Dissimilar effects of the hydrophilic carbon dots on the amyloid aggregation of two model proteins and the mechanism discussion.

Many proteins could aggregate into amyloid fibrils under certain conditions. However, the aggregation process and morphology of the fibrils may be significantly different because of the distinct protein structure. In this article, the hydrophilic carbon dots (Lys-CA-CDs) were prepared using lysine (Lys) and citric acid (CA) as reactant under the assistance of a microwave. The dissimilar modulation effect of Lys-CA-CDs on the aggregation process of distinct structure protein was further investigated, where bovine serum albumin (BSA) and hen egg white lysozyme (HEWL) were chosen as model proteins. All results showed that Lys-CA-CDs displayed the contrary influence on the aggregation process of BSA and HEWL. Lys-CA-CDs could induce BSA to aggregate into more wormlike fibrils and inhibit the aggregation of HEWL into hair-like fibrils. The influence on the aggregation process of BSA may be assigned to the increased concentration of BSA around the Lys-CA-CDs caused by their interaction. However, inserting of Lys-CA-CDs into the inner structure of HEWL led to the change of protein secondary structure. The change of secondary structure further made it difficult for HEWL to aggregate into fibrils and Lys-CA-CDs showed the inhibition effect on HEWL aggregation.

A photochemically covalent lock stabilizes aptamer conformation and strengthens its performance for biomedicine.

Aptamers' vast conformation ensemble consisting of interconverting substates severely impairs their performance and applications in biomedicine. Therefore, developing new chemistries stabilizing aptamer conformation and exploring the conformation-performance relationship are highly desired. Herein, we developed an 8-methoxypsoralen-based photochemically covalent lock to stabilize aptamer conformation via crosslinking the inter-stranded thymine nucleotides at TpA sites. Systematical studies and molecular dynamics simulations were performed to explore the conformation-performance relationship of aptamers, revealing that conformation-stabilized aptamers displayed better ability to bind targets, adapt to physiological environment, resist macrophage uptake, prolong circulation half-life, accumulate in and penetrate into tumor than their counterparts. As expected, conformation-stabilized aptamers efficiently improved the therapeutic efficacy of aptamer-drug conjugation on tumor-bearing mice. Collectively, our study has developed a general, simple and economic strategy to stabilize aptamer conformation and shed light on the conformation-performance relationship of aptamers, laying a basis for promoting their basic researches and applications in biomedicine.

Experience with 2 years' intervention to progressively reduce salt supply to kitchens in elderly care facilities-challenges and further research: post hoc analysis of the DECIDE-Salt randomized clinical trial.

BACKGROUND: Progressive reduction of sodium intake is an attractive approach for addressing excessive salt intake, but evidence for this strategy in real practice is limited. We aimed to determine the feasibility, effectiveness, and safety of a progressive sodium intake reduction intervention in real-world setting. METHODS: We randomized 48 residential elderly care facilities in China, with 1612 participants aged 55 years and older, to either progressive reduction (PR, 24 facilities) or no reduction (NR, 24 facilities) of the supply of study salt to the kitchens of these facilities for 2 years. The primary efficacy outcome was systolic blood pressure (SBP) at any scheduled follow-up visit. Secondary efficacy outcomes included diastolic blood pressure (DBP) at any scheduled follow-up visit, and major adverse cardiovascular events (comprising non-fatal stroke, non-fatal myocardial infarction, hospitalized non-fatal heart failure, or vascular death) and total mortality. The perception of food saltiness, the addition of out-of-study salt in meals, and 24-h urinary sodium excretion were used as process indicators. RESULTS: Pre-specified analysis per randomization found no effect of the intervention on the 2-year overall mean systolic and diastolic blood pressure (SBP, DBP) and any other outcomes. However, post hoc analysis showed that the intervention effect on blood pressure varied over multiple follow-up visits (p for interaction < 0.046) and presented favorable differences at the 24-month visit (SBP = - 3.0 mmHg, 95%CI = - 5.6, - 0.5; p = 0.020; DBP = - 2.0 mmHg, 95%CI - 3.4, - 0.63; p = 0.004). The effect on 24-h sodium was non-significant (- 8.4 mmol, 95%CI = - 21.8 to 4.9, p = 0.216), though fewer participants with NR than with PR reported food tasting bland (odds ratio 0.46; 95%CI 0.29 to 0.73; p = 0.001). Reporting of bland food taste and other process measures indicated that intervention delivery and adherence were not fully achieved as designed. CONCLUSIONS: The experience of this real-world study demonstrated that achieving acceptability and sustainability of the progressive sodium intake reduction strategy among older adults was challenging, but it has shown potential for effectiveness in these and potentially other residential settings if the lessons of DECIDE-Salt are applied in further studies. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03290716).

