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1.
J Cell Mol Med ; 28(8): e18335, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38652216

RESUMEN

Management of hepatocellular carcinoma (HCC) remains challenging due to population growth, frequent recurrence and drug resistance. Targeting of genes involved with the ferroptosis is a promising alternative treatment strategy for HCC. The present study aimed to investigate the effect of dihydroartemisinin (DHA) against HCC and explore the underlying mechanisms. The effects of DHA on induction of ferroptosis were investigated with the measurement of malondialdehyde concentrations, oxidised C11 BODIPY 581/591 staining, as well as subcutaneous xenograft experiments. Activated transcription factor 4 (ATF4) and solute carrier family 7 member 11 (SLC7A11 or xCT) were overexpressed with lentiviruses to verify the target of DHA. Here, we confirmed the anticancer effect of DHA in inducing ferroptosis is related to ATF4. High expression of ATF4 is related to worse clinicopathological prognosis of HCC. Mechanistically, DHA inhibited the expression of ATF4, thereby promoting lipid peroxidation and ferroptosis of HCC cells. Overexpression of ATF4 rescued DHA-induced ferroptosis. Moreover, ATF4 could directly bound to the SLC7A11 promoter and increase its transcription. In addition, DHA enhances the chemosensitivity of sorafenib on HCC in vivo and in vitro. These findings confirm that DHA induces ferroptosis of HCC via inhibiting ATF4-xCT pathway, thereby providing new drug options for the treatment of HCC.


Asunto(s)
Factor de Transcripción Activador 4 , Sistema de Transporte de Aminoácidos y+ , Artemisininas , Carcinoma Hepatocelular , Ferroptosis , Neoplasias Hepáticas , Ferroptosis/efectos de los fármacos , Artemisininas/farmacología , Artemisininas/uso terapéutico , Factor de Transcripción Activador 4/metabolismo , Factor de Transcripción Activador 4/genética , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Humanos , Animales , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Ratones , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Masculino , Ratones Desnudos , Sorafenib/farmacología , Sorafenib/uso terapéutico , Femenino , Ratones Endogámicos BALB C
2.
Anal Chem ; 96(6): 2658-2665, 2024 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-38311857

RESUMEN

Liquid biopsy is of great significance in tumor early diagnosis and treatment stratification. PD-L1-positive small extracellular vesicles (PD-L1+ sEVs) are closely related to tumor growth and immunotherapy response, which are considered valuable liquid biopsy biomarkers. In contrast to conventional in vitro detection, in vivo detection has the ability to improve the detection efficiency and enable continuous or real-time dynamic monitoring. However, in vivo detection of PD-L1+ sEVs has multiple difficulties, such as high cell background, complex blood environments, and lack of a specific and stable detection method. Herein, the in vivo detection of PD-L1+ sEVs method was constructed, which efficiently separated sEVs based on the microfluidic device and quantitatively analyzed PD-L1+ sEVs by aptamer recognition and hybridization chain reaction. The concentration of PD-L1+ sEVs was continuously monitored, and significant differences at different stages of tumor as well as a correlation with tumor volume were found. Diseased and healthy individuals could also be effectively distinguished based on the concentration of PD-L1+ sEVs. The method with good stability, biocompatibility, and detection performance provided a powerful means for in vivo detection of PD-L1+ sEVs, contributing to the clinical diagnosis and treatment of tumor.


Asunto(s)
Vesículas Extracelulares , Neoplasias , Humanos , Antígeno B7-H1 , Neoplasias/diagnóstico , Biopsia Líquida , Dispositivos Laboratorio en un Chip
3.
Metab Eng ; 84: 1-12, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38759777

