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Angelman syndrome (AS) is an autosomal dominant neurodevelopmental genetic disease with maternal imprint, which is associated with the presence of the abnormal chromosome 15q11-q13, and the loss of maternal specific expression of ubiquitin-protein ligase E3A (UBE3A). The expression levels of UBE3A depend on the parental origin and exhibit tissue specificity. In normal brain tissues, the maternal UBE3A gene is actively expressed, whereas the paternal UBE3A gene is not. In total, ~85% of pediatric patients with AS present with epilepsy within their 3rd year of life. This condition is usually difficult to control with medical treatment. An 8-year-old female visited the Affiliated Hospital of Jining Medical University due to frequent epilepsy. Her clinical manifestations included specific facial features, moderate mental retardation and frequent seizures. It was interesting to note that her 15-year-old sister exhibited similar clinical manifestations to those of AS. The results of the electroencephalogram and the imaging examinations were also in line with the characteristics of AS. In order to further clarify the diagnosis, all the suspected genes in her sister and in their parents were sequenced. The multiplex ligation-dependent probe amplification project of the Angel/chubby and copy number variation (CNV) sequencing were assessed concomitantly to identify the pathogenic genes responsible for the development of AS. The latter occurs due to the missense mutation c.1146T>G, which results in asparagine replacement by lysine at position 382 (p.Asn382Lys) in exon 7. This amino acid change affects the normal expression of UBE3A; the mutation is a novel mutation, which, to the best of our knowledge, has not been previously reported. Relevant large fragments of mutations and methylation abnormalities were not found in the associated genes. The data further revealed absence of 25-bp repeat mutations at the shear mutation site of exon 1 of the small nuclear ribonucleoprotein polypeptide N gene in the subjects examined. No suspected CNV was found following analysis.
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We have presented a unique example of dehydrogenative acylation of enamides with aldehydes enabled by an earth-abundant iron catalyst. The protocol provides the straightforward access to valuable ß-ketoenamides with ample substrate scope and excellent functional group tolerance. Notably, distinct C-H acylation of enamide rather than at N-H moiety site occurs with absolute Z-selectivity was observed. Late-stage modifications of complex molecules and versatile synthetic utility of ß-ketoenamides further highlight the practicability of this transformation.
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(1) Background: Upland cotton (Gossypium hirsutum L.) is the most important natural fiber worldwide, and it is extensively planted and plentifully used in the textile industry. Major cotton planting regions are frequently affected by abiotic stress, especially drought stress. Drought resistance is a complex, quantitative trait. A genome-wide association study (GWAS) constitutes an efficient method for dissecting the genetic architecture of complex traits. In this study, the drought resistance of a population of 316 upland cotton accessions was studied via GWAS. (2) Methods: GWAS methodology was employed to identify relationships between molecular markers or candidate genes and phenotypes of interest. (3) Results: A total of 8, 3, and 6 SNPs were associated with the euphylla wilting score (EWS), cotyledon wilting score (CWS), and leaf temperature (LT), respectively, based on a general linear model and a factored spectrally transformed linear mixed model. For these traits, 7 QTLs were found, of which 2 each were located on chromosomes A05, A11, and D03, and of which 1 was located on chromosome A01. Importantly, in the candidate regions WRKY70, GhCIPK6, SnRK2.6, and NET1A, which are involved in the response to abscisic acid (ABA), the mitogen-activated protein kinase (MAPK) signaling pathway and the calcium transduction pathway were identified in upland cotton at the seedling stage under drought stress according to annotation information and linkage disequilibrium (LD) block analysis. Moreover, RNA sequencing analysis showed that WRKY70, GhCIPK6, SnRK2.6, and NET1A were induced by drought stress, and the expression of these genes was significantly different between normal and drought stress conditions. (4) Conclusions: The present study should provide some genomic resources for drought resistance in upland cotton. Moreover, the germplasm of the different phenotypes, the detected SNPs and, the potential candidate genes will be helpful for molecular marker-assisted breeding studies about increased drought resistance in upland cotton.
