C-terminal glutamine acts as a C-degron targeted by E3 ubiquitin ligase TRIM7.

The exposed N-terminal or C-terminal residues of proteins can act, in cognate sequence contexts, as degradation signals (degrons) that are targeted by specific E3 ubiquitin ligases for proteasome-dependent degradation by N-degron or C-degron pathways. Here, we discovered a distinct C-degron pathway, termed the Gln/C-degron pathway, in which the B30.2 domain of E3 ubiquitin ligase TRIM7 (TRIM7B30.2) mediates the recognition of proteins bearing a C-terminal glutamine. By determining crystal structures of TRIM7B30.2 in complexes with various peptides, we show that TRIM7B30.2 forms a positively charged binding pocket to engage the "U"-shaped Gln/C-degron. The four C-terminal residues of a substrate play an important role in C-degron recognition, with C-terminal glutamine as the principal determinant. In vitro biochemical and cellular experiments were used to further analyze the substrate specificity and selective degradation of the Gln/C-degron by TRIM7.

Direct Quantitative Analysis of Fluorine in Solid Samples by Cryogenic Laser Ablation and Ionization Time-of-Flight Mass Spectrometry.

The determination of fluorine, the lightest element in halogens, suffers from high ionization potential and spectral interference from water molecules in mass spectrometry. Herein, we introduced a liquid nitrogen cooling unit into the laser ablation and ionization source for the first time to construct a cryogenic laser ablation and ionization time-of-flight mass spectrometry (Cryo-LAI-TOFMS) system. With this system, the interference of water-related species at m/z 19 was effectively eliminated, and fluorine atomization and ionization efficiency could reach 6.3%. A direct quantitative analysis method was developed to determine fluorine contents in phosphate rock, copper ore, industrial byproduct gypsum, stream sediment, and soil. Considering the simplicity, high sensitivity, and low spectral interference of this technique, it can be extended to the determination of fluorine content as low as µg/g in complex solid samples.

Glutathione-responsive PROTAC for targeted degradation of ERα in breast cancer cells.

ERα (estrogen receptor-α)-targeting PROTACs (PROteolysis TArgeting Chimeras) have emerged as a novel and promising modality for breast cancer therapeutics. However, ERα PROTACs-induced degradation in normal tissues raises concerns about potential off-tissue toxicity. Tumor microenvironment-responsive strategy provides potential for specific control of the PROTAC's on-target degradation activity. The glutathione (GSH) level has been reported to be significantly increased in tumor cells. Here, we designed a GSH-responsive ERα PROTAC, which is generated by conjugating an o-nitrobenzenesulfonyl group to the hydroxyl group of VHL-based ERα PROTAC through a nucleophilic substitution reaction. The o-nitrobenzenesulfonyl group as a protecting group blocks the bioactivity of ERα PROTAC (ER-P1), and that can be specifically recognized and removed by highly abundant GSH in cancer cells. Consequently, the GSH-responsive ERα PROTAC (GSH-ER-P1) exhibits significantly enhanced degradation of ERα in cancer cells compared to that in normal cells, leading to a remarkable inhibition of breast cancer cell proliferation and less toxic effects on normal cells. This study provides a potentially valuable strategy for breast cancer treatment using tumor microenvironment-responsive PROTACs.

A Communication-Efficient, Privacy-Preserving Federated Learning Algorithm Based on Two-Stage Gradient Pruning and Differentiated Differential Privacy.

There are several unsolved problems in federated learning, such as the security concerns and communication costs associated with it. Differential privacy (DP) offers effective privacy protection by introducing noise to parameters based on rigorous privacy definitions. However, excessive noise addition can potentially compromise the accuracy of the model. Another challenge in federated learning is the issue of high communication costs. Training large-scale federated models can be slow and expensive in terms of communication resources. To address this, various model pruning algorithms have been proposed. To address these challenges, this paper introduces a communication-efficient, privacy-preserving FL algorithm based on two-stage gradient pruning and differentiated differential privacy, named IsmDP-FL. The algorithm leverages a two-stage approach, incorporating gradient pruning and differentiated differential privacy. In the first stage, the trained model is subject to gradient pruning, followed by the addition of differential privacy to the important parameters selected after pruning. Non-important parameters are pruned by a certain ratio, and differentiated differential privacy is applied to the remaining parameters in each network layer. In the second stage, gradient pruning is performed during the upload to the server for aggregation, and the final result is returned to the client to complete the federated learning process. Extensive experiments demonstrate that the proposed method ensures a high communication efficiency, maintains the model privacy, and reduces the unnecessary use of the privacy budget.

