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1.
Cell Mol Biol Lett ; 29(1): 68, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730334

RESUMEN

BACKGROUND: Members of the nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing (NLRP) family regulate various physiological and pathological processes. However, none have been shown to regulate actin cap formation or spindle translocation during the asymmetric division of oocyte meiosis I. NLRP4E has been reported as a candidate protein in female fertility, but its function is unknown. METHODS: Immunofluorescence, reverse transcription polymerase chain reaction (RT-PCR), and western blotting were employed to examine the localization and expression levels of NLRP4E and related proteins in mouse oocytes. small interfering RNA (siRNA) and antibody transfection were used to knock down NLRP4E and other proteins. Immunoprecipitation (IP)-mass spectrometry was used to identify the potential proteins interacting with NLRP4E. Coimmunoprecipitation (Co-IP) was used to verify the protein interactions. Wild type (WT) or mutant NLRP4E messenger RNA (mRNA) was injected into oocytes for rescue experiments. In vitro phosphorylation was employed to examine the activation of steroid receptor coactivator (SRC) by NLRP4E. RESULTS: NLRP4E was more predominant within oocytes compared with other NLRP4 members. NLRP4E knockdown significantly inhibited actin cap formation and spindle translocation toward the cap region, resulting in the failure of polar body extrusion at the end of meiosis I. Mechanistically, GRIN1, and GANO1 activated NLRP4E by phosphorylation at Ser429 and Thr430; p-NLRP4E is translocated and is accumulated in the actin cap region during spindle translocation. Next, we found that p-NLRP4E directly phosphorylated SRC at Tyr418, while p-SRC negatively regulated p-CDC42-S71, an inactive form of CDC42 that promotes actin cap formation and spindle translocation in the GTP-bound form. CONCLUSIONS: NLRP4E activated by GRIN1 and GANO1 regulates actin cap formation and spindle translocation toward the cap region through upregulation of p-SRC-Tyr418 and downregulation of p-CDC42-S71 during meiosis I.


Asunto(s)
Actinas , Meiosis , Oocitos , Proteína de Unión al GTP cdc42 , Animales , Oocitos/metabolismo , Ratones , Femenino , Actinas/metabolismo , Actinas/genética , Proteína de Unión al GTP cdc42/metabolismo , Proteína de Unión al GTP cdc42/genética , Fosforilación , Huso Acromático/metabolismo
2.
Artículo en Inglés | MEDLINE | ID: mdl-38696539

RESUMEN

It is of practical significance to develop polymer-based room-temperature phosphorescence (RTP) materials with ultralong lifetime and multicolor afterglow. Herein, the benzocarbazole derivatives were selected and combined with a poly(vinyl alcohol) (PVA) matrix by a coassembly strategy. Owing to the hydrogen-bonding interactions between benzocarbazole derivatives and the PVA matrix, the nonradiative transition and the quenching of triplet excitons are effectively inhibited. Therefore, the maximum phosphorescence emission lifetime of 2202.17 ms from ABfCz-PVA and the maximum phosphorescence quantum efficiency of 34.97% from ABtCz-PVA were obtained, respectively. In addition, commercially available dye molecules were selected to construct phosphorescent resonance energy transfer (PRET) systems for energy acceptors, enabling full-color afterglow emission in blue, green, yellow, red, and even white. Based on the characteristics of prepared RTP materials, multifunctional applications to flexibility, information encryption, and erasable drawing were deeply explored.