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Gossypium/genética , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Plantones/genética , Adaptación Fisiológica , Sequías , Regulación de la Expresión Génica de las Plantas , Estudio de Asociación del Genoma Completo , Gossypium/fisiología , Desequilibrio de Ligamiento , Plantones/fisiología , Estrés FisiológicoRESUMEN
Cell division cycle associated 7 like (CDCA7L) belongs to the JPO protein family, recently identified as a target gene of cMyc and is frequently dysregulated in multiple cancers. However, to the best of our knowledge, no studies to date have been carried out to investigate the functions of CDCA7L in glioma. Thus, in this study, the expression level of CDCA7L and its association with the prognosis in glioma were detected through the TCGA database. The mRNA expression levels of CDCA7L in glioblastoma (GBM) tissues and normal brain tissues were detected by RTqPCR and western blot analysis. To explore the role of CDCA7L in glioma, CDCA7L siRNA was constructed and transfected into U87 glioma cells. The expression levels of CDCA7L and cyclin D1 (CCND1) in glioma U87 cells following transfection with CDCA7L siRNA were measured by RTqPCR and western blot analysis. CCK8, colony formation, EdU and Transwell assays were used to measure the effects of CDCA7L on U87 cell proliferation, and flow cytometry was used to monitor the changes in the cell cycle following transfection with CDCA7L siRNA. Xenograft tumors were examined in vivo for the carcinogenic effects, as well as the mechanisms and prognostic value of CDCA7L in glioma tissues. The results revealed that CDCA7L was highly expressed in human GBM tissues, and a high expression of CDCA7L was associated with a poor prognosis of glioma patients through the TCGA database. We demonstrated that CDCA7L was highly expressed in human GBM tissues and 3 glioma cell lines. The downregulation CDCA7L expression significantly inhibited the proliferation and colony formation ability of U87 cells by blocking cell cycle progression in the G0/G1 phase. In addition, we found that the mRNA and protein levels of CCND1 were markedly decreased following transfection with CDCA7L siRNA compared with NC siRNA in vitro. The downregulation CDCA7L expression reduced the number of invading cells. Consistent with the results of the in vitro assays, the xenograft assay, immunohistochemistry (IHC) assay and western blot analysis demonstrated that, in response to CDCA7L inhibition, tumor growth was inhibited, Ki67 and CCND1 expression levels were decreased in vivo. On the whole, the results of the current study indicate that CDCA7L is highly expressed in human glioma tissues and that a high CDCA7L expression predicts a poor prognosis of glioma patients. CDCA7L promotes glioma U87 cell growth through CCND1.
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Neoplasias Encefálicas/genética , Proliferación Celular , Ciclina D1/genética , Glioblastoma/genética , Proteínas Represoras/metabolismo , Animales , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/fisiopatología , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Glioblastoma/metabolismo , Glioblastoma/fisiopatología , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Pronóstico , Proteínas Represoras/genética , Proteínas Represoras/fisiología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Distal aminoalkyl-substituted quinones have been efficiently prepared through silver-catalyzed site-selective deconstruction and C-C bond transformation of unstrained N-acylated cyclic amines. This method enjoys mild reaction conditions, high selectivity, a broad scope of substrates, and a low catalytic loading of silver. This strategy can also be applied to the modification of peptides bearing cyclic amine residues.
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Maple syrup urine disease (MSUD) is a rare autosomal recessive metabolic disorder caused by mutations in genes that encode subunits of the branchedchain αketoacid dehydrogenase (BCKD) complex. Impairment of the BCKD complex results in an abnormal accumulation of branchedchain amino acids and their corresponding branchedchain keto acids in the blood and cerebrospinal fluid, which are neurovirulent and may become lifethreatening. An 11dayold boy was admitted to the hospital with paroxysmal spasticity of lower extremities. Of note, his 10yearold sister presented similar symptoms during the neonatal period, and her condition was diagnosed as MSUD when she was 1.5 years old. Genetic screening was performed, and the boy and his sister exhibited two novel compound heterozygous mutations in the branched chain keto acid dehydrogenase E1 subunit ß (BCKDHB) gene: A substitution from guanine to adenine in the coding region at position 1,076 (c.1,076G>A) in exon 10 and a deletion of a thymine at position 705 (c.705delT) in exon 6. The missense mutation c.1076G>A results in an amino acid substitution from arginine to lysine at position 359 (p.Arg359Lys), whereas the mutation c.705delT results in the replacement of a cysteine at position 235 with a stop codon (p.Cys235Ter). Neither of the BCKDHB alleles in the compound heterozygote patients is able to generate normal E1ß subunits, resulting in a possible impairment of the activity of the BCKD complex. In the present study, it was hypothesized that the two novel heterozygous mutations in the BCKDHB gene found in the Chinese family may be responsible for the phenotype of the two siblings with MSUD.
