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Microglia phenotypes are highly regulated by the brain environment, but the transcriptional networks that specify the maturation of human microglia are poorly understood. Here, we characterized stage-specific transcriptomes and epigenetic landscapes of fetal and postnatal human microglia and acquired corresponding data in induced pluripotent stem cell (iPSC)-derived microglia, in cerebral organoids, and following engraftment into humanized mice. Parallel development of computational approaches that considered transcription factor (TF) co-occurrence and enhancer activity allowed prediction of shared and state-specific gene regulatory networks associated with fetal and postnatal microglia. Additionally, many features of the human fetal-to-postnatal transition were recapitulated in a time-dependent manner following the engraftment of iPSC cells into humanized mice. These data and accompanying computational approaches will facilitate further efforts to elucidate mechanisms by which human microglia acquire stage- and disease-specific phenotypes.
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Células Madre Pluripotentes Inducidas , Microglía , Humanos , Ratones , Animales , Redes Reguladoras de Genes , Encéfalo , Regulación de la Expresión GénicaRESUMEN
Mouse models for cancer are revealing novel cancer-promoting roles for autophagy. Autophagy promotes tumor growth by suppressing the p53 response, maintaining mitochondrial function, sustaining metabolic homeostasis and survival in stress, and preventing diversion of tumor progression to benign oncocytomas.
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Autofagia , Carcinogénesis , Neoplasias/metabolismo , Animales , Humanos , Neoplasias/patología , Proteína p53 Supresora de Tumor/metabolismo , Proteínas ras/metabolismoRESUMEN
BRCA1 functions at two distinct steps during homologous recombination (HR). Initially, it promotes DNA end resection, and subsequently it recruits the PALB2 and BRCA2 mediator complex, which stabilizes RAD51-DNA nucleoprotein filaments. Loss of 53BP1 rescues the HR defect in BRCA1-deficient cells by increasing resection, suggesting that BRCA1's downstream role in RAD51 loading is dispensable when 53BP1 is absent. Here we show that the E3 ubiquitin ligase RNF168, in addition to its canonical role in inhibiting end resection, acts in a redundant manner with BRCA1 to load PALB2 onto damaged DNA. Loss of RNF168 negates the synthetic rescue of BRCA1 deficiency by 53BP1 deletion, and it predisposes BRCA1 heterozygous mice to cancer. BRCA1+/-RNF168-/- cells lack RAD51 foci and are hypersensitive to PARP inhibitor, whereas forced targeting of PALB2 to DNA breaks in mutant cells circumvents BRCA1 haploinsufficiency. Inhibiting the chromatin ubiquitin pathway may, therefore, be a synthetic lethality strategy for BRCA1-deficient cancers.
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Proteína BRCA1/genética , Cromatina/enzimología , Fibroblastos/enzimología , Haploinsuficiencia , Neoplasias/enzimología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación , Animales , Proteína BRCA2/genética , Línea Celular Tumoral , Cromatina/genética , Daño del ADN , Proteína del Grupo de Complementación N de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación N de la Anemia de Fanconi/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismo , Reparación del ADN por Recombinación , Proteína 1 de Unión al Supresor Tumoral P53/genética , Proteína 1 de Unión al Supresor Tumoral P53/metabolismo , Ubiquitina-Proteína Ligasas/deficiencia , Ubiquitina-Proteína Ligasas/genéticaRESUMEN
Germline mutations of homologous-recombination (HR) genes are among the top contributors to medulloblastomas. A significant portion of human medulloblastomas exhibited genomic signatures of HR defects. We asked whether ablation of Brca2, Palb2, and their related Brca1 and Bccip genes, in the mouse brain can differentially initiate medulloblastomas. We established conditional knockout mouse models of these HR-genes, and a conditional knockdown of Bccip (shBccip-KD). Deletion of any of these genes led to microcephaly and neurological defects, with Brca1- and Bccip- producing the worst. Trp53 co-deletion significantly rescued the microcephaly with Brca1, Palb2, and Brca2 deficiency, but it exhibited limited impact on Bccip- mice. For the first time, inactivation of either Brca1 or Palb2 with Trp53 was found to induce medulloblastomas. Bccip/Trp53 deletions failed, despite that shBccip-CKD was highly penetrative, to induce medulloblastomas. The tumors displayed diverse immunohistochemical features and chromosome copy number variation. While there were widespread upregulations of cell proliferative pathways, most of the tumors expressed biomarkers of the Sonic Hedgehog subgroup. The MBs developed from Brca1-, Palb2-, and Brca2- mice were highly sensitive to a PARP inhibitor, but not the ones from shBccip-CKD mice. Our models recapitulate the spontaneous medulloblastoma development with high penetrance and narrow time-window, providing ideal platforms to test therapeutic agents with the ability to differentiate HR defective and proficient tumors.
