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Small molecule donors (SMDs) play subtle roles in the signaling mechanism and disease treatments. While many excellent SMDs have been developed, dosage control, targeted delivery, spatiotemporal feedback, as well as the efficiency evaluation of small molecules are still key challenges. Accordingly, fluorescent small molecule donors (FSMDs) have emerged to meet these challenges. FSMDs enable controllable release and non-invasive real-time monitoring, providing significant advantages for drug development and clinical diagnosis. Integration of FSMDs with chemotherapeutic, photodynamic or photothermal properties can take full advantage of each mode to enhance therapeutic efficacy. Given the remarkable properties and the thriving development of FSMDs, we believe a review is needed to summarize the design, triggering strategies and tracking mechanisms of FSMDs. With this review, we compiled FSMDs for most small molecules (nitric oxide, carbon monoxide, hydrogen sulfide, sulfur dioxide, reactive oxygen species and formaldehyde), and discuss recent progress concerning their molecular design, structural classification, mechanisms of generation, triggered release, structure-activity relationships, and the fluorescence response mechanism. Firstly, from the large number of fluorescent small molecular donors available, we have organized the common structures for producing different types of small molecules, providing a general strategy for the development of FSMDs. Secondly, we have classified FSMDs in terms of the respective donor types and fluorophore structures. Thirdly, we discuss the mechanisms and factors associated with the controlled release of small molecules and the regulation of the fluorescence responses, from which universal guidelines for optical properties and structure rearrangement were established, mainly involving light-controlled, enzyme-activated, reactive oxygen species-triggered, biothiol-triggered, single-electron reduction, click chemistry, and other triggering mechanisms. Fourthly, representative applications of FSMDs for trackable release, and evaluation monitoring, as well as for visible in vivo treatment are outlined, to illustrate the potential of FSMDs in drug screening and precision medicine. Finally, we discuss the opportunities and remaining challenges for the development of FSMDs for practical and clinical applications, which we anticipate will stimulate the attention of researchers in the diverse fields of chemistry, pharmacology, chemical biology and clinical chemistry. With this review, we hope to impart new understanding thereby enabling the rapid development of the next generation of FSMDs.
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Colorantes Fluorescentes , Bibliotecas de Moléculas Pequeñas , Humanos , Colorantes Fluorescentes/química , Bibliotecas de Moléculas Pequeñas/química , Especies Reactivas de Oxígeno/metabolismo , Animales , Monóxido de Carbono/química , Monóxido de Carbono/metabolismoRESUMEN
Polycyclic hydrocarbons with diradical and polyradical characters usually display unique reactivities in ring-cyclization reactions. However, such reactions are rarely used to construct π-extended polycyclic aromatic hydrocarbons. Here, we describe the synthesis of an S-shaped doubly helical singlet diradicaloid compound and its facile transformation into an unprecedented circumchrysene via a two-stage ring cyclization, which includes: (1) an eletrocylization from diradicaloid precursor and (2) a Scholl reaction. The reaction mechanism was investigated through in situ spectroscopic studies, assisted by theoretical calculations. This reaction sequence yields an optically resolved π-extended [5]helicene derivative with a fluorescence quantum yield up to 85% and a circularly polarized luminescence brightness up to 6.05 M-1 cm-1 in the far-red to near-infrared regions. This sequence also yielded a highly delocalized circumchrysene molecule, exhibiting large electron delocalization, moderate fluorescence quantum yield, and multistage redox properties.
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As the main active glycoprotein of egg white, the biological functions of chicken ovomucin α- and ß-subunit are closely related to the structure of glycans. However, the exact composition and structure of the subunit glycans are still unknown. We obtained highly pure chicken ovomucin α-subunit and ß-subunit protein bands by the strategy combined with two-step isoelectric precipitation and SDS-PAGE gel electrophoresis. The ammonia-catalyzed one-pot procedure was then used to release and capture α-and ß-subunit protein glycans with 1-phenyl- 3-Methyl-5-pyrazolone (PMP). The N/O-glycans of bis-PMP derivatives were purified and analyzed by LC-MS. More importantly, an effective dual modification was performed to accurately quantify neutral and sialylated O-glycans through methylamidation of sialic acid residues and simultaneously through carbonyl condensation reactions of reducing ends with PMP. We first showed that the α-subunit protein has only N-glycosylation modification, and the ß-subunit only O-glycosylation, a total of 22 N-glycans and 20 O-glycans were identified in the α- and ß-subunit, respectively. In addition, the complex N-glycan (47 %) and the sialylated O-glycan (77 %) are each major types of the above subunits. Such findings in this study provide a basis for studying the functional and biological activities of chicken ovomucin glycans.
