Directed evolution of Escherichia coli surface-displayed Vitreoscilla hemoglobin as an artificial metalloenzyme for the synthesis of 5-imino-1,2,4-thiadiazoles.

Artificial metalloenzymes (ArMs) are constructed by anchoring organometallic catalysts to an evolvable protein scaffold. They present the advantages of both components and exhibit considerable potential for the in vivo catalysis of new-to-nature reactions. Herein, Escherichia coli surface-displayed Vitreoscilla hemoglobin (VHbSD-Co) that anchored the cobalt porphyrin cofactor instead of the original heme cofactor was used as an artificial thiourea oxidase (ATOase) to synthesize 5-imino-1,2,4-thiadiazoles. After two rounds of directed evolution using combinatorial active-site saturation test/iterative saturation mutagenesis (CAST/ISM) strategy, the evolved six-site mutation VHbSD-Co (6SM-VHbSD-Co) exhibited significant improvement in catalytic activity, with a broad substrate scope (31 examples) and high yields with whole cells. This study shows the potential of using VHb ArMs in new-to-nature reactions and demonstrates the applicability of E. coli surface-displayed methods to enhance catalytic properties through the substitution of porphyrin cofactors in hemoproteins in vivo.

FOXA1 regulates ribosomal RNA transcription in prostate cancer.

BACKGROUND: Ribosome biogenesis is excessively activated in tumor cells, yet it is little known whether oncogenic transcription factors (TFs) are involved in the ribosomal RNA (rRNA) transactivation. METHODS: Nucleolar proteomics data and large-scale immunofluorescence were re-analyzed to jointly identify the proteins localized at nucleolus. RNA-Seq data of five prostate cancer (PCa) cohorts were combined and integrated with multi-dimensional data to define the upregulated nucleolar TFs in PCa tissues. Then, ChIP-Seq data of PCa cell lines and two PCa clinical cohorts were re-analyzed to reveal the TF binding patterns at ribosomal DNA (rDNA) repeats. The TF binding at rDNA was validated by ChIP-qPCR. The effect of the TF on rRNA transcription was determined by rDNA luciferase reporter, nascent RNA synthesis, and global protein translation assays. RESULTS: In this study, we reveal the role of oncogenic TF FOXA1 in regulating rRNA transcription within nucleolar organization regions. By analyzing human TFs in prostate cancer clinical datasets and nucleolar proteomics data, we identified that FOXA1 is partially localized in the nucleolus and correlated with global protein translation. Our extensive FOXA1 ChIP-Seq analysis provides robust evidence of FOXA1 binding across rDNA repeats in prostate cancer cell lines, primary tumors, and castration-resistant variants. Notably, FOXA1 occupancy at rDNA repeats correlates with histone modifications associated with active transcription, namely H3K27ac and H3K4me3. Reducing FOXA1 expression results in decreased transactivation at rDNA, subsequently diminishing global protein synthesis. CONCLUSIONS: Our results suggest FOXA1 regulates aberrant ribosome biogenesis downstream of oncogenic signaling in prostate cancer.

Bioassessment of Macroinvertebrate Communities Influenced by Gradients of Human Activities.

This study explores the impact of anthropogenic land use changes on the macroinvertebrate community structure in the streams of the Cangshan Mountains. Through field collections of macroinvertebrates, measurement of water environments, and delineation of riparian zone land use in eight streams, we analyzed the relationship between land use types, stream water environments, and macroinvertebrate diversities. The results demonstrate urban land use type and water temperature are the key environmental factors driving the differences in macroinvertebrate communities up-, mid-, and downstream. The disturbed streams had lower aquatic biodiversity than those in their natural state, showing a decrease in disturbance-sensitive aquatic insect taxa and a more similar community structure. In the natural woodland area, species distributions may be constrained by watershed segmentation and present more complex community characteristics.

Application of Vitreoscilla Hemoglobin as a Green and Efficient Biocatalyst for the Synthesis of Benzoxazoles in Water.

We report an efficient and eco-friendly method for the Vitreoscilla hemoglobin (VHb)-catalyzed synthesis of benzoxazoles in water at room temperature. tert-Butyl hydroperoxide and 2,2,6,6-tetramethyl-1-piperidinyloxy were used as oxidant and radical scavenger, respectively. A total of 27 functionally diverse benzoxazoles were prepared in moderate to high yields (62 %-94 %) by the annulation reaction of phenols with amines in the presence of VHb in 1 h. Thus, this method is highly viable for practical applications. This work broadens the application of hemoglobin to organic synthesis.

