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BMC Gastroenterol ; 24(1): 308, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261771

RESUMEN

BACKGROUND: The netrin-1/CD146 pathway regulates colorectal cancer (CRC) liver metastasis, angiogenesis, and vascular development. However, few investigations have yet examined the biological function of netrin-1/CD146 complex in CRC. In this work, we investigated the relationship between the netrin-1/CD146 axis and S100 proteins in sentinel lymph node, and revealed a possible new clue for vascular metastasis of CRC. METHODS: The expression levels of netrin-1 and CD146 proteins in CRC, as well as S100A8 and S100A9 proteins in the sentinel lymph nodes were determined by immunohistochemistry. Using GEPIA and UALCAN, we analyzed netrin-1 and CD146 gene expression in CRC, their association with CRC stage, and their expression levels and prognosis in CRC patients. RESULTS: The expression level of netrin-1 in N1a+1b (CRC lymphatic metastasis groups, exculded N1c) was positively increased with N0 (p = 0.012). The level of netrin-1 protein was positively correlated with CD146 protein (p < 0.05). The level of S100A9 protein was positively correlated with CD146 protein (r = 0.492, p = 0.007). Moreover, netrin-1 expression was obviously correlated with S100A9 expression in the N1 stage (r = 0.867, p = 0.000). CD146 level was correlated with S100A9 level in the N2 stage (r = 0.731, p = 0.039). CD146 mRNA expression was higher in normal colorectal tissues than in CRC (p < 0.05). Netrin-1 and CD146 expression were not significantly associated with the tumor stages and prognosis of patients with CRC (p > 0.05). CONCLUSIONS: The netrin-1/CD146 and netrin-1/S100A9 axis in CRC tissues might related with early stage of lymph node metastasis, thus providing potential novel channels for blocking lymphatic metastasis and guiding biomarker discovery in CRC patients.


Asunto(s)
Antígeno CD146 , Calgranulina B , Neoplasias Colorrectales , Metástasis Linfática , Netrina-1 , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Calgranulina A/genética , Calgranulina A/metabolismo , Calgranulina B/genética , Calgranulina B/metabolismo , Antígeno CD146/genética , Antígeno CD146/metabolismo , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Ganglios Linfáticos/patología , Ganglios Linfáticos/metabolismo , Metástasis Linfática/genética , Metástasis Linfática/patología , Estadificación de Neoplasias , Netrina-1/metabolismo , Netrina-1/genética , Pronóstico
3.
Bioresour Technol ; 413: 131510, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39307476

RESUMEN

The use of microalgae for antibiotic removal has received increasing attention due to its many advantages. However, challenges such as limited removal rates and the complexity of algae cell recovery persist. In this study, chitosan and FeCl3 modified peanut shell biochar (CTS@FeBC) was prepared for the immobilization of Chlorella pyrenoidosa. The results showed that CTS@FeBC effectively adsorbed and immobilized microalgal cells to form microalgae-biochar hybrids, resulting in higher sulfamethoxazole removal rate (45.7 %) compared to microalgae (34.4 %) or biochar (20.0 %) alone, and higher microalgal lipid yield (11.6 mg/L d-1) than microalgae alone (10.1 mg/L d-1). More importantly, the microalgae-biochar hybrids could be rapidly separated from the wastewater within 10 min by applying a magnetic field, resulting in a harvesting efficiency of 86.3 %. Overall, the microalgae-biochar hybrids hold great potential in overcoming challenges associated with pollutants removal and microalgal biomass recovery.

4.
Syst Biol ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39283716

RESUMEN

Despite significant advances in phylogenetics over the past decades, the deep relationships within Bivalvia (phylum Mollusca) remain inconclusive. Previous efforts based on morphology or several genes have failed to resolve many key nodes in the phylogeny of Bivalvia. Advances have been made recently using transcriptome data, but the phylogenetic relationships within Bivalvia historically lacked consensus, especially within Pteriomorphia and Imparidentia. Here, we inferred the relationships of key lineages within Bivalvia using matrices generated from specifically designed ultraconserved elements (UCEs) with 16 available genomic resources and 85 newly sequenced specimens from 55 families. Our new probes (Bivalve UCE 2k v.1) for target sequencing captured an average of 849 UCEs with 1085-bp in mean length from in vitro experiments. Our results introduced novel schemes from six major clades (Protobranchina, Pteriomorphia, Palaeoheterodonta, Archiheterodonta, Anomalodesmata and Imparidentia), though some inner nodes were poorly resolved, such as paraphyletic Heterodonta in some topologies potentially due to insufficient taxon sampling. The resolution increased when analyzing specific matrices for Pteriomorphia and Imparidentia. We recovered three Pteriomorphia topologies different from previously published trees, with the strongest support for ((Ostreida + (Arcida + Mytilida)) + (Pectinida + (Limida + Pectinida))). Limida were nested within Pectinida, warranting further studies. For Imparidentia, our results strongly supported the new hypothesis of (Galeommatida + (Adapedonta + Cardiida)), while the possible non-monophyly of Lucinida was inferred but poorly supported. Overall, our results provide important insights into the phylogeny of Bivalvia and show that target enrichment sequencing of UCEs can be broadly applied to study both deep and shallow phylogenetic relationships.