3.
Ophthalmol Retina ; 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38599379

RESUMEN

PURPOSE: In this study, we identify risk factors that predict the progression of acquired vitelliform lesions (AVLs) over time. DESIGN: Retrospective cohort study. SUBJECTS: One hundred sixty-three eyes of 132 patients with a diagnosis of intermediate age-related macular degeneration (iAMD) with AVL. METHODS: This retrospective study evaluated consecutive eyes with AMD from a retina clinic population and included 1181 patients and 2362 eyes. After excluding cases with associated geographic atrophy, macular neovascularization (MNV), vitreomacular traction, and those with <2 years of follow-up data, the final analysis cohort consisted of 163 eyes (132 patients) with ≥1 AVL. The first available visit in which an AVL was evident was considered the baseline visit, and follow-up data were collected from a visit 2 years (± 3 months) later. Progression outcomes at the follow-up visit were classified into 6 categories: resorbed, collapsed, MNV, stable, increasing, and decreasing. Subsequently, we analyzed the baseline characteristics for each category and calculated odds ratios (ORs) to predict these various outcomes. MAIN OUTCOME MEASURES: The study focused on identifying predictive factors influencing the evolution of AVL in iAMD eyes. RESULTS: In total, 163 eyes with AVL had follow-up data at 2 years. The collapsed group demonstrated a significantly greater baseline AVL height and width compared with other groups (P < 0.001). With regard to qualitative parameters, subretinal drusenoid deposits (SDDs) and intraretinal hyperreflective foci (IHRF) at the eye level, AVL located over drusen, and IHRF and external limiting membrane disruption over AVL were significantly more prevalent in the collapsed group compared with other groups (P < 0.05 for all comparisons). Odds ratios for progressing to atrophy after 2 years of follow-up, compared with the resorbed group, were significant for SDD (OR, 2.82; P = 0.048) and AVL height (OR, 1.016; P = 0.006). CONCLUSIONS: The presence of SDDs and greater AVL height significantly increases the risk of developing atrophy at the location of AVL after 2 years of follow-up. These findings may be of value in risk prognostication and defining patient populations for inclusion in future early intervention trials aimed at preventing progression to atrophy. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

4.
bioRxiv ; 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38645138

RESUMEN

Glia derived secretory factors play diverse roles in supporting the development, physiology, and stress responses of the central nervous system (CNS). Through transcriptomics and imaging analyses, we have identified Obp44a as one of the most abundantly produced secretory proteins from Drosophila CNS glia. Protein structure homology modeling and Nuclear Magnetic Resonance (NMR) experiments reveal Obp44a as a fatty acid binding protein (FABP) with a high affinity towards long-chain fatty acids in both native and oxidized forms. Further analyses demonstrate that Obp44a effectively infiltrates the neuropil, traffics between neuron and glia, and is secreted into hemolymph, acting as a lipid chaperone and scavenger to regulate lipid and redox homeostasis in the developing brain. In agreement with this essential role, deficiency of Obp44a leads to anatomical and behavioral deficits in adult animals and elevated oxidized lipid levels. Collectively, our findings unveil the crucial involvement of a noncanonical lipid chaperone to shuttle fatty acids within and outside the brain, as needed to maintain a healthy brain lipid environment. These findings could inspire the design of novel approaches to restore lipid homeostasis that is dysregulated in CNS diseases.

5.
J Cancer Res Clin Oncol ; 150(4): 198, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625586

RESUMEN

PURPOSE: Metabolic reprogramming is currently considered a hallmark of tumor and immune development. It is obviously of interest to identify metabolic enzymes that are associated with clinical prognosis in head and neck squamous cell carcinomas (HNSCC). METHODS: Candidate genes were screened to construct folate metabolism scores by Cox regression analysis. Functional enrichment between high- and low-folate metabolism groups was explored by GO, KEGG, GSVA, and ssGSEA. EPIC, MCPcounter, and xCell were utilized to explore immune cell infiltration between high- and low-folate metabolism groups. Relevant metabolic scores were calculated and visually analyzed by the "IOBR" software package. RESULTS: To investigate the mechanism behind metabolic reprogramming of HNSCC, 2886 human genes associated with 86 metabolic pathways were selected. Folate metabolism is significantly enriched in HNSCC, and that the six-gene (MTHFD1L, MTHFD2, SHMT2, ATIC, MTFMT, and MTHFS) folate score accurately predicts and differentiates folate metabolism levels. Reprogramming of folate metabolism affects CD8T cell infiltration and induces immune escape through the MIF signaling pathway. Further research found that SHMT2, an enzyme involved in folate metabolism, inhibits CD8T cell infiltration and induces immune escape by regulating the MIF/CD44 signaling axis, which in turn promotes HNSCC progression. CONCLUSIONS: Our study identified a novel and robust folate metabolic signature. A folate metabolic signature comprising six genes was effective in assessing the prognosis and reflecting the immune status of HNSCC patients. The target molecule of folate metabolic reprogramming, SHMT2, probably plays a very important role in HNSCC development and immune escape.