Effects of 3-month Qigong exercise on heart rate variability and respiration in anxious college students.

OBJECTIVE: This longitudinal study aimed to investigate the effects of Qigong on the anxiety state, heart rate variability (HRV), and breathing of anxious college students. METHODS: A total of 37 individuals (18-25 years old) were randomly allocated to the control (n = 19) and intervention (n = 18) groups. Qigong interventions were conducted five times weekly for 12 weeks, with each session lasting 60 min. Hamilton Anxiety Scale, Fatigue Scale 14, Pittsburgh Sleep Quality Index, and 36-item Short Form Survey, HRV, and respiration data were collected before and after the 3-month intervention. RESULTS: Individuals who participated in the three-month Qigong exercise intervention showed a significant reduction in anxiety, particularly mental anxiety (p < 0.05). Subjects in the intervention group presented a decrease in skin temperature (p < 0.05) and an increase in blood volume pulsation (p < 0.05). Meanwhile, HRV exhibited a significant increase in the standard deviation of interbeat interval before and after comparisons (p < 0.05) and between the two groups (p = 0.039) and a reduction in the normalized low-frequency power after the intervention. Moreover, the intervention group experienced increased abdominal breathing depth and abdominal breathing per minute (p < 0.05). CONCLUSION: These findings indicate that Qigong is an effective mind-body exercise strategy for relieving anxiety. HRV and breathing were improved accordingly among college students after the completion of the 3-month Qigong program.

Atrial myxoma embolization of the basilar artery presenting with a convulsive seizure: Case report.

BACKGROUND: Basilar artery occlusion (BAO) is a rare cause of convulsive seizure. Such patients who are treated for epilepsy will miss the optimal time for treatment. Atrial myxoma is a rare cause of stroke and should be surgically removed as soon as possible after diagnosis. CASE SUMMARY: We report a patient who presented with convulsions as the initial symptom and was diagnosed with BAO by computed tomographic angiography. After transthoracic echocardiogram, the cause of the disease was diagnosed as atrial myxoma. The patient recovered well after endovascular treatment and resection of the atrial myxoma. CONCLUSION: A small number of patients with BAO present with convulsive seizures. It is very important to make a timely diagnosis. Direct thrombaspiration may be the best choice for basilar artery cardioembolization, and thrombectomy for distal moderate vascular occlusion in posterior circulation is feasible. Atrial myxoma is a rare cause of cardioembolic stroke and should be resected as soon as possible to prevent further embolic complications.

Engineering of Dual-Function Vitreoscilla Hemoglobin: A One-Pot Strategy for the Synthesis of Unnatural α-Amino Acids.

Despite a well-developed and growing body of work on the directed evolution of hemoproteins, the potential of hemoproteins to catalyze non-natural reactions remains underexplored. This paper reports a new biocatalytic strategy for the one-pot synthesis of unnatural α-amino acids. Engineered variants of dual-function Vitreoscilla hemoglobin were found to efficiently catalyze N-H insertion and C-H sp3 alkylation, providing moderate to excellent yields (57%-95%) of unnatural α-amino acid derivatives and turnover numbers (1425-2375).

Targeting the gut microbiota to alleviate chemotherapy-induced toxicity in cancer.

Despite ongoing breakthroughs in novel anticancer therapies, chemotherapy remains a mainstream therapeutic modality in different types of cancer. Unfortunately, chemotherapy-related toxicity (CRT) often leads to dose limitation, and even results in treatment termination. Over the past few years, accumulating evidence has indicated that the gut microbiota is extensively engaged in various toxicities initiated by chemotherapeutic drugs, either directly or indirectly. The gut microbiota can now be targeted to reduce the toxicity of chemotherapy. In the current review, we summarized the clinical relationship between the gut microbiota and CRT, as well as the critical role of the gut microbiota in the occurrence and development of CRT. We then summarized the key mechanisms by which the gut microbiota modulates CRT. Furthermore, currently available strategies to mitigate CRT by targeting the gut microbiota were summarized and discussed. This review offers a novel perspective for the mitigation of diverse chemotherapy-associated toxic reactions in cancer patients and the future development of innovative drugs or functional supplements to alleviate CRT via targeting the gut microbiota.

MYC reshapes CTCF-mediated chromatin architecture in prostate cancer.

