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1.
Food Microbiol ; 93: 103612, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32912584

RESUMO

Cantaloupes have emerged as significant vehicles of widespread foodborne illness outbreaks caused by bacterial pathogens, including Salmonella. The purpose of this study was to investigate the efficiency of Salmonella colonization and internalization in cantaloupes by relevant routes of contamination. Cantaloupe plants (Cucumis melo 'reticulatus') from two cultivars 'Athena' (Eastern) and 'Primo' (Western) were grown from commercial seed. Plants were maintained in the NCSU BSL-3P phytotron greenhouse. Salmonella enterica (a cocktail of cantaloupe-associated outbreak serovars Javiana, Newport, Panama, Poona and Typhimurium) contamination was introduced via blossoms or soil at ca. 4.4 log10 CFU/blossom or 8.4 log10 CFU/root zone, respectively. Cantaloupes were analyzed for Salmonella by enrichment in accordance with modified FDA-BAM methods. Five randomly chosen colonies from each Salmonella-positive sample were typed using the Agilent 2100 bioanalyzer following multiplex PCR. Data were analyzed for prevalence of contamination and serovar predominance in fruit, stems and soil. Of the total cantaloupe fruit harvested from Salmonella-inoculated blossoms (n = 63), 89% (56/63) were externally contaminated and 73% (46/63) had Salmonella internalized into the fruit. Serovar Panama was the most commonly isolated from the surface of fruit while S. Panama and S. Poona were the most prevalent inside the fruit. When soil was inoculated with Salmonella at one day post-transplant, 13% (8/60) of the plants were shown to translocate the organism to the lower stem (ca. 4 cm) by 7 days post-inoculation (dpi). We observed Salmonella persistence in the soil up to 60 dpi with S. Newport being the predominant serovar at 10 and 20 dpi. These data demonstrate that contaminated soil and blossoms can lead to Salmonella internalization into the plant or fruit at a relatively high frequency.

2.
Nat Commun ; 11(1): 5244, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33067423

RESUMO

The protein deacetylase SIRT6 maintains cellular homeostasis through multiple pathways that include the deacetylation of histone H3 and repression of transcription. Prior work suggests that SIRT6 is associated with chromatin and can substantially reduce global levels of H3 acetylation, but how SIRT6 is able to accomplish this feat is unknown. Here, we describe an exquisitely tight interaction between SIRT6 and nucleosome core particles, in which a 2:1 enzyme:nucleosome complex assembles via asymmetric binding with distinct affinities. While both SIRT6 molecules associate with the acidic patch on the nucleosome, we find that the intrinsically disordered SIRT6 C-terminus promotes binding at the higher affinity site through recognition of nucleosomal DNA. Together, multivalent interactions couple productive binding to efficient deacetylation of histones on endogenous chromatin. Unique among histone deacetylases, SIRT6 possesses the intrinsic capacity to tightly interact with nucleosomes for efficient activity.

3.
Methods ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33039573

RESUMO

Single-cell protein abundance is a fundamental type of information to characterize cell states. Due to high cost and technical barriers, however, direct quantification of proteins is difficult. Single-cell RNA sequencing (scRNA-seq) data, serving as a cost-effective substitute of single-cell proteomics, may not accurately reflect protein expression levels due to measurement error, noise, post-transcriptional and translational regulation, etc. The recently emerging single-cell multimodal omics data, e.g. CITE-seq and REAP-seq, can simultaneously profile RNA and protein abundances in single cells, providing labeled data for predictive modeling in a supervised learning framework. Deep neural network-based transfer learning method has been applied to imputation of surface protein abundance from single-cell transcriptomic data. However, it is unclear if the artificial neural network is the best model, and it is desirable to improve the prediction performance (e.g. accuracy, interpretability) of machine learning models. In this paper, we compared several tree-based ensemble learning methods with neural network models, and found that ensemble learning often performed better than neural network, and Random Forest (RF) performed the best overall. Moreover, we used the feature importance scores from RF to interpret biological mechanisms underlying the prediction. Our study demonstrates the effectiveness of ensemble learning for reliable protein abundance prediction using single-cell multimodal omics data, and paves the way for knowledge discovery by mining single-cell multi-omics data in large scale.