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3-Metil-2-Oxobutanoato Deshidrogenasa (Lipoamida)/genética , Extremidad Inferior , Enfermedad de la Orina de Jarabe de Arce/genética , Hermanos , Alelos , Sustitución de Aminoácidos , Aminoácidos de Cadena Ramificada , Pueblo Asiatico , Secuencia de Bases , Encefalopatías , Niño , Electroencefalografía/métodos , Exones , Femenino , Pruebas Genéticas , Heterocigoto , Humanos , Lactante , Extremidad Inferior/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Enfermedad de la Orina de Jarabe de Arce/diagnóstico por imagen , Mutación Missense , Linaje , FenotipoRESUMEN
BACKGROUND: Control of snail intermediate hosts has been proved to be a fast and efficient approach for interrupting the transmission of schistosomiasis. Some plant extracts have shown obvious molluscicidal activity, and a new compound Luo-Wei, also named tea-seed distilled saponin (TDS), was developed based on the saponins extracted from Camellia oleifera seeds. We aimed to test the molluscicidal activity of 4% TDS against the intermediate host snails in China and Egypt, and evaluate its environmental safety to non-target organisms. METHODS: In the laboratory, Oncomelania hupensis, Biomphalaria alexandrina and Bulinus truncatus were exposed to 4% TDS, and the median lethal concentration (LC50) was estimated at 24, 48 and 72 h. In the field, snail mortalities were assessed 1, 2, 3 and 7 d post-immersion with 2.5 g/m3 4% TDS and 1, 3, 7 and 15 d post-spraying with 5 g/m2 4% TDS. In addition, the acute toxicity of 4% TDS to Japanese quail (Coturnix japonica), zebrafish (Brachydanio rerio) and freshwater shrimp (Macrobrachium nipponense) was assessed by estimations of LC50 or median lethal dose (LD50). RESULTS: In the laboratory, the LC50 values of 4% TDS for O. hupensis were 0.701, 0.371 and 0.33 mg/L at 24, 48 and 72 h, respectively, and 4% TDS showed a 1.975 mg/L [corrected] 24 h LC50 against B. alexandrina, and a 1.396 mg/L 24 h LC50 against B. truncatus. Across all study regions, the pooled mortalities of O. hupensis were 72, 86, 94 and 98% at 1, 2, 3 and 7 d, following field immersion of 4% TDS at a dose of 2.5 g/m3, and were 69, 77, 85 and 88% at 1, 3, 7 and 15 d, following field spraying at 5 g/m2, respectively. 4% TDS had moderate toxicity to Japanese quail (7 d LD50 > 60 mg/kg) and to shrimp (96 h LC50 = 6.28 mg/L; 95% CI: 3.53-11.2 mg/L), whereas its toxicity to zebrafish was high (96 h LC50 = 0.15 mg/L; 95% CI: 0.14-0.17 mg/L). CONCLUSIONS: 4% TDS is active against O. hupensis, B. alexandrina and B. truncatus under laboratory and field conditions, and it may be a candidate molluscicide of plant origin.
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Moluscocidas/administración & dosificación , Moluscocidas/toxicidad , Schistosoma/efectos de los fármacos , Caracoles/efectos de los fármacos , Caracoles/parasitología , Animales , Biomphalaria , Bulinus , China , Egipto , Dosificación Letal Mediana , Extractos Vegetales , Codorniz , Esquistosomiasis/prevención & control , Pruebas de ToxicidadRESUMEN
Synthetically versatile anthranils as a bifunctional amino source have been employed for the first time to enable direct amination on unactivated C(sp3)-H bonds of thioamides under Cp*CoIII catalysis. The excellent site-selectivity on primary C(sp3)-H bonds is observed for a diverse array of thioamides with high functional group tolerance. Further applicability of the products is also highlighted through a series of interesting synthetic elaborations.
