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1.
Org Lett ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39172514

RESUMEN

A novel photoredox/nickel dual catalytic intermolecular alkylarylation of vinylarenes with tertiary and secondary alkyltrifluoroborates and aryl bromides is described, which affords 1,1-diarylalkane frameworks that are found in various natural products as well as functionalized molecules in good to excellent yield and regioselectivity through a radical relay process. Notably, this redox-neutral reaction could proceed efficiently with good tolerance of various substrates, including a great diversity of commercially available (hetero)aryl bromides, alkyltrifluoroborates, and vinylarenes.

2.
J Environ Manage ; 366: 121830, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39013316

RESUMEN

The rapid expansion of laver (Porphyra yezoensis) cultivation on lower tidal flats has become integral to the local economy, yet it also raises concerns regarding its potential impact on the morphological evolution due to increasing human activities. This study utilizes integrated near-bed field measurements to assess morphological dynamics and quantify sediment erosion processes, highlighting the significant impact of laver harvest on tidal flat stability. Our results show that erosion and bed coarsening in the cultivated areas experienced a notable intensification immediately after harvest, with net erosion in cultivated areas reaching approximately -38.2 mm during the first tide post-harvest, markedly higher-more than an order of magnitude-compared to adjacent uncultivated areas. The erosion rate notably spiked with the average bed level change rate increasing to -13.8 × 10-4 mm/s, compared to a rate of +0.3 × 10-4 mm/s during the unharvest period. Subsequently, the cultivated areas entered a recovery phase with a deposition amount of +12.5 mm, while the net cumulative erosion thickness throughout the entire observation period was -25.2 mm. The cultivation method, characterized by consistent harvests every 10 days, means that even minor erosion from continuous harvests can escalate into significant degradation. This study suggests that long-term cultivation cycle practices may result in irreversible changes to the depositional environment, potentially jeopardizing the habitat viability and ecological function. Sustainable agricultural strategies, including site selection, infrastructure planning, monitoring environmental changes, ecological assessments and sustainable practices, are recommended to mitigate the negative impacts of cultivation on regional stability and preserve the coastal ecological balance.


Asunto(s)
Conservación de los Recursos Naturales , Algas Comestibles , Monitoreo del Ambiente , Sedimentos Geológicos , Porphyra , Erosión del Suelo
3.
Toxicon ; 247: 107822, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-38908528

RESUMEN

To date there are only pirfenidone (PFD) and nintedanib to be given conditional recommendation in idiopathic pulmonary fibrosis (IPF) therapies with slowing disease progression, but neither has prospectively shown a reduced mortality. It is one of the urgent topics to find effective drugs for pulmonary fibrosis in medicine. Previous studies have demonstrated that microcystin-RR (MC-RR) effectively alleviates bleomycin-induced pulmonary fibrosis, but the mechanism has not been fully elucidated yet. We further conducted a comparison of therapeutic effect on the model animals of pulmonary fibrosis between MC-RR and PFD with histopathology and the expression of the molecular markers involved in differentiation, proliferation and metabolism of myofibroblasts, a major effector cell of tissue fibrosis. The levels of the enzyme molecules for maintaining the stability of interstitial structure were also evaluated. Our results showed that MC-RR and PFD effectively alleviated pulmonary fibrosis in model mice with a decreased signaling and marker molecules associated with myofibroblast differentiation and lung fibrotic lesion. In the meantime, both MC-RR and PFD treatment are beneficial to restore molecular dynamics of interstitial tissue and maintain the stability of interstitial architecture. Unexpectedly, MC-RR, rather than PFD, showed a significant effect on inhibiting PKM2-HIF-1α signaling and reducing the level of p-STAT3. Additionally, MC-RR showed a better inhibition effect on FGFR1 expression. Given that PKM2-HIF-1α and activated STAT3 molecular present a critical role in promoting the proliferation of myofibroblasts, MC-RR as a new strategy for IPF treatment has potential advantage over PFD.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia , Microcistinas , Fibrosis Pulmonar , Piridonas , Animales , Microcistinas/toxicidad , Ratones , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/inducido químicamente , Piridonas/farmacología , Piridonas/uso terapéutico , Bleomicina , Transducción de Señal/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Miofibroblastos/efectos de los fármacos , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Masculino , Modelos Animales de Enfermedad , Piruvato Quinasa
4.
World J Stem Cells ; 16(4): 444-458, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38690512