4.
Molecules ; 25(19)2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33027947

RESUMO

Phlorotannins are a group of major polyphenol secondary metabolites found only in brown algae and are known for their bioactivities and multiple health benefits. However, they can be oxidized due to external factors and their bioavailability is low due to their low water solubility. In this study, the potential of utilizing nanoencapsulation with polyvinylpyrrolidone (PVP) to improve various activities of phlorotannins was explored. Phlorotannins encapsulated by PVP nanoparticles (PPNPS) with different loading ratios were prepared for characterization. Then, the PPNPS were evaluated for in vitro controlled release of phlorotannin, toxicity and antioxidant activities at the ratio of phlorotannin to PVP 1:8. The results indicated that the PPNPS showed a slow and sustained kinetic release of phlorotannin in simulated gastrointestinal fluids, they were non-toxic to HaCaT keratinocytes and they could reduce the generation of endogenous reactive oxygen species (ROS). Therefore, PPNPS have the potential to be a useful platform for the utilization of phlorotannin in both pharmaceutical and cosmetics industries.

5.
J Exp Bot ; 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33005924

RESUMO

Acyl-CoA: diacylglycerol acyltransferase (DGAT) catalyzes the final committed step in triacylglycerol (TAG) biosynthesis in eukaryotes. In microalgae, the copy number of DGAT genes is extraordinarily expanded and yet the functions of many DGATs remain largely unknown. This study revealed microalgal DGAT can function as lysophosphatidic acyltransferase (LPAAT) both in vitro and in vivo while losing its original function as DGAT. Among the five DGAT encoding genes identified and cloned from the green microalga Haematococcus pluvialis, four encodes HpDGATs that showed TAG synthase activities in yeast for functional complementation analysis, except for one of the type II DGAT encoding genes, i.e., HpDGTT2 gene. The hydrophobic recombinant HpDGTT2 was purified in a soluble form and was revealed to function as a LPAAT via enzymatic assay. Introducing this gene into the green microalga Chlamydomonas reinhardtii led to retarded cellular growth, enlarged cell size and enhanced TAG accumulation, identical to the phenotypes of the transgenic strains with overexpressed CrLPAAT. This study provides a framework for dissecting uncharacterized DGATs, and could pave the way to decrypt the structure-function relationship of this large group of enzymes critical to lipid biosynthesis.