Combined enhancement of the propionyl-CoA metabolic pathway for efficient androstenedione production in Mycolicibacterium neoaurum.

BACKGROUND: The production of androstenedione (AD) from phytosterols by Mycolicibacterium neoaurum is a multi-step biotransformation process, which requires degradation of sterol side chains, accompanied by the production of propionyl-CoA. However, the transient production of large amounts of propionyl-CoA can accumulate intracellularly to produce toxic effects and severely inhibit AD production. RESULTS: In the present study, the intracellular propionyl-CoA concentration was effectively reduced and the productivity of the strain was improved by enhancing the cytosolic methyl-branched lipid synthesis pathway and increasing the expression level of nat operator gene, respectively. Subsequently, the application of a pathway combination strategy, combined and the inducible regulation strategy, further improved AD productivity with a maximum AD conversion rate of 96.88%, an increase of 13.93% over the original strain. CONCLUSIONS: Overall, we provide a new strategy for reducing propionyl-CoA stress during biotransformation for the production of AD and other steroidal drugs using phytosterols.

Aberrant Kank1 expression regulates YAP to promote apoptosis and inhibit proliferation in OSCC.

The kidney ankyrin repeat-containing protein 1 (Kank1) gene is one of the most important members of the KANK family. Kank1 has hybridity deletion and promoter methylation in the cancer tissues of the brain, lung, kidney and the corresponding cell lines, leading to downregulation of the gene expression. Meanwhile, Kank1 also plays a key role in the occurrence and development of various types of tumors, suggesting that Kank1 may be an anti-oncogene. However, its role and the potential mechanisms in the Oral Squamous Cell Carcinoma (OSCC) remain unclear. We examined the expression of Kank1 in OSCC tissues and explored its clinical significance. In addition, we investigated the effects of Kank1 on the biological behavior of OSCC cells and their specific molecular mechanisms. We found that Kank1 was poorly expressed in OSCC tissues and it is correlated with the OSCC stage and the patient's poor prognosis. By overexpression of Kank1, we found that the proliferation ability of the OSCC cells decreased both in vitro and in vivo, the proportion of apoptotic cells increased, and the mitochondrial transmembrane potential decreased. In terms of the molecular mechanism, we confirmed that Kank1 could inhibit the occurrence of OSCC by regulating Yap to inhibit the proliferation and promote apoptosis of the OSCC cells. Moreover, it was found that the overexpression of YAP reversed those effects caused by Kank1 overexpression on the OSCC cells. In conclusion, the research indicated that Kank1 might play an anti-oncogenic role in OSCC and it could be considered to be a target for the diagnosis and the treatment of OSCC.

3D Nanoscale Chemical Imaging of Core-Shell Microspheres via Microlensed Fiber Laser Desorption Postionization Mass Spectrometry.

A laser desorption postionization (LDPI) nanoscale resolution mass spectrometry imaging (MSI) technique based on a microlensed fiber is proposed for 3D imaging of microspheres which have a core-shell structure. Results show that the diameter of the sampling crater can be as small as 350 nm by introducing the desorption laser to the sample surface through the microlensed fiber. The use of laser postionization greatly solves the problem of weak signal caused by the very small sampling amount. A line scan of a sharp edge of Cr mesh shows that the imaging resolution of this method can reach to 300 nm. Through the imaging analysis of the alloy core-shell microspheres of Cr, Fe, Co, and Cu, the distribution of four elements at different positions can be observed visually. Particularly, the reconstruction 3D image of a single Nb-Zr core-shell particle demonstrates the potential of this technique in 3D imaging.

Vagus nerve stimulation reverses ventricular electrophysiological changes induced by hypersympathetic nerve activity.