5.
Aging (Albany NY) ; 16(17): 12277-12292, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39264588

RESUMEN

EGFR-TKIs have been used as frontline treatment in patients with advanced non-small cell lung cancer (NSCLC) suffering from the EGFR mutation. Gefitinib, the first-generation EGFR-TKI, has greatly improved survival rates in lung cancer patients, whereas acquired gefitinib resistance is still a critical issue that needs to be overcome. In our research, high expression levels of CIB2 were found in gefitinib-resistant lung cancer cells. CIB2 knockout rendered gefitinib-resistant cells more sensitive to gefitinib, and overexpression of CIB2 in parental cells was sufficient to induce more resistance to gefitinib. Inhibition of CIB2 in gefitinib-resistant lung cancer cells significantly induced cell apoptosis. To clarify the major molecular mechanism by which CIB2 increases gefitinib resistance, we demonstrated that raised CIB2 in lung cancer cells promoted epithelial-to-mesenchymal transition (EMT) through upregulation of ZEB1. Moreover, FOSL1 transcriptionally regulated CIB2 expression. Finally, CIB2 rendered tumors resistant to gefitinib treatment in vivo. Our results explored a new mechanism: upregulated CIB2 promoted EMT through ZEB1 to regulate gefitinib resistance, which could be a candidate therapeutic target for overcoming acquired resistance to EGFR-TKIs in NSCLC patients.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Resistencia a Antineoplásicos , Transición Epitelial-Mesenquimal , Gefitinib , Neoplasias Pulmonares , Homeobox 1 de Unión a la E-Box con Dedos de Zinc , Gefitinib/farmacología , Gefitinib/uso terapéutico , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética , Humanos , Resistencia a Antineoplásicos/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Proteínas de Unión al Calcio/metabolismo , Proteínas de Unión al Calcio/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Animales , Ratones , Apoptosis/efectos de los fármacos , Receptores ErbB/metabolismo , Receptores ErbB/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-fos/genética
6.
J Orthop Surg Res ; 19(1): 611, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39342292

RESUMEN

BACKGROUND: Shear Wave Elastography (SWE) offers quantitative insights into the hardness and elasticity characteristics of tissues. The objective of this study is to investigate the correlation between SWE of the menisci and MRI-assessed degenerative changes in the menisci, with the aim of providing novel reference source for improving non-invasive evaluation of meniscal degenerative alterations. METHODS: The participants in this study were selected from patients who underwent knee joint MRI scans at our hospital from February 2023 to February 2024. The anterior horns of both the medial and lateral menisci were evaluated using SWE technique. The differences in elastic values of meniscus among different MRI grades were compared. The correlation between elastic values and MRI grades, as well as various parameters, was analyzed. Using MRI Grade 3 as the gold standard, the optimal cutoff value for meniscal tear was determined. The intraclass correlation coefficient (ICC) was employed to evaluate the reliability of repeated measurements performed by the same observer. RESULTS: A total of 104 female participants were enrolled in this study, with 152 lateral menisci (LM) and 144 medial menisci (MM) assessed. For the male group, 83 individuals were included, with 147 LM and 145 MM evaluated. The results demonstrated statistically significant differences in the elasticity values of the menisci at the same anatomical sites across different MRI grades (P < 0.001). Within the same grade, the MM had higher elasticity values than the LM, showing a statistically significant difference (P < 0.001). The elasticity values of the menisci were higher in males compared to females. There were statistically significant positive correlations between the elasticity values of the menisci and age, BMI, and MRI grade. The ICC for repeated measurements within the observer demonstrated good reliability (> 0.79). CONCLUSIONS: The meniscal elasticity values measured by SWE exhibit a significant positive correlation with the grades of degeneration assessed by MRI. Furthermore, the elasticity values of the meniscus are found to increase with advancing age and elevated BMI.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Imagen por Resonancia Magnética , Meniscos Tibiales , Humanos , Diagnóstico por Imagen de Elasticidad/métodos , Femenino , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Adulto , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/patología , Anciano , Reproducibilidad de los Resultados , Adulto Joven , Lesiones de Menisco Tibial/diagnóstico por imagen , Elasticidad
7.
Nat Commun ; 15(1): 8081, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39278973

