuals had similar but milder dysconnectivity as the FES group. Furthermore, FC between the left thalamus and right putamen was significantly correlated with execution speed and attention in the FES group. CONCLUSIONS: Our findings revealed decreased thalamocortical FC associated with cognitive deficits in FES and UHR subjects. This improves our understanding of the functional alterations in thalamus in prodromal stage of schizophrenia and the related factors of the cognitive impairment of the disease. TRIAL REGISTRATION: ClinicalTrials.govNCT03965598; https://clinicaltrials.gov/ct2/show/NCT03965598.


Asunto(s)
Disfunción Cognitiva , Imagen por Resonancia Magnética , Esquizofrenia , Tálamo , Humanos , Esquizofrenia/fisiopatología , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/patología , Tálamo/diagnóstico por imagen , Tálamo/fisiopatología , Tálamo/patología , Masculino , Femenino , Adulto Joven , Adulto , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Sustancia Gris/fisiopatología , Conectoma , Adolescente , Síntomas Prodrómicos , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/fisiopatología , Corteza Cerebral/patología , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Red Nerviosa/patología , Red en Modo Predeterminado/fisiopatología , Red en Modo Predeterminado/diagnóstico por imagen , Red en Modo Predeterminado/patología , Función Ejecutiva/fisiología
6.
Water Res ; 261: 122068, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39003879

RESUMEN

Electrochemical advanced oxidation processes (EAOPs) have shown great promise for treating industrial wastewater contaminated with phenolic compounds. However, the presence of chloride in the wastewater leads to the production of undesirable chlorinated organic and inorganic byproducts, limiting the application of EAOPs. To address this challenge, we investigated the potential of incorporating Fe(II) and Fe(III) into the EAOPs with a boron-doped diamond (BDD) anode under near-neutral conditions. Our findings revealed that both Fe(II) and Fe(III) facilitated the generation of high-valent iron-oxo species (Fe(IV) and Fe(V)) in the anodic compartment, thereby reducing the oxidation contribution of reactive chlorine species. Remarkably, the addition of 1000 µM Fe(II) under high chloride conditions resulted in over a 2.8-fold increase in the oxidation rate of 50 µM phenolic contaminants at pH 6.5. Furthermore, 1000 µM Fe(II) contributed to a reduction of more than 66% in the formation of chlorinated byproducts, consequently enhancing the biodegradability of the treated water. Additionally, transitioning from batch mode to continuous flow mode further amplified the positive effects of Fe(II) on the EAOPs. Overall, this study presents a modified electrochemical approach that simultaneously enhanced the degradation of phenolic contaminants and improved the biodegradability of wastewater with high chloride concentrations.


Asunto(s)
Cloruros , Técnicas Electroquímicas , Hierro , Oxidación-Reducción , Fenoles , Aguas Residuales , Contaminantes Químicos del Agua , Aguas Residuales/química , Fenoles/química , Cloruros/química , Hierro/química , Contaminantes Químicos del Agua/química , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Electrodos , Boro/química
7.
J Clin Med ; 13(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38930152