MYC is a well characterized oncogenic transcription factor in prostate cancer, and CTCF is the main architectural protein of three-dimensional genome organization. However, the functional link between the two master regulators has not been reported. In this study, we find that MYC rewires prostate cancer chromatin architecture by interacting with CTCF protein. Through combining the H3K27ac, AR and CTCF HiChIP profiles with CRISPR deletion of a CTCF site upstream of MYC gene, we show that MYC activation leads to profound changes of CTCF-mediated chromatin looping. Mechanistically, MYC colocalizes with CTCF at a subset of genomic sites, and enhances CTCF occupancy at these loci. Consequently, the CTCF-mediated chromatin looping is potentiated by MYC activation, resulting in the disruption of enhancer-promoter looping at neuroendocrine lineage plasticity genes. Collectively, our findings define the function of MYC as a CTCF co-factor in three-dimensional genome organization.

Differential Roles of CD36 in Regulating Muscle Insulin Response Depend on Palmitic Acid Load.

The possible role of fatty acid translocase (CD36) in the treatment of obesity has gained increasing research interest since researchers recognized its coordinated function in fatty acid uptake and oxidation. However, the effect of CD36 deficiency on intracellular insulin signaling is complex and its impact may depend on different nutritional stresses. Therefore, we investigated the various effects of CD36 deletion on insulin signaling in C2C12 myotubes with or without palmitic acid (PA) overload. In the present work, we reported the upregulated expression levels of CD36 in the skeletal muscle tissues of obese humans and mice as well as in C2C12 myotubes with PA stimulation. CD36 knockdown using RNA interference showed that insulin signaling was impaired in CD36-deficient C2C12 cells in the absence of PA loading, suggesting that CD36 is essential for the maintenance of insulin action, possibly resulting from increased mitochondrial dysfunction and endoplasmic reticulum (ER) stress; however, CD36 deletion improved insulin signaling in the presence of PA overload due to a reduction in lipid overaccumulation. In conclusion, we identified differential roles of CD36 in regulating muscle insulin response under conditions with and without PA overload, which provides supportive evidence for further research into therapeutic approaches to diabetes.

Efficacy and safety of early anticoagulation after endovascular treatment in patients with atrial fibrillation.

BACKGROUND: The timing for initiating anticoagulant therapy in acute ischaemic stroke (AIS) patients with atrial fibrillation who recanalised after endovascular treatment (EVT) is unclear. The objective of this study was to evaluate the effect of early anticoagulation after successful recanalisation in AIS patients with atrial fibrillation. METHODS: Patients with anterior circulation large vessel occlusion and atrial fibrillation who were successfully recanalised by EVT within 24 hours after stroke in the Registration Study for Critical Care of Acute Ischemic Stroke after Recanalization registry were analysed. Early anticoagulation was defined as the initiation of unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) within 72 hours after EVT. Ultra-early anticoagulation was defined if it was initiated within 24 hours. The primary efficacy outcome was the score on the modified Rankin Scale (mRS) at day 90, and the primary safety outcome was symptomatic intracranial haemorrhage within 90 days. RESULTS: Overall, 257 patients were enrolled, of whom 141 (54.9%) initiated anticoagulation within 72 hours after EVT, including 111 within 24 hours. A significant shift towards better mRS scores at day 90 was associated with early anticoagulation (adjusted common OR 2.08 (95% CI 1.27 to 3.41)). Symptomatic intracranial haemorrhage was comparable between patients treated with early and routine anticoagulation (adjusted OR 0.20 (95% CI 0.02 to 2.18)). Comparison of different early anticoagulation regimens showed that ultra-early anticoagulation was more significantly associated with favourable functional outcomes (adjusted common OR 2.03 (95% CI 1.20 to 3.44)) and reduced the incidence of asymptomatic intracranial haemorrhage (OR 0.37 (95% CI 0.14 to 0.94)). CONCLUSIONS: In AIS patients with atrial fibrillation, early anticoagulation with UFH or LMWH after successful recanalisation is associated with favourable functional outcomes without increasing the risk of symptomatic intracranial haemorrhages. TRIAL REGISTRATION NUMBER: ChiCTR1900022154.

Inactivation of microglia dampens blood-brain barrier permeability and loss of dopaminergic neurons in paraquat-lesioned mice.

