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1.
Thromb Res ; 185: 78-84, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31778944

RESUMO

INTRODUCTION: Therapeutic plasma exchange (TPE) is mainstay therapy for thrombotic thrombocytopenic purpura (TTP). However, it remains controversial if ABO type influences diagnosis or time to remission. MATERIALS AND METHODS: We investigated if ABO type influences length of TPE regimen in TTP patients with ADAMTS13 deficiency at our institution. Seventy out of 71 patients with suspected TTP who had ADAMTS13 activity measured were included. ADAMTS13 activity <10% defined those with idiopathic/acquired TTP (41/70). RESULTS: We found that among patients with ADAMTS13 deficiency, non-O patients required a significantly greater number of TPE (NoP) compared to O patients (p = 0.039). Additionally, patients with ADAMTS13 deficiency regardless of ABO type needed more TPE to achieve platelet recovery compared to those patients without deficiency (p = 0.00002). In regard to other variables that may affect response to therapy in TTP patients, we found no association between obesity and NoP; however, obesity rate was higher among ADAMTS13 deficient patients compared to overall obesity rate of our regional general population. Likewise, were found that blood group O did not occur with greater frequency in our cohort. CONCLUSIONS: Our data indicates that ABO may affect the NoP patients required for disease remission. We found that non-O patients needed more procedures to overcome their disease. Further work with greater number of patients will be needed to determine if specific non-O blood types require more procedures to recover their platelet count.

2.
Anal Chem ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31756083

RESUMO

This study for the first time, predicted oxidative stability in camellia oils by partial least squares (PLS) built with proton nuclear magnetic resonance (1H NMR) and α-tocopherol content. The prediction models were established by the PLS method. Outlier detection, latent variables (LVs) optimization, data pre-processing and important variables selection were applied for models optimizing. All the developed models exhibited good performance as indicated by R2 greater than 0.895, RMSEE, RMSEP lower than 0.322 and 0.307. To verify the contribution of 1H NMR spectra and α-tocopherol for the prediction performance, PLS model with fatty acids composition instead of 1H NMR spectra and with only 1H NMR spectra as input variables were developed respectively. The results showed that the models of 1H NMR data-based were more accurate and precise than fatty acid composition data-based. And the performance of the models was significantly degraded without α-tocopherol as input variables.

3.
Proc Natl Acad Sci U S A ; 116(47): 23437-23443, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31685638

RESUMO

Antibiotic resistance has become one of the major threats to global health. Photodynamic inactivation (PDI) develops little antibiotic resistance; thus, it becomes a promising strategy in the control of bacterial infection. During a PDI process, light-induced reactive oxygen species (ROS) damage the membrane components, leading to the membrane rupture and bacteria death. Due to the short half-life and reaction radius of ROS, achieving the cell-membrane intercalation of photosensitizers is a key challenge for PDI of bacteria. In this work, a tetraphenylethylene-based discrete organoplatinum(II) metallacycle (1) acts as a photosensitizer with aggregation-induced emission. It self-assembles with a transacting activator of transduction (TAT) peptide-decorated virus coat protein (2) through electrostatic interactions. This assembly (3) exhibits both ROS generation and strong membrane-intercalating ability, resulting in significantly enhanced PDI efficiency against bacteria. By intercalating in the bacterial cell membrane or entering the bacteria, assembly 3 decreases the survival rate of gram-negative Escherichia coli to nearly zero and that of gram-positive Staphylococcus aureus to ∼30% upon light irradiation. This study has wide implications from the generation of multifunctional nanomaterials to the control of bacterial infection, especially for gram-negative bacteria.

4.
J Exp Clin Cancer Res ; 38(1): 443, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31666112

RESUMO

In the original publication of this article [1], the author would like to revise Figure 4.