RESUMEN

The metabolomic profile of aging is complex. Here, we analyse 325 nuclear magnetic resonance (NMR) biomarkers from 250,341 UK Biobank participants, identifying 54 representative aging-related biomarkers associated with all-cause mortality. We conduct genome-wide association studies (GWAS) for these 325 biomarkers using whole-genome sequencing (WGS) data from 95,372 individuals and perform multivariable Mendelian randomization (MVMR) analyses, discovering 439 candidate "biomarker - disease" causal pairs at the nominal significance level. We develop a metabolomic aging score that outperforms other aging metrics in predicting short-term mortality risk and exhibits strong potential for discriminating aging-accelerated populations and improving disease risk prediction. A longitudinal analysis of 13,263 individuals enables us to calculate a metabolomic aging rate which provides more refined aging assessments and to identify candidate anti-aging and pro-aging NMR biomarkers. Taken together, our study has presented a comprehensive aging-related metabolomic profile and highlighted its potential for personalized aging monitoring and early disease intervention.


Asunto(s)
Envejecimiento , Bancos de Muestras Biológicas , Biomarcadores , Estudio de Asociación del Genoma Completo , Metabolómica , Humanos , Envejecimiento/genética , Envejecimiento/metabolismo , Reino Unido/epidemiología , Masculino , Femenino , Metabolómica/métodos , Anciano , Persona de Mediana Edad , Biomarcadores/metabolismo , Análisis de la Aleatorización Mendeliana , Espectroscopía de Resonancia Magnética , Metaboloma , Estudios Longitudinales , Secuenciación Completa del Genoma , Adulto , Anciano de 80 o más Años , Biobanco del Reino Unido
8.
Ecol Evol ; 14(9): e70260, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39247167

RESUMEN

For decades, many marine animals have been considered to exhibit cosmopolitan or transoceanic distribution. This situation is prevalent in Asia, where many species were collected and named by American or European experts in the 1700s to early 1900s. Using the windowpane oysters Placuna-a small genus of bivalves with five recognized species-we show that careful analysis is required to reassess the validity of these species. Currently, only two species of Placuna (P. placenta and P. ephippium) widely reported in the Indo-Pacific region have been recorded from Chinese coastal waters. Here, we described two new species of Placuna from China. Placuna vitream sp. nov. can be distinguished from P. placenta by its larger ridge angle. Phylogenetic analysis using five gene fragments fully supported that P. vitream sp. nov. is a sister to the specimen from Singapore identified as P. placenta and more distant from other Placuna species with available molecular data. Besides, based on subfossil shells, we describe Placuna aestuaria sp. nov. that differs from its congeneric species by its broad hinge, medium ridge angle, and nearly straight ridges. Finally, we suggest a combination of hinge structure and ridge angle that can be used for identifying Placuna species and preparing a key to this genus. Our findings of two new species expand the diversity of Placuna and prompt reassessment of the many presumably widely distributed marine species in Asia.

9.
Angew Chem Int Ed Engl ; : e202413071, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103902

RESUMEN

A rapid in situ synthesis of electrochromic covalent organic frameworks (EC-COFs) was proposed by using green electrochemical interface polymerization of N,N,N',N'-tetrakis(4-aminophenyl)-1,4-benzenediamine (TPDA) and 2,5-dihydroxyterephthalaldehyde (DHBD). The synthetized TPDA-DHBD films exhibit stable polymorphic color variations under different applied potentials, which can be attributed to the redox state changes of bis(triphenylamine) and imine electroactive functional groups within the COFs skeleton. TPDA-DHBD represents markedly different electrochromisms from red to cyan due to the steric hindrance effect caused by the presence of UO2 2+, demonstrating the unique tunability of COFs materials. This work offers a new feasible idea for rapid EC-COFs synthesis and tunable EC-COFs realization.