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Pollos , Electroforesis en Gel de Poliacrilamida , Ovomucina , Polisacáridos , Animales , Glicosilación , Cromatografía Líquida con Espectrometría de Masas , Ovomucina/química , Polisacáridos/química , Polisacáridos/análisis , Subunidades de Proteína/químicaRESUMEN
Chemokines and chemokine receptors are indispensable to play a key role in the development of malignant tumors. As one of the most widely expressed chemokine receptors, chemokine (C-X-C motif) receptor 4 (CXCR4) has been a popular research focus. In most tumors, CXCR4 expression is significantly upregulated. Moreover, integrated nuclide diagnosis and therapy targeting CXCR4 show great potential. [68Ga]Ga-pentixafor, a radioligand targeting CXCR4, exhibits a strong affinity for CXCR4 both in vivo and in vitro. However, [177Lu]Lu-pentixather, the therapeutic companion of [68Ga]Ga-pentixafor, requires significant refinement to mitigate its pronounced hepatic biodistribution. The objective of this study was to synthesize theranostic molecular tracers with superior CXCR4 targeting functions. The Daudi cell line, which highly expressed CXCR4, and the MM.1S cell line, which weakly expressed CXCR4, were used in this study. Based on the pharmacophore cyclo (-d-Tyr-n-me-d-Orn-l-Arg-L-2-NAL-Gly-) (CPCR4) of pentixafor, six tracers were synthesized: [124I]I-1 ([124I]I-CPCR4), [99mTc]Tc-2 ([99mTc]Tc-HYNIC-CPCR4), [124I]I-3 ([124I]I-pentixafor), [18F]AlF-4 ([18F]AlF-NETA-CPCR4), [99mTc]Tc-5 ([99mTc]Tc-MAG3-CPCR4) and [124I]I-6 ([124I]I-pentixafor-Ga) and their radiochemical purities were all higher than 95%. After positron emission tomography (PET)/single-photon emission computed tomography (SPECT) imaging, the [124I]I-6 group exhibited the best target-nontarget ratio. At the same time, comparing the [68Ga]Ga-pentixafor group with the [124I]I-6 group, we found that the [124I]I-6 group had a better target-nontarget ratio and lower uptake in nontarget organs. Therefore, compound 6 was selected for therapeutic radionuclide (131I) labeling, and the tumor-bearing animal models were treated with [131I]I-6. The volume of the tumor site was significantly reduced in the treatment group compared with the control group, and no significant side effects were found. [124I]I-6 and [131I]I-6 showed excellent affinity for targeting CXCR4, and they showed great potential for the integrated diagnosis and treatment of tumors with high CXCR4 expression.
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Complejos de Coordinación , Receptores CXCR4 , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Animales , Humanos , Ratones , Línea Celular Tumoral , Distribución Tisular , Radiofármacos/farmacocinética , Radiofármacos/farmacología , Radiofármacos/química , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Radioisótopos de Galio , Ratones Desnudos , Nanomedicina Teranóstica/métodos , FemeninoRESUMEN
Claudin18.2 (CLDN18.2), due to its high expression in various gastric cancer tissues, is considered an optimal target for antitumor drug molecules. In this study, we obtained the labeled compounds of [125I]I-zolbetuximab using the Iodogen method. Under the optimum labeling conditions, the molar activity of [125I]I-zolbetuximab was 1.75 × 102 GBq/µmol, and the labeling efficiency was more than 99%. The labeled compounds exhibited excellent in vitro stability in both phosphate buffer saline (PBS, pH = 7.4) and fetal bovine serum systems (FBS) (radiochemical purity >90% at 72 h). The uptake percentage of [125I]I-zolbetuximab in MKN45-CLDN18.2 cells is 24.69 ± 0.84% after 6 h. The saturation binding assay and specificity assay further demonstrated the high specificity of [125I]I-zolbetuximab for CLDN18.2. The long retention at the tumor site and rapid metabolic clearance at other organ sites of [125I]I-zolbetuximab were observed in small-animal SPECT-CT imaging. The same trend was also observed in the biodistribution study. Due to the excellent targeting ability of zolbetuximab for CLDN18.2, [125I]I-zolbetuximab exhibits strong specific binding and retention with cells and tumors highly expressing CLDN18.2. However, the balance between mAb's longer cycle time in vivo and targeting binding and retention ability should be intensively considered for using this kind of radiopharmaceutical in the diagnosis and treatment of CLDN18.2-positive gastric cancer.