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BACKGROUND: In multiple cancers, long non-coding RNA small nucleolar RNA host gene 20 (lncRNA SNHG20) is generally dysregulated. In the present study, both the biological role and clinicopathological value of lncRNA SNHG20 in glioma are explored. METHODS: Real-time PCR was employed to determine lncRNA SNHG20 expression in glioma patients. The prognostic role of expression of lncRNA SNHG20 was evaluated in a retrospective cohort study. In addition, the association between lncRNA SNHG20 expression and the clinicopathological features of glioma patients, such as tumor recurrence, survival status, follow-up time, WHO grade, resection extent, tumor location, Karnofsky performance scale score, cystic change, tumor size, gender and age, was discussed. By constructing and transfecting siRNAs that targeted lncRNA SNHG20 into the glioma U87 cells, the effects of lncRNA SNHG20 on the proliferation and cell cycle of U87 cells were assessed through cell counting kit-8, colony formation and cell cycle assays, respectively. In addition, Western blot and real-time PCR measured the expression levels of P21 and CCNA1 in U87 cells after being transfected with SNHG20 siRNA. RESULTS: Our results suggested the high expression of lncRNA SNHG20 in human glioma tissues compared with normal brain tissues, which was related to recurrence-free survival and poor overall survival in glioma patients. According to the existing retrospective cohort study, high lncRNA SNHG20 expression was associated with tumor size, extent of resection, WHO grade, follow-up time, survival status and recurrence. Besides, knocking down the expression of lncRNA SNHG20 could inhibit the proliferation and colony formation abilities of glioma U87 cells through cell cycle arrest. Consequently, the expression of CCNA1 was inhibited, and the expression of P21 was up-regulated in U87 cells. CONCLUSION: A high lncRNA SNHG20 expression level predicts the poor prognosis for glioma patients. Moreover, lncRNA SNHG20 can promote glioma proliferation through silencing P21 and thus lncRNA SNHG20 is an independent potential prognostic biomarker for glioma patients.
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An efficient cobalt-catalyzed ring-opening reaction of bench-stable 1,2-oxazetidines with heteroarenes was unprecedentedly developed. The sustainable Cp *Co(III) catalyst enables a distinctive merger of C-H activation with concomitant N-O and C-C cleavages of 1,2-oxazetidine, leading to site-selective C-H aminomethylation and hydroxymethylation of heteroaromatic compounds containing a broad range of functional groups. Preliminary control experiments unravel some essential mechanistic features of this one-pot transformation.
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This study was established to evaluate the diagnostic value of ultrasonography in screening colorectal polyps in children and to discuss the necessity of colonic preparation before an ultrasonic examination.In this study, 288 children with colorectal polyps managed at our hospital between January 2007 and December 2016 were retrospectively reviewed. All patients were examined before and after basic colon preparation. The colorectal polyps were confirmed by colonoscopy/laparotomy and histopathology. Among all 288 patients, solitary polyps were identified in 278 patients (96.52%), and multiple polyps were identified in 10 patients (43 polyps) (3.48%) by colonoscopy/laparotomy and histopathology.By ultrasonic examination, 264 cases (264/278) were detected as solitary polyp and 9 cases (9/10) as multiple polyps (31 polyps). In 278 solitary polyps, 180 (64.74%) were detected by ultrasonic examination without a colon preparation. Following glycerine enema (10-20âmL) treatment, 264 (94.96%) cases were detected by ultrasonic examination. The sensitivity and specificity of ultrasonography with glycerine enema for the detection of colorectal polyps were 94.96% and 100%, respectively. Colon preparation significantly increased the proportion of polyps identified by ultrasonography (Pâ<â.0001), as well as the diagnostic rate of polyps in rectum, sigmoid colon and descending colon (Pâ<â.05).Ultrasonography can be the primary diagnostic method for screening colorectal polyps in children on the strength of its safety, validity, and accuracy. Basic colon preparation with glycerine enema is recommended for children, which enable the detection of intraluminal lesions before ultrasonic examination.