10.
Free Radic Biol Med ; 224: 382-392, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39209136

RESUMEN

Cellular senescence is a natural barrier of the transition from premalignant cells to invasive cancer. Pharmacological induction of senescence has been proposed as a possible anticancer strategy. In this study, we found that deoxyarbutin inhibited the growth of glioblastoma (GBM) cells by inducing cellular senescence, independent of tyrosinase expression. Instead, deoxyarbutin induced mitochondrial oxidative stress and damage. These aberrant mitochondria were key to the p53-dependent senescence of GBM cells. Facilitating autophagy or mitigating mitochondrial oxidative stress both suppressed p53 expression and alleviated cellular senescence induced by deoxyarbutin. Thus, our study reveals that deoxyarbutin induces mitochondrial oxidative stress to trigger the p53-dependent senescence of GBM cells. Importantly, deoxyarbutin treatment resulted in accumulation of p53, induction of cellular senescence, and inhibition of tumor growth in a subcutaneous tumor model of mouse. In conclusion, our study reveals that deoxyarbutin has therapeutic potential for GBM by inducing mitochondrial oxidative stress for p53-dependent senescence of GBM cells.

11.
Environ Int ; 190: 108867, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38968833

RESUMEN

Organotin compounds (OTs) are endocrine disruptors that induce imposex in hundreds of gastropods, but little is known about their underlying molecular mechanisms. This study aimed to investigate the endocrine toxicity and molecular responses to tributyltin (TBT) and triphenyltin (TPT) exposure in the whelk Reishia clavigera, which often serves as a biomonitor for OT contamination. Over a 120-day exposure to environmentally relevant concentrations of TBT (1000 ng L-1) and TPT (500 ng L-1), we observed a significant increase in penis length in both male and female whelks. Notably, TPT exhibited a stronger potency in inducing pseudo-penis development and female sterility, even at a half dose of TBT. Bioaccumulation analysis also revealed higher persistence and accumulation of TPT in whelk tissues compared to TBT. Differential expression analysis identified a substantial number of differentially expressed genes (DEGs), with TPT exposure eliciting more DEGs than TBT. Our results demonstrated that OTs induced xenobiotic metabolism and metabolic dysregulation in the digestive gland, impaired multiple cellular functions and triggered neurotoxicity in the nervous system, and disrupted lipid homeostasis and oxidative stress in the gonads. Furthermore, imposex was possibly associated with disturbances in retinoic acid metabolism, nuclear receptor signaling, and neuropeptide activity. When compared to TBT, TPT exhibited a more pronounced endocrine-disrupting effect, attributable to its higher bioaccumulation and substantial interruption of transcriptional regulation, OT detoxification, and biosynthesis of retinoic acids in R. clavigera. Our results, therefore, highlight the importance of considering the differences in bioaccumulation and molecular toxicity between TBT and TPT in future risk assessments of these contaminants. Overall, our study provided molecular insights into the toxicity and transcriptome profiles in R. clavigera exposed to TBT and TPT, shedding light on the endocrine-disrupting effects and reproductive impairment in female gastropods.


Asunto(s)
Disruptores Endocrinos , Gastrópodos , Perfilación de la Expresión Génica , Compuestos Orgánicos de Estaño , Compuestos de Trialquiltina , Contaminantes Químicos del Agua , Animales , Compuestos de Trialquiltina/toxicidad , Compuestos Orgánicos de Estaño/toxicidad , Disruptores Endocrinos/toxicidad , Gastrópodos/efectos de los fármacos , Gastrópodos/genética , Femenino , Masculino , Contaminantes Químicos del Agua/toxicidad , Transcriptoma/efectos de los fármacos , Trastornos del Desarrollo Sexual/inducido químicamente
12.
World J Psychiatry ; 14(6): 838-847, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38984342