NEW FINDINGS: What is the central question of this study? Previous studies have shown that hypersympathetic nerve activity results in ventricular electrophysiological changes and facilitates the occurrence of ventricular arrhythmias. Vagus nerve stimulation has shown therapeutic potential for myocardial infarction-induced ventricular arrhythmias. However, the actions of vagus nerve stimulation on hypersympathetic nerve activity-induced ventricular electrophysiological changes are still unknown. What is the main finding and its importance? We show that vagus nerve stimulation is able to reverse hypersympathetic nerve activity-induced ventricular electrophysiological changes and suppress the occurrence of ventricular fibrillation. These findings further suggest that vagus nerve stimulation may be an effective treatment option for ventricular arrhythmias, especially in patients with myocardial infarction or heart failure. Vagus nerve stimulation (VNS) has shown therapeutic potential for myocardial infarction-induced ventricular arrhythmias. This study aimed to investigate the effects of VNS on ventricular electrophysiological changes induced by hypersympathetic nerve activity. Seventeen open-chest dogs were subjected to left stellate ganglion stimulation (LSGS) for 4 h to simulate hypersympathetic tone. All animals were randomly assigned to the VNS group (n = 9) or the control group (n = 8). In the VNS group, VNS was performed at the voltage causing a 10% decrease in heart rate for hours 3-4 during 4 h of LSGS. During the first 2 h of LSGS, the ventricular effective refractory period (ERP) and action potential duration (APD) were both progressively and significantly decreased; the spatial dispersion of ERP, maximal slope of the restitution curve and pacing cycle length of APD alternans were all increased. With LSGS + VNS during the next 2 h, there was a significant return of all the altered electrophysiological parameters towards baseline levels. In the eight control dogs that received 4 h of LSGS without VNS, all the parameters changed progressively, but without any reversals. The ventricular fibrillation threshold was higher in the VNS group than in the control group (17.3 ± 3.4 versus 11.3 ± 3.8 V, P < 0.05). The present study demonstrated that VNS was able to reverse LSGS-induced ventricular electrophysiological changes and suppress the occurrence of ventricular fibrillation.

Comparison on biological nutrient removal and microbial community between full-scale anaerobic/anoxic/aerobic process and its upgrading processes.

A comparative study was conducted for the anaerobic/anoxic/aerobic (AAO) process and its two upgrading processes, five-stage Bardenpho and AAO coupling moving bed bioreactors (AAO + MBBR), using long-term operation data of six full-scale wastewater treatment plants. The three processes all had good COD and phosphorus removal performance. The reinforcing effects of carriers on nitrification were moderate at full-scale applications, while the Bardenpho was advantageous in nitrogen removal. The AAO + MBBR and Bardenpho processes both had higher microbial richness and diversity than the AAO. The AAO + MBBR favored bacteria to degrade complex organics (Ottowia and Mycobacterium) and to form biofilms (Novosphingobium), and preferentially enriched denitrifying phosphorus-accumulating bacteria (DPB) (norank_o__Run-SP154) with the highest anoxic to aerobic phosphorus uptake rates of 65.3 % - 83.9 %. The Bardenpho enriched bacteria tolerant to varied environments (Norank_f__Blastocatellaceae, norank_o__Saccharimonadales, and norank_o__SBR103), and was more suitable for the upgrading of the AAO because of its excellent pollutant removal performance and flexible operation mode.

Under-loaded operation of an anaerobic-anoxic-aerobic system in dry and wet weather dynamics to prevent overflow pollution: Impacts on process performance and microbial community.

Effects of low hydraulic loading rate (HLR) in dry weather and high HLR in wet weather on pollutant removal, microbial community, and sludge properties of a full-scale wastewater treatment plant (WWTP) were extensively studied to explore the risk of under-loaded operation for overflow pollution control. Long-term low HLR operation had an insignificant effect on the pollutant removal performance of the full-scale WWTP, and the system could withstand high-load shocks in wet weather. Low HLR resulted in higher oxygen and nitrate uptake rate due to the storage mechanism under the alternating feast/famine condition, and lower nitrifying rate. Low HLR operation enlarged particle size, deteriorated floc aggregation and sludge settleability, and reduced sludge viscosity due to the overgrowth of filamentous bacteria and inhibition of floc-forming bacteria. The remarkable increase in Thuricola and the contract morphology of Vorticella in microfauna observation confirmed the risk of flocs disintegration in low HLR operation.

In Situ Generated Novel 1H MRI Reporter for ß-Galactosidase Activity Detection and Visualization in Living Tumor Cells.

For wide applications of the lacZ gene in cellular/molecular biology, small animal investigations, and clinical assessments, the improvement of noninvasive imaging approaches to precisely assay gene expression has garnered much attention. In this study, we investigate a novel molecular platform in which alizarin 2-O-ß-d-galactopyranoside AZ-1 acts as a lacZ gene/ß-gal responsive 1H-MRI probe to induce significant 1H-MRI contrast changes in relaxation times T 1 and T 2 in situ as a concerted effect for the discovery of ß-gal activity with the exposure of Fe3+. We also demonstrate the capability of this strategy for detecting ß-gal activity with lacZ-transfected human MCF7 breast and PC3 prostate cancer cells by reaction-enhanced 1H-MRI T 1 and T 2 relaxation mapping.