6.
J Ethnopharmacol ; 266: 113397, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32971159

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Atopic dermatitis (AD) is a complex skin disease with highly heterogeneous inflammation, which ranks among the largest component of the nonfatal diseases worldwide. The medications currently used to treat AD primarily include antihistamines, vitamin D and anti-inflammatory drugs, etc. But, the usage of these drugs is usually accompanied by various side-effects. Formononetin (FMN), a natural active ingredient of Astragalus membranaceus (Fisch.) Bunge, decreases the AD relapse rate, reduces recurring severity incidence and resists the inflammation in the initial stage of AD. However, the underlying mechanism of FMN on repressing the development of AD is still unknown. AIM OF THE STUDY: To investigate the potential mechanism of FMN on relieving the initial responses of AD and elucidate its possible therapeutic targets in vivo and in vitro. MATERIALS AND METHODS: A fluorescein isothiocyanate (FITC)-induced mouse model of the initial stage of AD was established in vivo. Human keratinocytes (HaCaT) cells were co-stimulated with tumor necrosis factor alpha (TNF-α) and polyinosinic-polycytidylic acid (Poly(I:C)) in vitro. The production of thymic stromal lymphopoietin (TSLP) and immunoglobulin E (IgE) were detected by enzyme-linked immunosorbnent assay (ELISA). The protein expression was measured through immunohistochemistry and western blotting. The mRNA expression was examined by real-time quantitative polymerase chain reaction (RT-qPCR). The impact of TNF-α-induced protein 3 (TNFAIP3/A20) was reflected using its small interfering RNA (siRNA). The role of G protein-coupled estrogen receptor (GPER) was explored using its agonist (G1), antagonist (G15) or siRNA (siGPER) in vitro. RESULTS: We found that FMN upregulated the expression of A20 protein and mRNA in the initial stage of AD model, especially in the epithelial region of ear tissue, and inhibited the production of TSLP simultaneously. Consistently, FMN significantly upregulated A20 protein and its mRNA expression while reduced TSLP protein and its mRNA expression in vitro, and this effect could be antagonized by A20 siRNA (siA20). Moreover, compared with PPT (ERα agonist) and DPN (ERß agonist), G1 could significantly increase the expression of A20. In addition, compared with MPP (ERα antagonist) and PHTPP (ERß antagonist), G15 could markedly reduce the expression of A20. Furthermore, the effects of FMN on A20 were interfered by siGPER and G15 in vitro and in vivo. CONCLUSIONS: These results demonstrated that FMN attenuated AD by upregulating A20 expression via activation of GPER. This new strategy might have effective therapeutic potential for AD and other inflammatory disorders.

7.
Acta Biomater ; 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32911103

RESUMO

Common events in the clinic, such as uterine curettage or inflammation, may lead to irreversible endometrial damage, often resulting in infertility in women of childbearing age. Currently, tissue engineering has the potential to achieve tissue manipulation, regeneration, and growth, but personalization and precision remain challenges. The application of "3D cell printing" is more in line with the clinical requirements of tissue repair. In this study, a porous grid-type human induced pluripotent stem cell-derived mesenchymal stem cell (hiMSC)-loaded hydrogel scaffold was constructed using a 3D bioprinting device. The 3D-printed hydrogel scaffold provided a permissive in vitro living environment for hiMSCs and significantly increased the survival duration of transplanted hiMSCs when compared with hiMSCs administered locally in vivo. Using an endometrial injury model, we found that hiMSC transplantation can cause early host immune responses (the serological immune response continued for more than 1 month, and the local immune response continued for approximately 1 week). Compared with the sham group, although the regenerative endometrium failed to show full restoration of the normal structure and function of the lining, implantation of the 3D-printed hiMSC-loaded scaffold not only promoted the recovery of the endometrial histomorphology (endometrial tissue and gland regeneration) and the regeneration of endometrial cells (stromal cells and epithelial cells) and endothelial cells but also improved endometrial receptivity functional indicators, namely, pinopode formation and leukemia inhibitory factor and αvß3 expression, which partly restored the embryo implantation and pregnancy maintenance functions of the injured endometrium. These indicators were significantly better in the 3D-printed hiMSC-loaded scaffold group than in the unrepaired (empty) group, the hiMSCs alone group and the 3D scaffold group, and the empty group showed the worst repair results. Our study confirm that the 3D-printed hiMSC-loaded hydrogel scaffold may be a promising material for endometrial repair.