RESUMEN

BACKGROUND: Older adults are at high risk of femoral neck fractures (FNFs). Elderly patients face and adapt to significant psychological burdens, resulting in different degrees of psychological stress response. Total hip replacement is the preferred treatment for FNF in elderly patients; however, some patients have poor postoperative prognoses, and the underlying mechanism is unknown. We speculated that the postoperative prognosis of elderly patients with FNF may be related to preoperative psychological stress. AIM: To explore the relationship between preoperative psychological stress and the short-term prognosis of elderly patients with FNF. METHODS: In this retrospective analysis, the baseline data, preoperative 90-item Symptom Checklist score, and Harris score within 6 months of surgery of 120 elderly patients with FNF who underwent total hip arthroplasty were collected. We analyzed the indicators of poor short-term postoperative prognosis and the ability of the indicators to predict poor prognosis and compared the correlation between the indicators and the Harris score. RESULTS: Anxiety, depression, garden classification of FNF, cause of fracture, FNF reduction quality, and length of hospital stay were independent influencing factors for poor short-term postoperative prognoses in elderly patients with FNF (P < 0.05). The areas under the curve for anxiety, depression, and length of hospital stay were 0.742, 0.854, and 0.749, respectively. The sensitivities of anxiety, depression, garden classification of FNF, and prediction of the cause of fracture were 0.857, 0.786, 0.821, and 0.821, respectively. The specificities of depression, FNF quality reduction, and length of hospital stay were the highest at 0.880, 0.783, and 0.761, respectively. Anxiety, depression, and somatization scores correlated moderately with Harris scores (r = -0.523, -0.625, and -0.554; all P < 0.001). CONCLUSION: Preoperative anxiety, depression, and somatization are correlated with poor short-term prognosis in elderly patients with FNF and warrant consideration.

13.
Plants (Basel) ; 13(13)2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38999713

RESUMEN

Detailed anatomical features of bark are used and interpreted in plant taxonomy, phylogenetics, and other areas of plant science. However, the delicate nature of bark cells, combined with the difficulty of obtaining high-quality sections and reliable data, limits the potential for utilizing and processing bark. In this study, the anatomical structure of the bark of 10 Quercus species growing in Yunnan Province, China, was characterized in detail. The results indicate that the anatomical features of the barks of 10 Quercus spp. show a certain degree of consistency. Specifically, sieve tubes are distributed in solitary elements or in small groups, mostly as compound sieve plates containing 2-8 sieve areas, suggesting that Quercus spp. may occupy a conservative evolutionary position. Additionally, for the first time, this study reports the presence of simple sieve plates in the sieve tube elements of Quercus phloem. Each sieve tube element has a companion cell on one side. The companion cell strands contain 2-7 cells. Axial parenchyma is diffuse, with parenchyma strands typically consisting of 4-7 cells; druses are present within chambered crystalliferous cells. Phloem rays are of two distinct sizes and often exhibit dilatation and sclerification, and the ray composition consists of procumbent cells. Sclerenchyma is composed of fibers and sclereids, both of which contain prismatic crystals. Most of the fibers are gelatinous fibers, which are distributed in discontinuous tangential bands of about five cells in width. Sclereids appear in clusters. The presence of sclerenchyma provides mechanical support to the bark, reducing the collapse of the phloem. Periderm usually consists of around 10-30 layers of phellem, and Quercus acutissima and Q. variabilis can reach dozens or hundreds layers. The phelloderm typically consists of from two to five layers, with Q. variabilis having up to ten or more layers. The filling tissue of lenticels in all Quercus species is nonstratified (homogeneous) and largely nonsuberized. Overall, this study enriches our comprehension of Quercus bark anatomy, elucidating evolutionary patterns, functional adaptations, and ecological ramifications within this significant botanical genus.

14.
ACS Appl Mater Interfaces ; 16(28): 36063-36076, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38958208

RESUMEN

The cell membrane separates the intracellular compartment from the extracellular environment, constraining exogenous molecules to enter the cell. Conventional electroporation typically employs high-voltage and short-duration pulses to facilitate the transmembrane transport of molecules impermeable to the membrane under natural conditions by creating temporary hydrophilic pores on the membrane. Electroporation not only enables the entry of exogenous molecules but also directs the intracellular distribution of the electric field. Recent advancements have markedly enhanced the efficiency of intracellular molecule delivery, achieved through the utilization of microstructures, microelectrodes, and surface modifications. However, little attention is paid to regulating the motion of molecules during and after passing through the membrane to improve delivery efficiency, resulting in an unsatisfactory delivery efficiency and high dose demand. Here, we proposed the strategy of regulating the motion of charged molecules during the delivery process by progressive electroporation (PEP), utilizing modulated electric fields. Efficient delivery of charged molecules with an expanded distribution and increased accumulation by PEP was demonstrated through numerical simulations and experimental results. The dose demand can be reduced by 10-40% depending on the size and charge of the molecules. We confirmed the safety of PEP for intracellular delivery in both short and long terms through cytotoxicity assays and transcriptome analysis. Overall, this work not only reveals the mechanism and effectiveness of PEP-enhanced intracellular delivery of charged molecules but also suggests the potential integration of field manipulation of molecular motion with surface modification techniques for biomedical applications such as cell engineering and sensitive cellular monitoring.