RESUMEN

The development of synthetic microorganisms that could use one-carbon compounds, such as carbon dioxide, methanol, or formate, has received considerable interest. In this study, we engineered Pichia pastoris and Saccharomyces cerevisiae to both synthetic methylotrophy and formatotrophy, enabling them to co-utilize methanol or formate with CO2 fixation through a synthetic C1-compound assimilation pathway (MFORG pathway). This pathway consisted of a methanol-formate oxidation module and the reductive glycine pathway. We first assembled the MFORG pathway in P. pastoris using endogenous enzymes, followed by blocking the native methanol assimilation pathway, modularly engineering genes of MFORG pathway, and compartmentalizing the methanol oxidation module. These modifications successfully enabled the methylotrophic yeast P. pastoris to utilize both methanol and formate. We then introduced the MFORG pathway from P. pastoris into the model yeast S. cerevisiae, establishing the synthetic methylotrophy and formatotrophy in this organism. The resulting strain could also successfully utilize both methanol and formate with consumption rates of 20 mg/L/h and 36.5 mg/L/h, respectively. The ability of the engineered P. pastoris and S. cerevisiae to co-assimilate CO2 with methanol or formate through the MFORG pathway was also confirmed by 13C-tracer analysis. Finally, production of 5-aminolevulinic acid and lactic acid by co-assimilating methanol and CO2 was demonstrated in the engineered P. pastoris and S. cerevisiae. This work indicates the potential of the MFORG pathway in developing different hosts to use various one-carbon compounds for chemical production.


Asunto(s)
Dióxido de Carbono , Formiatos , Ingeniería Metabólica , Metanol , Saccharomyces cerevisiae , Formiatos/metabolismo , Metanol/metabolismo , Dióxido de Carbono/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismo , Saccharomycetales/genética
4.
Environ Sci Technol ; 58(12): 5383-5393, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38478982

RESUMEN

Cardiometabolic health is complex and characterized by an ensemble of correlated and/or co-occurring conditions including obesity, dyslipidemia, hypertension, and diabetes mellitus. It is affected by social, lifestyle, and environmental factors, which in-turn exhibit complex correlation patterns. To account for the complexity of (i) exposure profiles and (ii) health outcomes, we propose to use a multitrait Bayesian variable selection approach and identify a sparse set of exposures jointly explanatory of the complex cardiometabolic health status. Using data from a subset (N = 941 participants) of the nutrition, environment, and cardiovascular health (NESCAV) study, we evaluated the link between measurements of the cumulative exposure to (N = 33) pollutants derived from hair and cardiometabolic health as proxied by up to nine measured traits. Our multitrait analysis showed increased statistical power, compared to single-trait analyses, to detect subtle contributions of exposures to a set of clinical phenotypes, while providing parsimonious results with improved interpretability. We identified six exposures that were jointly explanatory of cardiometabolic health as modeled by six complementary traits, of which, we identified strong associations between hexachlorobenzene and trifluralin exposure and adverse cardiometabolic health, including traits of obesity, dyslipidemia, and hypertension. This supports the use of this type of approach for the joint modeling, in an exposome context, of correlated exposures in relation to complex and multifaceted outcomes.


Asunto(s)
Dislipidemias , Exposoma , Hipertensión , Humanos , Teorema de Bayes , Obesidad/epidemiología , Cabello , Exposición a Riesgos Ambientales
5.
J Biochem Mol Toxicol ; 38(9): e23794, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39163615

RESUMEN

Isoliensinine (ISO), a natural compound, is a bibenzyl isoquinoline alkaloid monomer in lotus seed, which has strong antioxidant and free radical scavenging activities. The oxidative toxicity caused by glutamic acid overdose is one of the important mechanisms of nerve cell injury, and the oxidative toxicity caused by glutamic acid is related to ferroptosis. This study aims to establish a glutamate-induced injury model of mouse hippocampal neurons HT-22 cells, and investigate the protective effect of ISO on the neurotoxicity of glutamate-induced HT-22 cells. The results showed that ISO inhibited glutamate-induced ferroptosis of neuronal cells through nuclear factor E2-related factor 2/glutathione peroxidase 4 (Nrf2/GPX4) signaling pathway. Pretreatment of HT-22 cells with ISO significantly reduced glutamate-induced cell death. Ferroptosis inhibitors have the same effect. ISO inhibited the decrease of mitochondrial membrane potential detection and the increase of iron content induced by glutamate, the increase of malondialdehyde and reactive oxygen species in cytoplasm and lipid, and protected the activities of GPx and superoxide dismutase enzymes. In addition, WB showed that glutamic acid could induce the upregulated expression of long-chain esteryl coA synthase 4 (ACSL4) protein and the downregulated expression of SLC7A11 and GPX4 protein in HT-22 cells, while ISO could prevent the abnormal expression of these proteins induced by glutamic acid. The nuclear translocation of Nrf2 in HT-22 cells was increased, and the expression of downstream heme oxygenase-1 protein was upregulated. In summary, ISO protects HT-22 cells from glutamate-induced ferroptosis through a novel mechanism of the Nrf2/GPX4 signaling pathway.