Aromatic diglycosides from Sophora tonkinensis and a multi-step conformer filtering procedure for TDDFT calculation of flexible glycoside.

Three previously undescribed aromatic diglycosides (1, 5, and 8) and six known analogs (2-4, 6, 7, and 9) were isolated from the roots and rhizomes of Sophora tonkinensis Gagnep. Their structures were elucidated by detailed spectroscopic analysis. The absolute configuration of compound 8 was determined by comparing the experimental and TDDFT calculated ECD spectra of 8 and aglycone 8a. Furthermore, a multistep conformer filtering procedure for TDDFT calculation of flexible glycoside was proposed, which afforded high accuracy with acceptable computing cost in determining the absolute configuration of glycosides using quantum calculated ECD.

Aptamer Inhibits Tumor Growth by Leveraging Cellular Proteasomal Degradation System to Degrade c-Met in Mice.

Current action mechanisms for aptamer-based therapeutics depend on occupancy-driven pharmacology to mediate protein functions. We report a new mechanism where aptamers leverage cellular proteasomal degradation system to degrade proteins for cancer treatment. A DNA aptamer (hereinafter referred to as c-Met-Ap) binds to the extracellular domain of mesenchymal-epithelial transition factor (c-Met) and selectively induces c-Met phosphorylation at Y1003 and Y1349. The phosphorylation of Y1003 recruits E3 ubiquitin ligase casitas B-lineage lymphoma, causing c-Met ubiquitination and degradation in the proteasome. Furthermore, c-Met-Ap can induce a decrease in the heterodimeric partner proteins of c-Met and the downstream effector proteins in the c-Met signal axis, effectively inhibiting tumor growth in A549 tumor-bearing BALB/c mice. Our study uncovers a novel, actionable mechanism for aptamer therapeutics and opens a new avenue for developing highly efficient anticancer drugs.

Genetic Spectrum Identified by Exome Sequencing in a Chinese Pediatric Cerebral Palsy Cohort.

OBJECTIVE: To explore the genetic spectrum of cerebral palsy (CP) in a Chinese pediatric cohort. STUDY DESIGN: This was a retrospective observational study of patients with CP from the Children's Hospital of Fudan University between June 2015 and December 2019. Their clinical data and exome sequencing data were collected and analyzed. RESULTS: A total of 217 patients with CP were enrolled, and genetic variants were identified in 78 subjects (35.9%): 65 patients with single-nucleotide variants (SNVs), 12 patients with copy number variants, and 1 patient with both an SNV and a copy number variant. The genetic diagnosis rates were significantly greater in patients without clinical risk factors than in patients with clinical risk factors (χ2 = 21.705, P = .000) and were significantly greater in patients with a family history than in those without a family history (χ2 = 4.493, P = .034). Variants in genes related to neurologic disorders were the most commonly detected variants, affecting 41 patients (62.1%, 41/66). Among the patients with SNVs detected, the top 12 genes were found to cover 62.1% (41/66) of cases, and 39.4% (26/66) of patients with SNVs had medically actionable genetic findings. CONCLUSIONS: The overall genetic diagnostic rate in this study was 35.9%, and patients without any clinical risk factors or with a family history were more likely to have genetic risk factors. The top 12 genes detected in this study as well as genes related to neurologic disorders or other medically actionable disorders should be noted in the analysis of genetic testing results in patients with CP.