8.
Mol Med Rep ; 22(5): 3621-3628, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32901887

RESUMO

Intervertebral disc degeneration (IDD) is a degenerative disease of the spine originating from the intervertebral disc. MicroRNAs (miRNAs or miRs) are a group of endogenous small non­coding RNAs that act on target genes and play a critical role in numerous biological processes. However, the underlying mechanism of miR­25­3p in IDD remains unclear. Therefore, the present study aimed to explore the role of miR­25­3p in the pathogenesis of IDD. The results demonstrated that miR­25­3p was downregulated in rat degenerative nucleus pulposus (NP) cells and that Bcl­2 interacting mediator of cell death (Bim) was a direct target of miR­25­3p. Next, to investigate the effect of miR­25­3p on normal NP cell proliferation and apoptosis, NP cells were transfected with an miR­25­3p inhibitor, a negative control of miR­25­3p inhibitor, miR­25­3p inhibitor + control­small interference RNA (siRNA) or miR­25­3p inhibitor + Bim­siRNA for 48 h and cell proliferation and apoptosis were then analyzed. The results demonstrated that the miR­25­3p inhibitor could decrease NP cell proliferation and induce cell apoptosis, and these effects were reversed by Bim­siRNA. In addition, an in vitro cell model of IDD was established by subjecting NP cells to 10 ng/ml interleukin (IL)­1ß for 24 h. Further experiments suggested that IL­1ß treatment induced a reduction in NP cell proliferation and an increase in cell apoptosis, which were prevented by the miR­25­3p mimic. All the effects of miR­25­3p mimic on IL­1ß­treated NP cells were significantly reversed by Bim upregulation. These findings suggested that miR­25­3p may be a novel therapeutic target for IDD prevention.

9.
Nat Genet ; 52(10): 1122-1131, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32895551

RESUMO

The human proteome is a major source of therapeutic targets. Recent genetic association analyses of the plasma proteome enable systematic evaluation of the causal consequences of variation in plasma protein levels. Here we estimated the effects of 1,002 proteins on 225 phenotypes using two-sample Mendelian randomization (MR) and colocalization. Of 413 associations supported by evidence from MR, 130 (31.5%) were not supported by results of colocalization analyses, suggesting that genetic confounding due to linkage disequilibrium is widespread in naïve phenome-wide association studies of proteins. Combining MR and colocalization evidence in cis-only analyses, we identified 111 putatively causal effects between 65 proteins and 52 disease-related phenotypes ( https://www.epigraphdb.org/pqtl/ ). Evaluation of data from historic drug development programs showed that target-indication pairs with MR and colocalization support were more likely to be approved, evidencing the value of this approach in identifying and prioritizing potential therapeutic targets.

10.
Ann Neurol ; 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32981134

RESUMO

OBJECTIVE: We conducted a Mendelian randomization (MR) study to disentangle the comparative effects of lipids and apolipoproteins on ischemic stroke. METHODS: Single-nucleotide polymorphisms associated with low- and high-density lipoprotein (LDL and HDL) cholesterol, triglycerides, and apolipoprotein A-I and B (apoA-I and apoB) at the level of genomewide significance (p < 5 × 10-8 ) in the UK Biobank were used as instrumental variables. Summary-level data for ischemic stroke and its subtypes were obtained from the MEGASTROKE consortium with 514,791 individuals (60,341 ischemic stroke cases, and 454,450 non-cases). RESULTS: Increased levels of apoB, LDL cholesterol, and triglycerides were associated with higher risk of any ischemic stroke, large artery stroke, and small vessel stroke in the main and sensitivity univariable MR analyses. In multivariable MR analysis including apoB, LDL cholesterol, and triglycerides in the same model, apoB retained a robust effect (p < 0.05), whereas the estimate for LDL cholesterol was reversed, and that for triglycerides largely attenuated. Decreased levels of apoA-I and HDL cholesterol were robustly associated with increased risk of any ischemic stroke, large artery stroke, and small vessel stroke in all univariable MR analyses, but the association for apoA-I was attenuated to the null after mutual adjustment. INTERPRETATION: The present MR study reveals that apoB is the predominant trait that accounts for the etiological basis of apoB, LDL cholesterol, and triglycerides in relation to ischemic stroke, in particular large artery and small vessel stroke. Whether HDL cholesterol exerts a protective effect on ischemic stroke independent of apoA-I needs further investigation. ANN NEUROL 2020.

