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Unlike many studies that regulate transport and separation behaviour of photogenerated charge carriers through controlling the chemical composite, our work demonstrates this goal can be achieved through simply tuning the molecular π-π packing from short-range to long-range within hydrogen-bonded organic frameworks (HOFs) without altering the building blocks or network topology. Further investigations reveal that the long-range π-π stacking significantly promotes electron delocalization and enhances electron density, thereby effectively suppressing electron-hole recombination and augmenting the charge transfer rate. Simultaneously, acting as a porous substrate, it boosts electron density of Pd nanoparticle loaded on its surfaces, resulting in remarkable CO2 photoreduction catalytic activity (CO generation rate: 48.1 µmol/g/h) without the need for hole scavengers. Our study provide insight into regulating the charge carrier behaviours in molecular assemblies based on hydrogen bonds, offering a new clue for efficient photocatalyst design.
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BACKGROUND: Hepatocellular carcinoma (HCC) has a high incidence and mortality worldwide, which seriously threatens people's physical and mental health. Coagulation is closely related to the occurrence and development of HCC. Whether coagulation-related genes (CRGs) can be used as prognostic markers for HCC remains to be investigated. METHODS: Firstly, we identified differentially expressed coagulation-related genes of HCC and control samples in the datasets GSE54236, GSE102079, TCGA-LIHC, and Genecards database. Then, univariate Cox regression analysis, LASSO regression analysis, and multivariate Cox regression analysis were used to determine the key CRGs and establish the coagulation-related risk score (CRRS) prognostic model in the TCGA-LIHC dataset. The predictive capability of the CRRS model was evaluated by Kaplan-Meier survival analysis and ROC analysis. External validation was performed in the ICGC-LIRI-JP dataset. Besides, combining risk score and age, gender, grade, and stage, a nomogram was constructed to quantify the survival probability. We further analyzed the correlation between risk score and functional enrichment, pathway, and tumor immune microenvironment. RESULTS: We identified 5 key CRGs (FLVCR1, CENPE, LCAT, CYP2C9, and NQO1) and constructed the CRRS prognostic model. The overall survival (OS) of the high-risk group was shorter than that of the low-risk group. The AUC values for 1 -, 3 -, and 5-year OS in the TCGA dataset were 0.769, 0.691, and 0.674, respectively. The Cox analysis showed that CRRS was an independent prognostic factor for HCC. A nomogram established with risk score, age, gender, grade, and stage, has a better prognostic value for HCC patients. In the high-risk group, CD4+T cells memory resting, NK cells activated, and B cells naive were significantly lower. The expression levels of immune checkpoint genes in the high-risk group were generally higher than that in the low-risk group. CONCLUSIONS: The CRRS model has reliable predictive value for the prognosis of HCC patients.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Pronóstico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Nomogramas , Factores de Riesgo , Microambiente TumoralRESUMEN
Strong, psychedelic indolethylamines (IAAs) are typically present in trace amounts in the majority of species, but they build up significantly in the skin of amphibian toads, especially N-methylated 5-hydroxytryptamine (5-HT) analogues. However, there is no pertinent research on the investigation of indoleamine N-methyltransferase (INMT) in amphibians, nor is there any adequate information on the key amino acids that influence the activity of known INMTs from other species. Herein, we focused on Bufo toad INMT (BINMT) for the first time and preliminarily identified BINMT 1 from the transcriptomes of Bufo gargarizans active on tryptamine, 5-HT, and N-methyl-5-HT. We established the enzyme kinetic characteristics of BINMT 1 and identified the essential amino acids influencing its activity via molecular docking and site-directed mutagenesis. Subsequently, we carried out sequence alignment and phylogenetic tree analysis on 43 homologous proteins found in the genome of B. gargarizans with BINMT 1 as the probe and selected seven of them for protein expression and activity assays. It was found that only three proteins possessing the highest similarity to BINMT 1 had INMT activity. Our research unveils the binding residues of BINMT for 5-HT analogues for the first time and initiates the study of INMTs in amphibian toads, serving as a tentative reference for further study of BINMT and providing insight into the comprehension of BINMT's catalytic mechanism and its role in the biosynthesis of 5-HT analogues in Bufo toads. It also contributes to the expansion of the INMT library to help explore and explain interspecies evolution in the future.