Economical production of androstenedione and 9α-hydroxyandrostenedione using untreated cane molasses by recombinant mycobacteria.

Production of androstenedione (AD) and 9α-hydroxyandrostenedione (9α-OH-AD) by recombinant mycobacteria using untreated cane molasses and hydrolysate of mycobacterial cells (HMC) was investigated for the first time. B-vitamins feeding experiment and reverse transcription-PCR analysis showed that propionyl-CoA carboxylase (PCC) plays an important role in the phytosterol biotransformation of mycobacteria. The respective AD and 9α-OH-AD conversion ratios were increased by 2.91 and 1.48 times through coexpression of PCC and NADH dehydrogenase. The highest conversion ratios of AD and 9α-OH-AD obtained by using a co-feeding strategy of cane molasses and HMC reached 96.38% and 95.04%, respectively, and the total costs of carbon and nitrogen sources for the culture medium were reduced by 29.89% and 49.49%, respectively. Taking the results together, untreated cane molasses and HMC can be used for the economical production of steroidal pharmaceutical precursors by mycobacteria. This study offers an economical and green strategy for steroidal pharmaceutical precursor production.

Comparative study of thyroid hormone and antithyroid antibody levels in patients with gestational diabetes mellitus and pregnant patients with diabetes.

BACKGROUND: The aim of this study was to investigate the levels of thyroid hormone and antithyroid antibodies and their relationship with pregnancy outcome in patients with gestational diabetes mellitus (GDM) and diabetic patients. METHODS: Fifty patients with GDM and 50 pregnant patients with diabetes were selected. Their levels of fasting blood glucose (FBG), glycosylated hemoglobin, FT3, FT4, TGab, TSH, TPOab were measured until parturition. RESULTS: There were no statistically significant differences in the age, gestational age, weight, FBG and glycosylated hemoglobin between the two groups (P>0.05). The levels of FT3 and FT4 in patients with GDM were significantly lower than those in diabetic pregnant patients, while the levels of TSH, TGab, TPOab of GDM patients were significantly higher than in diabetic pregnant patients (P<0.05). The total incidence rates of premature delivery, post-term birth and cesarean section in patients with GDM were significantly higher than those in diabetic pregnant patients. At six-month follow-up, the intellectual levels of infants delivered by patients with GDM were significantly lower than those of diabetic pregnant patients (P<0.05). CONCLUSIONS: The levels of thyroid hormones and related antibodies in patients with GDM were abnormal, which may have affected outcome of pregnancy and the intellectual level of their infants.

Common and rare exonic MUC5B variants associated with type 2 diabetes in Han Chinese.

Genome-wide association studies have identified over one hundred common genetic risk variants associated with type 2 diabetes (T2D). However, most of the heritability of T2D has not been accounted for. In this study, we investigated the contribution of rare and common variants to T2D susceptibility by analyzing exome array data in 1,908 Han Chinese genotyped with Affymetrix Axiom® Exome Genotyping Arrays. Based on the joint common and rare variants analysis of 57,704 autosomal SNPs within 12,244 genes using Sequence Kernel Association Tests (SKAT), we identified significant associations between T2D and 25 variants (9 rare and 16 common) in MUC5B, p-value 1.01×10-14. This finding was replicated (p = 0.0463) in an independent sample that included 10,401 unrelated individuals. Sixty-six of 1,553 possible haplotypes based on 25 SNPs within MUC5B showed significant association with T2D (Bonferroni corrected p values < 3.2×10-5). The expression level of MUC5B is significantly higher in pancreatic tissues of persons with T2D compared to those without T2D (p-value = 5×10-5). Our findings suggest that dysregulated MUC5B expression may be involved in the pathogenesis of T2D. As a strong candidate gene for T2D, MUC5B may play an important role in the mechanisms underlying T2D etiology and its complications.

The Use of Calcium Channel Blockers in the Treatment of Coronary Spasm and Atrioventricular Block.

Calcium channel blockers have been used in the treatment of coronary artery spasm for many years. However, there is insufficient knowledge about their application to treat atrioventricular block caused by coronary spasm. Clinical data of five patients who were diagnosed with coronary spasm caused by atrioventricular block and treated with calcium channel blockers were retrospectively assessed. The patients had varying degrees of atrioventricular block (confirmed by Holter ECG) and myocardial ischemia-like ST-T changes. Two patients were II type I AVB, two patients II type II AVB, and the remaining one patient was III AVB. All patients were all diagnosed with right coronary artery spasm by coronary angiography. The patients were treated with calcium channel blockers. No patient reported recurrence of chest pain or chest discomfort. On Holter ECG monitoring, no significant myocardial ischemia or atrioventricular block was seen. In conclusion, calcium channel blockers are effective and safe in the treatment of atrioventricular block caused by coronary spasm.