11.
Artigo em Inglês | MEDLINE | ID: mdl-32876994

RESUMO

Renal tubular secretion is an active efflux pathway for the kidneys to remove molecules but has never been used to enhance kidney cancer targeting. Herein, we report the first renal tubule-secretable near infrared-emitting fluorophore, indocyanine green (ICG) conjugated with a 2100 Da PEG molecule (ICG-PEG45) and its advantages in hyperfluorescence imaging of kidney cancers, which cannot be achieved with hepatobiliary- and glomerular-clearable ICG. This pathway-dependent targeting of kidney cancer fundamentally arises from the fact that the secretion pathway enabled ICG-PEG45 to be effectively effluxed out of normal proximal tubules through P-glycoprotein transporter while being retained in the kidney cancerous tissues with low P-glycoprotein expression. Tuning elimination pathways and utilizing different efflux kinetics of medical agents in normal and diseased tissues could be a new strategy, in addition to well-known vasculature-based passive and ligand-receptor mediated active targeting, for tackling challenges in disease diagnosis and treatments.

12.
Neurol Sci ; 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895776

RESUMO

Spinal muscular atrophy (SMA) is a type of autosomal recessive genetic disease, which seriously threatens the health and lives of children and adolescents. We attempted to find some genes and mutations related to the onset of SMA. Eighty-three whole-blood samples were collected from 28 core families, including 28 probands with clinically suspected SMA (20 SMA patients, 5 non-SMA children, and 3 patients with unknown etiology) and their parents. The multiplex ligation probe amplification (MLPA) was performed for preliminary diagnosis. The high-throughput sequencing technology was used to conduct the whole-exome sequencing analysis. We analyzed the mutations in adjacent genes of SMN1 gene and the unique mutations that only occurred in SMA patients. According to the MLPA results, 20 probands were regarded as experimental group and 5 non-SMA children as control group. A total of 10 mutations were identified in the adjacent genes of SMN1 gene. GUSBP1 g.[69515863G>A], GUSBP1 g.[69515870C>T], and SMA4 g.[69515738C>A] were the top three most frequent sites. SMA4 g.[69515726A>G] and OCLN c.[818G>T] have not been reported in the existing relevant researches. Seventeen point mutations in the DYNC1H1 gene were only recognized in SMA children, and the top two most common mutations were c.[2869-34A>T] and c.[345-89A>G]; c.[7473+105C>T] was the splicing mutation that might change the mRNA splicing site. The mutations of SMA4 g.[69515726A>G], OCLN c.[818G>T], DYNC1H1 c.[2869-34A>T], DYNC1H1 c.[345-89A>G], and DYNC1H1 c.[7473+105C>T] in the adjacent genes of SMN1 gene and other genes might be related to the onset of SMA.

13.
Cell Death Dis ; 11(9): 751, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32929075

RESUMO

Although ferroptosis has been recognized as a novel antitumoral treatment, high expression of nuclear factor erythroid 2-related factor 2 (NRF2) has been reported to be an antioxidant transcript factor that protects malignant cells from ferroptosis. Previous findings indicated that metallothionein 1D pseudogene (MT1DP), a long noncoding RNA (lncRNA), functioned to aggravate oxidative stress by repressing antioxidation. Here we aimed at assessing whether MT1DP could regulate erastin-induced ferroptosis on non-small cell lung cancer (NSCLC) and elucidating the mechanism. We found that ectopic expression of MT1DP sensitized A549 and H1299 cells to erastin-induced ferroptosis through downregulation of NRF2; in addition, ectopic MT1DP upregulated malondialdehyde (MDA) and reactive oxygen species (ROS) levels, increased intracellular ferrous iron concentration, and reduced glutathione (GSH) levels in cancer cells exposed to erastin, whereas downregulation of MT1DP showed the opposite effect. RNA pulldown assay and dual-luciferase reporter assay confirmed that MT1DP modulated the expression of NRF2 via stabilizing miR-365a-3p. As low solubility of erastin limits its efficient application, we further prepared folate (FA)-modified liposome (FA-LP) nanoparticles for targeted co-delivery of erastin and MT1DP to enhance the bioavailability and the efficiency of the drug/gene combination. Erastin/MT1DP@FA-LPs (E/M@FA-LPs) sensitized erastin-induced ferroptosis with decreased cellular GSH levels and elevated lipid ROS. In vivo analysis showed that E/M@FA-LPs had a favorable therapeutic effect on lung cancer xenografts. In short, our findings identify a novel strategy to elevate erastin-induced ferroptosis in NSCLCs acting through the MT1DP/miR-365a-3p/NRF2 axis.