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ATR is a key regulator of cell-cycle checkpoints and homologous recombination (HR). Paradoxically, ATR inhibits CDKs during checkpoint responses, but CDK activity is required for efficient HR. Here, we show that ATR promotes HR after CDK-driven DNA end resection. ATR stimulates the BRCA1-PALB2 interaction after DNA damage and promotes PALB2 localization to DNA damage sites. ATR enhances BRCA1-PALB2 binding at least in part by inhibiting CDKs. The optimal interaction of BRCA1 and PALB2 requires phosphorylation of PALB2 at S59, an ATR site, and hypo-phosphorylation of S64, a CDK site. The PALB2-S59A/S64E mutant is defective for localization to DNA damage sites and HR, whereas the PALB2-S59E/S64A mutant partially bypasses ATR for its localization. Thus, HR is a biphasic process requiring both high-CDK and low-CDK periods. As exemplified by the regulation of PALB2 by ATR, ATR promotes HR by orchestrating a "CDK-to-ATR switch" post-resection, directly coupling the checkpoint to HR.
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Roturas del ADN de Doble Cadena , Reparación del ADN por Recombinación , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Quinasas Ciclina-Dependientes/genética , Quinasas Ciclina-Dependientes/metabolismo , Proteína del Grupo de Complementación N de la Anemia de Fanconi , Células HeLa , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosforilación , Unión Proteica , Transducción de Señal , Factores de Tiempo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismoRESUMEN
The PALB2 tumor suppressor plays key roles in DNA repair and has been implicated in redox homeostasis. Autophagy maintains mitochondrial quality, mitigates oxidative stress and suppresses neurodegeneration. Here we show that Palb2 deletion in the mouse brain leads to mild motor deficits and that co-deletion of Palb2 with the essential autophagy gene Atg7 accelerates and exacerbates neurodegeneration induced by ATG7 loss. Palb2 deletion leads to elevated DNA damage, oxidative stress and mitochondrial markers, especially in Purkinje cells, and co-deletion of Palb2 and Atg7 results in accelerated Purkinje cell loss. Further analyses suggest that the accelerated Purkinje cell loss and severe neurodegeneration in the double deletion mice are due to excessive oxidative stress and mitochondrial dysfunction, rather than DNA damage, and partially dependent on p53 activity. Our studies uncover a role of PALB2 in mitochondrial homeostasis and a cooperation between PALB2 and ATG7/autophagy in maintaining redox and mitochondrial homeostasis essential for neuronal survival.
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Autofagia , Mitocondrias , Animales , Autofagia/genética , Proteína 7 Relacionada con la Autofagia/genética , Encéfalo/metabolismo , Proteína del Grupo de Complementación N de la Anemia de Fanconi , Homeostasis/genética , Ratones , Mitocondrias/genética , Mitocondrias/metabolismo , Oxidación-ReducciónRESUMEN
Aristolochic acid analogs (AAAs) are naturally occurring carcinogenic and toxic compounds that pose a safety threat to pharmaceuticals and the environment. It is challenging to screen AAAs due to their lack of characteristic mass spectral fragmentation and their presence of structural diversity. A comprehensive nontargeted screening strategy was proposed by taking into account diverse factors and incorporating various self-developed techniques, and a Python3-based toolkit called AAAs_finder was developed for its implementation. The main procedures consist of virtual structure and ultraviolet and visible (UV) spectra database creation, exact mass and UV spectra-based suspect data extraction, tandem mass spectra (MS/MS) anthropomorphic interpretation, and multicondition retention time (RT) prediction-based candidate structures ranking. To initially assess screening feasibility, eight hypothetical unknown samples were subjected to nontargeted screening using the AAAs_finder toolkit and two other advanced tools. The results showed that the former successfully identified all, while the latter two only managed to identify two and three, respectively, indicating that our strategy was more feasible. After that, the strategy was carefully evaluated for false positives and false negatives, instrument dependence, reproducibility, and sensitivity. After the evaluation, the strategy was successfully applied to the screening of AAAs in real samples, such as herbal medicine, spiked soil, and water. Overall, this study proposed a nontargeted screening strategy and toolkit independent of characteristic mass spectral fragmentation and able to overcome challenges posed by structural diversity for the AAAs screening, which is also valuable for other classes of compounds.