Asunto(s)
Ferroptosis , Ácido Glutámico , Factor 2 Relacionado con NF-E2 , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Transducción de Señal , Animales , Ferroptosis/efectos de los fármacos , Ratones , Ácido Glutámico/toxicidad , Ácido Glutámico/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Transducción de Señal/efectos de los fármacos , Línea Celular , Isoquinolinas/farmacología , Neuronas/efectos de los fármacos , Neuronas/metabolismo
6.
Biometals ; 37(4): 955-969, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38483766

RESUMEN

Iron is an essential element for the normal functioning of living organisms, but excessive iron deposition can lead to organ damage. This study aims to investigate the interaction between the endoplasmic reticulum stress signaling pathway and the PI3K/AKT/mTOR signaling pathway in liver injury induced by iron overload in chicks. Rspectively, 150 one-day-old broilers were divided into three groups and supplemented with 50 (C), 500 (E1), and 1000 (E2) mg ferrous sulfate monohydrate/kg in the basal diet. Samples were taken after continuous feeding for 14 days. The results showed that iron overload could upregulate the levels of ALT and AST. Histopathological examination revealed bleeding in the central vein of the liver accompanied by inflammatory cell infiltration. Hoechst staining showed that the iron overload group showed significant bright blue fluorescence, and ultrastructural observations showed chromatin condensation as well as mitochondrial swelling and cristae disorganization in the iron overload group. RT-qPCR and Western blot results showed that iron overload upregulated the expression of Bax, Caspase-3, Caspase-9, GRP78, GRP94, P-PERK, ATF4, eIF2α, IRE1, and ATF6, while downregulating the expression of Bcl-2 and the PI3K/AKT/mTOR pathway. XBP-1 splicing experiment showed significant splicing of XBP-1 gene after iron overload. PCA and correlation analysis suggested a potential association between endoplasmic reticulum stress, the PI3K/AKT/mTOR signaling pathway, and liver injury in chicks. In summary, iron overload can induce cell apoptosis and liver injury by affecting endoplasmic reticulum stress and the PI3K/AKT/mTOR signaling pathway.


Asunto(s)
Pollos , Estrés del Retículo Endoplásmico , Sobrecarga de Hierro , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Animales , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/patología , Hígado/metabolismo , Hígado/patología
7.
BMC Ophthalmol ; 24(1): 259, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38880899

RESUMEN

BACKGROUND: The anatomic structure of the anterior chamber (AC) helps to explain differences in refractive status in school-aged children and is closely associated with primary angle closure (PAC). The aim of this study was to quantify and analyze the anterior chamber and angle (ACA) characteristics in Chinese children with different refractive status by swept-source optical coherence tomography (SS-OCT). METHODS: In a cross-sectional observational study, 383 children from two primary schools in Shandong Province, China, underwent a complete ophthalmic examination. First, the anterior chamber depth (ACD), anterior chamber width (ACW), angle-opening distance (AOD), and trabecular-iris space area (TISA) were evaluated automatically using a CASIA2 imaging device. AOD and TISA were measured at 500, 750 µm nasal (N1 and N2, respectively), and temporal (T1 and T2, respectively) to the scleral spur (SS). Cycloplegic refraction and axial length (AL) were then measured. According to spherical equivalent refraction (SER), the children were assigned to hyperopic (SER > 0.50D), emmetropic (-0.50D < SER ≤ 0.50D), and myopic groups (SER ≤ -0.50D). RESULTS: Out of the 383 children, 349 healthy children (160 girls) with a mean age of 8.23 ± 1.06 years (range: 6-11 years) were included. The mean SER and AL were - 0.10 ± 1.57D and 23.44 ± 0.95 mm, respectively. The mean ACD and ACW were 3.17 ± 0.24 mm and 11.69 ± 0.43 mm. The mean AOD were 0.72 ± 0.25, 0.63 ± 0.22 mm at N1, T1, and 0.98 ± 0.30, 0.84 ± 0.27 mm at N2, T2. The mean TISA were 0.24 ± 0.09, 0.22 ± 0.09mm2 at N1, T1, and 0.46 ± 0.16, 0.40 ± 0.14mm2 at N2, T2. The myopic group had the deepest AC and the widest angle. Compared with boys, girls had shorter AL, shallower ACD, narrower ACW, and ACA (all p < 0.05). By Pearson's correlation analysis, SER was negatively associated with ACD, AOD, and TISA. AL was positively associated with ACD, ACW, AOD, and TISA. In the multiple regression analysis, AOD and TISA were associated with deeper ACD, narrower ACW, and longer AL. CONCLUSION: In primary school students, the myopic eyes have deeper AC and wider angle. ACD, ACW, AOD, and TISA all increase with axial elongation. ACA is highly correlated with deeper ACD.