Asunto(s)
Neoplasias de Cabeza y Cuello , Transducción de Señal , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Pronóstico , Ácido Fólico , Neoplasias de Cabeza y Cuello/genética
6.
Ophthalmol Retina ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38631656

RESUMEN

PURPOSE: This study aims to define the characteristics of acquired vitelliform lesions (AVLs) in patients with intermediate age-related macular degeneration (iAMD). DESIGN: Retrospective, observational, cross-sectional study SUBJECTS: This study included 217 eyes with AVLs associated with iAMD, and an equivalent number of control patients. METHODS: Optical coherence tomography (OCT) scans were evaluated for qualitative and quantitative parameters at both the eye and lesion level. Eye-level parameters included the presence of: hyporeflective core drusen, intraretinal hyperreflective foci (IHRF), subretinal drusenoid deposits, macular pachyvessels, central retinal thickness, and central choroidal thickness (CCT). Lesion-level qualitative parameters included the presence of ellipsoid zone (EZ) and external limiting membrane disruption overlying the AVL, IHRF overlying the AVL, AVL overlying drusen, pachyvessels under the AVL, a solid core within AVL, and AVL location. Lesion-level quantitative characteristics included AVL height and width, AVL distance from the fovea, and sub-AVL choroidal thickness. MAIN OUTCOME MEASURES: The primary outcomes assessed included the frequency of iHRF, the presence of macular pachyvessels, CCT, and the dimensions (both height and width) of AVLs. RESULTS: Comparing the AVL and control groups, the frequency of IHRF (AVL: 49.3% vs. control: 26.3%) and macular pachyvessels (37.3% vs. 6.9%) was significantly higher in the AVL case group, and the CCT (256.8 ± 88 µm vs. 207.1± 45 µm) was thicker in the AVL group. AVL lesions located over drusen, with overlying IHRF, or situated subfoveally, and AVL lesions with EZ disruption were found to have a greater lesion height and width compared to AVL lesions lacking these characteristics (P-value < 0.001 for all). Additionally, a significant negative correlation was observed between the distance from the fovea and AVL height (Spearman's rho: -0.19, P = 0.002) and width (Spearman's rho: -0.30, P = 0.001). CONCLUSIONS: This study represents the largest reported cohort of AVL lesions associated with iAMD. Novel findings include the higher frequency of pachyvessels in addition to the presence of a thicker choroid in these eyes, as well as the greater height and width of AVL closer to the foveal center. These findings may offer insights into pathophysiologic mechanisms underlying the development of AVL.

7.
JCI Insight ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625743

RESUMEN

Dysregulated lipid homeostasis is emerging as a potential cause of neurodegenerative disorders. However, evidence of errors in lipid homeostasis as a pathogenic mechanism of neurodegeneration remains limited. Here, we show that cerebellar neurodegeneration caused by Sorting Nexin 14 (SNX14) deficiency is associated with lipid homeostasis defects. Recent studies indicate that SNX14 is an inter-organelle lipid transfer protein that regulates lipid transport, lipid droplet (LD) biogenesis, and fatty acid desaturation, suggesting that human SNX14 deficiency belongs to an expanding class of cerebellar neurodegenerative disorders caused by altered cellular lipid homeostasis. To test this hypothesis, we generated a mouse model that recapitulates human SNX14 deficiency at a genetic and phenotypic level. We demonstrate that cerebellar Purkinje cells (PCs) are selectively vulnerable to SNX14 deficiency while forebrain regions preserve their neuronal content. Ultrastructure and lipidomic studies reveal widespread lipid storage and metabolism defects in SNX14 deficient mice. However, pre-degenerating SNX14 deficient cerebella show a unique accumulation of acylcarnitines and depletion of triglycerides. Furthermore, defects in LD content and telolysosome enlargement in pre-degenerating PCs, suggest lipotoxicity as a pathogenic mechanism of SNX14 deficiency. Our work shows a selective cerebellar vulnerability to altered lipid homeostasis and provides a mouse model for future therapeutic studies.