5.
Neuroscience ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31698021

RESUMO

An important pathology in Parkinson's disease (PD) is the earlier and more severe degeneration of noradrenergic neurons in the locus coeruleus (LC) than dopaminergic neurons in the substantia nigra. However, the basis of such selective vulnerability to insults remains obscure. Using noradrenergic and dopaminergic cell lines, as well as primary neuronal cultures from rat LC and ventral mesencephalon (VM), the present study compared oxidative DNA damage response markers after exposure of these cells to hydrogen peroxide (H2O2). The results showed that H2O2 treatment resulted in more severe cell death in noradrenergic cell lines SK-N-BE(2)-M17 and PC12 than dopaminergic MN9D cells. Furthermore, there were higher levels of oxidative DNA damage response markers in noradrenergic cells and primary neuronal cultures from the LC than dopaminergic cells and primary cultures from the VM. It included increased tail moments and tail lengths in Comet assay, and increased protein levels of phosphor-p53 and γ-H2AX after treatments with H2O2. Consistent with these measurements, exposure of SK-N-BE(2)-M17 cells to H2O2 resulted in higher levels of reactive oxygen species (ROS). Further experiments showed that exposure of SK-N-BE(2)-M17 cells to H2O2 caused an increased level of noradrenergic transporter, reduced protein levels of copper transporter (Ctr1) and 8-oxoGua DNA glycosylase, as well as amplified levels of Cav1.2 and Cav1.3 expression. Taken together, these experiments indicated that noradrenergic neuronal cells seem to be more vulnerable to oxidative damage than dopaminergic neurons, which may be related to the intrinsic characteristics of noradrenergic neuronal cells.

6.
Cancer Med ; 8(17): 7469-7476, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31605466

RESUMO

Associations between telomere length and cancer risk have been investigated in many epidemiological studies, but the results are controversial. These associations may be biased by reverse causation or confounded by environmental exposures. To avoid potential biases, we used Mendelian randomization method to evaluate whether TL is the causal risk factor for lung cancer. We conducted Mendelian randomization analysis in two published East Asian GWAS studies (7127 cases and 6818 controls). We used both weighted genetic risk score and inverse-variance weighting method to estimate the relationship between TL and lung cancer risk. Nonlinear test also used to detect potential association trends. We observed that increased weight GRS was associated with increased risk of lung cancer (OR = 2.25, 95%CI: 1.81-2.78, P = 1.18 × 10-13 ). In different subtypes, weight GRS was significantly associated with lung adenocarcinoma risk (OR = 2.69, 95% CI: 2.11-3.42, P = 7.20 × 10-16 ); while lung squamous cell carcinoma showed a marginal association (OR = 1.45, 95% CI = 1.01-2.10, P = .047). Nonlinear analysis suggested a log-linear dose-response relationship between increased weight GRS and lung cancer risk. Our results indicated that longer TL increases lung cancer risk. Those biological mechanisms changes caused by long TL may play an important role in lung carcinogenesis.

7.
J Org Chem ; 84(22): 14936-14942, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31608635

RESUMO

A new protocol has been developed for the use of allylic amines as allylating agents in the chiral α-amino acid/palladium-catalyzed asymmetric allylation of α-branched ß-ketoesters, providing highly enantioselective access to all-carbon quaternary stereocenters. Notably, the formation of a primary amine, a secondary amine, or ammonia as a byproduct has little influence on the enantioselectivity for the catalytic asymmetric synthesis of structurally diverse α,α-disubstituted ß-ketoesters.

8.
J Exp Clin Cancer Res ; 38(1): 409, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533816

RESUMO

BACKGROUND: ATPase associated with a variety of cellular activities (AAA ATPase) family members are closely linked to tumor formation and progression. However, their roles in hepatocellular carcinoma (HCC) largely remain unclear. METHODS: Bioinformatic analyses of public databases were used to excavate the potential AAA ATPases that may contribute to HCC, and thyroid hormone receptor interactor 13 (TRIP13) was selected to following researches because of its most prominently differential expression. Western blot, qRT-PCR and immunohistochemistry were used to detect the expression of TRIP13 in HCC tissues, and then the relationship between TRIP13 expression and clinicopathological parameters were evaluated. Finally, its functions and potential mechanisms were investigated through a series gain- and loss-of-function strategies both in vitro and in vivo. RESULTS: TRIP13 was significantly overexpressed in HCC tissues and high level of TRIP13 was closely correlated with a worse clinical outcome. Functionally, elevated TRIP13 facilitated cell proliferation, migration, invasion, and promoted cellular epithelial-mesenchymal transition (EMT) in vitro, while promote tumor growth and lung metastasis in vivo. Mechanistically, TRIP13 interacted with ACTN4 and positively regulated its expression, thus activating the AKT/mTOR pathway to drive tumor progression. Moreover, miR-192-5p served as an upstream regulator of TRIP13 by directly binding to TRIP13 mRNA 3' UTR, which may partially explain the high expression of TRIP13 in HCC. CONCLUSION: Our findings identified TRIP13 as a promising candidate oncogene in HCC, and TRIP13 induced cell migration, invasion and metastasis of HCC through the AKT/mTOR signaling via interacting with ACTN4.