Asunto(s)
Cámara Anterior , Refracción Ocular , Tomografía de Coherencia Óptica , Humanos , Tomografía de Coherencia Óptica/métodos , Estudios Transversales , Niño , Femenino , Masculino , Cámara Anterior/diagnóstico por imagen , Cámara Anterior/patología , China/epidemiología , Refracción Ocular/fisiología , Glaucoma de Ángulo Cerrado/fisiopatología , Glaucoma de Ángulo Cerrado/diagnóstico , Glaucoma de Ángulo Cerrado/etnología , Errores de Refracción/fisiopatología , Pueblos del Este de Asia
8.
Molecules ; 29(7)2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38611742

RESUMEN

Tumor vaccines have been considered a promising therapeutic approach for treating cancer in recent years. With the development of sequencing technologies, tumor vaccines based on neoantigens or genomes specifically expressed in tumor cells, mainly in the form of peptides, nucleic acids, and dendritic cells, are beginning to receive widespread attention. Therefore, in this review, we have introduced different forms of neoantigen vaccines and discussed the development of these vaccines in treating cancer. Furthermore, neoantigen vaccines are influenced by factors such as antigen stability, weak immunogenicity, and biosafety in addition to sequencing technology. Hence, the biological nanomaterials, polymeric nanomaterials, inorganic nanomaterials, etc., used as vaccine carriers are principally summarized here, which may contribute to the design of neoantigen vaccines for improved stability and better efficacy.


Asunto(s)
Vacunas contra el Cáncer , Nanoestructuras , Neoplasias , Ácidos Nucleicos , Humanos , Vacunas contra el Cáncer/uso terapéutico , Medicina de Precisión , Nanoestructuras/uso terapéutico , Neoplasias/terapia
9.
Int Nurs Rev ; 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39434679

RESUMEN

AIMS: To investigate the effect of ward operational efficiency on nursing workload and identify the factors that influence nursing workload. BACKGROUND: It remains unclear how and to what extent ward operational efficiency can influence nursing workload. METHODS: A prospective observational study was conducted from July 1, 2022 to June 30, 2023, in one tertiary general hospital in China. Purposive and convenience sampling was used, and 266 470 patients from 66 wards and 52 nurses from 13 wards were recruited. The relationships between operational efficiency and nursing workload and the predictors of nursing workload were analyzed. The STROBE guidelines were followed. RESULTS: The operational characteristics vary by the type of wards. Nursing workloads were positively correlated with case mix index (CMI), rate of level 4 surgery, the number of patients transferred in and out, the number of deaths, total bed days, and the number of emergency admissions and critical illnesses (γs: 0.35-0.56, p < 0.05). And the CMI, rate of level 4 surgery, average bed occupancy rate, number of critically ill patients, and total bed days were the predictors of nursing workload (R2 = 57.3%, p < 0.05). DISCUSSION: This study is the first to discuss the relationship between operational efficiency and nursing workload on the ward level and offers valuable insights into the nursing workload. CONCLUSION: The operational efficiency of wards affects the nursing workload and needs to be considered both in the measurement of nursing activities and in the sizing of the nursing staff. IMPLICATIONS FOR NURSING AND NURSING POLICY: The study findings provide a full understanding of the relationship between ward operation and nurse staffing, which is helpful for nursing managers to formulate scientific nurse staffing policies.