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Claudinas , Animales , Humanos , Ratones , Distribución Tisular , Línea Celular Tumoral , Claudinas/metabolismo , Radioisótopos de Yodo , Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Radiofármacos/farmacocinética , Radiofármacos/química , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones Endogámicos BALB C , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/química , Femenino , Masculino , RatasRESUMEN
A series of novel near-infrared (NIR) xanthene-chalcone fluorophores were constructed through a modular synthesis with the electron-donating xanthene moiety and the electron-withdrawing chalcone moiety. These fluorophores are convenient for fluorescence imaging in living cells, benefiting from their NIR emissions (650-710 nm), large Stokes shifts (>100 nm), moderate quantum yields and low cytotoxicity. The substituted hydroxyl group of the xanthene-chalcone fluorophore HCA-E facilitates the development of multifunctional fluorescent probes. As an example, a highly sensitive and selective probe N-HCA-E for glutathione (GSH) detection was developed based on the fluorophore HCA-E. A 4-nitrobenzenesulfonyl (4-Ns) group was introduced to cage the hydroxyl group of HCA-E, which was used as a selective recognition site for the thiol of GSH and an effective fluorescence quencher. Probe N-HCA-E revealed NIR "turn-on" fluorescence (709 nm) for endogenous and exogenous GSH detection in lysosomes with a large Stokes shift (129 nm) and high anti-interference ability.
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Colorantes Fluorescentes , Glutatión , Imagen Óptica , Xantenos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/toxicidad , Colorantes Fluorescentes/síntesis química , Xantenos/química , Humanos , Glutatión/química , Imagen Óptica/métodos , Chalconas/química , Células HeLa , Lisosomas/química , Lisosomas/metabolismo , Rayos Infrarrojos , Chalcona/químicaRESUMEN
Irinotecan (CPT-11) is a widely utilized topoisomerase I inhibitor in the treatment of colorectal cancer and other malignant tumors. However, severe and even life-threatening dose-limiting toxicity-delayed diarrhea affects the clinical application of CPT-11. The standard treatment for CPT-11-induced delayed diarrhea is prompt use of loperamide (LPA), however LPA can also cause constipation, diarrhea and even intestinal obstruction and has a high failure rate. Carboxylesterase 2 (CES2) is the main enzyme in the intestinal transformation of CPT-11, which can convert CPT-11 into toxic metabolite SN-38 and produce intestinal toxicity. Inhibiting CES2 activity can block the hydrolysis process of CPT-11 in the intestine and reduce SN-38 accumulation. Additionally, Farnesoid X receptor (FXR) agonists have anti-inflammatory, anti-secretory, and protective functions on intestinal barrier integrity that could potentially alleviate diarrhea. In this study, we investigated for the first time the anti-delayed diarrhea effect of FXR agonists, and the first time identified LE-77 as a potent dual modulator that activates FXR and inhibits CES2 through high-throughput screening. In the CPT-11-induced delayed diarrhea model, LE-77 demonstrated a dual modulator mechanism by activating FXR and inhibiting CES2, thereby reducing the accumulation of SN-38 in the intestine, alleviating intestinal inflammation, preserving intestinal mucosal integrity, and ultimately alleviating delayed diarrhea.
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Epimedium [Epimedium sagittatum (Sieb. et Zucc.) Maxim., E. brevicornu Maxim., E. pubescens Maxim., E. koreanum Nakai] plants are perennial herbs and the dry leaves were used in traditional Chinese medicine with different medicinal effects (Chinese Pharmacopoeia, 2020 edition). In early August 2022 (the high temperature was 33 â and the low temperature was 25 â on average with above 70% relative humidity), large necrotized leaf spots were initially observed in one-year and two-year old E. sagittatum plants in Dengzhou (32°35'26.84" N, 112°11'8.37" E), Henan province, China. White mycelia, yellow and brown sclerotia were observed along the petioles and colonized to the back of leaves and also on soil-petioles interface around the diseased Epimedium plants. White mycelia spread rapidly from the disease plants as a center to neighboring plants and the infected plants eventually wilted. The disease incidence was 16.0% and 28.0% in the surveyed cultivation fields in Dengzhou (Henan) and Danjiangkou (Hubei), respectively, which resulted in above 20% of yield loss. The symptomatic tissues (petioles, n≥10) were cut into 0.5 cm sections with autoclaved scissors and surface sterilized with 75% ethanol for 30 s, followed by 3 min in 1% NaClO, rinsed three times with distilled sterile water, plated on autoclaved filter paper to remove excess moisture in a biological laminar hood, transferred onto potato dextrose agar (PDA) plates and incubated at 28â in incubator in the dark for 3-5 days. Twelve fungal isolates with white radial colony morphology were obtained and purified by