8.
Molecules ; 29(7)2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38611949

RESUMEN

Olibanum is a resinous traditional Chinese medicine that is directly used as a powder. It is widely used in China and is often combined with other traditional Chinese medicine powders to promote blood circulation and relieve pain, as well as to treat rheumatism, rheumatoid arthritis, and osteoarthritis. Powdered traditional Chinese medicine is often easily contaminated by microorganisms and 60Co irradiation is one of the good sterilization methods. Volatile organic compounds (VOCs) are the main active ingredient of olibanum. The aim of this study was to validate the optimum doses of 60Co irradiation and its effect on VOCs. 60Co irradiation was applied in different doses of 0 kGy, 1.5 kGy, 3.0 kGy, and 6.0 kGy. Changes in VOCs were detected using gas chromatography ion mobility spectrometry. A total of 81 VOCs were identified. The odor fingerprint results showed that, with an increase in irradiation dose, most of the VOCs of olibanum changed. Through principal component analysis, cluster analysis, and partial least squares discriminant analysis, it was demonstrated that, at 1.5 kGy, the impact of radiation on the VOCs of olibanum was minimal, indicating this is a relatively good irradiation dose. This study provides a theoretical basis for the irradiation processing and quality control of resinous medicinal materials such as olibanum and it also provides a good reference for irradiation technology development and its application to functional foods, thus making it both significant from a research perspective and useful from an application perspective.


Asunto(s)
Radioisótopos de Cobalto , Olíbano , Compuestos Orgánicos Volátiles , Espectrometría de Movilidad Iónica , Cromatografía de Gases y Espectrometría de Masas , Resinas de Plantas
9.
Artículo en Inglés | MEDLINE | ID: mdl-38682858

RESUMEN

The orexin system is closely related to the pathogenesis of Alzheimer's disease (AD). Orexin-A aggravates cognitive dysfunction and increases amyloid ß (Aß) deposition in AD model mice, but studies of different dual orexin receptor (OXR) antagonists in AD have shown inconsistent results. Our previous study revealed that OX1R blockade aggravates cognitive deficits and pathological progression in 3xTg-AD mice, but the effects of OX2R and its potential mechanism in AD have not been reported. In the present study, OX2R was blocked by oral administration of the selective OX2R antagonist MK-1064, and the effects of OX2R blockade on cognitive dysfunction and neuropsychiatric symptoms in 3xTg-AD mice were evaluated via behavioral tests. Then, immunohistochemistry, western blotting and ELISA were used to detect Aß deposition, tau phosphorylation and neuroinflammation, and electrophysiological and wheel-running activity recording were recorded to observe hippocampal synaptic plasticity and circadian rhythm. The results showed that OX2R blockade ameliorated cognitive dysfunction, improved LTP depression, increased the expression of PSD-95, alleviated anxiety- and depression-like behaviors and circadian rhythm disturbances in 3xTg-AD mice, and reduced Aß pathology, tau phosphorylation and neuroinflammation in the brains of 3xTg-AD mice. These results indicated that chronic OX2R blockade exerts neuroprotective effects in 3xTg-AD mice by reducing AD pathology at least partly through improving circadian rhythm disturbance and the sleep-wake cycle and that OX2R might be a potential target for the prevention and treatment of AD; however, the potential mechanism by which OX2R exerts neuroprotective effects on AD needs to be further investigated.