14.
Dermatol Ther ; : e14263, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32869931

RESUMO

Psoriasis is a chronic, recurrent skin disease requiring long-term management. Agents that repair the skin's barrier function are invaluable additives in topical treatments of psoriasis. This multicenter, randomized, controlled trial evaluated the efficacy and safety of a linoleic acid-ceramide-containing moisturizer (LA-Cer) for mild-to-moderate psoriasis vulgaris. We randomized 178 patients from both northern and southern regions of China into two groups: 81 patients in the control group received mometasone furoate (MF, 0.1%) cream, while MF in combination with LA-Cer was administered to 86 patients in the treatment group for 4 weeks. The LA-Cer-MF group maintained the use of moisturizer after topical glucocorticoid administration. The primary endpoint, Psoriasis Area and Severity Index 50 (PASI 50) response, revealed the superiority of LA-Cer-MF with lower relapse rates at week 8. The use of the LA-Cer-containing moisturizer as maintenance therapy resulted in a continuous improvement in the clinical state in terms of body surface area, PASI, investigators' assessment of skin dryness and desquamation, and Physician Global Assessment of Psoriasis score, and in the patients' quality of life. Thus, the LA-Cer-containing moisturizer is a promising agent to prevent and treat psoriasis as it enhances the therapeutic effect induced by topical glucocorticoids and delays relapse.

15.
Medicine (Baltimore) ; 99(35): e21848, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871908

RESUMO

RATIONALE: Drug-induced pancreatitis (DIP) is a kind of acute pancreatitis with a relatively low incidence. There are many cases of acute pancreatitis (AP) caused by chemotherapeutic agents that have been reported. However, few reports focus on the combination of chemotherapeutic agents that induce acute pancreatitis. This article aims to retrospectively analyze a case of DIP and to explore the relationship between chemotherapeutic agents and acute pancreatitis. PATIENT CONCERNS: Here, we report a 35-year-old Chinese female patient who was diagnosed as acute myeloid leukemia with BCR/ABL expression. After induction chemotherapy of daunorubicin and cytarabine, bone marrow aspiration showed: Acute myeloid leukemia-not relieved (AML-NR). Then the regimen of homoharringtonine, cytarabine and dasatinib was started. The patient developed abdominal pain on the 14th day of chemotherapy. Laboratory tests showed elevated serum amylase (AMY) and lipase (LIPA). Computed tomography (CT) of the abdomen revealed a swollen pancreas with blurred edges and thickened left prerenal fascia. DIAGNOSIS: The patient was diagnosed as DIP by the symptoms of upper abdominal pain and the change of CT images. Other common causes of AP were excluded meanwhile. INTERVENTIONS: The chemotherapy was stopped immediately. And after fasting, fluid infusion and inhibiting the secretion of the pancreas, the symptoms were relieved. OUTCOMES: DIP relapsed when the regimen of aclacinomycin + cytarabine + G-CSF + dasatinib regimen (G-CSF (400ug/day, day 1 to 15), cytarabine (30 mg/day, day 2 to 15), aclacinomycin (20 mg/day, day 2 to 5)and dasatinib (140 mg/day, continuously)) was given, and was recovered after treatment for AP was performed. LESSONS: To choose the best treatment plan for patients, clinicians should raise awareness of DIP, and should know that chemotherapeutic agents can induce pancreatitis and the combination of chemotherapeutic agents may increase the risk of drug-induced pancreatitis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Pancreatite/induzido quimicamente , Adulto , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Dasatinibe/administração & dosagem , Dasatinibe/efeitos adversos , Daunorrubicina/administração & dosagem , Daunorrubicina/efeitos adversos , Feminino , Mepesuccinato de Omacetaxina/administração & dosagem , Mepesuccinato de Omacetaxina/efeitos adversos , Humanos , Pancreatite/diagnóstico por imagem , Tomografia Computadorizada por Raios X
16.
Biochem Biophys Res Commun ; 532(2): 239-243, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-32868072