Prior studies indicated the involvement of neuroinflammation in the dopaminergic neurodegeneration in mice of paraquat (PQ)-induced Parkinson's disease (PD), but the underlying mechanisms remain to be elucidated. The present study explored whether microglia-mediated inflammation disrupted blood-brain barrier (BBB) and its related mechanism. C57BL/6 mice were injected intraperitoneally with PQ, twice a week for six weeks, following with or without minocycline (intraperitoneal injection, once every two days). The microglial activation, BBB permeability, expression of tight junctions (TJs) proteins and matrix metalloproteinase (MMP), as well as the loss of dopaminergic neurons and neurological deficits assessment, were evaluated. Minocycline efficiently restrained nigral microglial activation induced by PQ in mice. PQ-induced increase of EB content in the brain and excessive expression of zonula occludin-1 (ZO-1), claudin-5 and occludin were significantly dampened by minocycline treatment. Inhibition of microglial activation by minocycline greatly ameliorated the loss of dopaminergic neurons and neurological dysfunctions in PQ-exposed mice. Also, microglial inactivation downregulated the expression of MMP-2/9 in PQ-lesioned mice. These findings suggested the potential protection of suppressing microglia-mediated neuroinflammation against dopaminergic neurodegeneration through attenuating BBB disruption in a mouse of PQ-induced PD, and MMP-2/9 might involve in the contribution, which needs to be verified in future study.

CD36 deficiency inhibits proliferation by cell cycle control in skeletal muscle cells.

Obesity-related muscular dysfunction and relative muscle atrophy affect an increasing number of people. Elucidating the molecular mechanisms of skeletal muscle cell development and growth may contribute to the maintenance of skeletal muscle mass in obesity. Fatty acid translocase (FAT/CD36), as a long-chain fatty acid transport protein, is crucial for lipid metabolism and signaling. CD36 is known to function in myogenic differentiation, and whether it affects the proliferation of skeletal muscle cells and the underlying mechanisms remain unclear. In this study, the effect of CD36 deficiency on skeletal muscle cell viability and proliferation was examined using C2C12 myoblasts. Results showed that the deletion of CD36 enhanced the inhibitory effect of PA on the proliferation and the promotion of apoptosis in skeletal muscle cells. Intriguingly, the silencing of CD36 suppressed cell proliferation by preventing the cell cycle from the G0/G1 phase to the S phase in a cyclin D1/CDK4-dependent manner. Overall, we demonstrated that CD36 was involved in skeletal muscle cell proliferation by cell cycle control, and these findings might facilitate the treatment of obesity-related muscle wasting.

Efficacy and safety of different modes of exercise-based cardiac rehabilitation delivery for patients with heart failure: a protocol for a systematic review and network meta-analysis.

INTRODUCTION: The prevalence of heart failure (HF) is increasing. Exercise-based cardiac rehabilitation (CR) reduces mortality and further improves the prognosis of patients with HF. However, the effect of different modes of CR delivery on HF remains unclear. Thus, the purpose of this study is to find out the relative efficacy and safety of different modes of CR delivery for individuals with HF using a network meta-analysis. METHODS AND ANALYSIS: We will perform a systematic review and network meta-analysis of randomised controlled trials which compare different modes of exercise-based CR delivery for patients with HF. Databases including Embase, Medline, the Cochrane Central Register of Controlled Trials and Web of Science will be searched up to May 2022. The primary outcomes will focus on the functional capacity and the health-related quality of life (hr-QOL). Functional capacity will be evaluated by peak oxygen consumption (mL/kg/min) and 6 min walking test (metres). The Minnesota Living with Heart Failure questionnaire, Short Form-36, Psychometric properties of the Kansas City cardiomyopathy questionnaire and EuroQol five dimensions questionnaire will serve as measures of hr-QOL. As secondary outcomes, we will assess hospital admissions (all-cause and cardiac) and all-cause mortality, which required a minimum follow-up of 6 months, as well as adverse events during exercise training. The risk of bias for individual studies will be evaluated according to the Cochrane Handbook. The quality of evidence will be assessed by the Grading of Recommendations, Assessment, Development and Evaluation approach. ETHICS AND DISSEMINATION: This study does not require ethics approval as it is based on published trials. Results of this systematic review and network meta-analysis will be submitted to a peer-reviewed journal for future publication. TRIAL REGISTRATION NUMBER: CRD42021278351.

Potential of food waste hydrolysate as an alternative carbon source for microbial oil synthesis.

Volatile fatty acids (VFAs) have great potential as cheap raw materials in microbial oil synthesis and reducing the cost of substrates is essential for the development of microbial oil biosynthesis. In this study, the food waste hydrolysate and synthetic VFAs media were both used as substrate to synthesis microbial oil. The optimal short-chain VFAs ratio for microbial oil synthesis is 20:5:5 and increasing the proportion of propionic acid is the key to obtaining odd fatty acids. The hydrolysate obtained from food waste under the total solid condition of 2:1 and pH 5 is the most suitable medium for microbial oil synthesis. The biological products obtained from food waste hydrolysate were comparable to synthetic VFAs media, obtaining a 34.02% of lipid content. Results prove that food waste hydrolysate has great potential as the available feedstock for microbial oil synthesis and a promising application value in food waste recycling.