RESUMEN

BACKGROUND: Leukemia stem cells (LSCs) are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia (AML), as they are protected by the bone marrow microenvironment (BMM) against conventional therapies. Gossypol acetic acid (GAA), which is extracted from the seeds of cotton plants, exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2. AIM: To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism. METHODS: In this study, LSCs were magnetically sorted from AML cell lines and the CD34+CD38- population was obtained. The expression of leucine-rich pentatricopeptide repeat-containing protein (LRPPRC) and forkhead box M1 (FOXM1) was evaluated in LSCs, and the effects of GAA on malignancies and mitochondrial function were measured. RESULTS: LRPPRC was found to be upregulated, and GAA inhibited cell proliferation by degrading LRPPRC. GAA induced LRPPRC degradation and inhibited the activation of interleukin 6 (IL-6)/janus kinase (JAK) 1/signal transducer and activator of transcription (STAT) 3 signaling, enhancing chemosensitivity in LSCs against conventional chemotherapies, including L-Asparaginase, Dexamethasone, and cytarabine. GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC. Furthermore, GAA induced reactive oxygen species accumulation, disturbed mitochondrial homeostasis, and caused mitochondrial dysfunction. By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC, GAA resulted in the elimination of LSCs. Meanwhile, GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage. CONCLUSION: Taken together, the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML.

5.
Sci Adv ; 10(18): eadk1698, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38701206

RESUMEN

Deltas are threatened by erosion due to climate change and reduced sediment supply, but their response to these changes remains poorly quantified. We investigate the abandoned Yellow River delta that has transitioned from rapid growth to ongoing deterioration due to a river avulsion removing the sediment supply. Integrating bathymetric data, process observations, and sediment transport modeling, we find that while the subaerial delta was stabilized by engineering measures, the subaqueous delta continued to erode due to intensified storms, losing 39% of its mass deposited before the avulsion. Long-term observations show that winter storms initiate scouring of the subaqueous delta, contributing up to 70% of seabed erosion. We then analyze 108 global deltas to assess subaqueous delta erosion risks and identify 17 deltas facing similar situations of sediment decline and storm intensification during the past 40 years. Our findings suggest that subaqueous delta erosion must be integrated into delta sustainability evaluations.

6.
J Gastrointest Surg ; 28(8): 1223-1228, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38705366

RESUMEN

BACKGROUND: This study presented an innovative technique in totally laparoscopic total gastrectomy (TLTG) for overlap esophagojejunostomy (E-J), termed self-pulling and latter transection (SPLT) (overlap SPLT). It evaluated the effectiveness and short-term outcomes of this novel method through a comparative analysis with the established functional end-to-end (FETE) E-J incorporating SPLT. METHODS: From September 2018 to September 2023, this study enrolled 68 patients with gastric cancer who underwent TLTG with overlap SPLT anastomosis and 120 patients who underwent TLTG with FETE SPLT anastomosis. Clinicopathologic characteristics and surgical and postoperative outcomes data for overlap SPLT cases were gathered and retrospectively compared with those from FETE SPLT TLTG to evaluate the effectiveness and clinical safety. RESULTS: The duration of anastomosis for overlap SPLT was 25.3 ± 7.4 minutes, significantly longer than that for the FETE SPLT (18.1 ± 4.0 minutes, P = .031). Perioperatively, 1 anastomosis-related complication occurred in each group, but this did not constitute a statistically significant difference (P = .682). No statistically significant differences were found between the 2 groups in terms of operative time, postoperative hospital stay, operative cost, surgical margins, or number of lymph nodes removed. Postoperative morbidity rates were similar between the groups (4.4% vs 5.8%, P = .676). CONCLUSION: The overlap SPLT technique is regarded as a safe and feasible method for anastomosis. There were no apparent differences in complications between overlap SPLT and FETE SPLT, but overlap SPLT costed 1 additional stapler cartridge and required a longer duration.


Asunto(s)
Anastomosis Quirúrgica , Estudios de Factibilidad , Gastrectomía , Laparoscopía , Tempo Operativo , Neoplasias Gástricas , Humanos , Gastrectomía/métodos , Gastrectomía/efectos adversos , Femenino , Laparoscopía/métodos , Laparoscopía/efectos adversos , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/cirugía , Estudios Retrospectivos , Anciano , Anastomosis Quirúrgica/métodos , Anastomosis Quirúrgica/efectos adversos , Esófago/cirugía , Yeyuno/cirugía , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología
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