10.
Angew Chem Int Ed Engl ; 63(45): e202412681, 2024 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-39115363

RESUMEN

Doping of polycyclic conjugated hydrocarbons (PCHs) with sulfur atoms is becoming more and more important as a means of creating unique functional materials. Recently, thiophene-containing multiple helicenes have garnered enormous attention due to their intriguing electronic and (chir)optical properties compared with carbohelicenes. However, the efficient synthesis of thiopyran-containing multiple helicenes and the underlying sulfur doping mechanisms are rather unexplored. Herein, the synthesis and structural analysis of a thiopyran-containing double [7]helicene 3 are reported. X-ray crystallographic analysis reveals 3 and its dication with C2-symmetric propeller-shape structures and compact interactions in the solid state. 3 exhibits deep-red to near-infrared (NIR) fluorescence emission. Tunable aromaticity of the central benzene ring and thiopyran rings is found by chemical oxidation, which is further confirmed by nucleus-independent chemical shift (NICS), anisotropy of the induced current density (ACID) and harmonic oscillator model of aromaticity (HOMA) analysis. Furthermore, the chiral and photosensitizing characters of 3 are investigated. The excellent deep-red to NIR fluorescence, circularly polarized luminescence (CPL) and photosensitizing activities suggest that 3 can be used as an outstanding photosensitizer in photodynamic therapy (PDT) and bioimaging, especially paving the way for future CPL-PDT and CPL-bio-probe applications.

11.
Anal Chem ; 95(19): 7753-7760, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37130010

RESUMEN

Extracellular vesicles (EVs), acting as important mediators of intercellular communication, play an essential role in physiological processes, which have unique potential in the medical field. However, the heterogeneity of EVs limits their development for disease diagnosis and therapy, making the EV subpopulation analysis extremely valuable. In this article, a simple microfluidic approach was presented for the on-chip specific isolation and detection of two phenotypes of EVs (Annexin V+ EGFR+ EVs and Annexin V- EGFR+ EVs) based on different biomolecule-modified magnetic nanospheres and a fluorescence labeling technique. Combined with the control of the magnetic field in the microzone and fluid flow, it was easy to form two separate functional regions in the chip to capture different EV subpopulations. This method was successfully applied to the tests of clinical saliva samples in 75 oral squamous cell carcinoma (OSCC) patients and 10 healthy people. The results showed that the total level of EGFR+ EVs was much higher in OSCC patients that in healthy people. Meantime, the ratio of Annexin V+ EGFR+ EVs to Annexin V- EGFR+ EVs was found to be negatively correlated with tumor T stage of OSCC patients with a statistical difference, which suggested the ratio as a clinical index for monitoring the progression of OSCC in real time based on a noninvasive method. The approach provided a novel idea for evaluating the tumor T stage of OSCC and a powerful tool for clinical application.


Asunto(s)
Carcinoma de Células Escamosas , Vesículas Extracelulares , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patología , Neoplasias de la Boca/diagnóstico , Neoplasias de la Boca/patología , Carcinoma de Células Escamosas de Cabeza y Cuello , Saliva/metabolismo , Anexina A5 , Vesículas Extracelulares/metabolismo , Neoplasias de Cabeza y Cuello/patología , Receptores ErbB/metabolismo
12.
Anal Chem ; 95(22): 8735-8743, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-37218037

RESUMEN

Liquid biopsy technology involves taking samples from body fluids in a minimally invasive way and analyzing tumor markers to achieve early diagnosis and efficacy evaluation of tumors. The development of real-time cancer diagnosis and treatment strategies based on liquid biopsy technology is of great significance to cancer management. This paper described an extracorporeal circulation based on a three-dimensional (3D) magnetic chip (3DMC-system) for in vivo detection and real-time monitoring of circulating tumor cells (CTCs). Utilizing biofunctionalized magnetic nanospheres (MNs) with CTC recognition function, this 3DMC-system could effectively achieve the real-time monitoring of CTCs in vivo with good stability and strong anti-interference. Compared with in vitro CTC detection, in vivo detection could not only detect more CTCs but also detect the presence of CTCs in the blood at an early stage of the tumor, when tumor metastasis is not observed in imaging. In addition, due to the flexibility of the chip design, the system can easily add a treatment module to integrate cancer diagnosis and treatment together. With good biocompatibility and high stability, this 3DMC-system is expected to provide a new personalized medical program for cancer patients.