10.
Brain Behav Immun ; 119: 648-664, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38677623

RESUMEN

The high prevalence of major depressive disorder (MDD) frequently imposes severe constraints on psychosocial functioning and detrimentally impacts overall well-being. Despite the growing interest in the hypothesis of mitochondrial dysfunction, the precise mechanistic underpinnings and therapeutic strategies remain unclear and require further investigation. In this study, an MDD model was established in mice using lipopolysaccharide (LPS). Our research findings demonstrated that LPS exposure induced depressive-like behaviors and disrupted mitophagy by diminishing the mitochondrial levels of PINK1/Parkin in the brains of mice. Furthermore, LPS exposure evoked the activation of the NLRP3 inflammasome, accompanied by a notable elevation in the concentrations of pro-inflammatory factors (TNF-α, IL-1ß, and IL-6). Additionally, neuronal apoptosis was stimulated through the JNK/p38 pathway. The administration of BGP-15 effectively nullified the impact of LPS, corresponding to the amelioration of depressive-like phenotypes and restoration of mitophagy, prevention of neuronal injury and inflammation, and suppression of reactive oxygen species (ROS)-mediated NLRP3 inflammasome activation. Furthermore, we elucidated the involvement of mitophagy in BGP-15-attenuated depressive-like behaviors using the inhibitors targeting autophagy (3-MA) and mitophagy (Mdivi-1). Notably, these inhibitors notably counteracted the antidepressant and anti-inflammatory effects exerted by BGP-15. Based on the research findings, it can be inferred that the antidepressant properties of BGP-15 in LPS-induced depressive-like behaviors could potentially be attributed to the involvement of the mitophagy pathway. These findings offer a potential novel therapeutic strategy for managing MDD.

11.
Heliyon ; 10(7): e28897, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38596102

RESUMEN

Although considerable research has been devoted to improving safety in university laboratories, accidents, in that environment, have still occurred frequently at the cost of serious injury or even death of laboratory personnel. Currently, few Human Reliability Analyses (HRA) have been conducted with respect to a university laboratory. The aim of the research was to conduct a reliability study relating to human behaviour in a university laboratory to explore quantitatively the causes and influencing factors relating to the frequency of laboratory accidents. Improved Cognitive Reliability and Error Analysis Method (CREAM) and improved Standardized Plant Analysis Risk HRA (SPAR-H) were employed to assess Human Error Probability (HEP) of 23 subjects. The HEP calculated through improved CREAM proved more accurate than results obtained through improved SPAR-H. Unexpectedly, the results demonstrated that under similar environmental conditions, the HEP of subjects did not decrease with an increase in educational background, including additional experimental time and experience. Moreover, environmental conditions exerted greater impact on personnel reliability than Human Inherent Factors (HIFs) in laboratories. It is anticipated that the study would provide valuable insights, in respect of research methods, and to serve as a practical basis for lowering the accident rate in university laboratories.

12.
Clin Rheumatol ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38587715

RESUMEN

OBJECTIVES: This study aimed at identifying clinical and laboratory risk factors for myocardial involvement (MI) in idiopathic inflammatory myopathies (IIMs) patients as well as constructing a risk-predicted nomogram for prediction and early identification of MI. METHODS: An IIMs cohort in southeastern China was constructed, including 504 adult IIMs patients who met the inclusion and exclusion criteria, and were hospitalized at four divisions of the First Affiliated Hospital, Zhejiang University School of Medicine from January 1st 2018 to April 30st 2022. After dividing patients into the training cohort and the validation cohort, risk factors for MI were identified through least absolute shrinkage and selection operator regression and multivariate logistic regression. A risk-predicted nomogram was established and validated internally and externally for discrimination, calibration and practicability. RESULTS: In this cohort, 17.7% of patients developed MI and the survival was significantly inferior to that of IIMs patients without MI (P < 0.001). In the training cohort, age > 55 years old (P < 0.001), disease activity > 10 points (P < 0.001), interleukin-17A (IL-17A) > 7.5 pg/ml (P < 0.001), lactic dehydrogenase (LDH) > 425 U/L (P < 0.001), anti-mitochondrial antibodies (AMAs, P = 0.017), and anti-MDA5 antibody (P = 0.037) were significantly correlated with development of MI. A nomogram was established by including the above values to predict MI and was found efficient in discrimination, calibration, and practicability through internal and external validation. CONCLUSION: This study developed and validated a nomogram model to predict the risk of MI in adult IIMs patients, which can benefit the prediction and early identification of MI as well as timely intervention in these patients.