RESUMO

Pleotropic growth factor, transforming growth factor (TGF)-ß drives the modification and elongation of glycosaminoglycan (GAG) chains on proteoglycans. Hyperelongated GAG chains bind and trap lipoproteins in the intima leading to the formation of atherosclerotic plaques. We have identified that phosphorylation of Smad2 linker region drives GAG chain modification. The identification of an inhibitor of Smad2 linker region phosphorylation and GAG chain modification signifies a potential therapeutic for cardiovascular diseases. Artemisinin renowned for its potent anti-malarial effects possesses a broad range of biological effects. Our aim was to characterise the anti-atherogenic role of artemisinin in vascular smooth muscle cells (VSMCs). We demonstrate that TGF-ß mediated Smad2 linker region phosphorylation and GAG chain elongation was attenuated by artemisinin; however, we observed no effect on VSMC proliferation. Our data demonstrates the potential for artemisinin to be developed as a therapy to inhibit the development of atherosclerosis by prevention of lipid deposition in the vessel wall without affecting the proliferation of VSMCs.

17.
Proc Natl Acad Sci U S A ; 117(39): 24415-24426, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32913049

RESUMO

KRAS mutant lung adenocarcinomas remain intractable for targeted therapies. Genetic interrogation of KRAS downstream effectors, including the MAPK pathway and the interphase CDKs, identified CDK4 and RAF1 as the only targets whose genetic inactivation induces therapeutic responses without causing unacceptable toxicities. Concomitant CDK4 inactivation and RAF1 ablation prevented tumor progression and induced complete regression in 25% of KRAS/p53-driven advanced lung tumors, yet a significant percentage of those tumors that underwent partial regression retained a population of CDK4/RAF1-resistant cells. Characterization of these cells revealed two independent resistance mechanisms implicating hypermethylation of several tumor suppressors and increased PI3K activity. Importantly, these CDK4/RAF1-resistant cells can be pharmacologically controlled. These studies open the door to new therapeutic strategies to treat KRAS mutant lung cancer, including resistant tumors.

18.
Mol Genet Genomic Med ; : e1501, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32959514

RESUMO

BACKGROUND: 21-Hydroxylase deficiency (21-OHD) caused by the CYP21A2 gene mutations is the most common form of congenital adrenal hyperplasia. It is an autosomal recessive disorder that results in defective synthesis of cortisol and aldosterone. The incidences of various CYP21A2 gene mutations and the genotype-phenotype correlations vary among different populations. MATERIALS AND METHODS: The clinical and molecular data of 22 patients were analyzed in this study. All patients were recruited from the neonatal intensive care unit. Locus-specific polymerase chain reaction and Sanger sequencing were applied to identify gene micro-conversions, and multiplex ligation-dependent probe amplification was used to detect large fragment deletions/conversions. Then, the genotypes were categorized in to Null, A, B, C, and D groups to analyze the relationships between genotypes and phenotypes. RESULTS: All 22 patients were classified into classic salt wasting form of 21-OHD. Molecular defects were detected in 44 alleles (100%). Micro-conversion mutation IVS2-13A/C>G (70.5%) is most common in our cohort, followed by large gene deletions and conversions (22.7%). The other mutations present were p.R357 W (4.5%) and E6 Cluster (2.3%). Genotypes of 22 patients (100%) were consistent with the predictive phenotypes. CONCLUSION: In this study, we identified the mutation spectrum of CYP21A2 gene in Chinese patients, especially the younger age cohort in pediatrics. Micro-conversions were the most popular mutations. Moreover, the genotypes and phenotypes were well correlated in this cohort of salt wasting 21-OHD recruited from neonatal intensive care unit.