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Bufonidae , Serotonina , Animales , Serotonina/metabolismo , Simulación del Acoplamiento Molecular , Filogenia , Bufonidae/genética , Bufonidae/metabolismo , Metiltransferasas/metabolismoRESUMEN
Rational design and regulation of atomically precise photocatalysts are essential for constructing efficient photocatalytic systems tunable at both the atomic and molecular levels. Herein, we propose a platform-based strategy capable of integrating both pore space partition (PSP) and open-metal sites (OMSs) as foundational features for constructing high-performance photocatalysts. We demonstrate the first structural prototype obtained from this strategy: pore-partitioned NiTCPE-pstp (TCPE = 1,1,2,2-tetra(4-carboxylphenyl)ethylene, pstp = partitioned stp topology). Nonpartitioned NiTCPE-stp is constructed from six-connected [Ni3(µ3-OH)(COO)6] trimer and TCPE linker to form 1D hexagonal channels with six coplanar OMSs directed at channel centers. After introducing triangular pore-partitioning ligands, half of the OMSs were retained, while the other half were used for PSP, leading to unprecedented microenvironment regulation of the pore structure. The resulting material integrates multiple advanced properties, including robustness, wider absorption range, enhanced electronic conductivity, and high CO2 adsorption, all of which are highly desirable for photocatalytic applications. Remarkably, NiTCPE-pstp exhibits excellent CO2 photoreduction activity with a high CO generation rate of 3353.6 µmol g-1 h-1 and nearly 100% selectivity. Theoretical and experimental studies show that the introduction of partitioning ligands not only optimizes the electronic structure to promote the separation and transfer of photogenerated carriers but also reduces the energy barrier for the formation of *COOH intermediates while promoting CO2 activation and CO desorption. This work is believed to be the first example to integrate PSP strategies and OMSs within metal-organic framework (MOF) photocatalysts, which provides new insight as well as new structural prototype for the design and performance optimization of MOF-based photocatalysts.
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BACKGROUND: Dinutuximab ß can be used to treat children with high-risk neuroblastoma (NB). Due to its high price, whether dinutuximab ß is cost-effective for the treatment of high-risk NB remains uncertain. Therefore, assessing the cost-effectiveness of dinutuximab ß in children with high-risk NB is of high importance. METHODS: The health utilities and economic outcomes in children with high-risk NB were projected using a partitioned survival model. The individual patient data (IPD) of add-on treatment with dinutuximab ß (GD2 group) were derived from the literature, while the IPD of traditional therapy (TT group) were obtained from retrospective data of Shanghai Children's Medical Center. Treatment costs included drugs, adverse event-related expenses, and medical resource use. Utility values were obtained from the literature. Costs and quality-adjusted life-years (QALYs) were measured over a 10-year time horizon. Deterministic sensitivity analyses (DSA) and probabilistic sensitivity analyses (PSA) were also conducted. RESULTS: Compared with the TT group, QALY increased in the GD2 group by 0.72 with an increased cost of $171,269.70, leading to an incremental cost-effectiveness ratio of 236,462.75$/QALY. DSA showed that the price of dinutuximab ß was the main factor on the results than other parameters. Compared with the TT group, the GD2 group could not be cost-effective in the PSA at the $37,920/QALY threshold. CONCLUSION: Results found that dinutuximab ß is not a cost-effective treatment option for children with high-risk NB unless its price is significantly reduced.
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A two-dimensional metal-organic framework, FICN-12, was constructed from tris[4-(1H-pyrazole-4-yl)phenyl]amine (H3TPPA) ligands and Ni2 secondary building units. The triphenylamine moiety in the H3TPPA ligand readily absorbs UV-visible photons and sensitizes the Ni center to drive photocatalytic CO2 reduction. FICN-12 can be exfoliated into monolayer and few-layer nanosheets with a "top-down" approach, which exposes more catalytic sites and increases its catalytic activity. As a result, the nanosheets (FICN-12-MONs) showed photocatalytic CO and CH4 production rates of 121.15 and 12.17 µmol/g/h, respectively, nearly 1.4 times higher than those of bulk FICN-12.