RESUMEN

Background/Objectives: Dyslipidemia is a well-established risk factor for cardiovascular disease (CVD). However, among available drug treatments, only those targeted at lowering LDL-C and consequently TC have demonstrated efficacy in preventing CVD. This is to say that the benefit for those with isolated high TG or low HDL-C is limited. The objective of this study is to examine the overlapping pattern of the four dyslipidemia components in US adult populations, which is important for quantifying the proportion of those who are less likely to benefit from lipid-lowering drugs and for a more precise use of the drug. Methods: A total of 7822 participants aged over 20 with abnormalities in any of the four lipid parameters, excluding those on lipid-lowering medications, were included from the National Health and Nutrition Examination Survey (NHANES) cycles spanning 1999-2000 through 2017-2018. The proportions of different combinations of them were calculated and presented using area-proportional Euler plots. Results: High TC, high LDL-C, high TG, and low HDL-C were seen in 32.8% (95% CI: 31.3%-34.2%), 28.1% (95% CI: 26.6%-29.6%), 26.7% (95% CI: 25.4%-28.0%), and 65.9% (95% CI: 64.0%-67.7%) of the people with dyslipidemia, respectively. The proportions of dyslipidemia cases attributable to "high LDL-C or high TC" (irrespective of HDL-C and TG levels), "normal LDL-C, normal TC, but high TG" (irrespective of HDL-C level), and "normal LDL-C, normal TC, normal TG, but low HDL-C" (i.e., isolated low HDL-C) accounted for 37.5% (95% CI: 35.9%-39.1%), 18.3% (95% CI: 17.2%-19.4%), and 44.2% (95% CI: 42.5%-46.0%), respectively. Conclusions: Some two-thirds of those with dyslipidemia had low HDL-C or high TG but normal LDL-C and normal TC. As these people are less likely to benefit from currently available drug treatments in terms of CVD prevention, it is important to identify other effective strategies or interventions targeted at them in order to achieve more precise and cost-effective management of dyslipidemia.

8.
Cereb Cortex ; 34(6)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38897816

RESUMEN

Brain structural abnormality has been observed in the prodromal and early stages of schizophrenia, but the mechanism behind it is not clear. In this study, to explore the association between cortical abnormalities, metabolite levels, inflammation levels and clinical symptoms of schizophrenia, 51 drug-naive first-episode schizophrenia (FES) patients, 51 ultra-high risk for psychosis (UHR), and 51 healthy controls (HC) were recruited. We estimated gray matter volume (GMV), cortical thickness (CT), concentrations of different metabolites, and inflammatory marks among four groups (UHR converted to psychosis [UHR-C], UHR unconverted to psychosis [UHR-NC], FES, HC). UHR-C group had more CT in the right lateral occipital cortex and the right medial orbito-frontal cortex (rMOF), while a significant reduction in CT of the right fusiform cortex was observed in FES group. UHR-C group had significantly higher concentration of IL-6, while IL-17 could significantly predict CT of the right fusiform and IL-4 and IL-17 were significant predictors of CT in the rMOF. To conclude, it is reasonable to speculate that the increased CT in UHR-C group is related to the inflammatory response, and may participate in some compensatory mechanism, but might become exhaustive with the progress of the disease due to potential neurotoxic effects.


Asunto(s)
Corteza Cerebral , Imagen por Resonancia Magnética , Esquizofrenia , Humanos , Esquizofrenia/patología , Esquizofrenia/diagnóstico por imagen , Masculino , Femenino , Adulto Joven , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Adulto , Sustancia Gris/patología , Sustancia Gris/diagnóstico por imagen , Adolescente
9.
Environ Sci Technol ; 58(27): 12212-12224, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38916044

RESUMEN

The electrochemical technology provides a practical and viable solution to the global water scarcity issue, but it has an inherent challenge of generating toxic halogenated byproducts in treatment of saline wastewater. Our study reveals an unexpected discovery: the presence of a trace amount of Br- not only enhanced the electrochemical oxidation of organic compounds with electron-rich groups but also significantly reduced the formation of halogenated byproducts. For example, in the presence of 20 µM Br-, the oxidation rate of phenol increased from 0.156 to 0.563 min-1, and the concentration of total organic halogen decreased from 59.2 to 8.6 µM. Through probe experiments, direct electron transfer and HO• were ruled out as major contributors; transient absorption spectroscopy (TAS) and computational kinetic models revealed that trace Br- triggers a shift in the dominant reactive species from Cl2•- to Br2•-, which plays a key role in pollutant removal. Both TAS and electron paramagnetic resonance identified signals unique to the phenoxyl and carbon-centered radicals in the Br2•--dominated system, indicating distinct reaction mechanisms compared to those involving Cl2•-. Kinetic isotope experiments and density functional theory calculations confirmed that the interaction between Br2•- and phenolic pollutants follows a hydrogen atom abstraction pathway, whereas Cl2•- predominantly engages pollutants through radical adduct formation. These insights significantly enhance our understanding of bromine radical-involved oxidation processes and have crucial implications for optimizing electrochemical treatment systems for saline wastewater.