9.
Neurochem Int ; 131: 104549, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31539561

RESUMO

As a classic neurotransmitter in the brain, norepinephrine (NE) also is an important modulator to other neuronal systems. Using primary cultures from rat ventral mesencephalon (VM) and dopaminergic cell line MN9D, the present study examined the neuroprotective effects of NE and its effects on the expression of tyrosine hydroxylase (TH). The results showed that NE protected both VM cultures and MN9D cells against 6-hydroxydopamine-caused apoptosis, with possible involvement of adrenal receptors. In addition, treatment with NE upregulated TH protein levels in dose- and time-dependent manner. Further experiments to investigate the potential mechanisms underlying this NE-induced upregulation of TH demonstrated a marked increase in protein levels of the brain-derived neurotrophic factor (BDNF) and the phosphorylated extracellular signal-regulated protein kinase 1 and 2 (pERK1/2) in VM cultures treated with NE. In MN9D cells, a significantly increase of TH and pERK1/2 protein levels were observed after their transfection with BDNF cDNA or exposure to BDNF peptides. Treatment of VM cultures with K252a, an antagonist of the tropomyosin-related kinase B, blocked the upregulatory effects of NE on TH, BDNF and pERK1/2. Administration of MEK1 & MEK2 inhibitors also reversed NE-induced upregulation of TH and pERK1/2. Moreover, ChIP assay showed that treatment with NE or BDNF increased H4 acetylation in the TH promoter. These results suggest that the neuroprotection and modulation of NE on dopaminergic neurons are mediated via BDNF and MAPK/ERK pathways, as well as through epigenetic histone modification, which may have implications for the improvement of therapeutic strategies for Parkinson's disease.

10.
Mol Biol Rep ; 46(5): 4675-4684, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31529342

RESUMO

The purpose of this study was to test the hypothesis that different cytokine profiles may exist in the follicular fluid of endometriosis (EM) patients undergoing in vitro fertilization (IVF), as these differences may provide insights into the pathogenesis of the disease. This was a cross-sectional study conducted at the reproductive center of a medical university hospital. The study included 49 patients receiving IVF. 20 infertile women with proven EM and 29 women without diagnosed EM (control group) were evaluated. Follicular fluid (FF) and serum were collected at the time of follicle aspiration and the concentrations of 38 cytokines were determined by multiplexed immunoassay. The results indicated that the levels of IL-4, IL-13, IL-3 and IL-1α were significantly increased in the FF of women with EM, while levels of IFN-γ, IL-17A, MDC and MIP-1α were decreased compared with in the control subjects. In conclusions, the immune microenvironment of the FF in patients with EM is altered. This may contribute to the pathologic mechanism responsible for the poor outcome of IVF in patients with EM.

11.
Aging (Albany NY) ; 11(16): 6273-6285, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427543

RESUMO

BACKGROUND: In our previous study, kindlin-2 promoted skin wound healing and decreased the permeability of neovascularization during angiogenesis. Herein, we explored the biological function and underlying mechanism of kindlin-2 in cutaneous melanoma. METHODS AND RESULTS: Through a series of in vitro assays, we found that high levels of kindlin-2 promoted migration and invasion of melanoma cells without influencing cell proliferation. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analyses showed that upregulated kindlin-2 promoted the cellular epithelial-mesenchymal transition (EMT). Importantly, we found that melanoma cells overexpressing kindlin-2 promoted angiogenesis and VEGFA secretion in vitro and facilitated tumour growth and lung metastasis in vivo. To unveil the underlying mechanism, we conducted Next-generation sequencing (NGS) and differential expression analyses. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that overlapping differentially expressed genes (DEGs) were primarily enriched in the TGF-ß, mTOR and VEGF signalling pathways. Then, we confirmed that the mTOR/VEGFA pathway was activated during the process of kindlin-2-induced melanoma progression and angiogenesis. Moreover, we demonstrated that kindlin-2 was significantly overexpressed in clinical melanoma samples and that a high level of kindlin-2 predicted a poor prognosis. CONCLUSIONS: Taken together, these findings showed that kindlin-2 promotes angiogenesis and tumour progression via the mTOR/VEGFA pathway.