13.
Curr Eye Res ; : 1-7, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639042

RESUMEN

PURPOSE: Intraretinal hyper-reflective foci (IHRF) are optical coherence tomography (OCT) risk factors for progression of age-related macular degeneration (AMD). In this study we assess the change in the number and distribution of IHRF over two years. METHODS: The axial distribution of IHRF were quantified in eyes with intermediate AMD (iAMD) at baseline and 24 months, using a series of 5 sequential equidistant en face OCT retinal slabs generated between the outer border of the internal limiting membrane (ILM) and the inner border of the retinal pigment epithelium (RPE). Following thresholding and binarization, IHRF were quantified in each retinal slab using ImageJ. The change in IHRF number in each slab between baseline and month 24 was calculated. RESULTS: Fifty-two eyes showed evidence of IHRF at baseline, and all continued to show evidence of IHRF at 24 months (M24). The total average IHRF count/eye increased significantly from 4.67 ± 0.63 at baseline to 11.62 ± 13.86 at M24 (p < 0.001) with a mean increase of 6.94 ± 11.12 (range: - 9 to + 60). Overall, at M24, 76.9% eyes showed an increase in IHRF whereas 15.4% of eyes showed a decrease (3 eyes [5.7%] showed no change). There was a greater number of IHRF and a greater increase in IHRF over M24 in the outer slabs. CONCLUSIONS: IHRF are most common in the outer retinal layers and tend to increase in number over time. The impact of the distribution and frequency of these IHRF on the overall progression of AMD requires further study.

14.
Neural Regen Res ; 19(10): 2299-2309, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38488564

RESUMEN

JOURNAL/nrgr/04.03/01300535-202410000-00031/figure1/v/2024-02-06T055622Z/r/image-tiff Glutamate excitotoxicity has been shown to play an important role in glaucoma, and glutamate can induce ferroptosis. The p38 mitogen-activated protein kinase (MAPK) pathway inhibitor SB202190 has a potential ability to suppress ferroptosis, and its downstream targets, such as p53, have been shown to be associated with ferroptosis. However, whether ferroptosis also occurs in retinal ganglion cells in response to glutamate excitotoxicity and whether inhibition of ferroptosis reduces the loss of retinal ganglion cells induced by glutamate excitotoxicity remain unclear. This study investigated ferroptosis in a glutamate-induced glaucoma rat model and explored the effects and molecular mechanisms of SB202190 on retinal ganglion cells. A glutamate-induced excitotoxicity model in R28 cells and an N-methyl-D-aspartate-induced glaucoma model in rats were used. In vitro experiments showed that glutamate induced the accumulation of iron and lipid peroxide and morphological changes of mitochondria in R28 cells, and SB202190 inhibited these changes. Glutamate induced the levels of p-p38 MAPK/p38 MAPK and SAT1 and decreased the expression levels of ferritin light chain, SLC7A11, and GPX4. SB202190 inhibited the expression of iron death-related proteins induced by glutamate. In vivo experiments showed that SB202190 attenuated N-methyl-D-aspartate-induced damage to rat retinal ganglion cells and improved visual function. These results suggest that SB202190 can inhibit ferroptosis and protect retinal ganglion cells by regulating ferritin light chain, SAT1, and SLC7A11/Gpx4 pathways and may represent a potential retina protectant.