Asunto(s)
Aguas Residuales , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Oxidación-Reducción , Halogenación , Técnicas Electroquímicas , Cinética , Purificación del Agua/métodos
10.
Gait Posture ; 111: 143-149, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703442

RESUMEN

BACKGROUND: Obesity can cause structural changes and functional adjustments in growing children's feet. However, there is a lack of continuous observation of changes in feet in children with persistent obesity during important developmental periods. This makes it challenging to provide precise preventive measures. OBJECTIVE: This study aimed to investigate the effects of persistent obesity on gait patterns in children at an important stage in the formation of a robust foot arch. METHODS: The Footscan® plantar pressure system was used for 3 checks over two years. A total of 372 children aged 7-8 years participated in the study, and gait data from 33 children who maintained normal weight and 26 children with persistent obesity were finally selected. Repeated measures ANOVA or Friedman's test were used for longitudinal comparisons. Independent-Sample t-tests or the Mann-Whitney-Wilcoxon tests were used for cross-sectional comparisons. RESULTS: During the important period of development, children with persistent obesity did not exhibit a significant decrease in the arch index and had significantly higher values than the normal group in the third check. The persistently obese children showed increased load accumulation in the lateral rearfoot, first metatarsophalangeal joints, and the great toe regions. Children with persistent obesity had significantly greater medial-lateral displacements in the initial contact phase and forefoot contact phase than normal children in the first check. These differences diminished between the second and third checks. SIGNIFICANCE: Persistent obesity during an important period of foot development leads to slow or abnormal development of arch structure and affects foot loading patterns with heel inverted and forefoot everted. Additionally, the development of gait stability is not limited by persistent obesity.


Asunto(s)
Pie , Marcha , Humanos , Niño , Masculino , Femenino , Estudios Longitudinales , Marcha/fisiología , Pie/fisiopatología , Pie/fisiología , Fenómenos Biomecánicos , Obesidad Infantil/fisiopatología , Estudios Transversales
11.
Sci Rep ; 14(1): 1909, 2024 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-38253669

RESUMEN

The blood‒brain barrier (BBB) acts as a hindrance to drug therapy reaching the brain. With an increasing incidence of neurovascular diseases and brain cancer metastases, there is a need for an ideal in vitro model to develop novel methodologies for enhancing drug delivery to the brain. Here, we established a multicellular human brain spheroid model that mimics the BBB both architecturally and functionally. Within the spheroids, endothelial cells and pericytes localized to the periphery, while neurons, astrocytes, and microglia were distributed throughout. Ultrasound-targeted microbubble cavitation (UTMC) is a novel noninvasive technology for enhancing endothelial drug permeability. We utilized our three-dimensional (3D) model to study the feasibility and mechanisms regulating UTMC-induced hyperpermeability. UTMC caused a significant increase in the penetration of 10 kDa Texas red dextran (TRD) into the spheroids, 100 µm beyond the BBB, without compromising cell viability. This hyperpermeability was dependent on UTMC-induced calcium (Ca2+) influx and endothelial nitric oxide synthase (eNOS) activation. Our 3D brain spheroid model, with its intact and functional BBB, offers a valuable platform for studying the bioeffects of UTMC, including effects occurring spatially distant from the endothelial barrier.