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Ácidos Aristolóquicos , Espectrometría de Masas en Tándem , Reproducibilidad de los Resultados , AguaRESUMEN
This study explores the innovative field of pulsed direct current arc-induced nanoelectrospray ionization mass spectrometry (DCAI-nano-ESI-MS), which utilizes a low-temperature direct current (DC) arc to induce ESI during MS analyses. By employing a 15 kV output voltage, the DCAI-nano-ESI source effectively identifies various biological molecules, including angiotensin II, bradykinin, cytochrome C, and soybean lecithin, showcasing impressive analyte signals and facilitating multicharge MS in positive- and negative-ion modes. Notably, results show that the oxidation of fatty acids using a DC arc produces [M + O - H]- ions, which aid in identifying the location of CâC bonds in unsaturated fatty acids and distinguishing between isomers based on diagnostic ions observed during collision-induced dissociation tandem MS. This study presents an approach for identifying the sn-1 and sn-2 positions in phosphatidylcholine using phosphatidylcholine and nitrate adduct ions, accurately determining phosphatidylcholine molecular configurations via the Paternò-Büchi reaction. With all the advantages above, DCAI-nano-ESI holds significant promise for future analytical and bioanalytical applications.
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Nanotecnología , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Ionización de Electrospray/métodos , Citocromos c/química , Citocromos c/análisis , Bradiquinina/química , Bradiquinina/análisis , Angiotensina II/química , Angiotensina II/análisis , Fosfatidilcolinas/química , Fosfatidilcolinas/análisis , Glycine max/químicaRESUMEN
BACKGROUND AND AIMS: BRCA1 (BRCA1 DNA repair associated) and PALB2 (partner and localizer of BRCA2) interact with each other to promote homologous recombination and DNA double-strand breaks repair. The disruption of this interaction has been reported to play a role in tumorigenesis. However, its precise function in HCC remains poorly understood. APPROACH AND RESULTS: We demonstrated that mice with disrupted BRCA1-PALB2 interaction were more susceptible to HCC than wild-type mice. HCC tumors arising from these mice showed plenty of T-lymphocyte infiltration and a better response to programmed cell death 1 (PD-1) antibody treatment. Mechanistically, disruption of the BRCA1-PALB2 interaction causes persistent high level of DNA damage in HCC cells, leading to activation of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway in both malignant hepatocytes and M1 macrophages in the tumor microenvironment. The activated cGAS-STING pathway induces programmed cell death 1 ligand 1 expression via the STING-interferon regulatory factor 3 (IRF3)-signal transducer and activator of transcription 1 pathway, causing immunosuppression to facilitate tumorigenesis and tumor progression. Meanwhile, M1 macrophages with an activated cGAS-STING pathway could recruit T lymphocytes through the STING-IRF3 pathway, leading to T-lymphocyte infiltration in tumors. After normalizing immune responses by PD-1 antibody treatment, the infiltrating T lymphocytes attack tumor cells rapidly and effectively. CONCLUSIONS: This study reveals that persistent DNA damage caused by a defective BRCA pathway induces tumor immunosuppression and T-lymphocyte infiltration in HCC through the cGAS-STING pathway, providing insight into tumor immune microenvironment remodeling that may help improve HCC response to PD-1 antibody treatment.
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Proteína BRCA1 , Carcinoma Hepatocelular , Proteína del Grupo de Complementación N de la Anemia de Fanconi , Neoplasias Hepáticas , Animales , Ratones , Carcinogénesis , Carcinoma Hepatocelular/inmunología , Proteína del Grupo de Complementación N de la Anemia de Fanconi/metabolismo , Terapia de Inmunosupresión , Neoplasias Hepáticas/inmunología , Nucleotidiltransferasas/metabolismo , Receptor de Muerte Celular Programada 1 , Linfocitos T , Microambiente Tumoral , Proteína BRCA1/metabolismoRESUMEN
Phospholipids (PL) have garnered significant attention due to their physiological activities. Milk and other dairy products are important dietary sources for humans and have been extensively used to analyze the presence of PL by various analytical techniques. In this paper, the analysis techniques of PL were reviewed with the eight trigrams of phospholipidomics and a comprehensive fingerprint of 1295 PLs covering 8 subclasses in milk and other dairy products, especially. Technology is the primary productive force. Based on phospholipidomics technology, we further review the relationship between the composition of PL and factors that may be involved in processing and experimental operation, and emphasized the significance of the biological role played by PL in dietary supplements and biomarkers (production, processing and clinical research), and providing the future research directions.