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In natural photosynthesis, the architecture of multiproteins integrates more chromophores than redox centers and simultaneously creates a well-controlled environment around the active site. Herein, we demonstrate that these features can be emulated in a prototype hydrogen-bonded organic framework (HOF) through simply varying the proportion of metalated porphyrin in the structure. Further studies demonstrate that changing the metalloporphyrin content not only realizes a fine tuning of the photosensitizer/catalyst ratio, but also alters the microenvironment surrounding the active site and the charge separation efficiency. As a result, the obtained material achieves the challenging overall CO2 reduction with a high HCOOH production rate (29.8â µmol g-1 h-1 , scavenger free), standing out from existing competitors. This work unveils that the degree of metalation is vital to the catalytic activity of the porphryinic framework, presenting as a new strategy to optimize the performance of heterogeneous catalysts.
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Under topological guidance, the self-assembly process based on a tetratopic porphyrin synthon results in a hydrogen-bonded organic framework (HOF) with the predicted square layers topology (sql) but unsatisfied stability. Strikingly, simply introducing a transition metal in the porphyrin center does not change the network topology but drastically causes noticeable change on noncovalent interaction, orbital overlap, and molecular geometry, therefore ultimately giving rise to a series of metalloporphyrinic HOFs with high surface area, and excellent stability (intact after being soaked in boiling water, concentrated HCl, and heated to 270 °C). On integrating both photosensitizers and catalytic sites into robust backbones, this series of HOFs can effectively catalyze the photoreduction of CO2 to CO, and their catalytic performances greatly depend on the chelated metal species in the porphyrin centers. This work enriches the library of stable functional HOFs and expands their applications in photocatalytic CO2 reduction.
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Porous materials have been investigated as efficient photochromic platforms for detecting hazardous radiation, while the utilization of hydrogen bonded organic frameworks (HOFs) in this field has remained intact. Herein, two HOFs were synthesized through self-assembly of tetratopic viologen ligand and formic acid (PFC-25, PFC-26), as a new class of "all-organic" radiochromic smart material, opening a gate for HOFs in this field. PFC-26 is active upon both X-ray and UV irradiation, while PFC-25 is only active upon X-ray irradiation. The same building block yet different radiochromic behaviors of PFC-25 and PFC-26 allow us to gain a deep mechanistic understanding of the factors that control the detection specificity. Theoretical and experimental studies reveal that the degree of π-conjugation of viologen ligand is highly related to the threshold energy of triggering a charge transfer, therefore being a vital factor for the particularity of radiochromic materials. Thanks to its convenient processibility, nanoparticle size, and UV silence, PFC-25 can be further fabricated into a portable naked-eye sensor for X-ray detection, which shows obvious color change with the merits of high transmittance contrast, good sensitivity (reproducible dose threshold of 3.5â Gy), and excellent stability. The work exhibits the promising practical potentials of HOF materials in photochromic technology.
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Hidrógeno , Viológenos , Enlace de Hidrógeno , Rayos XRESUMEN
Although many ionic metal-organic frameworks (MOFs) have been reported, little is known about how the charge of the skeleton affects the properties of the MOF materials. Herein we report how the chemical stability of MOFs can be substantially improved through embedding electrostatic interactions in structure. A MOF with a cationic skeleton is impervious to extremely acidic, oxidative, reductive, and high ionic strength conditions, such as 12 m HCl (301â days), aqua regia (86â days), H2 O2 (30â days), and seawater (30â days), which is unprecedented for MOFs. DFT calculations suggested that steric hinderance and the repulsive interaction of the cationic framework toward positively charged species in microenvironments protects the vulnerable bonds in the structure. Diverse functionalities can be bestowed by substituting the counterions of the charged framework with identically charged functional species, which broadens the horizon in the design of MOFs adaptable to a demanding environment with specific functionalities.