Asunto(s)
Barrera Hematoencefálica , Neoplasias Encefálicas , Humanos , Preparaciones Farmacéuticas , Células Endoteliales , Encéfalo , Astrocitos
12.
Oncogene ; 43(11): 789-803, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38273024

RESUMEN

WEE1 and CHEK1 (CHK1) kinases are critical regulators of the G2/M cell cycle checkpoint and DNA damage response pathways. The WEE1 inhibitor AZD1775 and the CHK1 inhibitor SRA737 are in clinical trials for various cancers, but have not been thoroughly examined in prostate cancer, particularly castration-resistant (CRPC) and neuroendocrine prostate cancers (NEPC). Our data demonstrated elevated WEE1 and CHK1 expressions in CRPC and NEPC cell lines and patient samples. AZD1775 resulted in rapid and potent cell killing with comparable IC50s across different prostate cancer cell lines, while SRA737 displayed time-dependent progressive cell killing with 10- to 20-fold differences in IC50s. Notably, their combination synergistically reduced the viability of all CRPC cell lines and tumor spheroids in a concentration- and time-dependent manner. Importantly, in a transgenic mouse model of NEPC, both agents alone or in combination suppressed tumor growth, improved overall survival, and reduced the incidence of distant metastases, with SRA737 exhibiting remarkable single agent anticancer activity. Mechanistically, SRA737 synergized with AZD1775 by blocking AZD1775-induced feedback activation of CHK1 in prostate cancer cells, resulting in increased mitotic entry and accumulation of DNA damage. In summary, this preclinical study shows that CHK1 inhibitor SRA737 alone and its combination with AZD1775 offer potential effective treatments for CRPC and NEPC.


Asunto(s)
Proteínas de Ciclo Celular , Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Ratones , Animales , Proteínas de Ciclo Celular/genética , Proteínas Tirosina Quinasas/genética , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Proteínas Nucleares/metabolismo , Pirimidinonas/farmacología , Daño del ADN , Línea Celular Tumoral
13.
Environ Sci Technol ; 57(49): 20915-20928, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38016695

RESUMEN

Mixed metal oxide (MMO) anodes are commonly used for electrochlorination of ammonium (NH4+) in wastewater treatment, but they suffer from low efficiency due to inadequate chlorine generation at low Cl- concentrations and sluggish reaction kinetics between free chlorine and NH4+ under acidic pH conditions. To address this challenge, we develop a straightforward wet chemistry approach to synthesize BiOCl-functionalized MMO electrodes using the MMO as an efficient Ohmic contact for electron transfer. Our study demonstrates that the BiOCl@MMO anode outperforms the pristine MMO anode, exhibiting higher free chlorine generation (24.6-60.0 mg Cl2 L-1), increased Faradaic efficiency (75.5 vs 31.0%), and improved rate constant of NH4+ oxidation (2.41 vs 0.76 mg L-1 min-1) at 50 mM Cl- concentration. Characterization techniques including electron paramagnetic resonance and in situ transient absorption spectra confirm the production of chlorine radicals (Cl• and Cl2•-) by the BiOCl/MMO anode. Laser flash photolysis reveals significantly higher apparent second-order rate constants ((4.3-4.9) × 106 M-1 s-1 at pH 2.0-4.0) for the reaction between NH4+ and Cl•, compared to the undetectable reaction between NH4+ and Cl2•-, as well as the slower reaction between NH4+ and free chlorine (102 M-1 s-1 at pH < 4.0) within the same pH range, emphasizing the significance of Cl• in enhancing NH4+ oxidation. Mechanistic studies provide compelling evidence of the capacity of BiOCl for Cl- adsorption, facilitating chlorine evolution and Cl• generation. Importantly, the BiOCl@MMO anode exhibits excellent long-term stability and high catalytic activity for NH4+-N removal in a real landfill leachate. These findings offer valuable insights into the rational design of electrodes to improve electrocatalytic NH4+ abatement, which holds great promise for wastewater treatment applications.