Asunto(s)
Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patología , Fenómenos Magnéticos , Circulación Extracorporea , Biomarcadores de Tumor
13.
Glob Chang Biol ; 29(15): 4430-4439, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37194010

RESUMEN

Microbial residues contribute to the long-term stabilization of carbon in the entire soil profile, helping to regulate the climate of the planet; however, how sensitive these residues are to climatic seasonality remains virtually unknown, especially for deep soils across environmental gradients. Here, we investigated the changes of microbial residues along soil profiles (0-100 cm) from 44 typical ecosystems with a wide range of climates (~3100 km transects across China). Our results showed that microbial residues account for a larger portion of soil carbon in deeper (60-100 cm) vs. shallower (0-30 and 30-60 cm) soils. Moreover, we find that climate especially challenges the accumulation of microbial residues in deep soils, while soil properties and climate share their roles in controlling the residue accumulation in surface soils. Climatic seasonality, including positive correlations with summer precipitation and maximum monthly precipitation, as well as negative correlations with temperature annual range, are important factors explaining microbial residue accumulation in deep soils across China. In particular, summer precipitation is the key regulator of microbial-driven carbon stability in deep soils, which has 37.2% of relative independent effects on deep-soil microbial residue accumulation. Our work provides novel insights into the importance of climatic seasonality in driving the stabilization of microbial residues in deep soils, challenging the idea that deep soils as long-term carbon reservoirs can buffer climate change.


Asunto(s)
Carbono , Microbiología del Suelo , Suelo , Carbono/análisis , China , Cambio Climático , Ecosistema , Suelo/química
14.
Glob Chang Biol ; 29(15): 4412-4429, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37277945

RESUMEN

Microbial communities in soils are generally considered to be limited by carbon (C), which could be a crucial control for basic soil functions and responses of microbial heterotrophic metabolism to climate change. However, global soil microbial C limitation (MCL) has rarely been estimated and is poorly understood. Here, we predicted MCL, defined as limited availability of substrate C relative to nitrogen and/or phosphorus to meet microbial metabolic requirements, based on the thresholds of extracellular enzyme activity across 847 sites (2476 observations) representing global natural ecosystems. Results showed that only about 22% of global sites in terrestrial surface soils show relative C limitation in microbial community. This finding challenges the conventional hypothesis of ubiquitous C limitation for soil microbial metabolism. The limited geographic extent of C limitation in our study was mainly attributed to plant litter, rather than soil organic matter that has been processed by microbes, serving as the dominant C source for microbial acquisition. We also identified a significant latitudinal pattern of predicted MCL with larger C limitation at mid- to high latitudes, whereas this limitation was generally absent in the tropics. Moreover, MCL significantly constrained the rates of soil heterotrophic respiration, suggesting a potentially larger relative increase in respiration at mid- to high latitudes than low latitudes, if climate change increases primary productivity that alleviates MCL at higher latitudes. Our study provides the first global estimates of MCL, advancing our understanding of terrestrial C cycling and microbial metabolic feedback under global climate change.


Asunto(s)
Ecosistema , Microbiota , Carbono/metabolismo , Suelo , Microbiología del Suelo , Cambio Climático , Nitrógeno/análisis
15.
J Org Chem ; 88(9): 5291-5299, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37079904

RESUMEN

Fusion selenophene endows the chromophore with more intrinsic and special functions. Herein, nonsymmetric selenophene-fused BODIPYs were designed and synthesized starting from the selenophene unit. The fused ring of selenophene not only maintains the rigid structure of BODIPY but also further modulates its spectral properties. The newly prepared dyes possessed many promising properties including large molar extinction coefficients, low fluorescence quantum yields, and moderate singlet oxygen generation. Quantum calculations affirmed that the smaller singlet-triplet energy gap and larger spin-orbit coupling cause efficient intersystem crossing, thus enhancing the singlet oxygen generation yield. Furthermore, selenophene-fused BODIPY exhibited significant phototoxicity with negligible dark cytotoxicity, based on the fluorescence imaging of the reactive oxygen species detection experiment.

16.
Environ Sci Technol ; 57(48): 19383-19394, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37934613

RESUMEN

Organic pollutant exposure may alter sex steroid hormone levels in both animals and humans, but studies on mixture effects have been lacking and mainly limited to persistent organic pollutants, with few hormones being investigated. Moreover, measurements from a single blood or urine sample may not be able to reflect long-term status. Using hair analysis, here, we evaluated the relationship between multiclass organic pollutants and sex steroid hormones in 196 healthy Chinese women aged 25-45 years. Associations with nine sex steroid hormones, including progesterone, androstenedione (AD), testosterone (T), estrone (E1), and 17ß-estradiol (E2), and eight related hormone ratios were explored on 54 pollutants from polychlorinated biphenyl (PCB), pesticide, and bisphenol families using stability-based Lasso regression analysis. Our results showed that each hormone was associated with a mixture of at least 10 examined pollutants. In particular, hair E2 concentration was associated with 19 pollutants, including γ-hexachlorocyclohexane, propoxur, permethrin, fipronil, mecoprop, prochloraz, and carbendazim. There were also associations between pollutants and hormone ratios, with pentachlorophenol, dimethylthiophosphate, 3-phenoxybenzoic acid, and flusilazole being related to both E1/AD and E2/T ratios. Our results suggest that exposure to background levels of pesticides PCB180 and bisphenol S may affect sex steroid hormone homeostasis among women of reproductive age.