Asunto(s)
Electroporación , Electroporación/métodos , Humanos , Membrana Celular/metabolismo
15.
bioRxiv ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-38915596

RESUMEN

Hypothalamic kisspeptin (Kiss1) neurons are vital for pubertal development and reproduction. Arcuate nucleus Kiss1 (Kiss1ARH) neurons are responsible for the pulsatile release of Gonadotropin-releasing Hormone (GnRH). In females, the behavior of Kiss1ARH neurons, expressing Kiss1, Neurokinin B (NKB), and Dynorphin (Dyn), varies throughout the ovarian cycle. Studies indicate that 17ß-estradiol (E2) reduces peptide expression but increases Vglut2 mRNA and glutamate neurotransmission in these neurons, suggesting a shift from peptidergic to glutamatergic signaling. To investigate this shift, we combined transcriptomics, electrophysiology, and mathematical modeling. Our results demonstrate that E2 treatment upregulates the mRNA expression of voltage-activated calcium channels, elevating the whole-cell calcium current and that contribute to high-frequency burst firing. Additionally, E2 treatment decreased the mRNA levels of Canonical Transient Receptor Potential (TPRC) 5 and G protein-coupled K+ (GIRK) channels. When TRPC5 channels in Kiss1ARH neurons were deleted using CRISPR, the slow excitatory postsynaptic potential (sEPSP) was eliminated. Our data enabled us to formulate a biophysically realistic mathematical model of the Kiss1ARH neuron, suggesting that E2 modifies ionic conductances in Kiss1ARH neurons, enabling the transition from high frequency synchronous firing through NKB-driven activation of TRPC5 channels to a short bursting mode facilitating glutamate release. In a low E2 milieu, synchronous firing of Kiss1ARH neurons drives pulsatile release of GnRH, while the transition to burst firing with high, preovulatory levels of E2 would facilitate the GnRH surge through its glutamatergic synaptic connection to preoptic Kiss1 neurons.

16.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 611-618, 2024 Jun 15.
Artículo en Chino | MEDLINE | ID: mdl-38926378

RESUMEN

OBJECTIVES: To investigate the risk factors for bronchopulmonary dysplasia (BPD) in twin preterm infants with a gestational age of <34 weeks, and to provide a basis for early identification of BPD in twin preterm infants in clinical practice. METHODS: A retrospective analysis was performed for the twin preterm infants with a gestational age of <34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020. According to their conditions, they were divided into group A (both twins had BPD), group B (only one twin had BPD), and group C (neither twin had BPD). The risk factors for BPD in twin preterm infants were analyzed. Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins. RESULTS: A total of 904 pairs of twins with a gestational age of <34 weeks were included in this study. The multivariate logistic regression analysis showed that compared with group C, birth weight discordance of >25% between the twins was an independent risk factor for BPD in one of the twins (OR=3.370, 95%CI: 1.500-7.568, P<0.05), and high gestational age at birth was a protective factor against BPD (P<0.05). The conditional logistic regression analysis of group B showed that small-for-gestational-age (SGA) birth was an independent risk factor for BPD in individual twins (OR=5.017, 95%CI: 1.040-24.190, P<0.05). CONCLUSIONS: The development of BPD in twin preterm infants is associated with gestational age, birth weight discordance between the twins, and SGA birth.


Asunto(s)
Displasia Broncopulmonar , Recien Nacido Prematuro , Gemelos , Humanos , Displasia Broncopulmonar/etiología , Displasia Broncopulmonar/epidemiología , Factores de Riesgo , Recién Nacido , Femenino , Estudios Retrospectivos , Masculino , Edad Gestacional , Peso al Nacer , Modelos Logísticos
17.
J Hazard Mater ; 475: 134869, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38870857

RESUMEN

Photoreduction of highly toxic U(VI) to less toxic U(IV) is crucial for mitigating radioactive contamination. Herein, a CoWO4/TpDD p-n heterojunction is synthesized, with TpDD serving as the n-type semiconductor substrate and CoWO4 as the p-type semiconductor grown in situ on its surface. The Fermi energy difference between TpDD and CoWO4 provides the electrochemical potential for charge-hole separation. Moreover, the Coulombic forces from the distinct carrier types between the two materials synergistically facilitate the transfer of electrons and holes. Hence, an internal electric field directed from TpDD to CoWO4 is established. Under photoexcitation conditions, charges and holes migrate efficiently along the curved band and internal electric field, further enhancing charge-hole separation. As a result, the removal capacity of CoWO4/TpDD increases from 515.2 mg/g in the dark to 1754.6 mg/g under light conditions. Thus, constructing a p-n heterojunction proves to be an effective strategy for remediating uranium-contaminated environments.