Asunto(s)
Compuestos de Amonio , Contaminantes Químicos del Agua , Aguas Residuales , Cloro , Oxidación-Reducción , Óxidos/química , Electrodos , Contaminantes Químicos del Agua/análisis , Cloruros
14.
Res Sq ; 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37987002

RESUMEN

WEE1 and CHEK1 (CHK1) kinases are critical regulators of the G2/M cell cycle checkpoint and DNA damage response pathways. The WEE1 inhibitor AZD1775 and the CHK1 inhibitor SRA737 are in clinical trials for various cancers, but have not been examined in prostate cancer, particularly castration-resistant (CRPC) and neuroendocrine prostate cancers (NEPC). Our data demonstrated elevated WEE1 and CHK1 expressions in CRPC/NEPC cell lines and patient samples. AZD1775 resulted in rapid and potent cell killing with comparable IC50s across different prostate cancer cell lines, while SRA737 displayed time-dependent progressive cell killing with 10- to 20-fold differences in IC50s. Notably, their combination synergistically reduced the viability of all CRPC cell lines and tumor spheroids in a concentration- and time-dependent manner. Importantly, in a transgenic mouse model of NEPC, both agents alone or in combination suppressed tumor growth, improved overall survival, and reduced the incidence of distant metastases, with SRA737 exhibiting remarkable single agent anticancer activity. Mechanistically, SRA737 synergized with AZD1775 by blocking AZD1775-induced feedback activation of CHK1 in prostate cancer cells, resulting in increased mitotic entry and accumulation of DNA damage. In summary, this preclinical study shows that CHK1 inhibitor SRA737 alone and its combination with AZD1775 offer potential effective treatments for CRPC and NEPC.

15.
Psychiatry Res ; 322: 115123, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36827856

RESUMEN

Schizophrenia has been associated with abnormal intrinsic brain activity, involving various cognitive impairments. Qualitatively similar abnormalities are seen in individuals at ultra-high risk (UHR) for psychosis. In this study, resting-state fMRI (rs-fMRI) data were collected from 44 drug-naïve first-episode schizophrenia (Dn-FES) patients, 48 UHR individuals, and 40 healthy controls (HCs). The fractional amplitude of low-frequency fluctuations (fALFF), regional homogeneity (ReHo), and functional connectivity (FC), were performed to evaluate resting brain function. A support vector machine (SVM) was applied for classification analysis. Compared to HCs, both clinical groups showed increased fALFF in the central executive network (CEN), decreased ReHo in the ventral visual pathway (VVP) and decreased FC in temporal-sensorimotor regions. Excellent performance was achieved by using fALFF value in distinguishing both FES (sensitivity=83.21%, specificity=80.58%, accuracy=81.37%, p=0.009) and UHR (sensitivity=75.88%, specificity=85.72%, accuracy=80.72%, p<0.001) from HC group. Moreover, the study highlighted the importance of frontal and temporal alteration in the pathogenesis of schizophrenia. However, no fMRI features were observed that could well distinguish Dn-FES from UHR group. To conclude, fALFF in the CEN may provide potential power for identifying individuals at the early stage of schizophrenia and the alteration in the frontal and temporal lobe may be important to these individuals.


Asunto(s)
Trastornos Psicóticos , Esquizofrenia , Humanos , Encéfalo , Mapeo Encefálico , Lóbulo Temporal , Imagen por Resonancia Magnética
16.
Sci Rep ; 13(1): 1639, 2023 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-36717567

RESUMEN

The total synthesis of four novel mono-methoxy and hydroxyl substituted ring-A dihydronarciclasine derivatives enabled identification of the 7-hydroxyl derivative as a potent and selective antiviral agent targeting SARSCoV-2 and HSV-1. The concentration of this small molecule that inhibited HSV-1 infection by 50% (IC50), determined by using induced pluripotent stem cells (iPCS)-derived brain organ organoids generated from two iPCS lines, was estimated to be 0.504 µM and 0.209 µM. No significant reduction in organoid viability was observed at concentrations up to 50 mM. Genomic expression analyses revealed a significant effect on host-cell innate immunity, revealing activation of the integrated stress response via PERK kinase upregulation, phosphorylation of eukaryotic initiation factor 2α (eIF2α) and type I IFN, as factors potentiating multiple host-defense mechanisms against viral infection. Following infection of mouse eyes with HSV-1, treatment with the compound dramatically reduced HSV-1 shedding in vivo.