15.
J Environ Radioact ; 275: 107428, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38547560

RESUMEN

In order to investigate the impact of environmental conditions on the distribution and migration of 90Sr in the Longji terrace environment, the activity concentrations of 90Sr and 137Cs were determined. The activity concentration ranges of 90Sr and 137Cs in surface soil were 0.15-1.04 Bq/kg and 2.16-6.94 Bq/kg, respectively. These results showed that there was a similar trend between the activity concentration of 90Sr and 137Cs in the surface soil along the runoff path and their activity concentration were influenced by the slope of the terraced terrain. On the other hand, the activity ranges of 90Sr and 137Cs in soil cores were 0.01-2.74 Bq/kg and 0.43-7.19 Bq/kg, respectively. These results indicate that the migration mechanism of 90Sr is different from that of 137Cs. As compared with 137Cs, 90Sr is significantly influenced by the moisture content. In addition, high span of 137Cs/90Sr activity ratios were found in this study, which were attributed to the characteristics of cultivated land and frequent artificial disturbances that intensified the migration of 90Sr.


Asunto(s)
Radioisótopos de Cesio , Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Radioisótopos de Estroncio , Radioisótopos de Cesio/análisis , Radioisótopos de Estroncio/análisis , Contaminantes Radiactivos del Suelo/análisis
16.
J Control Release ; 368: 430-443, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38447813

RESUMEN

Limited drug loading and incomplete drug release are two major obstacles that traditional polymeric microneedles (MNs) have to overcome. For smart controlled-release MNs, since drug release duration is uncertain, a clear indication of the finish of drug release is also important for patient guidance on the timing of the next dose. In this study, MN with a triple structure of a glucose-responsive shell, loaded insulin powders and a colored propelling inner core (inspired by the mechanism of osmotic pump) was innovatively constructed. The MN patch could release insulin according to blood glucose levels (BGLs) and had excellent drug loading, more complete drug release, and good drug stability, which significantly prolonged the normoglycemic time. An approximately 0.3 cm2 patch has a hypoglycemic effect on diabetic mice for up to 24 h. Moreover, the fading of the inner core could indicate the release process of the loaded drug and can help to facilitate uninterrupted closed loop therapy for patients. The designed triple MN structure is also suitable, and can be used in the design of other smart MN drug delivery systems to further improve their drug loading capacity and simultaneously achieve more complete, smart controlled and visualized drug release.


Asunto(s)
Diabetes Mellitus Experimental , Humanos , Ratones , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Agujas , Sistemas de Liberación de Medicamentos , Insulina , Glucosa , Administración Cutánea
17.
Neurosci Lett ; 825: 137700, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38401642

RESUMEN

Multiple biological functions of MTMR14 including regulation of autophagy, inflammation and Ca2+ homeostasis have been reported. However, its functional contribution to learning and memory remains unclear. In this study, we investigated whether upregulation of MTMR14 induced cognitive impairment and the underlying mechanisms. MTMR14 level was significantly increased in cells or brain tissues that overexpressed P301S-tau. The fusion of autophagosome and lysosome was significantly inhibited by overexpression of MTMR14 or P301S-tau. Upregulation of MTMR14 led to cognitive impairments in 2-month-old mice by inhibiting synaptic protein expression. These findings suggest that MTMR14 may be a key risk factor for cognitive ability.