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A novel tetrabutylammonium iodide (TBAI)-promoted three-component reaction of carboxylic acid with alkene and alcohol has been developed, which represents facile and straightforward access to polysubstituted γ-lactone skeletons in moderate-to-good yields. This methodology is distinguished by the use of a commercial catalyst and readily available starting materials, wide substrate scope, and operational simplicity. Mechanistic studies suggested that this transformation went through a radical process.
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Elevated homocysteine levels are known to be a risk factor for congenital cardiac septal defects (CCSDs), but the mechanism underlying this effect is unknown. The genetic variants that were significantly associated with circulating homocysteine concentrations have been systematically identified through the genome-wide association studies of one-carbon core metabolites. To examine the role of the genome-wide significant homocysteine related variants in the occurrence of CCSDs, we investigated the association between these variants and CCSDs in Han Chinese populations. Five variants of the genome-wide significant homocysteine-related genes were selected for analysis in two stages of case-controlled studies with a total of 904 CCSD patients and 997 controls. SYT9 expression was detected in human cardiovascular tissue using qRT-PCR. The intronic variant rs11041321 of the SYT9 gene was associated with an increased risk of developing CCSDs in both the separate and combined case-controlled studies. Combined samples from the two stage cohorts had a significant elevation in CCSD risk for the T allele (OR = 1.43, P = 2.6 × 10-6 ), CT genotype and TT genotype (CT: OR = 1.30, TT: OR = 2.21; P = 1 × 10-4 ) compared with the wild-type C allele and CC genotype, respectively. The risky T allele carriers exhibited decreased SYT9 mRNA expression, compared with wild-type C allele carriers. The intronic SYT9 variant rs11041321, which exhibits a significant genome-wide association with circulating homocysteine, was associated with the occurrence of CCSDs. This finding helps to characterize the unexpected role of SYT9 in homocysteine metabolism and the development of CCSDs, which further highlighted the interplay of diet, genetics, and human birth defects. © 2017 IUBMB Life, 69(9):700-705, 2017.
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Predisposición Genética a la Enfermedad , Defectos de los Tabiques Cardíacos/genética , Homocisteína/genética , Sinaptotagminas/genética , Alelos , Femenino , Expresión Génica/genética , Estudios de Asociación Genética , Genotipo , Defectos de los Tabiques Cardíacos/patología , Homocisteína/metabolismo , Humanos , Masculino , Polimorfismo de Nucleótido Simple/genética , Factores de RiesgoRESUMEN
In current work, the effect of ripening stages (I, II, and III) on pulsed vacuum drying (PVD) behavior of goji berry was explored. The shortest drying time of goji berry was observed at stage I (6.99 h) which was 13.95 %, and 28.85 % shorter than those at stages II, and III, respectively. This phenomenon was closely associated with the ripening stage, as contributed by the initial physiochemical differences, ultrastructure alterations, and moisture distribution. In addition, lower maturity suffered more severe browning, primarily due to the enzymatic and non-enzymatic reactions of phenolics, followed by pigment degradation and the Maillard reaction. Additionally, the PVD process promoted the rupture and transformation of the pectin fractions, also causing browning either directly or indirectly through participation in other chemical reactions. These findings suggest that the appropriate ripening stage of goji berry should be considered as having a significant impact on drying behaviors and quality attributes.
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Lycium , Lycium/química , VacioRESUMEN
Vacuum steam pulsed blanching (VSPB) was employed as a novel blanching technology on Cornus officinalis to soften the tissue for subsequent coring and dehydration. The current work aims to explore its effect on mass transfer behavior, PPO inactivation, drying characteristics, physicochemical properties, antioxidant capacity, and microstructure of C. officinalis. Results showed that VSPB increased water loss, decreased solid gain, and increased weight reduction with increased blanching cycles. Besides, VSPB significantly changed physical properties and extensively reduced drying time which was attributed to the cell wall components dissolving and cell turgor pressure decreasing, also verified by observing microstructure alteration. PPO was completely denatured after blanching in 6 cycles, but phenolic compounds were still diffused or degraded. Notably, the content of flavonoids and antioxidant capacity significantly increased compared to fresh samples probably due to increased extractability caused by the disrupting cell structure. Besides, the carotenoids and ascorbic acid could be well preserved.