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Catárticos/uso terapéutico , Colon/diagnóstico por imagen , Pólipos del Colon , Neoplasias Colorrectales , Recto/diagnóstico por imagen , Ultrasonografía/métodos , Biopsia/métodos , Niño , China , Colon/patología , Pólipos del Colon/diagnóstico , Pólipos del Colon/patología , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Precisión de la Medición Dimensional , Femenino , Humanos , Laparotomía/métodos , Masculino , Recto/patología , Reproducibilidad de los Resultados , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Objectives: TP53 is an important tumor suppressor gene to maintain genomic integrity, and its mutations increase the susceptibility to oral carcinoma. Previous published studies have reported the relation of TP53 codon 72 polymorphism with the risk of oral carcinoma, but the results remain controversial and inconclusive. Methods: We therefore utilized meta-analysis based on a comprehensive search in PubMed, EMBASE, and Google of Scholar databases up to August 19, 2017. Results: Total 3,525 cases and 3,712 controls from 21 case-control studies were selected. We found no significant association between TP53 codon 72 polymorphism and oral carcinoma susceptibility in all genetic contrast models, including subgroup analysis based on control source and ethnicity. Furthermore, TP53 codon 72 polymorphism was not significant associated with oral carcinoma susceptibility in tobacco or alcohol use, and HPV infection status. Our results were confirmed by sensitivity analysis and no publication bias was found. Conclusions: Taken together, our data indicate that TP53 codon 72 polymorphism is not associated with the susceptibility to oral carcinoma.
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A copper-catalyzed aminoacyloxylation of unactivated alkenes of unsaturated hydrazones is achieved by using various commercially available carboxylic acids as the acyloxylating reagents and di- tert-butyl peroxide (DTBP) as the oxidant. By using this method, a sequence of structurally diversiform acyloxyl-substituted pyrazolines are efficiently synthesized. Significantly, many carboxyl-containing drugs and bioactive molecules with unprotected functional groups are compatible in this reaction.
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A radical-mediated oxidative cross-coupling of readily accessible α-alkylated styrenes with 1,3-dicarbonyl compounds utilizing a combination of Cu(OAc)2 and air as a catalytic system is described. Rather than requiring α-halocarbonyl compounds, this efficient approach enables direct installation of tertiary functionalized alkyl motifs to olefins with simple carbonyl derivatives. The novel protocol is characterized with high allylic selectivities via a competing ß-H elimination. Both radical-clock and -trapping experiments provided clear-cut evidence for the intermediacy of an α-keto carbon-centered radical.
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LncRNA actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1) is often dysregulated in cancer. We performed this meta-analysis to clarify the usefulness of AFAP1-AS1 as a prognostic marker in malignant tumors. The PubMed, Medline, OVID, Cochrane Library, and Web of Science databases were searched from inception to Augest 7, 2017. Sixteen studies with a total of 1,386 patients were included in the study. The pooled hazard ratio (HR) suggested high AFAP1-AS1 expression correlated with poor overall survival (OS) (HR = 1.98, 95% confidence interval (CI): 1.71-2.28), disease-free survival (DFS) (HR = 1.54, 95% CI: 1.22-1.95), and progression-free survival (PFS) (HR = 2.17, 95% CI:1.64-2.88) in cancer patients, without obvious heterogeneity. High AFAP1-AS1 expression also correlated with larger tumor size (odds ratio (OR) = 2.04, 95% CI: 1.54-2.72), advanced tumor stage (OR=2.35, 95% CI: 1.70-3.26), poor histological grade (OR =1.39, 95% CI: 1.02-1.90), lymph node metastasis (OR = 2.71, 95% CI: 1.98-3.72) and distant metastasis (OR = 2.96, 95% CI: 2.03-4.32). Thus high AFAP1-AS1 expression is predictive of poor OS, DFS, PFS, lymph node metastasis, distant metastasis, histological grade, larger tumor size and tumor stage, which suggests high AFAP1-AS1 expression may serve as a novel biomarker of poor prognosis in cancer.
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A novel and facile approach to vicinal oxycyanation and aminocyanation of internal unactivated alkenes is developed. This method utilizes the dichotomous reactivity of iminoxyl radical derived from the initiation of ß,γ- and γ,δ-unsaturated ketoximes to provide the general difunctionalization of internal alkenes using tert-butyl hydroperoxide (TBHP) as the environmentally friendly oxidant, CuCN as the commercially available cyanating reagent, and pentamethyldiethylenetriamine (PMDETA) as the ligand. By using this protocol, a series of useful cyano-featured isoxazolines and cyclic nitrones were efficiently prepared.