12.
Gut ; 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31383772

RESUMO

OBJECTIVE: Although a subset of genetic loci have been associated with gastric cancer (GC) risk, the underlying mechanisms are largely unknown. We aimed to identify new susceptibility genes and elucidate their mechanisms in GC development. DESIGN: We conducted a meta-analysis of four genome-wide association studies (GWASs) encompassing 3771 cases and 5426 controls. After targeted sequencing and functional annotation, we performed in vitro and in vivo experiments to confirm the functions of genetic variants and candidate genes. Moreover, we selected 33 promising variants for two-stage replication in 7035 cases and 8323 controls from other five studies. RESULTS: The meta-analysis of GWASs identified three loci at 1q22, 5p13.1 and 10q23.33 associated with GC risk at p<5×10- 8 and replicated seven known loci at p<0.05. At 5p13.1, the risk rs59133000[C] allele enhanced the binding affinity of NF-κB1 (nuclear factor kappa B subunit 1) to the promoter of PRKAA1, resulting in a reduced promoter activity and lower expression. The knockout of PRKAA1 promoted both GC cell proliferation and xenograft tumour growth in nude mice. At 10q23.33, the rs3781266[C] and rs3740365[T] risk alleles in complete linkage disequilibrium disrupted and created, respectively, the binding motifs of POU2F1 and PAX3, resulting in an increased enhancer activity and expression of NOC3L, while the NOC3L knockdown suppressed GC cell growth. Moreover, two new loci at 3q11.2 (OR=1.21, p=4.56×10- 9) and 4q28.1 (OR=1.14, p=3.33×10- 11) were associated with GC risk. CONCLUSION: We identified 12 loci to be associated with GC risk in Chinese populations and deciphered the mechanisms of PRKAA1 at 5p13.1 and NOC3L at 10q23.33 in gastric tumourigenesis.

13.
Org Lett ; 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31418277

RESUMO

An unprecedented aromatic substitution reaction of benzylic ammonium salts has been developed through palladium-catalyzed C-N bond cleavage. A range of primary and secondary amines participated in a palladium-catalyzed aromatic substitution reaction of benzylic ammonium salts, delivering sterically hindered aromatic amines in moderate to excellent yields with extremely high regioselectivity. Preliminary mechanistic studies permitted successful identification of π-benzylpalladium complexes and γ-vinyl allylic amines as key intermediates. This study paves the way for the use of benzylic ammonium salts in the aromatic substitution reactions.

14.
World J Pediatr ; 15(5): 511-515, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377975

RESUMO

BACKGROUND: To describe mumps virus (MuV) used as a vector to express enhanced green fluorescent protein (EGFP) or red fluorescent protein (RFP) genes. METHODS: Molecular cloning technique was applied to establish the cDNA clones of recombinant mumps viruses (rMuVs). rMuVs were recovered based on our reverse genetic system of MuV-S79. The properties of rMuVs were determined by growth curve, plaque assay, fluorescent microscopy and determination of fluorescent intensity. RESULTS: Three recombinant viruses replicated well in Vero cells and similarly as parental rMuV-S79, expressed heterologous genes in high levels, and were genetically stable in at least 15 passages. CONCLUSION: rMuV-S79 is a promising platform to accommodate foreign genes like marker genes, other antigens and immunomodulators for addressing various diseases.