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Cornus , Vapor , Antioxidantes/química , Vacio , Agua/química , Desecación/métodosRESUMEN
Based on the concept of circular economy, citrus peel was considered a valuable source of bioactive compounds for high-value foods. Electrohydrodynamic (EHD) drying is a novel technology appropriated for the dehydration of heat-sensitive products such as citrus peel. In current work, EHD drying of citrus peel was performed based on alternating current (AC) or direct current (DC) sources at various voltage levels (9, 18, 27, 36, and 45 kV). The effect of EHD on drying characteristics, water retention capacity, enzyme inactivation, phytochemical contents (phenolic compounds and carotenoids), and volatile compounds of citrus peel were evaluated and compared. Results showed that the drying time in the AC electric field was shorter compared to DC electric field at the same applied voltages due to the polarization layer formed by unipolar charges. The applied voltage determined electric field strength as well as the degree of tissue collapse and cell membrane rupture. EHD elucidated the transformation and degradation of phytochemicals including phenolic compounds, carotenoids, and volatile composition in proportion to the applied voltage. The findings indicate that EHD drying with AC improves drying behaviors, inactivates enzymes, and retains the phytochemical properties of citrus peel.
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Citrus sinensis , Citrus , Citrus sinensis/química , Citrus/química , Extractos Vegetales/química , Carotenoides , Fenoles , FitoquímicosRESUMEN
Photocatalytic CO2 reduction is one of the most cost-effective and environmentally friendly techniques of converting CO2 into high-value compounds and/or fuels. However, the performance of most current photocatalytic CO2 reduction catalysts is less than satisfactory for practical applications. Here, we synthesized a heterogeneous structure by integrating Cu2O and a porphyrin hydrogen-bonded organic framework (PFC-45), which was then fabricated into a thin-film catalyst on carbolic paper (CP) using a facile electrophoretic deposition technology. With improved electron-hole separation efficiency and visible-light-harvesting ability, this film (PFC-45/Cu2O@CP) significantly enhanced CO2-to-CO photoreduction, exceeding 2.4 and 3.2 times that of PFC-45@CP and PFC-45/Cu2O particles, respectively. Remarkably, PFC-45/Cu2O@CP also exhibited high selectivity (99%) and outstanding activity (11.81 µmol g-1 h-1) for photocatalytic CO2 reduction in pure water without any sacrificial agent. This work demonstrates a new strategy to design photocatalysts for efficient CO2 reduction.
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The poor electrical conductivity of metal-organic frameworks (MOFs) has been a stumbling block for its applications in many important fields. Therefore, exploring a simple and effective strategy to regulate the conductivity of MOFs is highly desired. Herein, anionic guest molecules are incorporated inside the pores of a cationic MOF (PFC-8), which increases its conductivity by five orders of magnitude while maintaining the original porosity. In contrast, the same operation in an isoreticular neutral framework (PFC-9) does not bring such a significant change. Theoretical studies reveal that the guest molecules, stabilized inside pores through electrostatic interaction, play the role of electron donors as do in semiconductors, bringing in an analogous n-type semiconductor mechanism for electron conduction. Therefore, we demonstrate that harnessing electrostatic interaction provides a new way to regulate the conductivity of MOFs without necessarily altering the original porous structure. This strategy would greatly broaden MOFs' application potential in electronic and optoelectronic technologies.
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The Pd(0)-catalyzed tandem intermolecular syn-carbopalladation/asymmetric C-H alkenylation reaction of N-ferrocenyl propiolamides with aryl iodides has been realized, generating planar chiral ferrocene[1,2-d] pyrrolinones in good yields. Through employing BINOL-derived phosphoramidite ligands, up to 95% ee is achieved.