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OBJECTIVES: To analyse the effect of dydrogesterone use during pregnancy on uterine fibroids, pregnancy complications, and pregnancy outcome. MATERIAL AND METHODS: In all, 372 pregnant women with uterine fibroids who were treated at the Affiliated Provincial Hospital of Shandong University were included in this study. Thirty-three of these women received dydrogesterone and constituted the treatment group, and the 27 women who were found to have uterine fibroids during the first trimester but did not receive intervention to prevent miscarriage composed the control group. The changes in uterine fibroids before and after pregnancy and the pregnancy complications were recorded; immunohistochemistry was used to detect the expression of progesterone receptor (PR) and proliferation- and apoptosis-related proteins in the uterine fibroid tissue. RESULTS: No significant difference was observed in the change in uterine fibroid volume during pregnancy between the treatment group and the control group (p > 0.05). The percentage of uterine fibroids with red degeneration was lower in the treatment group than in the control group, but the difference was not statistically significant. No significant difference was observed in newborn weight, height, Apgar score, threatened miscarriage, or premature birth, among other characteristics, between the two groups (p > 0.05). Immunohistochemistry showed no significant difference in the expression of PR, cyclinD1, insulin-like growth factor (IGF1), or B-cell lymphoma 2 (Bcl2) between the two groups. CONCLUSIONS: The use of dydrogesterone during pregnancy has no significant effect on uterine fibroids, pregnancy progression, or pregnancy outcomes in pregnant patients with uterine fibroids.
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Aborto Espontáneo/prevención & control , Didrogesterona/farmacología , Leiomioma/fisiopatología , Complicaciones Neoplásicas del Embarazo/fisiopatología , Progestinas/farmacología , Neoplasias Uterinas/fisiopatología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ciclina D1/metabolismo , Didrogesterona/uso terapéutico , Femenino , Humanos , Recién Nacido , Factor I del Crecimiento Similar a la Insulina/metabolismo , Leiomioma/tratamiento farmacológico , Leiomioma/metabolismo , Embarazo , Complicaciones Neoplásicas del Embarazo/tratamiento farmacológico , Complicaciones Neoplásicas del Embarazo/metabolismo , Resultado del Embarazo , Progestinas/uso terapéutico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias Uterinas/tratamiento farmacológico , Neoplasias Uterinas/metabolismoRESUMEN
OBJECTIVE: To investigate the dynamic changes of the epididymal size 1 year after vasectomy. METHODS: Fifty male volunteers received vasoligation. Before and at 1, 2, 3, 6, and 12 months after operation, we measured the size and detected the internal echoes of the epididymis using color Doppler ultrasonography. RESULTS: The bilateral epididymides were both thickened post-operatively in all the 50 cases, with statistically significant differences between the baseline and the 1st month, the 1st and the 2nd month, the 2nd and the 3rd month, or the 3rd and the 6th month after surgery (all P < 0.01), but not between the 6th and the 12th month (P > 0.05). CONCLUSION: Within 6 months after vasectomy, the bilateral epididymides manifested a progressive thickening, but basically restored their balance of secretion-absorption after 6 months.
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Epidídimo/diagnóstico por imagen , Vasectomía , Epidídimo/patología , Epidídimo/fisiología , Humanos , Masculino , Tamaño de los Órganos , Periodo Posoperatorio , Factores de Tiempo , Ultrasonografía Doppler en ColorRESUMEN
Graphene-supported bimetallic nanoparticles are promising nanocatalysts, which can show strong and tunable catalytic activity and selectivity. Herein room-temperature-ionic-liquid-assisted metal sputtering is utilized to synthesize PdAu bimetallic nanoparticles on graphene with bare surface, small size, high surface density and controlled Pd-to-Au ratio. This controllable synthetic approach is green-chemistry compatible and totally free of additives and byproducts. The supported PdAu nanoparticles show excellent catalytic capabilities for both oxidation and reduction reactions, strongly dependent on the Pd-to-Au ratio. A strong correlation among catalytic performance, bimetallic composition and charge redistribution in the PdAu nanoparticles has been demonstrated. The results suggest that sufficient Au d-holes appear to be significant to the catalysis of oxidation reaction, and a metallic Pd surface is critical to the catalysis of reduction reaction. By the present method, the bimetallic combination can be tailored for distinct types of catalytic reactions.