15.
World J Pediatr ; 15(5): 499-505, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31456156

RESUMO

BACKGROUND: Mumps is a common type of respiratory infectious disease caused by mumps virus (MuV), and can be effectively prevented by vaccination. In this study, a reverse genetic system of MuV that can facilitate the rational design of safer, more efficient mumps vaccine candidates is established. METHODS: MuV-S79 cDNA clone was assembled into a full-length plasmid by means of the GeneArt™ High-Order Genetic Assembly System, and was rescued via reverse genetic technology. RT-PCR, sequencing, and immunofluorescence assays were used for rMuV-S79 authentication. Viral replication kinetics and in vivo experimental models were used to evaluate the replication, safety, and immunogenicity of rMuV-S79. RESULTS: A full-length cDNA clone of MuV-S79 in the assembly process was generated by a novel plasmid assemble strategy, and a robust reverse genetic system of MuV-S79 was successfully established. The established rMuV-S79 strain could reach a high virus titer in vitro. The average viral titer of rMuV-S79 in the lung tissues was 2.68 ± 0.14 log10PFU/g lung tissue, and rMuV-S79 group did not induce inflammation in the lung tissues in cotton rats. Neutralizing antibody titers induced by rMuV-S79 were high, long-lasting and could provide complete protection against MuV wild strain challenge. CONCLUSION: We have established a robust reverse genetic system of MuV-S79 which can facilitate the optimization of mumps vaccines. rMuV-S79 rescued could reach a high virus titer and the safety was proven in vivo. It could also provide complete protection against MuV wild strain challenge.

16.
Molecules ; 24(15)2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31390847

RESUMO

Diabetic kidney disease develops in approximately 40% of diabetic patients and is a major cause of chronic kidney diseases (CKD) and end stage kidney disease (ESKD) worldwide. Hydrogen sulfide (H2S), the third gasotransmitter after nitric oxide (NO) and carbon monoxide (CO), is synthesized in nearly all organs, including the kidney. Though studies on H2S regulation of renal physiology and pathophysiology are still in its infancy, emerging evidence shows that H2S production by renal cells is reduced under disease states and H2S donors ameliorate kidney injury. Specifically, aberrant H2S level is implicated in various renal pathological conditions including diabetic nephropathy. This review presents the roles of H2S in diabetic renal disease and the underlying mechanisms for the protective effects of H2S against diabetic renal damage. H2S may serve as fundamental strategies to treat diabetic kidney disease. These H2S treatment modalities include precursors for H2S synthesis, H2S donors, and natural plant-derived compounds. Despite accumulating evidence from experimental studies suggests the potential role of the H2S signaling pathway in the treatment of diabetic nephropathy, these results need further clinical translation. Expanding understanding of H2S in the kidney may be vital to translate H2S to be a novel therapy for diabetic renal disease.

17.
Mol Pharm ; 16(8): 3694-3702, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31268329

RESUMO

Therapeutic goals for metastatic breast cancer, including shrinkage of established metastasis and suppression of movement of tumor cells, are often hard to achieve and remain the main obstacles restricting the antimetastatic efficacy of targeted drug delivery systems (TDDSs). Herein, we proposed an E-selectin-targeting nanoplatform for the systemic treatment of metastatic breast cancer. Versatile functions, including killing the circulating tumor cells, shrinking the established lesions, as well as inhibiting the movement of tumor cells, were integrated into doxorubicin-loaded sialic acid-dextran-octadecanoic acid (SDO) micelles (SDD). The prepared SDD micelles could not only inhibit lung and liver metastasis in the orthotopic 4T1 tumors model, but also decrease the metastatic lesions in the metastatic 4T1 cell model, resulting in 27.33% reduced number of metastatic nodules when compared to those without sialic acid modification. It was found that the good antimetastatic effect of SDD was only partially attributed to its ability on removing metastatic cells and metastases. Most importantly, the blank SDO micelles left in the lesion could further inhibit the cell migration and cell-cell binding. These results suggest that SA-driven TDDS has the potential for specific targeting and effective treatment of cancer metastasis.

18.
Chemistry ; 25(55): 12671-12683, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31283848

RESUMO

The emergence of the rising alliance between aggregation-induced emission (AIE) and electrochemiluminescence (ECL) is defined as aggregation-induced electrochemiluminescence (AIECL). The booming science of AIE has proved to be not only distinguished in luminescent materials but could also inject new possibility into ECL analysis. Especially in the aqueous phase and solid state for hydrophobic materials, AIE helps ECL circumvent the dilemma between substantial emission intensity and biocompatible media. The wide range of analytes makes ECL an overwhelmingly interesting analytical technique. Therefore, AIECL has gained potential in clinical diagnostics, environmental assays, and biomarker detections. This review will focus on introduction of the novel concept of AIECL, current applied luminophores, and related applications developed in recent years.

