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1.
Cell Genom ; 4(5): 100553, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38688285

ABSTRACT

Single-cell RNA sequencing (scRNA-seq) and T cell receptor sequencing (TCR-seq) are pivotal for investigating T cell heterogeneity. Integrating these modalities, which is expected to uncover profound insights in immunology that might otherwise go unnoticed with a single modality, faces computational challenges due to the low-resource characteristics of the multimodal data. Herein, we present UniTCR, a novel low-resource-aware multimodal representation learning framework designed for the unified cross-modality integration, enabling comprehensive T cell analysis. By designing a dual-modality contrastive learning module and a single-modality preservation module to effectively embed each modality into a common latent space, UniTCR demonstrates versatility in connecting TCR sequences with T cell transcriptomes across various tasks, including single-modality analysis, modality gap analysis, epitope-TCR binding prediction, and TCR profile cross-modality generation, in a low-resource-aware way. Extensive evaluations conducted on multiple scRNA-seq/TCR-seq paired datasets showed the superior performance of UniTCR, exhibiting the ability of exploring the complexity of immune system.


Subject(s)
Receptors, Antigen, T-Cell , Transcriptome , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/immunology , Receptors, Antigen, T-Cell/metabolism , Humans , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Single-Cell Analysis , Sequence Analysis, RNA/methods , Machine Learning
2.
Org Lett ; 26(12): 2435-2439, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38501966

ABSTRACT

A photocatalytic cross-dehydrogenative coupling of diarylphosphine oxides with alcohols and phenols has been developed. Using organic dye Rose Bengal as the photocatalyst and air as the oxidant, the reaction proceeded smoothly at room temperature. Both alcohols and phenols were feasible, affording various organophosphinates in high yields. The absence of a halogenating reagent, the absence of a transition-metal catalyst, a green oxidant, and mild conditions make this strategy environmentally benign and sustainable. Mechanistic studies indicated that the reaction is enabled by the cooperation of photoredox catalysis and photosensitization.

3.
Crit Rev Oncol Hematol ; 197: 104320, 2024 May.
Article in English | MEDLINE | ID: mdl-38479585

ABSTRACT

The effects of ovarian stimulation on breast and gynecological tumor incidence remain controversial. Therefore, the aim of this meta-analysis was to study the risk of cancer in ovarian stimulation. Of the 22713 studies initially identified, 28 were eligible for inclusion. The results revealed that the impact of ovarian cancer (RR = 1.33, [1.05; 1.69]) and cervical cancer (RR = 0.67, [0.46; 0.97]) is significant among the overall effects. In subgroup analysis, in the nulliparous population (RR = 0.81 [0.68; 0.96]) was the protective factor for the breast cancer. In the Caucasians subgroup (RR = 1.45, [1.12; 1.88]), the ovarian cancer incidence was statistically significant. In the Asian subgroup (RR = 1.51, [1.00; 2.28]), the endometrial cancer incidence was statistically significant. In the subgroup of Asians (RR = 0.55 [0.44; 0.68]) and the multiparous population (RR = 0.31, [0.21; 0.46]), them can be the statistically protective factor for the cervical cancer.


Subject(s)
Breast Neoplasms , Ovulation Induction , Humans , Female , Breast Neoplasms/epidemiology , Breast Neoplasms/etiology , Ovulation Induction/adverse effects , Ovulation Induction/methods , Cohort Studies , Risk Factors , Genital Neoplasms, Female/epidemiology , Genital Neoplasms, Female/etiology , Incidence
4.
Anal Methods ; 16(8): 1244-1251, 2024 Feb 22.
Article in English | MEDLINE | ID: mdl-38319302

ABSTRACT

Stem cell preparations, as a new type of biotherapeutic product, should be subject to strict quality control in terms of cell safety. The testing of stem cell donors and blood products used in stem cell cultures, including but not limited to Treponema pallidum, is needed to reduce the risk of transmission of infectious diseases by stem cell medical products. In this study, a reference measurement procedure (RMP) was established based on digital PCR (dPCR). A homogeneous reference material (RM) of TP containing the tpp47 gene has been developed and characterized. Two dPCR assays (A and B) show ideal linearity within five orders of magnitude. The limit of quantification (LoQ) for both assays is 57 copies/reaction; the limits of detection (LoD) are 9.69 and 9.59 copies/reaction, respectively. The quantitative results of the established duplex dPCR assay are in good agreement. The RM of TP containing the tpp47 gene has been developed and characterized. The reference value with its expanded uncertainty is (2.21 ± 0.22) × 106 copies per µL determined by the established dPCR RMP. The developed dPCR was validated by applying a simulated stem cell matrix, and no impact was observed on the accuracy of dPCR. By providing an accurate reference value for the absolute copy number of the target gene, the developed RM can be used to improve the reliability of TP testing in the production of stem cell preparations and clinical diagnostics.


Subject(s)
Treponema pallidum , Treponema pallidum/genetics , Polymerase Chain Reaction/methods , Reproducibility of Results , Limit of Detection , Reference Values
5.
Org Lett ; 26(2): 498-502, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38194307

ABSTRACT

The convenient and precise preparation of N,N'-diarylhydrazides, especially from readily available raw materials, remains highly challenging. Here, a photoredox catalytic phosphine-mediated deoxygenative hydroacylation of azobenzenes with abundant and readily available carboxylic acids has been developed. With Ir[dF(CF3)ppy]2(dtbbpy)PF6 as the photocatalyst, the reactions proceeded smoothly in the presence of PPh3 under visible light irradiation, delivering various N,N'-diarylhydrazides in up to 92% yields. Mechanistic studies revealed that the reaction proceeds via photoredox catalysis and phosphoranyl-radical-mediated C-O bond cleavage of carboxylic acids.