hyphal-tip method. The isolates formed radial colonies showing abundant aerial mycelia with a growth rate of 19.25 to 22.25 mm/day (mean = 21.67 ± 0.77 mm; n = 36) and white abundant sclerotia were observed after 5-7 days post inoculation at 28â. The hyphae of the isolates were hyaline, branched with clamp connections at septa. The isolates formed dark brown sclerotia on PDA plate post 10-14 days incubation. The diameter of mature brown sclerotia ranged from 1.31 to 3.07 mm (mean = 1.91 ± 0.39 mm; n = 40) and 13 to 45 sclerotia (mean = 28; n = 24) were observed on each Petri dish. The isolates were tentatively identified as Agroathelia rolfsii based on morphological characteristics (Yi Y., et al. 2024) and isolate YYHBJ1 was selected as representative isolate for molecular identification and pathogenicity test. The genomic DNA was extracted using CTAB method. For molecular identification, ITS region, translation elongation factor-1alpha (TEF-1α) and nuclear large-subunit ribosomal DNA (nLSU-rDNA) were amplified (White et al. 1990, Wendland and Kothe, 1997). The sequences 684-bp ITS (OR428367), 534-bp TEF1α (OR485567), and 965-bp nLSU-rDNA (OR426612) of isolate YYHBJ1 were deposited in GenBank. Sequence analysis revealed that ITS, TEF1α and nLSU-rDNA sequences of YYHBJ001 showed 100%, 99.63%, and 100% identity to ITS (MN380242 and JF819727), EF1α (MN262527) and nLSU-rDNA (MT225781 and AY635773) sequences of Agroathelia rolfsii (Sacc.) Redhead & Mullineux (Redhead and Mullineux 2023). Pathogenicity tests was confirmed by inoculating 1 year-old E. sagittatum plants grown in pots with sterile soil. PDA plug (5 mm diameter) colonized with 3 brown sclerotia and the fungal culture which was cultivated for 12 days was deposited beside the petiole on the surface of the soil. The control plants were inoculated with PDA plugs without the pathogen. Five plants were used in each treatment. The plants were cultivated in incubator at 28â with 80% relative humidity. Fourteen days later, white mycelia growing out from the sclerotia and spread along the petioles to the leave and the infected leaves were yellow. After 21 to 24 days, all inoculated plants displayed symptoms like those observed in field, while no symptoms were observed on the controls. The fungus was re-isolated from the inoculated plants as described above, fulfilling Koch's postulates. The pathogenicity tests were repeated three times. Based on morphological feature and DNA sequences, the pathogen of southern blight on Epimedium plants was identified as A. rolfsii (anamorph S. rolfsii). The pathogen A. rolfsii usually infect kinds of crops and cause southern blight, such as peanuts, chili peppers, green onion and so on (Daunde et al. 2018). To our knowledge, this is the first report of A. rolfsii causing southern blight on E. sagittatum plants in Henan in China.
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The cultivated variety of Chinese yam (Dioscorea polystachya Turcz. cv. Tiegun) is an economically important plant, capable of producing tubers that are used as food and traditional Chinese medicine. The basal stem rot was found on approximately 65% of yam (tuber expansion stage) in a total of 10 ha field in Wuzhi, Wen, and Hua counties, Henan, China (Sep 2021). Dark brown fusiform lesions initially occurred at the stems basal, irregularly extending to join together and leading to loop-stem necrotic indentation. Three diseased samples from Wuzhi county were collected, cut into 5 × 5 mm pieces, surface sterilized in 75% ethanol (30 s) and 1% NaClO (1 min), washed in sterile water 3 times, and placed on PDA in the dark for 3 days at 28â. A total of 44 isolates forming three groups of Fusarium colonies were obtained using monosporic isolation, of which 19, 8, and 17 isolates were identified as F. oxysporum, F. solani, and F. proliferatum based on colony morphology, respectively. Typical isolates SYJJ6, 9, and 10 for each group were further studied. The SYJJ6 colonies showed gray white abundant fluffy aerial mycelium with rough edges, formation of ellipsoid, unicellular microconidia without septa, 5.6 to 13.4 × 2.4 to 4.7 µm (n = 50), and sickle-shaped, slightly curved macroconidia with 2 to 4 septa, 14.0 to 23.9 × 3.4 to 5.1 µm (n = 50). Isolate SYJJ9 produced flocculent white colonies, grew in a circular pattern with a sharp edge, forming oval or oblong microconidia with zero or one septum, 11.2 to 18.8 × 3.4 to 6.2 µm (n = 50), and slightly curved macroconidia with 2 to 3 septa, 27.6 to 44.0 × 3.9 to 7.4 µm (n = 50). SYJJ10 produced whitish or pinkish white colonies with fluffy aerial mycelium and a red pigmentation, produced renal or oval microconidia with no septa, 5.1 to 11.8 × 1.8 to 4.2 µm (n = 50), and falcate, slightly curved macroconidia with 3 to 4 septa, 16.1 to 30.2 × 3.1 to 5.9 µm (n = 50). Additionally, TUB, EF-1α, and RPB2 genes were amplified with primers BT2a/BT2b, EF1/EF2, and 5f2/-7cr, respectively (Glass and Donaldson 1995; O'Donnell et al. 1998, 2010). BLASTn analysis on SYJJ6 (OR047663, OR047666, OR047669), SYJJ9 (OR047665, OR047667, OR047670), and