19.
Lancet Respir Med ; 7(10): 881-891, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31326317

RESUMO

BACKGROUND: Genetic variation has an important role in the development of non-small-cell lung cancer (NSCLC). However, genetic factors for lung cancer have not been fully identified, especially in Chinese populations, which limits the use of existing polygenic risk scores (PRS) to identify subpopulations at high risk of lung cancer for prevention. We therefore aimed to identify novel loci associated with NSCLC risk, and generate a PRS and evaluate its utility and effectiveness in the prediction of lung cancer risk in Chinese populations. METHODS: To systematically identify genetic variants for NSCLC risk, we newly genotyped 19 546 samples from Chinese NSCLC cases and controls from the Nanjing Medical University Global Screening Array Project and did a meta-analysis of genome-wide association studies (GWASs) of 27 120 individuals with NSCLC and 27 355 without NSCLC (13 327 cases and 13 328 controls of Chinese descent as well as 13 793 cases and 14 027 controls of European descent). We then built a PRS for Chinese populations from all reported single-nucleotide polymorphisms that have been reported to be associated with lung cancer risk at genome-wide significance level. We evaluated the utility and effectiveness of the generated PRS in predicting subpopulations at high-risk of lung cancer in an independent prospective cohort of 95 408 individuals from the China Kadoorie Biobank (CKB) with more than 10 years' follow-up. FINDINGS: We identified 19 susceptibility loci to be significantly associated with NSCLC risk at p≤5·0 × 10-8, including six novel loci. When applied to the CKB cohort, the PRS of the risk loci successfully predicted lung cancer incident cases in a dose-response manner in participants at a high genetic risk (top 10%) than those at a low genetic risk (bottom 10%; adjusted hazard ratio 1·96, 95% CI 1·53-2·51; ptrend=2·02 × 10-9). Specially, we observed consistently separated curves of lung cancer events in individuals at low, intermediate, and high genetic risk, respectively, and PRS was an independent effective risk stratification indicator beyond age and smoking pack-years. INTERPRETATION: We have shown for the first time that GWAS-derived PRS can be effectively used in discriminating subpopulations at high risk of lung cancer, who might benefit from a practically feasible PRS-based lung cancer screening programme for precision prevention in Chinese populations. FUNDING: National Natural Science Foundation of China, the Priority Academic Program for the Development of Jiangsu Higher Education Institutions, National Key R&D Program of China, Science Foundation for Distinguished Young Scholars of Jiangsu, and China's Thousand Talents Program.

20.
Nature ; 571(7764): 226-229, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292556

RESUMO

The importance of highly siderophile elements (HSEs; namely, gold, iridium, osmium, palladium, platinum, rhenium, rhodium and ruthenium) in tracking the late accretion stages of planetary formation has long been recognized. However, the precise nature of the Moon's accretional history remains enigmatic. There is a substantial mismatch in the HSE budgets of the Earth and the Moon, with the Earth seeming to have accreted disproportionally more HSEs than the Moon1. Several scenarios have been proposed to explain this conundrum, including the delivery of HSEs to the Earth by a few big impactors1, the accretion of pebble-sized objects on dynamically cold orbits that enhanced the Earth's gravitational focusing factor2, and the 'sawtooth' impact model, with its much reduced impact flux before about 4.10 billion years ago3. However, most of these models assume a high impactor-retention ratio (the fraction of impactor mass retained on the target) for the Moon. Here we perform a series of impact simulations to quantify the impactor-retention ratio, followed by a Monte Carlo procedure considering a monotonically decaying impact flux4, to compute the impactor mass accreted into the lunar crust and mantle over their histories. We find that the average impactor-retention ratio for the Moon's entire impact history is about three times lower than previously estimated1,3. Our results indicate that, to match the HSE budgets of the lunar crust and mantle5,6, the retention of HSEs should have started 4.35 billion years ago, when most of the lunar magma ocean was solidified7,8. Mass accreted before this time must have lost its HSEs to the lunar core, presumably during lunar mantle crystallization9. The combination of a low impactor-retention ratio and a late retention of HSEs in the lunar mantle provides a realistic explanation for the apparent deficit of the Moon's late-accreted mass relative to that of the Earth.

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