Asunto(s)
Alcaloides de Amaryllidaceae , Antineoplásicos , Herpesvirus Humano 1 , Interferón Tipo I , Ratones , Animales , Antivirales/farmacología , Alcaloides de Amaryllidaceae/farmacología , Fosforilación
17.
Curr Top Behav Neurosci ; 61: 243-264, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36059003

RESUMEN

BACKGROUND: Herpesviruses alter cognitive functions in humans following acute infections; progressive cognitive decline and dementia have also been suggested. It is important to understand the pathogenic mechanisms of such infections. The complement system - comprising functionally related proteins integral for systemic innate and adaptive immunity - is an important component of host responses. The complement system has specialized functions in the brain. Still, the dynamics of the brain complement system are still poorly understood. Many complement proteins have limited access to the brain from plasma, necessitating synthesis and specific regulation of expression in the brain; thus, complement protein synthesis, activation, regulation, and signaling should be investigated in human brain-relevant cellular models. Cells derived from human-induced pluripotent stem cells (hiPSCs) could enable tractable models. METHODS: Human-induced pluripotent stem cells were differentiated into neuronal (hi-N) and microglial (hi-M) cells that were cultured with primary culture human astrocyte-like cells (ha-D). Gene expression analyses and complement protein levels were analyzed in mono- and co-cultures. RESULTS: Transcript levels of complement proteins differ by cell type and co-culture conditions, with evidence for cellular crosstalk in co-cultures. Hi-N and hi-M cells have distinct patterns of expression of complement receptors, soluble factors, and regulatory proteins. hi-N cells produce complement factor 4 (C4) and factor B (FB), whereas hi-M cells produce complement factor 2 (C2) and complement factor 3 (C3). Thus, neither hi-N nor hi-M cells can form either of the C3-convertases - C4bC2a and C3bBb. However, when hi-N and hi-M cells are combined in co-cultures, both types of functional C3 convertase are produced, indicated by elevated levels of the cleaved C3 protein, C3a. CONCLUSIONS: hiPSC-derived co-culture models can be used to study viral infection in the brain, particularly complement receptor and function in relation to cellular "crosstalk." The models could be refined to further investigate pathogenic mechanisms.


Asunto(s)
Infecciones por Herpesviridae , Células Madre Pluripotentes Inducidas , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Complemento C3/metabolismo , Neuronas/metabolismo , Convertasas de Complemento C3-C5/metabolismo , Encéfalo/metabolismo , Infecciones por Herpesviridae/metabolismo
18.
Environ Sci Technol ; 57(47): 18538-18549, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-36240017

RESUMEN

Electrochemical oxidation has been demonstrated to be a useful method for removing biorefractory organic pollutants in mature landfill leachate but suffers from low efficiency in eliminating ammonium because of its resistance to being oxidized by HO• or free chlorine (FC) at decreased pH. Here, we propose a new bipolar membrane-electrochlorination (BPM-EC) process to address this issue. We found that the BPM-EC system was significantly superior to both the undivided and divided reactors with monopolar membranes in terms of elevated rate of ammonium removal, attenuated generation of byproducts (e.g., nitrate and chloramines), increased Faradaic efficiency, and decreased energy consumption. Mechanistic studies revealed that the integration of BPM was helpful in creating alkaline environments in the vicinity of the anode, which facilitated production of surface-bound HO• and FC and eventually promoted in situ generation of ClO•, a crucial reactive species mainly responsible for accelerating ammonium oxidation and selective transformation to nitrogen. The efficacy of BPM-EC in treating landfill leachates with different ammonium concentrations was verified under batch and continuous-flow conditions. A kinetic model that incorporates the key parameters was developed, which can successfully predict the optimal number of BPM-EC reactors (e.g., 2 and 5 for leachates containing 589.4 ± 5.5 and 1258.1 ± 9.6 mg L-1 NH4+-N, respectively) necessary for complete removal of ammonium. These findings reveal that the BPM-EC process shows promise in treating ammonium-containing wastewater, with advantages that include effectiveness, adaptability, and flexibility.