Asunto(s)
Enfermedad de Alzheimer , Proteínas tau , Ratones , Animales , Regulación hacia Arriba , Aprendizaje por Laberinto/fisiología , Ratones Transgénicos , Proteínas tau/metabolismo , Modelos Animales de Enfermedad , Enfermedad de Alzheimer/metabolismo , Monoéster Fosfórico Hidrolasas/genética
18.
Microsyst Nanoeng ; 10: 23, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38317693

RESUMEN

Extracellular vesicles (EVs) have been identified as promising biomarkers for the noninvasive diagnosis of various diseases. However, challenges in separating EVs from soluble proteins have resulted in variable EV recovery rates and low purities. Here, we report a high-yield ( > 90%) and rapid ( < 10 min) EV isolation method called FLocculation via Orbital Acoustic Trapping (FLOAT). The FLOAT approach utilizes an acoustofluidic droplet centrifuge to rotate and controllably heat liquid droplets. By adding a thermoresponsive polymer flocculant, nanoparticles as small as 20 nm can be rapidly and selectively concentrated at the center of the droplet. We demonstrate the ability of FLOAT to separate urinary EVs from the highly abundant Tamm-Horsfall protein, addressing a significant obstacle in the development of EV-based liquid biopsies. Due to its high-yield nature, FLOAT reduces biofluid starting volume requirements by a factor of 100 (from 20 mL to 200 µL), demonstrating its promising potential in point-of-care diagnostics.

19.
Proc Natl Acad Sci U S A ; 121(9): e2315956121, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38377201

RESUMEN

Photo-catalytic CO2 reduction with perovskite quantum dots (QDs) shows potential for solar energy storage, but it encounters challenges due to the intricate multi-electron photoreduction processes and thermodynamic and kinetic obstacles associated with them. This study aimed to improve photo-catalytic performance by addressing surface barriers and utilizing multiple-exciton generation in perovskite QDs. A facile surface engineering method was employed, involving the grafting of ferrocene carboxylic acid (FCA) onto CsPbBr3 (CPB) QDs, to overcome limitations arising from restricted multiple-exciton dissociation and inefficient charge transfer dynamics. Kelvin Probe Force Microscopy and XPS spectral confirmed successfully creating an FCA-modulated microelectric field through the Cs active site, thus facilitating electron transfer, disrupting surface barrier energy, and promoting multi-exciton dissociations. Transient absorption spectroscopy showed enhanced charge transfer and reduced energy barriers, resulting in an impressive CO2-to-CO conversion rate of 132.8 µmol g-1 h-1 with 96.5% selectivity. The CPB-FCA catalyst exhibited four-cycle reusability and 72 h of long-term stability, marking a significant nine-fold improvement compared to pristine CPB (14.4 µmol g-1 h-1). These results provide insights into the influential role of FCA in regulating intramolecular charge transfer, enhancing multi-exciton dissociation, and improving CO2 photoreduction on CPB QDs. Furthermore, these findings offer valuable knowledge for controlling quantum-confined exciton dissociation to enhance CO2 photocatalysis.

20.
Sci Bull (Beijing) ; 69(7): 901-912, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38302334

RESUMEN

Perovskite quantum dots (PQDs) hold immense potential as photocatalysts for CO2 reduction due to their remarkable quantum properties, which facilitates the generation of multiple excitons, providing the necessary high-energy electrons for CO2 photoreduction. However, harnessing multi-excitons in PQDs for superior photocatalysis remains challenging, as achieving the concurrent dissociation of excitons and interparticle energy transfer proves elusive. This study introduces a ligand density-controlled strategy to enhance both exciton dissociation and interparticle energy transfer in CsPbBr3 PQDs. Optimized CsPbBr3 PQDs with the regulated ligand density exhibit efficient photocatalytic conversion of CO2 to CO, achieving a 2.26-fold improvement over unoptimized counterparts while maintaining chemical integrity. Multiple analytical techniques, including Kelvin probe force microscopy, temperature-dependent photoluminescence, femtosecond transient absorption spectroscopy, and density functional theory calculations, collectively affirm that the proper ligand termination promotes the charge separation and the interparticle transfer through ligand-mediated interfacial electron coupling and electronic interactions. This work reveals ligand density-dependent variations in the gas-solid photocatalytic CO2 reduction performance of CsPbBr3 PQDs, underscoring the importance of ligand engineering for enhancing quantum dot photocatalysis.

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