SYJJ10 (OR047664, OR047668, OR047671) gene sequences were over 99% identical to those of F. oxysporum (100%, MK432917; 100%, MN417196; 99.61%, MN457531), F. solani (100%, MF662662; 100%, MN223440; 99.80%, CP104055), and F. proliferatum (100%, ON557521; 100%, ON458137; 99.90%, LT841266), respectively. Pathogenicity tests of three isolates were separately performed on 60-day-old yam seedlings. The basal stems were wounded using needle, and the wounds were wrapped with cotton balls soaked with conidial suspension (1 mL, 3×106 conidia/mL) or water (control). Each isolate treated three plants and repeated three times. All plants were grown at 28â under a 16/8-h light/dark cycle. Typical symptoms emerged on basal stems at 16, 13, and 17 days after inoculation with the conidia of isolates SYJJ6, 9, and 10, while the control basal stems appeared healthy. The re-isolated fungi were identical to the original three isolates. Fusarium species (F. oxysporum, F. commune, F. humuli, etc.)were previously reported to cause wilt or stem rot on different D. polystachya cultivars (Fang et al. 2020; Li et al. 2023; Zhao et al. 2013), or basal stem rot on Panax ginseng (Ma et al. 2020). This is the first report of Chinese yam basal stem rot caused by Fusarium species, which threatens the production of Chinese yam 'Tiegun' and should be further studied.
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Programmed death-ligand 1 (PD-L1) expression is related to the efficacy and prognosis in triple-negative breast cancer. This study employed an indirect labeling method to synthesize [125I]PI-Atezolizumab. The in vitro stability of [125I]PI-Atezolizumab was assessed through incubation in phosphate buffered saline and fetal bovine serum, revealing sustained stability. Specific binding of [125I]PI-Atezolizumab to MDA-MB-231 cells expressing humanized PD-L1 was assessed through in vitro incubation, yielding a Kd value comparable to that of Atezolizumab. This suggests that the labeling process did not compromise the affinity of the Atezolizumab to PD-L1. Subsequently, pharmacokinetic studies were conducted in normal mice and biodistribution experiments in tumor-bearing mice. A comparison of the biodistribution results between [125I]PI-Atezolizumab and 125I-labeled Atezolizumab indicated better in vivo stability for the former. Single photon emission computed tomography (SPECT)/CT imaging further confirmed the targeted specificity of [125I]PI-Atezolizumab for PD-L1 in MDA-MB-231 xenografts, which were validated by immunohistochemistry staining. This research underscores the utility of [125I]PI-Atezolizumab, prepared via indirect labeling, for monitoring PD-L1 in triple-negative breast cancer models.
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OBJECTIVE: To examine the factors influencing hospital discharge readiness among Chinese patients who have undergone enterostomy. METHODS: In this descriptive, cross-sectional study, researchers recruited patients with colorectal cancer who underwent enterostomy at a tertiary hospital in Guangdong Province, China, via convenience sampling between January 2021 and January 2023. Participants completed the Readiness for Hospital Discharge Scale, Ostomy Self-care Ability Scale, and Stoma-Quality of Life-Chinese Questionnaire (Chinese version) at the time of hospital discharge. Univariate, correlation, and multiple linear regression analyses were performed to explore the impact of self-care ability, quality of life, and other clinicodemographic characteristics on patients' readiness for hospital discharge. RESULTS: Of the 200 questionnaires distributed, 177 (88.5%) were completed and included in the final analysis. The median scores for the factors considered in this study were as follows: Readiness for Hospital Discharge Scale was 148.00 (interquartile range [IQR], 117.50, 164.00), self-care intention of the Ostomy Self-care Ability Scale was 36.00 (IQR, 34.00, 40.00), self-care knowledge of the Ostomy Self-care Ability Scale was 17.00 (IQR, 15.00, 19.00), self-care skill of the Ostomy Self-care Ability Scale was 5.00 (IQR, 3.00, 6.00), and the total score for quality of life was 60.00 (IQR, 49.00, 69.00). Multiple linear regression analysis identified several key factors explaining 48.2% of the variance in global readiness for hospital discharge: global quality of life (ß = .347, P < .001), self-care knowledge (ß = .259, P < .001), leakage during hospitalization (ß = -0.241, P < .001), monthly family income (ß = .148, P = .008), stoma siting before surgery (ß = .130, P = .020), and self-care intention (ß = .127, P = .035). CONCLUSIONS: The readiness for hospital discharge among patients undergoing enterostomy in this study was high. Factors such as quality of life, self-care knowledge, leakage during hospitalization, monthly family income, stoma siting before surgery, and self-care intention after undergoing enterostomy influenced the patients' readiness for hospital discharge. Therefore, future studies should focus on developing interventions to enhance patients' readiness for hospital discharge.