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RATIONALE: The chemical constituents of traditional Tibetan medicines (TTM) can be identified using high-performance liquid chromatography and high-resolution mass spectrometry (HPLC-MS/MS) technique. However, the HPLC-MS/MS technique requires the sample to be pretreated and then separated using the specific liquid chromatography method, which is time consuming. This study developed a ballpoint electrospray ionization (BPESI) technique for analyzing the chemical constituents of Sbyor-bzo-ghi-wang. This technique is a simple and inexpensive method for the rapid identification of the chemical constituents of TTMs. METHODS: After the important parameters of the homemade BPESI device were optimized, the chemical constituents of Sbyor-bzo-ghi-wang were quickly identified without sample pretreatment. The raw data were converted to mzML file using MSConvert and then identified using SIRIUS 5 software. RESULTS: The results showed that 30 compounds were identified from Sbyor-bzo-ghi-wang, namely eight bile acids, six flavonoids, four alkaloids, three amino acids, and nine others. Compared to the ultra-high-performance liquid chromatography-Q/Orbitrap and high-resolution mass spectrometry (UHPLC-Q/Orbitrap HRMS) technique, the BPESI technique identified almost similar types of compounds and also a comparable number of compounds. CONCLUSIONS: Compared with the traditional HPLC-MS/MS methods, the BPESI technique does not require complex sample pretreatment and subsequent chromatographic separation steps; also it consumes a small quantity of samples. Therefore, BPESI can be used for the qualitative analysis of the chemical constituents of Sbyor-bzo-ghi-wang.
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Medicina Tradicional Tibetana , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Ionización de Electrospray/métodos , Cromatografía Líquida de Alta Presión/métodos , Flavonoides/análisis , Flavonoides/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Alcaloides/análisis , Alcaloides/química , Ácidos y Sales Biliares/análisis , Ácidos y Sales Biliares/química , Aminoácidos/análisis , Aminoácidos/química , Extractos Vegetales/químicaRESUMEN
BACKGROUND AND AIM: Clinical data on the prevalence of metabolic-associated fatty liver disease (MAFLD) in obese and non-obese individuals within a diverse US population is scarce. Furthermore, the influence of physical activity (PA) and dietary quality (DQ) on MAFLD risk remains unclear. This study aims to assess the prevalence and clinical features of MAFLD and examine the relationship between PA and DQ with the risk of developing MAFLD. METHODS AND RESULTS: A cross-sectional analysis of data from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) was conducted. The overall MAFLD prevalence was 41.9%, with 28.6% of participants being obese and 13.4% non-obese. Among those with MAFLD, 67.1% (95% confidence interval (CI): 59.1%-75.1%) were obese, and 32.9% (95% CI: 29.1%-36.7%) were non-obese. Non-obese MAFLD was more frequent in Asians (27.2%), while obese MAFLD was more prevalent in Blacks (66.3%). Metabolic comorbidities were more common in individuals with obese MAFLD, who also exhibited more advanced fibrosis. A high-quality diet (HQD) and increased PA were linked to reduced odds of both obese and non-obese MAFLD (odds ratio (OR) and 95% CI: 0.67 [0.51-0.88] and 0.57 [0.47-0.69]; 0.62 [0.43-0.90] and 0.63 [0.46-0.87], respectively). PA and HQD significantly decreased the risk of obese and non-obese MAFLD (OR and 95% CI: 0.46 [0.33-0.64] and 0.42 [0.31-0.57]). CONCLUSION: A substantial proportion of the US population is affected by both obese and non-obese MAFLD. A strong association exists between a lower risk of both types of MAFLD and adherence to an HQD and engagement in PA.