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BACKGROUND: Although localized neuroblastoma has a good prognosis, some cases have undergone treatment failure or recurrence. Apart from biologic features such as MYCN status, we wondered whether some characteristics of growing tumors are prognostic, such as a well-encapsulated mass without infiltration of vital organs. We analyzed the diagnostic utility of image-defined risk factors (IDRFs) to predict successful treatment and prognosis. The overall goal was to achieve maximum cure rates for patients with localized neuroblastoma through a better understanding of clinical characteristics. METHODS: We retrospectively reviewed the images of patients with localized neuroblastoma who were enrolled between June 1998 and December 2012 at a single institution in Shanghai, China. Unequivocal categorization regarding IDRFs was available in 67 patients. IDRF was assessed at diagnosis and after four cycles of neoadjuvant chemotherapy, on average. The median follow-up period was 84 months (range: 48-132 months) after diagnosis. RESULTS: MRI and CT indicated a total of 177 IDRFs in these 67 patients. Logistic regression analysis revealed a highly significant negative correlation between the numbers of IDRFs and the possibility of complete removal of neuroblastoma. Intraspinal extension of the tumor, compression of the trachea, and encasement of the main artery in localized neuroblastoma were predictors for incomplete tumor resection. According to univariate analysis, ≥ 4 IDRFs and intraspinal extension of the tumor were significant indicators of poor prognosis. CONCLUSIONS: The number of IDRFs was useful in predicting surgical outcome and event-free survival. The number of IDRFs should be considered in protocol planning, instead of IDRF presence or absence.
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Neuroblastoma/diagnóstico por imagen , Neuroblastoma/patología , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Neuroblastoma/mortalidad , Neuroblastoma/terapia , Pronóstico , Estudios Retrospectivos , Medición de Riesgo/métodos , Factores de Riesgo , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
BACKGROUND: Tetrahydrobiopterin (BH4) is an essential cofactor of nitric oxide synthases (NOSs) for the synthesis of nitric oxide (NO). BH4 therapy can reverse the disease-related redox disequilibrium observed with BH4 deficiency. However, whether BH4 exerts a protective effect against radiation-induced damage to cardiomyocytes remains unknown. METHODS: Clonogenic assays were performed to determine the effects of X-ray on H9c2 cells with or without BH4 treatment. The contents of lactate dehydrogenase (LDH), superoxide dismutase (SOD), and malondialdehyde (MDA) in H9c2 cells were measured to investigate oxidative stress levels. The cell cycle undergoing radiation with or without BH4 treatment was detected using flow cytometry. The expression levels of proteins in the phosphatidylinositol 3 kinase (PI3K)/protein kinase B (AKT)/P53 signaling pathway, inducible NOS (iNOS), and endothelial NOS (eNOS) were examined using Western blotting. RESULTS: X-ray radiation significantly inhibited the growth of H9c2 cells in a dose-dependent manner, whereas BH4 treatment significantly reduced the X-ray radiation-induced growth inhibition (control group vs. X-ray groups, respectively, P< 0.01). X-ray radiation induced LDH release, apoptosis, and G0/G1 peak accumulation, significantly increasing the level of MDA and the production of NO, and decreased the level of SOD (control group vs. X-ray groups, respectively, P < 0.05 or P < 0.01). By contrast, BH4 treatment can significantly reverse these processes (BH4 treatment groups vs. X-ray groups, P < 0.05 or P < 0.01). BH4 reversed the X-ray radiation-induced expression alterations of apoptosis-related molecules, including B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein, and caspase-3, and molecules of the PI3K/Akt/P53 signaling pathway. BH4 enhanced the production of NO in 2 Gy and 4 Gy radiated groups by upregulating eNOS protein expression and downregulating iNOS protein expression. CONCLUSIONS: BH4 treatment can protect against X-ray-induced cardiomyocyte injury, possibly by recoupling eNOS rather than iNOS. BH4 treatment also decreased oxidative stress in radiated H9c2 cells.