Effect of Annulation Mode of Twistarene on the Physical Property and Self-Assembly Behavior of Functionalized Curved Aromatic Molecules.

Four novel curved polycyclic aromatic hydrocarbons 3 a, 5, 8, 15 a have been synthesized and characterized, where molecules 3 a and 15 a bear [5]carbohelicene units. X-ray single crystal analyses indicate that compound 3 a shows offset packing arrangements of (P5 )- and (M5 )-isomers, and 15 a has a symmetrical plane and looks like a butterfly. In comparison, 8 exhibits a slightly curved structure, in which the significant convex-to-convex π-overlap with the shortest distance of 3.42 Šoccurs. In addition, the effect of annulation mode of twistarenes on the physical properties, self-assembly behaviors, and switchable photoconductivity of the as-prepared curved aromatic compounds were further examined in a comparative manner.

Structures and Biological Activities of Polyacylated ent-Kaurane Diterpenoid Glycosides from the Aerial Parts of Inula hupehensis.

Sixteen new (1-16) and three known (17-19) polyacylated ent-kaurane diterpenoid glycosides were isolated from the aerial parts of Inula hupehensis. The planar structures of 1-16 and their relative configurations were established on the basis of extensive spectroscopic analysis. The absolute configurations of all stereogenic centers for compounds 1 and 6 were determined by single-crystal X-ray diffraction experiments, and the absolute configurations of the other new compounds were assigned by chemical degradation and experimental ECD data. Antineuroinflammatory testing of all the isolates showed that compound 5 inhibited lipopolysaccharide-induced nitric oxide production in BV-2 microglial cells with an IC50 value of 15.6 µM. In an α-glucosidase inhibitory assay, compound 13 exhibited a strong inhibitory effect with an IC50 value of 32.8 µM, whereas the IC50 value of the positive control, acarbose, was 387.8 µM.

From metabolomic analysis to quality assessment and biosynthetic insight in traditional Chinese medicine: Mulberry tree as a case study.

INTRODUCTION: Ramulus Mori (RM, Sangzhi) and Cortex Mori (CM, Sangbaipi) both come from the Chinese medicinal plant mulberry tree. CM is usually used to relieve cough, while RM is usually used to treat pain. There are no studies on the quality control of RM and CM based on their analgesic and anti-inflammatory constituents associated with their traditional use. The chemical profiles of CM and RM were confusing. Some CM had similar profiles to RM, but some did not. OBJECTIVE: We aimed to reveal the chemical differences between RM and CM and to evaluate their quality. MATERIALS AND METHODS: Their chemical differences were studied using metabolomic analysis based on UHPLC-ESI-MS data. The contents of five quality marker candidates were determined by UHPLC-PDA. The analgesic activities of morusin and kuwanon C were assessed by an acetic acid-induced writhing test. RESULTS: CM was characterized by chemical diversity, whereas RM had good homogeneity. Four groups of CM were classified based on their chemicals. The chemical profiles of CM group 4 were more similar to that of RM. Eighteen putative features were identified based on an MS-Finder search and fragmentation rules. Content limits for four quality markers with anti-inflammatory or analgesic activities were proposed for RM. Furthermore, a possible biosynthetic relationship between kuwanon C, kuwanon G, and morusin was hypothesized based on the high Pearson coefficient between kuwanon G and morusin. CONCLUSION: The obtained results may be useful in the evaluation of RM and CM and afford insight into the biosynthetic pathway of Diels-Alder adducts in Morus.

Antimicrobial alkaloids from the root bark of Dictamnus dasycarpus.

Two new furoquinoline alkaloids, named 1'-oxo-isoplatydesmine (1) and demethoxyacrophylline (2), as well as 11 known alkaloids (3-13) were isolated from the root bark of Dictamnus dasycarpus Turcz. The structures of 1 and 2 were established by detailed spectroscopic elucidation, such as 1 D & 2 D NMR and HRMS, etc. The unexpected autoracemization of 1 was discussed based on the stereochemistry of reported dihydrofuroquinolines. Compounds 3-5 exhibited moderate inhibitory activities against Bacillus subtilis, Candida albicans, and Pseudomonas aeruginosa with MICs 32-64 µg/ml, revealing the active principles of D. dasycarpus for treating skin diseases in its traditional usage.