19.
Circ Cardiovasc Qual Outcomes ; 13(9): e006171, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32867514

RESUMO

BACKGROUND: The Center for Medicare and Medicaid Innovation launched the Bundled Payments for Care Initiative (BPCI) in 2013. Its effect on payments and outcomes for percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) is unknown. METHODS AND RESULTS: We used Medicare inpatient files to identify index admissions for PCI and CABG from 2013 through 2016 at BPCI hospitals and matched control hospitals and difference in differences models to compare the 2 groups. Our primary outcome was the change in standardized Medicare-allowed payments per 90-day episode. Secondary outcomes included changes in patient selection, discharge to postacute care, length of stay, emergency department use, readmissions, and mortality. Forty-two hospitals joined BPCI for PCI and 46 for CABG. There were no differential changes in patient selection between BPCI and control hospitals. Baseline Medicare payments per episode for PCI were $20 164 at BPCI hospitals and $19 955 at control hospitals. For PCI, payments increased at both BPCI and control hospitals during the intervention period, such that there was no significant difference in differences (BPCI hospitals +$673, P=0.048; control hospitals +$551, P=0.022; difference in differences $122, P=0.768). For CABG, payments at both BPCI and control hospitals decreased during the intervention period (BPCI baseline, $36 925, change -$2918, P<0.001; control baseline, $36 877, change -$2618, P<0.001; difference in differences, $300; P=0.730). For both PCI and CABG, BPCI participation was not associated with changes in mortality, readmissions, or length of stay. Among BPCI hospitals, emergency department use differentially increased for patients undergoing PCI and decreased for patients undergoing CABG. CONCLUSIONS: Participation in episode-based payment for PCI and CABG was not associated with changes in patient selection, payments, length of stay, or clinical outcomes.

20.
Theranostics ; 10(21): 9674-9685, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32863953

RESUMO

Adult hippocampal neurogenesis (AHN) deficits contribute to the progression of cognitive impairments during accelerated senescence, with the mechanistic causes poorly understood. Glycogen synthase kinase-3ß (GSK-3ß) is a critical regulator in prenatal neurodevelopment. The present study aims to study whether and how GSK-3ß regulates AHN during the accelerated senescence. Methods: AHN and AHN-dependent cognition and GSK-3ß were evaluated in 3- and 6-month senescence-accelerated mice prone 8 (SAM-P8) and senescence resistant 1 (SAM-R1) mice, respectively. GSK-3ß was selectively overexpressed in wild-type mice using adeno-associated virus, or knocked-out by crossbreeding with GSK-3ß floxed mice in the neural stem cells (NSCs) of Nestin-Cre mice, or pharmacologically inhibited with SB216763 in SAM-P8 mice. AHN was evaluated by BrdU-, DCX-staining and retrovirus-labeling. Results: AHN transiently increased at 3-month, but dramatically dropped at 6-month of age in SAM-P8 mice with a simultaneous activation of GSK-3ß at 3-month. Selective overexpression of GSK-3ß in hippocampal NSCs of wildtype mice induced long-term AHN deficits due to an accelerated depletion of NSC pool, although it transiently increased the proliferation and survival of the newborn neurons. Pharmacologically inhibiting GSK-3ß by SB216763 efficiently preserved AHN and improved contextual memory in 6-month SAM-P8 mice, while conditional knock-out of GSK-3ß in NSCs impaired AHN. Conclusion: Early-stage activation of GSK-3ß in NSCs impairs AHN by accelerating the depletion of NSC pool, and pharmacological inhibition of GSK-3ß is efficient to preserve AHN during the accelerated aging. These results reveal novel mechanisms underlying the AHN impairments during accelerated senescence and provide new targets for pro-neurogenic therapies for related diseases.

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