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Dieta , Enfermedad del Hígado Graso no Alcohólico , Humanos , Encuestas Nutricionales , Estudios Transversales , Dieta/efectos adversos , Obesidad/diagnóstico , Obesidad/epidemiología , Ejercicio Físico , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/epidemiologíaRESUMEN
BRCA1 accumulation at DNA damage sites is an important step for its function in the DNA damage response and in DNA repair. BRCA1-BRCT domains bind to proteins containing the phosphorylated serine-proline-x-phenylalanine (pSPxF) motif including Abraxas, Bach1/FancJ, and CtIP. In this study, we demonstrate that ionizing radiation (IR)-induces ATM-dependent phosphorylation of serine 404 (S404) next to the pSPxF motif. Crystal structures of BRCT/Abraxas show that phosphorylation of S404 is important for extensive interactions through the N-terminal sequence outside the pSPxF motif and leads to formation of a stable dimer. Mutation of S404 leads to deficiency in BRCA1 accumulation at DNA damage sites and cellular sensitivity to IR. In addition, two germline mutations of BRCA1 are found to disrupt the dimer interface and dimer formation. Thus, we demonstrate a mechanism involving IR-induced phosphorylation and dimerization of the BRCT/Abraxas complex for regulating Abraxas-mediated recruitment of BRCA1 in response to IR.
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Proteína BRCA1/metabolismo , Neoplasias Óseas/metabolismo , Proteínas Portadoras/metabolismo , Núcleo Celular/metabolismo , Daño del ADN , Osteosarcoma/metabolismo , Secuencia de Aminoácidos , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteína BRCA1/química , Proteína BRCA1/genética , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Proteínas Portadoras/química , Proteínas Portadoras/genética , Línea Celular Tumoral , Núcleo Celular/patología , Núcleo Celular/efectos de la radiación , Cristalografía por Rayos X , Mutación de Línea Germinal , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Osteosarcoma/genética , Osteosarcoma/patología , Fosforilación , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Interferencia de ARN , Serina , TransfecciónRESUMEN
OBJECTIVE: Accurate delineation of the hippocampal region via magnetic resonance imaging (MRI) is crucial for the prevention and early diagnosis of neurosystemic diseases. Determining how to accurately and quickly delineate the hippocampus from MRI results has become a serious issue. In this study, a pixel-level semantic segmentation method using 3D-UNet is proposed to realize the automatic segmentation of the brain hippocampus from MRI results. METHODS: Two hundred three-dimensional T1-weighted (3D-T1) nongadolinium contrast-enhanced magnetic resonance (MR) images were acquired at Hangzhou Cancer Hospital from June 2020 to December 2022. These samples were divided into two groups, containing 175 and 25 samples. In the first group, 145 cases were used to train the hippocampus segmentation model, and the remaining 30 cases were used to fine-tune the hyperparameters of the model. Images for twenty-five patients in the second group were used as the test set to evaluate the performance of the model. The training set of images was processed via rotation, scaling, grey value augmentation and transformation with a smooth dense deformation field for both image data and ground truth labels. A filling technique was introduced into the segmentation network to establish the hippocampus segmentation model. In addition, the performance of models established with the original network, such as VNet, SegResNet, UNetR and 3D-UNet, was compared with that of models constructed by combining the filling technique with the original segmentation network. RESULTS: The results showed that the performance of the segmentation model improved after the filling technique was introduced. Specifically, when the filling technique was introduced into VNet, SegResNet, 3D-UNet and UNetR, the segmentation performance of the models trained with an input image size of 48 × 48 × 48 improved. Among them, the 3D-UNet-based model with the filling technique achieved the best performance, with a Dice score (Dice score) of 0.7989 ± 0.0398 and a mean intersection over union (mIoU) of 0.6669 ± 0.0540, which were greater than those of the original 3D-UNet-based model. In addition, the oversegmentation ratio (OSR), average surface distance (ASD) and Hausdorff distance (HD) were 0.0666 ± 0.0351, 0.5733 ± 0.1018 and 5.1235 ± 1.4397, respectively, which were better than those of the other models. In addition, when the size of the input image was set to 48 × 48 × 48, 64 × 64 × 64 and 96 × 96 × 96, the model performance gradually improved, and the Dice scores of the proposed model reached 0.7989 ± 0.0398, 0.8371 ± 0.0254 and 0.8674 ± 0.0257, respectively. In addition, the mIoUs reached 0.6669 ± 0.0540, 0.7207 ± 0.0370 and 0.7668 ± 0.0392, respectively. CONCLUSION: The proposed hippocampus segmentation model constructed by introducing the filling technique into a segmentation network performed better than models built solely on the original network and can improve the efficiency of diagnostic analysis.