Fraxinellone Induces Hepatotoxicity in Zebrafish through Oxidative Stress and the Transporters Pathway.

Fraxinellone (FRA), a major active component from Cortex Dictamni, produces hepatotoxicity via the metabolization of furan rings by CYP450. However, the mechanism underlying the hepatotoxicity of FRA remains unclear. Therefore, zebrafish larvae at 72 h post fertilization were used to evaluate the metabolic hepatotoxicity of FRA and to explore the underlying molecular mechanisms. The results showed that FRA (10-30 µM) induced liver injury and obvious alterations in the metabolomics of zebrafish larvae. FRA induces apoptosis by increasing the level of ROS and activating the JNK/P53 pathway. In addition, FRA can induce cholestasis by down-regulating bile acid transporters P-gp, Bsep, and Ntcp. The addition of the CYP3A inhibitor ketoconazole (1 µM) significantly reduced the hepatotoxicity of FRA (30 µM), which indicated that FRA induced hepatotoxicity through CYP3A metabolism. Targeted metabolomics analysis indicates the changes in amino acid levels can be combined with molecular biology to clarify the mechanism of hepatotoxicity induced by FRA, and amino acid metabolism monitoring may provide a new method for the prevention and treatment of DILI from FRA.

Clinical exome sequencing as the first-tier test for diagnosing developmental disorders covering both CNV and SNV: a Chinese cohort.

BACKGROUND: Developmental disorders (DDs) are early onset disorders affecting 5%-10% of children worldwide. Chromosomal microarray analysis detecting CNVs is currently recommended as the first-tier test for DD diagnosis. However, this analysis omits a high percentage of disease-causing single nucleotide variations (SNVs) that warrant further sequencing. Currently, next-generation sequencing can be used in clinical scenarios detecting CNVs, and the use of exome sequencing in the DD cohort ahead of the microarray test has not been evaluated. METHODS: Clinical exome sequencing (CES) was performed on 1090 unrelated Chinese DD patients who were classified into five phenotype subgroups. CNVs and SNVs were both detected and analysed based on sequencing data. RESULTS: An overall diagnostic rate of 41.38% was achieved with the combinational analysis of CNV and SNV. Over 12.02% of patients were diagnosed based on CNV, which was comparable with the published CMA diagnostic rate, while 0.74% were traditionally elusive cases who had dual diagnosis or apparently homozygous mutations that were clarified. The diagnostic rates among subgroups ranged from 21.82% to 50.32%. The top three recurrent cytobands with diagnostic CNVs were 15q11.2-q13.1, 22q11.21 and 7q11.23. The top three genes with diagnostic SNVs were: MECP2, SCN1A and SCN2A. Both the diagnostic rate and spectrums of CNVs and SNVs showed differences among the phenotype subgroups. CONCLUSION: With a higher diagnostic rate, more comprehensive observation of variations and lower cost compared with conventional strategies, simultaneous analysis of CNVs and SNVs based on CES showed potential as a new first-tier choice to diagnose DD.

Novel PAK3 gene missense variant associated with two Chinese siblings with intellectual disability: a case report.

BACKGROUND: Intellectual disability (ID) constitutes the most common group of neurodevelopmental disorders. Exome sequencing has enabled the discovery of genetic mutations responsible for a wide range of ID disorders. CASE PRESENTATION: In this study, we reported on two male siblings, aged 4 and 2 years, with motor and mental developmental delays and mild dysmorphic facial features. To identify the genetic causes of these symptoms, we employed trio-whole exome sequencing for the proband. We found a novel hemizygous missense variant in the PAK3 gene (c.1112G > A, p.Cys371Tyr), which encodes the p21-activated kinase 3, in the proband, which inherited from mother. The younger brother also has the hemizygous variant, which was confirmed by Sanger sequencing. The variant is located in the kinase domain and was regarded as a likely pathogenic variant in this family. CONCLUSION: We diagnosed two male siblings with developmental delays as having a PAK3 likely pathogenic variant. This finding expands the list of PAK3 gene mutations associated with neurodevelopmental disorders and provides further details on its clinical features.