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Enterostomía , Alta del Paciente , Calidad de Vida , Autocuidado , Humanos , Estudios Transversales , Masculino , Femenino , Persona de Mediana Edad , Anciano , Calidad de Vida/psicología , China , Encuestas y Cuestionarios , Autocuidado/métodos , Adulto , Neoplasias Colorrectales/cirugíaRESUMEN
We realized the microenvironment-differential Imaging of demethylated metabolites of methionine and the regional regulation of ferroptosis.
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Ferroptosis , Metionina , Fluorescencia , Racemetionina , Diagnóstico por Imagen , Microambiente TumoralRESUMEN
Density functional theory calculations were employed to investigate the Pd-catalyzed regio-selective hydroallylations of alkynes with allylborons: cooperation of Cu(OAc)2 and dppe resulting in 1,4-dienes while combination of AdCO2H and PCy3 leading to 1,5-dienes. A unified rationalization mechanism called "Lewis-acid-base-interaction promoted deprotonation/3,3-rearrangement" was proposed. Compared with the commonly reported metathesis pathway to only afford the metal-allyl intermediate, in the newly established mechanism, an additional Brønsted acid (as an initiator of the Pd0 oxidative addition) is generated by the interaction of the allylboron (Lewis acid) B atom with the nBuOH (Lewis base) O atom, and subsequent 3,3-rearrangement ensures the thermodynamic feasibility of the reaction. In addition, it was found that excess Cu(OAc)2 plays two potential roles in the oxidative addition/alkyne insertion: (i) the participation of one AcO- of Cu(OAc)2 ensures a large orbital overlap between the migrating H and Pd atoms, facilitating the formal AcO-H cleavage and (ii) the extra (OAc)2Cu···O(carboxyl) σ-coordination indirectly contributes to the (Me)C≡C(Ph) insertion into the Pd-H bond. Further analysis showed that the origin of the regioselectivity is closely related to the employed phosphorus ligand. These revealed results, which have been overlooked in the previous documents, would aid the development of new related catalytic reactions.
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Electroactive microbes can conduct extracellular electron transfer and have the potential to be applied as a bioresource to regulate soil geochemical properties and microbial communities. In this study, we incubated Fe-limited and Fe-enriched farmland soil together with electroactive microbes for 30 days; both soils were incubated with electroactive microbes and a common iron mineral, ferrihydrite. Our results indicated that the exogenous electroactive microbes decreased soil pH, total organic carbon (TOC), and total nitrogen (TN) but increased soil conductivity and promoted Fe(III) reduction. The addition of electroactive microbes also changed the soil microbial community from Firmicutes-dominated to Proteobacteria-dominated. Moreover, the total number of detected microbial species in the soil decreased from over 700 to less than 500. Importantly, the coexistence of N-transforming bacteria, Fe(III)-reducing bacteria and methanogens was also observed with the addition of electroactive microbes in Fe-rich soil, indicating the accelerated interspecies electron transfer of functional microflora.
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Compuestos Férricos , Microbiota , Suelo/química , Microbiología del Suelo , Minerales/química , Oxidación-ReducciónRESUMEN
Human carboxylesterase 2 (hCES2A), one of the most important serine hydrolases distributed in the small intestine and colon, plays a crucial role in the hydrolysis of various prodrugs and esters. Accumulating evidence has demonstrated that the inhibition of hCES2A effectively alleviate the side effects induced by some hCES2A-substrate drugs, including delayed diarrhea caused by the anticancer drug irinotecan. Nonetheless, there is a scarcity of selective and effective inhibitors that are suitable for irinotecan-induced delayed diarrhea. Following screening of the in-house library, the lead compound 01 was identified with potent inhibition on hCES2A, which was further optimized to obtain LK-44 with potent inhibitory activity (IC50 = 5.02 ± 0.67 µM) and high selectivity on hCES2A. Molecular docking and molecular dynamics simulations indicated that LK-44 can formed stable hydrogen bonds with amino acids surrounding the active cavity of hCES2A. The results of inhibition kinetics studies unveiled that LK-44 inhibited hCES2A-mediated FD hydrolysis in a mixed inhibition manner, with a Ki value of 5.28 µM. Notably, LK-44 exhibited low toxicity towards HepG2 cells according to the MTT assay. Importantly, in vivo studies showed that LK-44 significantly reduced the side effects of irinotecan-induced diarrhea. These findings suggested that LK-44 is a potent inhibitor of hCES2A with high selectivity against hCES1A, which has potential as a lead compound for the development of more effective hCES2A inhibitors to mitigate irinotecan-induced delayed diarrhea.