Asunto(s)
Contaminantes Ambientales , Plaguicidas , Bifenilos Policlorados , Animales , Humanos , Femenino , Contaminantes Ambientales/análisis , Exposición a Riesgos Ambientales/análisis , Hormonas Esteroides Gonadales , Bifenilos Policlorados/análisis , Testosterona/análisis , Plaguicidas/análisis
17.
Macromol Rapid Commun ; 44(21): e2300358, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37572054

RESUMEN

Flame retardant treatment of epoxy resins (EP) to reduce their flammability for extending their range of applications attracts considerable attention. However, the synthesis process of conventional flame retardants is complicated and involves organic hazardous solvents. Meanwhile, how to ensure both the flame-retardant and mechanical properties is a long-standing and actual difficult problem. In this work, a supramolecular flame retardant (named ATPFR) is facilely created by one-pot reaction, using cheap and accessible raw materials in an ecologically benign aqueous solvent. ATPFR is applied to improve the fire safety of EP. With only 5 wt% ATPFR addition, EP can reach the limiting oxygen index of 28.5% and the UL-94 V-0 rating with a significant "blow-out effect." The cone calorimetry test reveals that the EP thermoset with 5 wt% ATPFR has a 75.8% reduction in the peak heat release rate (p-HRR) and a 67.3% reduction in the peak smoke production rate (p-SPR), respectively, compared with the pure EP. Additionally, EP composites with the small amount of ATPFR exhibit a slight decrease and maintain good mechanical properties. Therefore, the facile synthesis and application of this supramolecular flame retardant provide a reliable way for the construction of polymer materials with environment-friendly and effective flame-retardant system.


Asunto(s)
Resinas Epoxi , Retardadores de Llama , Calorimetría , Calor , Oxígeno , Solventes
18.
Eur J Clin Pharmacol ; 79(5): 663-670, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36976322

RESUMEN

OBJECTIVE: Sacubitril/valsartan is a commonly used medicine for treating heart failure (HF) patients, but the treatment effects significantly vary. Neprilysin (NEP) and carboxylesterase 1 (CES1) play an important role in the efficacy of sacubitril/valsartan. The purpose of this study was to explore the relationship between NEP and CES1 gene polymorphisms and the efficacy and safety of sacubitril/valsartan treatment in HF patients. METHODS: Genotyping of 10 single nucleotide polymorphisms (SNPs) of the NEP and CES1 genes in 116 HF patients was performed by the Sequenom MassARRAY method, and logistic regression and haplotype analysis were used to evaluate the associations between SNPs and the clinical efficacy and safety of sacubitril/valsartan in HF patients. RESULTS: A total of 116 Chinese patients with HF completed the whole trial, and T variations in rs701109 in NEP gene were an independent risk factor (P = 0.013, OR = 3.292, 95% CI:1.287-8.422) for the clinical efficacy of sacubitril/valsartan. Furthermore, haplotype analysis of 6 NEP SNPs (including rs701109) was performed and showed that the CGTACC and TGTACC haplotypes were significantly associated with clinical efficacy (OR = 0.095, 95%CI: 0.012-0.723, P = 0.003; OR = 5.586, 95% CI: 1.621-19.248, P = 0.005). Moreover, no association was found between SNPs of other selected genes in terms of efficacy in HF patients, and no association was observed between SNPs and symptomatic hypotension. CONCLUSION: Our results suggest an association between rs701109 and sacubitril/valsartan response in HF patients. Symptomatic hypotension is not associated with the presence of NEP polymorphisms.