Development of self-tuned diamond milling system for fabricating infrared micro-optics arrays with enhanced surface uniformity and machining efficiency.

Infrared micro-optics arrays (MOAs) featuring large numbers of micro-freeform lenslet are required increasingly in advanced infrared optical systems. Ultra-precision diamond cutting technologies have been widely used to fabricate MOAs with high form accuracy. However, the existing technologies can easily cause the non-uniformly fractured surface of infrared MOAs, due to the inherent low fracture toughness and high anisotropy of infrared materials as well as the time-varying chip thickness induced by ever-changing height and slope of the desired MOAs. In this study, a novel self-tuned diamond milling (STDM) system is proposed to achieve the ductile cutting of infrared MOAs with enhanced the surface uniformity and machining efficiency, and the corresponding toolpath planning algorithm is developed. In STDM system, a dual-axial fast servo motion platform is integrated into a raster milling system to self-adaptively match the maximum chip thickness for each tool rotational cycle with the critical depth of cut of the infrared material according to the local surface topography, thereby obtaining crack-free lenslet with high surface uniformity. Practically, micro-aspheric MOAs free from fractures are successfully machined on single-crystal silicon, a typical infrared material, to validate the proposed cutting concept. Compared with the conventional diamond milling, the proposed STDM is demonstrated to be able to avoid the non-uniform fractures without needing to reduce feed rate, and a smaller surface roughness of 4 nm and nearly double machining efficiency are achieved.

CAT1 silencing inhibits TGF-ß1-induced mouse hepatic stellate cell activation in vitro and hepatic fibrosis in vivo.

Hepatic fibrosis is characterized by abnormal accumulation of extracellular matrix (ECM). Hepatic stellate cells (HSCs) are the primary cells that produce ECM in response to hepatic injury, and transforming growth factor-beta (TGF-ß) has been regarded as the central stimulus responsible for HSC-mediated ECM production. In the present study, we attempted to identify a critical factor in HSC activation and the underlying mechanism. By analyzing online microarray expression profiles, we found that the expression of high-affinity cationic amino acid transporter 1 (CAT1) was upregulated in hepatic fibrosis models and activated HSCs. We isolated and identified mouse HSCs (MHSCs) and found that in these cells, CAT1 was most highly upregulated by TGF-ß1 stimulation in both time- and dose-dependent manners. In vitro, CAT1 overexpression further enhanced, while CAT1 silencing inhibited, the effect of TGF-ß1 in promoting MHSC activation. In vivo, CAT1 silencing significantly improved the hepatic fibrosis induced by both CCl4 and non-alcoholic fatty liver disease (NAFLD). In summary, CAT1 was significantly upregulated in TGF-ß1-activated MHSCs and mice with hepatic fibrosis. CAT1 silencing inhibited TGF-ß1-induced MHSC activation in vitro and fibrogenic changes in vivo. CAT1 is a promising target for hepatic fibrosis treatment that requites further investigation in human cells and clinical practice.

Sesquineolignan and neolignan enantiomers from Triadica sebifera.

Two pairs of new sesquineolignan enantiomers (1a/1b and 1c/1d), two pair of new 4',7-epoxy-8,3'-neolignan enantiomers (2a/2b and 3a/3b), and a pair of new 3',7-epoxy-8,4'-oxyneolignan enantiomers (4a/4b), along with two pairs of known 4',7-epoxy-8,3'-neolignan enantiomers (5a/5b and 6a/6b), were obtained from the stems and leaves of Triadica sebifera. The structures of the enantiomers were elucidated by spectroscopic analyses, and their absolute configurations were assigned by the experimental ECD spectra. Among them, compounds 5b, 6a and 6b showed inhibitory activities against NO production in activated microglial BV-2 cells, with IC50 values of 14.3, 23.2 and 33.3 µM, respectively.

Single probe shear scanning method for on-machine measurement of an optical profile.