Research on Acute Toxicity and Pharmacodynamics of Jinyulian Oral Solution.

A research on Jinyulian Oral Solution was conducted and the objectives were to discover its possible acute toxicity and antibacterial effects when used in vitro and in vivo. Regarding the acute toxicity test, Kunming mice were fed a maximum amount of the solution as their stomachs could hold, i.e., 40 mL kg(-1). To ascertain the minimum inhibitory concentration (MIC) of the solution, two types of germs, i.e., Staphylococcus aureus and Escherichia coli, were selected and tube dilution method was adopted. An antibacterial experimental model relying on animals' body was developed for the researchers to observe the solution's antibacterial effects. Test results showed that no abnormalities were discovered within 14 days after the initial date of testing and the mice grew as normal when fed with an amount of the solution 250 times of a normal clinical doze (In this case a man was assumed to weigh 60 kg.) and that the solution demonstrated obvious antibacterial effects on the two types of selected germs. The respective measured MIC50 and MIC90 values of the two germs were 3.2, 12.8, 6.4, and 25.6 mg L(-1). Therefore, it is reasonable to conclude that Jinyulian Oral Solution possesses no acute toxicity but obvious antibacterial effects on the two before-mentioned germs.

Tumor necrosis factor-alpha G-238A polymorphism and coronary artery disease risk: a meta-analysis of 4,222 patients and 4,832 controls.

BACKGROUND: The aim of the present study was to investigate the association between tumor necrosis factor-alpha (TNF-α) gene G-238A polymorphism and risk of coronary artery disease (CAD) using a meta-analytical approach. METHODS: The PubMed and Embase databases were searched for relevant publications up to January 13, 2015. Four authors (XPH, XDZ, XTZ, and ZJZ) independently selected the studies, extracted, and analyzed the data using the Comprehensive Meta-Analysis software. The sensitivity and subgroups analyses were also performed. Either a fixed effects or a random effects model was used to estimate pooled odds ratios (ORs) and their 95% confidence intervals (CIs). RESULTS: Finally, ten articles including eleven case-control studies involving 4,222 patients and 4,832 controls were yielded. The results indicated no significant association between G-238A polymorphism and CAD risk (A vs G: OR =1.08, 95% CI =0.89-1.30; AA vs GG: OR =1.15, 95% CI =0.59-2.25; GA vs GG: OR =1.14, 95% CI =0.88-1.48; AA vs [GG + GA]: OR =1.09, 95% CI =0.56-2.14; (GA + AA) vs GG: OR =1.11, 95% CI =0.90-1.38). In the subgroup analyses, similar results were obtained with overall populations. The sensitivity analyses showed that the overall results were robust. No publication bias was detected. CONCLUSION: Based on current evidence, we can conclude that TNF-α G-238A polymorphism might not be associated with CAD risk.

Variation in APOL1 Contributes to Ancestry-Level Differences in HDLc-Kidney Function Association.

Low levels of high-density cholesterol (HDLc) accompany chronic kidney disease, but the association between HDLc and the estimated glomerular filtration rate (eGFR) in the general population is unclear. We investigated the HDLc-eGFR association in nondiabetic Han Chinese (HC, n = 1100), West Africans (WA, n = 1497), and African Americans (AA, n = 1539). There were significant differences by ancestry: HDLc was positively associated with eGFR in HC (ß = 0.13, P < 0.0001), but negatively associated among African ancestry populations (WA: -0.19, P < 0.0001; AA: -0.09, P = 0.02). These differences were also seen in nationally-representative NHANES data (among European Americans: 0.09, P = 0.005; among African Americans -0.14, P = 0.03). To further explore the findings in African ancestry populations, we investigated the role of an African ancestry-specific nephropathy risk variant, rs73885319, in the gene encoding HDL-associated APOL1. Among AA, an inverse HDLc-eGFR association was observed only with the risk genotype (-0.38 versus 0.001; P = 0.03). This interaction was not seen in WA. In summary, counter to expectation, an inverse HDLc-eGFR association was observed among those of African ancestry. Given the APOL1 × HDLc interaction among AA, genetic factors may contribute to this paradoxical association. Notably, these findings suggest that the unexplained mechanism by which APOL1 affects kidney-disease risk may involve HDLc.