Asunto(s)
Insuficiencia Cardíaca , Hipotensión , Neprilisina , Humanos , Aminobutiratos/uso terapéutico , Antagonistas de Receptores de Angiotensina/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Combinación de Medicamentos , Pueblos del Este de Asia , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/genética , Hipotensión/inducido químicamente , Hipotensión/genética , Neprilisina/genética , Polimorfismo Genético , Volumen Sistólico , Tetrazoles/uso terapéutico , Resultado del Tratamiento , Valsartán/uso terapéutico
19.
Bioorg Chem ; 137: 106617, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37267793

RESUMEN

Artemyrianolide H (AH) is a germacrene-type sesquiterpenolid isolated from Artemisia myriantha, and showed potent cytotoxicity against three human hepatocellular carcinoma cell lines HepG2, Huh7, and SK-Hep-1 with IC50 values of 10.9, 7.2, and 11.9 µM, respectively. To reveal structure-activity relationship, 51 artemyrianolide H derivatives including 19 dimeric analogs were designed, synthesized, and assayed for their cytotoxicity against three human hepatoma cell lines. Among them, 34 compounds were more active than artemyrianolide H and sorafenib on the three cell lines. Especially, compound 25 exhibited the most promising activity with IC50 values of 0.7 (HepG2), 0.6 (Huh7), and 1.3 µM (SK-Hep-1), which were 15.5, 12.0, and 9.2-fold higher than that of AH and 16.4, 16.3 and 17.5-fold higher than that of sorafenib. Cytotoxicity evaluation on normal human liver cell lines (THLE-2) demonstrated good safety profile of compound 25 with SI of 1.9 (HepG2), 2.2 (Huh 7) and 1.0 (SK-Hep1). Further studies revealed that compound 25 dose-dependently arrested cells at G2/M phase which was correlated with the up-regulation of both cyclin B1 and p-CDK1, and induced apoptosis through the activation of mitochondrial pathways in HepG2 cells. In addition, the migratory and invasive abilities in HepG2 cells after treatment with 1.5 µM of compound 25 were decreased by 89% and 86% with the increase of E-cadherin expression accompanied by the decrease of N-cadherin, vimentin expression. Bioinformatics analysis based on machine learning predicted that PDGFRA and MAP2K2 might be acting targets of compound 25, and SPR assays demonstrated compound 25 were bound with PDGFRA and MAP2K2 with KD value of 0.168 nM, and 8.49 µM, respectively. This investigation proposed that compound 25 might be considered as a promising lead compound for the development of antihepatoma candidate.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Sorafenib/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/patología , Relación Estructura-Actividad , Células Hep G2 , Proliferación Celular , Apoptosis , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular Tumoral
20.
Int J Clin Pharmacol Ther ; 61(3): 129-138, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36458443

RESUMEN

OBJECTIVE: To evaluate the pharmacokinetics (PK), safety, and bioequivalence of two formulations of apixaban in healthy Chinese subjects under fasting and fed conditions. MATERIALS AND METHODS: A single-center, randomized, open, single-dose, two-period crossover PK study was carried out under fasting and fed conditions in 64 healthy subjects enrolled in either the fasting (36 subjects) or the fed (28 subjects) arms of the study. Subjects received a single oral dose of 2.5 mg apixaban tablets as test (T) or reference (R) formulation. The primary PK parameters determined were the area under the plasma concentration-time curve from zero to t and ∞ (AUC0-t and AUC0-∞) and the maximal plasma concentration (Cmax). Safety was assessed mainly from the occurrence of adverse events (AEs). RESULTS: A single drop-out in the fed arm of the trial was excluded from the statistical evaluation. The 90% confidence intervals (CIs) for the geometric mean ratio (GMR) for T/R using AUC0-t were 95.4 - 100.9% and 97.8 - 103.8%, and for AUC0-∞ were 95.3 - 100.6% and 98.3 - 104.3% under fasting (36 subjects) and fed (27 subjects) conditions, respectively. Similarly, the 90% CIs for Cmax were 94.6 - 103.1% and 88.8 - 102.0% under fasting (36 subjects) and the fed (27 subjects) conditions, respectively. Therefore, the 90% CIs for the T/R AUC and Cmax ratios were within the standard range for bioequivalence (80.0 - 125.0%). There were no serious adverse events (SAEs). CONCLUSION: The test and reference 2.5 mg apixaban tablets were bioequivalent and both showed good tolerability and safety.


Asunto(s)
Pueblos del Este de Asia , Pirazoles , Piridonas , Equivalencia Terapéutica , Humanos , Área Bajo la Curva , Estudios Cruzados , Ayuno , Voluntarios Sanos , Comprimidos , Pirazoles/farmacocinética , Piridonas/farmacocinética
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