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Diarrea , Inhibidores Enzimáticos , Humanos , Diarrea/inducido químicamente , Diarrea/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Irinotecán/efectos adversos , Simulación del Acoplamiento Molecular , Simulación de Dinámica MolecularRESUMEN
Honeysuckle flower (Lonicera japonica Thunb.) is a traditional Chinese medicinal plant. It is perennial and widely cultivated in China, Japan and Korea. From late August to October in 2021 and 2022, leaf spots symptoms were observed on L. japonica in different planting fields in Yuzhou, Yuanyang and Fenqiu districts, Henan province, China. The disease incidence was above 85% which reduce photosynthesis. Early disease symptoms appeared as small, circular to elliptical, brown spots on the leaves and later the lesions (1 to 5 mm × 1 to 4 mm) slowly developed yellow haloes. The different brown lesions seldom merge and form larger irregular lesions. Small fragments (3 to 5 mm) of leave tissue were excised from the lesion margins and surface-sterilized in 3% NaClO for 3 min, followed by three washes with sterile distilled water, and then placed on potato dextrose agar (PDA) and incubated at 25°C in the dark for 5 days. A total number of 8 cultures were obtained and purified by single-spore subcultures on PDA for morphological identification. The colonies on PDA were whitish to gray, with cottony aerial mycelium. Conidiophores were fasciculate, olivaceous brown, straight or geniculate, uniform in width, multiseptate, and ranged from 290 to 700 µm (560 µm on average, n = 20). Conidia were hyaline, slightly curved or straight, needle shaped, truncate at the base, and terminal at the tip, 3 to 17-septate, and measuring 150 to 240 µm (180 µm on average, n = 20). The morphological features were consistent with Cercospora cf. flagellaris Ellis & G. Martin (Groenewald et al. 2013). The genomic DNA was extracted using CTAB method. The nuclear ribosomal internal transcribed spacer region (ITS), portions of the actin (ACT), histone H3 (HIS3), and translation elongation factor 1-α (TEF1) genes were amplified using primers ITS1/ITS4 (Groenewald et al. 2013), ACT-512F/ACT-783R (Carbone and Kohn 1999), CYLH3F/CYLH3R (Crous et al. 2006), and EF1-728F/EF1-986R (Carbone and Kohn 1999). The resulting 537-bp ITS, 226-bp ACT, 410-bp HIS3, and 306-bp TEF1 sequences of isolate JDJ002 were deposited in GenBank (accession nos. OR492367, OR548247, OR548248 and OR548248, respectively). Sequence analysis revealed that ITS, ACT, HIS3 and TEF1α sequences exhibited ≥99% of identity with the ITS (KP896013), ACT(KP895965), HIS3(MK991295) and TEF1 (MN180408) sequences of C. cf. flagellaris, respectively. A pathogenicity test was conducted on healthy of L. japonica leaves. The healthy leaves pricked from L. japonica plants, rinsed in autoclaved distilled water three times and dried with distilled filter paper. Then twelve healthy leave were inoculated with a mycelial plug (0.4 cm diameter) harvested from the periphery of two week-old colony. As negative control, leaves inoculated with PDA medium plugs. Inoculated leaves were covered with plastic bags to maintain high relative humidity and incubated at 25°C in growth chamber. After 7 days, the inoculated leaves showed symptoms identical to those observed in the field under natural conditions, whereas negative control remained symptom-free. Re-isolation of the fungus from lesions on inoculated leaves confirmed that the causal agent was C. cf. flagellaris. Pathogenicity tests were repeated three times by the same methods with the same results. To our knowledge, this is the first report of C. cf. flagellaris except Cercospora rhamni Fack., Alternaria alternata, Corynespora cassiicola or Phomopsis sp. causing leave spots on L. japonica in China.