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Hipocampo , Imagenología Tridimensional , Imagen por Resonancia Magnética , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Imagenología Tridimensional/métodos , Masculino , Persona de Mediana Edad , FemeninoRESUMEN
It has been shown that exposure to hexavalent Chromium, Cr (â ¥), via nasal cavity can have neurotoxicological effects and induces behavioral impairment due to the fact that blood brain barrier (BBB) does not cover olfactory bulb. But whether Cr (â ¥) can cross the BBB and have a toxicological effects in central nervous system (CNS) remains unclear. Therefore, we investigated the effects of Cr (â ¥) on mice treated with different concentrations and exposure time (14 days and 28 days) of Cr (â ¥) via intraperitoneal injection. Results revealed that Cr accumulated in hypothalamus (HY) in a timely dependent manner. Much more severer neuropathologies was observed in the group of mice exposed to Cr (â ¥) for 28 days than that for 14 days. Gliosis, neuronal morphological abnormalities, synaptic degeneration, BBB disruption and neuronal number loss were observed in HY. In terms of mechanism, the Nrf2 related antioxidant stress signaling dysfunction and activated NF-κB related inflammatory pathway were observed in HY of Cr (â ¥) intoxication mice. And these neuropathologies and signaling defects appeared in a timely dependent manner. Taking together, we proved that Cr (â ¥) can enter HY due to weaker BBB in HY and HY is the most vulnerable CNS region to Cr (â ¥) exposure. The concentration of Cr in HY increased along with time. The accumulated Cr in HY can cause BBB disruption, neuronal morphological abnormalities, synaptic degeneration and gliosis through Nrf2 and NF-κB signaling pathway. This finding improves our understanding of the neurological dysfunctions observed in individuals who have occupational exposure to Cr (â ¥), and provided potential therapeutic targets to treat neurotoxicological pathologies induced by Cr (â ¥).
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Barrera Hematoencefálica , FN-kappa B , Ratones , Animales , Barrera Hematoencefálica/metabolismo , FN-kappa B/metabolismo , Cromo/toxicidad , Gliosis , Factor 2 Relacionado con NF-E2/metabolismo , Modelos Animales de Enfermedad , Hipotálamo/metabolismoRESUMEN
Alginate oligosaccharides (AOSs), which are an attractive feed additive for animal production, exhibit pleiotropic bioactivities. In the present study, we investigated graded doses of AOS-mediated alterations in the physiological responses of piglets by determining the intestinal architecture, barrier function, and microbiota. A total of 144 weaned piglets were allocated into four dietary treatments in a completely random design, which included a control diet (CON) and three treated diets formulated with 250 mg/kg (AOS250), 500 mg/kg (AOS500), and 1000 mg/kg AOS (AOS1000), respectively. The trial was carried out for 28 days. Our results showed that AOS treatment reinforced the intestinal barrier function by increasing the ileal villus height, density, and fold, as well as the expression of tight junction proteins, especially at the dose of 500 mg/kg AOS. Meanwhile, supplementations with AOSs showed positive effects on enhancing antioxidant capacity and alleviating intestinal inflammation by elevating the levels of antioxidant enzymes and inhibiting excessive inflammatory cytokines. The DESeq2 analysis showed that AOS supplementation inhibited the growth of harmful bacteria Helicobacter and Escherichia_Shigella and enhanced the relative abundance of Faecalibacterium and Veillonella. Collectively, these findings suggested that AOSs have beneficial effects on growth performance, antioxidant capacity, and gut health in piglets.
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Alginatos , Antioxidantes , Microbioma Gastrointestinal , Oligosacáridos , Destete , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Porcinos , Oligosacáridos/farmacología , Oligosacáridos/administración & dosificación , Antioxidantes/metabolismo , Antioxidantes/farmacología , Alginatos/farmacología , Suplementos Dietéticos , Alimentación Animal , Intestinos/microbiología , Intestinos/efectos de los fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/microbiologíaRESUMEN
Direct construction of chiral S(VI) from prochiral S(II) is a formidable challenge due to the inevitable formation of stable chiral S(IV). Previous synthetic strategies rely on the conversion of chiral S(IV) or enantioselective desymmetrization of preformed symmetrical S(VI) substrates. Here, we report desymmetrizing enantioselective hydrolysis of in situ-generated symmetric aza-dichlorosulfonium from sulfenamides for the preparation of chiral sulfonimidoyl chlorides, which could be used as a general stable synthon for obtaining a series of chiral S(VI) derivatives.