This study presents a new (to the best of our knowledge) error separation method with a single displacement probe, named as single probe shear scanning (SPSS) method, for the on-machine optical profile measurement to overcome the problems of the existing multiprobe method like the large deviation of probe spacing and the probes' performance difference. The confocal sensor with superior dynamic range, high lateral resolution, and large measurement angle to surface is applied in this study to fulfill the measurement of the optical aspheric surface. The single probe measurement system, in which the probe fixed on a flexure hinge is driven straight within a millimeter-level travel range, is established to realize the function of the multiprobe. For the established system, a new exact profile reconstruction algorithm is built to eliminate the influences of straightness errors of the scanning stage and the systemic errors of shear stage, and to reduce the effect of the sensor drift. The reconstruction algorithms by difference measurement with two shears are studied to build the bidirectional segment stitching reconstruction method, which reduces the error accumulation and improves the reconstruction accuracy under the condition of measuring errors. A profile reconstruction method with three shears measurement is proposed to make a further improvement on the reconstruction accuracy. The proposed reconstruction method with three shears measurement is successfully employed for the on-machine measurement of an aspheric surface profile, and the evaluation results agree well with those from the Taylor profiler.

Limitation on activities of daily living, depressive symptoms and suicidal ideation among nursing home residents: The moderating role of resilience.

Nursing home residents are at a higher risk of suicidal ideation, and depressive symptoms and limitations on activities of daily living (ADL) are presumed to be contributory factors, whereas resilience may buffer the negative effects of risk factors. This study aimed to investigate the prevalence of suicidal ideation and the moderating effect of resilience on suicidal ideation to dilute the adverse contribution of ADL limitation and depressive symptoms. A stratified random sampling was used to recruit 538 residents from 37 nursing homes in China. Participants' suicidal ideation, resilience, depressive symptoms, and ADL limitation were measured and tested by structural equation modeling. Statistics show that 14.9% of participants had suicidal ideation and the model where resilience moderated the effects of ADL limitation and depressive symptoms on suicidal ideation had the best model fit index. This suggests that positive psychological interventions for resilience building might be effective in reducing suicidal ideation.

Metabolomic analysis of raw Pinelliae Rhizoma and its alum-processed products via UPLC-MS and their cytotoxicity.

Alum-processing is a traditional method to attenuate the toxicity of Pinelliae Rhizoma (tubers of Pinellia ternate, PT). The present study aimed at investigating the chemical and cytotoxic changes during alum processing. Metabolomic profiles of raw and alum-processed PT were studied based on ultra-performance liquid chromatography coupled with Orbitrap mass spectrometry. More than 80 chemicals in positive MS mode and 40 chemicals in negative MS mode, such as organic acids, amino acids, glucosides and nucleosides, were identified after multivariate statistical analysis, including principal component analysis and orthogonal partial least-square discriminant analysis. Almost all of the identified chemical markers were significantly decreased ~10- to 100-fold after alum processing. Meanwhile, the correlations between the chemical markers were assimilated to a positive coefficient from disorderly distribution during the processing. Raw PT extracts could inhibit the proliferation of human carcinoma cells (HCT-116, HepG2, and A549) at the rate of 40.5, 24.8 and 31.6% more strongly than processed PT. It was concluded that the alum processing of PT could decrease the number of actively water-soluble principles at the same time as decreasing toxicity. Given the water-insoluble property of toxic calcium oxalate raphides in PT, we suggest that a more scientific processing method should be sought.

Bioactive phenolic acid-substituted glycoses and glycosides from rhizomes of Cibotium barometz.

Two rarely phenolic acid-substituted alloses (1, 2) and one new glucoside (3), as well as nine known compounds (4-12) were isolated from rhizomes of Cibotium barometz (L.) J. Sm. Structures of 1-3 were established by extensively spectroscopic analyses (NMR, MS, etc.) and acid hydrolysis. All compounds were evaluated for the hepatoprotective activities against APAP-induced HepG2 cell damage. Compounds 1, 4-7, 10 exhibited significant hepatoprotective activities, even more strongly than positive control, bicycol. In addition, compounds 1 and 9 could reduce PC12 cell death induced by serum deprivation.