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OBJECTIVE: To identify variables that may predict psychological distress in patients with an enterostomy. METHODS: Investigators recruited 77 patients with a stoma from a stoma clinic according to the inclusion criteria. Patients' psychological distress was assessed with the Distress Thermometer (DT) tool, and their personality type was determined by the Eysenck Personality Questionnaire. Researchers also collected demographic and disease-related data. Predictive values were estimated using multiple regression analyses. RESULTS: The mean DT score of all patients was 5.94 (SD, 1.81), and approximately 85.7% consistently suffered from psychological distress. Being unmarried and having peristomal complications were associated with higher psychological distress, whereas having a monthly income 5,000 ¥ or more was associated with lower levels of distress. Moreover, patients with a melancholic personality type tended to have higher DT scores, which could act as a strong independent predictor for psychological distress. CONCLUSIONS: The majority of patients with a stoma endured moderate to severe psychological distress during follow-up care. Exploring the related factors that predict the levels of psychological distress could enable clinicians to identify at-risk patients as early as possible and thus provide optimal care for improving patients' quality of life.
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Neoplasias Colorrectales , Enterostomía , Distrés Psicológico , Humanos , Estudios Transversales , Calidad de Vida/psicología , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/psicología , Estrés Psicológico/etiología , Estrés Psicológico/psicología , Encuestas y CuestionariosRESUMEN
Head rice yield (HRY) is an essential quality trait, and is sensitive to environmental stresses during the grain-filling, harvest, and postharvest stages. It is therefore important for rice production and global food security to select for superior HRY traits; however, the molecular basis of this trait remains unknown. Using diverse rice germplasm material, we performed a genome-wide association study of grain fissure resistance (GFR), the phenotype most associated with HRY, and found that the granule-bound starch synthase I gene Waxy is an important gene controlling GFR. Analysis of near-isogenic lines demonstrated that genetic variations in Waxy conferred different levels of tolerance to fissuring in grains. The null allele wx resulted in the highest GFR, while alleles that increased amylose synthesis reduced GFR. Increases in amylose content led to increases in the ratio of the widths of the amorphous layer to the semi-crystalline layer of the starch granules, and also to increased occurrence of chalkiness. The layer structure determined GFR by affecting the degree of swelling of granules in response to moisture, and chalkiness acted as an accelerator of moisture infiltration to rapidly increase the number of swelling granules. Our study reveals the molecular basis of GFR and HRY, thus opening the door for further understanding of the molecular networks of GFR and HRY.
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Oryza , Almidón Sintasa , Oryza/fisiología , Amilosa , Estudio de Asociación del Genoma Completo , Ceras , Almidón/química , Almidón Sintasa/genética , Grano Comestible/genéticaRESUMEN
Vegetation phenology has been viewed as the nature's calendar and an integrative indicator of plant-climate interactions. The correct representation of vegetation phenology is important for models to accurately simulate the exchange of carbon, water, and energy between the vegetated land surface and the atmosphere. Remote sensing has advanced the monitoring of vegetation phenology by providing spatially and temporally continuous data that together with conventional ground observations offers a unique contribution to our knowledge about the environmental impact on ecosystems as well as the ecological adaptations and feedback to global climate change. Land surface phenology (LSP) is defined as the use of satellites to monitor seasonal dynamics in vegetated land surfaces and to estimate phenological transition dates. LSP, as an interdisciplinary subject among remote sensing, ecology, and biometeorology, has undergone rapid development over the past few decades. Recent advances in sensor technologies, as well as data fusion techniques, have enabled novel phenology retrieval algorithms that refine phenology details at even higher spatiotemporal resolutions, providing new insights into ecosystem dynamics. As such, here we summarize the recent advances in LSP and the associated opportunities for science applications. We focus on the remaining challenges, promising techniques, and emerging topics that together we believe will truly form the very frontier of the global LSP research field.
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Cambio Climático , Ecosistema , Estaciones del Año , Carbono , AguaRESUMEN
Idiopathic pulmonary fibrosis (IPF) is a disease of progressive lung fibrosis with a high mortality rate. This study aimed to uncover the underlying molecular features for different types of IPF. IPF microarray datasets were retrieved from GEO databases. Weighted gene co-expression analysis (WGCNA) was used and identified subgroup-specific WGCNA modules. Infiltration-level immune cells in different subgroups of microenvironments were analyzed with CIBERSORT algorithms. The result is we classified 173 IPF cases into two subgroups based on gene expression profiles, which were retrieved from the GEO databases. The SGRQ score and age were significantly higher in C2 than in C1. Using WGCNA, five subgroup-specific modules were identified. M4 was mainly enriched by MAPK signaling, which was mainly expressed in C2; M1, M2, and M3 were mainly enriched by metabolic pathways and Chemokine signaling, and the pathway of M5 was phagosome inflammation; M1, M2, M3, and M5 were mainly expressed in C1. Utilizing the CIBERSORT, we showed that the number of M1 macrophage cells, CD8 T cells, regulatory T cells (Tregs), and Plasma cells was significantly different between C1 and C2. We found the molecular subgroups of IPF revealed that cases from different subgroups may have their unique patterns and provide novel information to understand the mechanisms of IPF itself.