Iron vacancies engineering of FexC@NC hybrids toward enhanced lithium-ion storage properties.

Defect engineering have profound influence on the energy storage properties of electrode hybrids by adjusting their intrinsic electronic characteristics. For iron carbide based materials, however, the effect of defect (especially cation vacancies) toward their electrochemical performance are still unclear. Herein, the feasible and scalable synthesis of FexC@NC with 3D honeycomb-like carbon architecture and abundant Fe vacancies via template etching is reported. Such structure enable outstanding lithium-ion storage properties owing to hierarchical pores, improved intrinsic electrochemical activity, as well as the introduction of more active sites. As a result, the FexC@NC-2 presents a high reversible specific capacity of 1079 mAh g-1after 1000 cycles. Moreover, an excellent cycling stability can be achieved via maintaining a high-capacity retention (689 mAh g-1, 98.4%) over 1000 cycles at 5 A g-1. This study provides a feasible strategy for developing high-performance hybrids with hierarchical pore and rich defects structures.

Characterization and Recombinant Genotypes of HIV-1 in Gansu Province, China.

It is important to monitor the diversity and evolution of HIV-1 genotypes, especially in some remote and undeveloped regions in China where the diversity and distribution of HIV-1 genotypes are not fully clear. To investigate the genotypes and distribution of HIV-1 in far Northwestern Gansu Province of China, we selected 220 HIV-1-positive plasma samples from the Center for Disease Control and Prevention (CDC) in Gansu from January 2016 to December 2018. The viral load of inclusion samples were over 1,000 copies per milliliter. The gag, pol, and env gene of HIV-1 were amplified by nested reverse transcription-polymerase chain reaction kit, sequenced, and then identified genotypes using HIV-BLAST tool and the neighbor-joining method. One hundred fifty of 220 inclusion samples were successfully determined HIV-1 genotypes. Our results show that circulating recombinant forms (CRF) 07_BC and CRF01_AE are predominant and accounted for 46.7% and 28.0%, respectively. Other HIV-1 subtypes and genotypes included B/B' (6.0%), CRF08_BC (4.0%), and C (1.3%). In addition, we reported CRF65_cpx and CRF55_01B subtypes in Gansu for the first time. Phylogenetic tree analysis showed that the sequences of different samples are scattered in different genotype groups, and no obvious aggregation occurs. Our results indicate the genetic variety and complexity of HIV-1 and provide critical information for HIV/AIDS control and prevention in Gansu Province.

Data for the lipase catalyzed synthesis of cyano-containing multi-substituted indoles.

The data presented here are related to the research paper entitled "Efficient Synthesis of Cyano-containing Multi-substituted Indoles Catalyzed by Lipase" [1]. In this data article, the lipase catalyzed synthetic procedures for the preparation of multi-substituted indoles and their derivatives were described. In total, 11 compounds were obtained and the optimum pH, reaction time and substrate ratio were screened through this study.

Efficient synthesis of cyano-containing multi-substituted indoles catalyzed by lipase.

BACKGROUND: Indoles are important bioactive compounds that have been extensively studied in organic chemistry. In this work, a green and efficient process for the synthesis of Indoles from 1,3-diketones with fumaronitrile was developed. RESULTS: Under optimal conditions (1,3-diketones (0.5 mmol), fumaronitrile (1 mmol), water (2 ml), lipase (15 mg), 30 °C, 24 h), high yields and satisfactory regioselectivity of cyano-containing multi-substituted indoles could be obtained when CRL (C. rugosa lipase) was used as the catalyst. CONCLUSION: This enzymatic method demonstrates the great potential for the synthesis of indoles and extends the application of enzyme in organic synthesis.

A Dual-Protein Cascade Reaction for the Regioselective Synthesis of Quinoxalines.

In this work, an efficient dual-protein (lipase and hemoglobin) system was successfully constructed for the regioselective synthesis of quinoxalines in water. A set of quinoxalines were obtained in high yields under optimal reaction conditions. This dual-protein method exhibited a regioselectivity higher than those of previously reported methods. This study not only provides a green and mild strategy for the synthesis of quinoxalines but also expands the application of lipase and hemoglobin in organic synthesis.