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Ultratrace organic pollutants in the environment pose severe threats to human health; hence, their accurate detection is essential. In this study, we develop a secondary solvent-free enrichment strategy based on bubbling extraction (BE). Especially, we used BE solid-phase microextraction and BE carbon nanotube paper absorption to capture aerosols from a liquid water surface, desorb analytes, and analyze the analytes using mass spectrometry. The application of a solvent-free enrichment strategy helps overcome technical challenges in implementing BE technology, including reproducibility, quantification, and sensitivity. This approach objectively demonstrates the enrichment efficiency of BE, resulting in improved mass spectrometry response and quantification. It effectively tackles the difficulties in detecting and quantifying ultratrace environmental pollutants in mass spectrometric analysis. The present study successfully conducted a quantitative analysis of 16 polycyclic aromatic hydrocarbons and 7 antibiotics in 48 environmental water samples. This strategy proved effective in detecting the presence and distribution of polar and nonpolar environmental pollutants in rivers and lakes. Moreover, this strategy has several advantages, such as ultrahigh sensitivity at the femtograms per liter level, good greenness, multiplexed quantitation, low sample consumption, and ease of operation. Overall, the utilization of the ultrasensitive and environmentally friendly BE approach presents a reliable and adaptable method for the identification of ultratrace environmental pollutants in water specimens, thereby enabling early monitoring of pollutant levels.
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RATIONALE: Microbial metabolites are widely used in agriculture, food, environment, and medicine. However, there is a lack of high-throughput, nonclogging, and simple methods for the identification of microbial metabolites and their subspecies using ambient mass spectrometry (MS). Here, we proposed a method for analyzing the microbial metabolites and identifying their species using the array ballpoint electrospray ionization (aBPESI) technique. METHODS: The previously developed BPESI was combined with the array analysis technique to form a high-throughput analysis technique called aBPESI. The bacteria cultured on the plate medium were directly analyzed using MS with aBPESI. Principal component analysis-linear discriminant analysis (PCA-LDA) algorithm was used to analyze the different subspecies groups. RESULTS: The results showed that aBPESI was capable of completing a sample analysis within 30 s, and the level of metabolite detection was comparable to existing techniques. The accuracy of bacterial subspecies identification was 90% (Pseudomonas aeruginosa) and 100% (Serratia marcescens). CONCLUSIONS: A new high-throughput and robust MS technique aBPESI was proposed. It does not require sample pretreatment and greatly reduces the sample analysis time. aBPESI shows a strong ability in microbial analysis and is expected to be further applied in other research fields.
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Bacterias , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Ionización de Electrospray/métodos , Bacterias/metabolismoRESUMEN
Objective: To distinguish ex vivo normal and abnormal filum terminale (FT) in pathology based on optical coherence tomography (OCT). Methods: A total of 14 ex vivo FTs, freshly imaged via OCT after being cut, were excised from the scanned region for histopathological examination (HPE). Qualitative analysis was performed by 2 blinded assessors. Results: We performed OCT imaging of all specimens and validated them qualitatively. In the fetal FTs, we observed large amounts of fibrous tissue scattered throughout with a few capillaries but no adipose tissue. In tight filum terminale syndrome (TFTS), adipose infiltration and capillaries were significantly increased, with obvious fibroplasia and disarrangement. OCT images showed increased adipose tissue in which the adipocytes were arranged in a grid-like pattern; dense, disordered fibrous tissue and vascular-like tissue were present. The diagnostic results of OCT and HPE were consistent (Kappa = 0.659; P = .009, <.01), and there was no statistically significant difference in diagnosing TFTS using a Chi-square test (P > .05). The area under the curve (AUC) for OCT (AUC = 0.966; 95% CI, 0.903 to 1.000) was better than magnetic resonance imaging (MRI) (AUC = 0.649; 95% CI, 0.403 to 0.896). Conclusion: OCT can quickly obtain clear images of FT's inner structure, contribute to diagnosing TFTS and will be an indispensable complement to MRI and HPE. More FT sample studies in vivo are needed to confirm the high accuracy rate of OCT.