Asunto(s)
Compuestos de Amonio , Contaminantes Químicos del Agua , Aguas Residuales , Compuestos Orgánicos , Nitratos , Oxidación-Reducción , Nitrógeno
19.
Water Res ; 225: 119143, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36182674

RESUMEN

The generation of chlorinated byproducts during the electrochemical oxidation (EO) of Cl--laden wastewater is a significant concern. We aim to propose a concept of converting reactive species (e.g., reactive chlorines and HO• resulting from electrolysis) into 1O2 via the addition of H2O2, which substantially alleviates chlorinated organic formation. When phenol was used as a model organic compound, the results showed that the H2O2-involving EO system outperformed the H2O2-absent system in terms of higher rate constants (5.95 × 10-2 min-1vs. 2.97 × 10-2 min-1) and a much lower accumulation of total organic chlorinated products (1.42 mg L-1vs. 8.18 mg L-1) during a 60 min operation. The rate constants of disappearance of a variety of phenolic compounds were positively correlated with the Hammett constants (σ), suggesting that the reactive species preferred oxidizing phenols with electron-rich groups. After the identification of 1O2 that was abundant in the bulk solution with the use of electron paramagnetic resonance and computational kinetic simulation, the routes of 1O2 generation were revealed. Despite the consensus as to the contribution of reaction between H2O2 and ClO- to 1O2 formation, we conclude that the predominant pathway is through H2O2 reaction with electrogenerated HO• or chlorine radicals (Cl• and Cl2•-) to produce O2•-, followed by self-combination. Density functional theory calculations theoretically showed the difficulty in forming chlorinated byproducts for the 1O2-initiated phenol oxidation in the presence of Cl-, which, by contrast, easily occurred for the Cl•-or HO•-initiated phenol reaction. The experiments run with real coking wastewater containing high-concentration phenols further demonstrated the superiority of the H2O2-involving EO system. The findings imply that this unique method for treating Cl--laden organic wastewater is expected to be widely adopted for generalizing EO technology for environmental applications.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Aguas Residuales/química , Cloro/química , Purificación del Agua/métodos , Fenol/química , Peróxido de Hidrógeno/química , Fenoles , Halógenos/química , Oxidación-Reducción , Cloruros , Contaminantes Químicos del Agua/química , Rayos Ultravioleta
20.
Front Vet Sci ; 9: 973508, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35968005

RESUMEN

Archaea are considered an essential group of gut microorganisms in both humans and animals. However, they have been neglected in previous studies, especially those involving non-ruminants. In this study, we re-analyzed published metagenomic and metatranscriptomic data sequenced from matched samples to explore the composition and the expression activity of gut archaea in ruminants (cattle and sheep) and monogastric animals (pig and chicken). Our results showed that the alpha and beta diversity of each host species, especially cattle and chickens, calculated from metagenomic and metatranscriptomic data were significantly different, suggesting that metatranscriptomic data better represent the functional status of archaea. We detected that the relative abundance of 17 (cattle), 7 (sheep), 20 (pig), and 2 (chicken) archaeal species were identified in the top 100 archaeal taxa when analyzing the metagenomic datasets, and these species were classified as the "active archaeal species" for each host species by comparison with corresponding metatranscriptomic data. For example, The expressive abundance in metatranscriptomic dataset of Methanosphaera cuniculi and Methanosphaera stadtmanae were 30- and 27-fold higher than that in metagenomic abundance, indicating their potentially important function in the pig gut. Here we aim to show the potential importance of archaea in the livestock digestive tract and encourage future research in this area, especially on the gut archaea of monogastric animals.

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