18.
Inorg Chem ; 63(24): 11459-11469, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38842950

RESUMEN

The performance of covalent-organic frameworks (COFs) for the photocatalytic extraction of uranium is greatly limited by the number of adsorption sites. Herein, inspired by electronegative redox reactions, we designed a nitrogen-oxygen rich pyrazine connected COF (TQY-COF) with multiple redox sites as a platform for extracting uranium via combining superaffinity and enhanced photoinduction. The preorganized bisnitrogen-bisoxygen donor configuration on TQY-COF is entirely matched with the typical geometric coordination of hexavalent uranyl ions, which demonstrates high affinity (tetra-coordination). In addition, the presence of the carbonyl group and pyrazine ring effectively stores and controls electron flow, which efficaciously facilitates the separation of e-/h+ and enhances photocatalytic performance. The experimental results show that TQY-COF removes up to 99.8% of uranyl ions from actual uranium mine wastewater under the light conditions without a sacrificial agent, and the separation coefficient reaches 1.73 × 106 mL g-1 in the presence of multiple metal ions, which realizes the precise separation in the complex environment. Importantly, DFT calculations further elucidate the coordination mechanism of uranium and demonstrate the necessity of the presence of N/O atoms in the photocatalytic adsorption of uranium.

19.
Appl Opt ; 63(12): 3228-3236, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38856471

RESUMEN

Due to its numerous advantages such as high gain and low operating bias, the silicon photomultiplier (SiPM) holds great potential in LiDAR applications. However, it is more jittery at weak echoes and more sensitive to ambient light, making its ranging performance at low signal-to-noise ratios (SNRs) severely deteriorated. To enhance the ranging performance of SiPM LiDAR under low SNR, a novel echo processing method, to the best of our knowledge, was proposed based on the statistical property of SiPM responses and validated under relatively intensive sunlight (>50k l x) using a self-developed LiDAR system. At the same time, laser pulse width modulation and multi-pulse laser emission are used in ranging experiments to maximize the advantages of this method. It has shown that increasing the laser pulse width within a certain range can improve ranging performance, and that emitting multiple laser pulses improves ranging performance more significantly. Utilizing a three-pulse laser with a peak power of only 3.2 W, a target 122 m away was ranged with a precision of 6.53 cm with only five accumulations.

20.
Waste Manag ; 183: 191-198, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38761483

RESUMEN

With the development of municipal solid waste incineration technologies, the disposal of fly ash has become a difficult problem that many countries need to solve. High-temperature melting is a promising disposal technology. Based on this, a new process for collaborative treatment of fly ash in metallurgical blast furnaces had been proposed in this study. To explore the impact of disposal of fly ash on blast furnace production, by simulating the high-temperature reducing environment of blast furnaces, the melting changes of water-washed fly ash (W-FA), and the effects of W-FA injection on coal combustion and products (slag, iron) composition were studied. The results showed that W-FA, as a flux, could be sprayed into the blast furnace separately or mixed with coal. But when injected along with coal, W-FA would suppress the combustion of coal. After melting, the removal rates of S, P, Cl, and Pb in W-FA were 21%, 30%, 86%, and 89%, respectively. The removal rates of K, Na, and Zn were close to 100%, and Cr was basically not removed. When the proportion of W-FA to coal was less than 1%, in addition to controlling the alkalinity of the slag, the impact of W-FA on the composition of iron and slag was minimal. The successful execution of this work will not only achieve the reduction, harmless and resourceful utilization of fly ash, but also save investment and operating costs of disposal facilities, with both environmental and social benefits.


Asunto(s)
Ceniza del Carbón , Incineración , Eliminación de Residuos , Residuos Sólidos , Ceniza del Carbón/química , Incineración/métodos , Residuos Sólidos/análisis , Eliminación de Residuos/métodos , Calor , Carbón Mineral
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