6.
J Org Chem ; 89(3): 1669-1680, 2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38204383

ABSTRACT

A mild and eco-friendly visible-light-induced protocol for the hydroacylation of quinones with α-keto acids has been developed. In the absence of any catalyst or additive, the decarboxylative hydroacylation proceeded smoothly under visible-light irradiation at room temperature. A wide range of quinones and α-keto acids were well-tolerated and afforded hydroacylation products up to 88% isolated yield. The reaction can be scaled up, and the induced groups are useful for further synthetic applications. Preliminarily, mechanistic studies indicated that photoactive quinones absorb visible light to facilitate the transformation.

7.
Front Pharmacol ; 14: 1266803, 2023.
Article in English | MEDLINE | ID: mdl-37942489

ABSTRACT

Introduction: Chronic fatigue syndrome (CFS) is an increasingly common condition that is challenging to treat due to unclear etiology and a lack of consensus on clinical diagnosis and treatment guidance. Many affected people resorted to using traditional and complementary medicines (T&CMs). However, the evidence for T&CMs for CFS has been inconclusive and continues to evolve. The study aims to identify, summarize and assess the most recent evidence on the efficacy and safety of T&CMs for CFS. Methods: Randomized controlled trials (RCTs) investigating T&CMs for CFS published in English of Chinese between 1 January 2013 and 31 December 2022 were searched from 7 databases. RCTs comparing T&CMs with no treatment, placebo, or pharmacological medicine were included, irrespective of language or blinding. The Consolidated Standards of Reporting Trials Statement extensions for Chinese herbal medicine Formulas (CONSORT-CHM) and the Cochrane Collaboration's Risk of Bias tool were used to evaluate the quality and risk of bias of included studies. Results: A total of 62 RCTs investigating 43 types of T&CMs and involving 5,231 participants with CFS were included in this review. The primary outcome measures mainly included the scoring of fatigue symptoms using the validated tool Fatigue Scale-14 (FS-14) or the TCM syndrome score. The main interventions showing overall efficacy were Chaihu Guizhi Decoction and Buzhong Yiqi combined with Xiao Chaihu Decoction, and 148 ingredients were identified, including Astragali Radix, Glycyrrhizae Radix et Rhizoma, Atractylodis Macrocephalae Rhizoma, and Bupleuri Radix. The most significant effect was the improvement of fatigue, followed by TCM-diagnosed symptoms and other psychological conditions. No serious adverse effect had been reported. However, the quality of the RCTs included RCTs were found to be suboptimal, and the risk of bias remained uncertain. Conclusion: Some evidence from RCTs supported the efficacy and safety of T&CM in CFS. However, given the methodological and quality heterogenicity of the included studies, the recommendations of T&CMs in treating CFS remain inconclusive. To develop better quality evidence about T&CMs for CFS, future studies should employ more objective diagnosis standards and outcome measurements, larger sample size, and better bias control, and ensure the compliance with the corresponding reporting guidelines. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022362268, identifier CRD42022362268.

8.
Chin Med ; 18(1): 142, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37907925

ABSTRACT

BACKGROUND: Cancer-related fatigue (CRF) is an extremely common and long-term condition that affects the physical and mental health of oncology patients. While the treatment for CRF with western medicine and non-pharmacological therapy remains uncertain and challenging, traditional Chinese medicine (TCM) has become a trending option for the patients. Based on the findings from randomized controlled trials (RCTs), this study aims to identify and evaluate the evidence about the efficacy and safety of TCM for CRF. METHODS: A systematic literature search was conducted according to the PRISMA literature research guidelines. Seven electronic databases including PubMed, the Cochrane Library, Embase, Web of Science, Scopus, China National Knowledge Infrastructure (CNKI) and Wanfang database were searched to identify RCTs which investigated TCM in the treatment of CRF published since inception to December 2022. RCTs comparing TCM with no treatment, placebo, or pharmacological interventions were considered eligible for this review. The Consolidated Standards of Reporting Trials Statement extensions for Chinese herbal medicine Formulas (CONSORT-CHM) and the Cochrane Collaboration's Risk of Bias tool were used in this review to evaluate the quality and the risk of bias of all included trials. RESULTS: A total of 82 RCTs were included in this review, regardless of whether they were published in English or Chinese. After data extraction and results evaluation, 78 trials demonstrated overall efficacy in using TCM for CRF patients compared with the control group, in which 33 trials showed that the efficacy rate was statistically significant (p < 0.05 or p < 0.01). TCM was also shown to be beneficial in improving the scores of relevant scales (e.g., PFS, QoL, TCM syndrome score, other fatigue scales etc.) or physical tests indicators (e.g., cytokines, blood test etc.). The most common herbs found in Chinese medicine were Astragali Radix, Ginseng Radix and Codonopsis Radix. Some TCM products, such as Kangai Injection, Buzhong Yiqi Decoction and Shenqi Fuzheng Injection could provide a reference for medication in this review. A range of non-serious, reversible adverse effects associated with the use of TCM was also reported. However, the result of evaluation showed that none of the trials fully met all the CONSORT-CHM criteria, the quality of included trials was generally poor and the risk of bias was mostly uncertain. CONCLUSION: There is some evidence supporting the efficacy and safety of TCM in managing CRF in this systematic review. However, no clear conclusion can be made due to the inadequate reporting of efficacy and adverse reactions. In view of some concerns about the existing evidence after the evaluation, it is essential to standardize the comprehensive identification and efficacy measurement standards, improve the quality of RCTs and conduct more multicomponent therapies to provide an updated reference for CRF patients medication in the future. The protocol of this systematic review has been registered on PROSPERO (CRD42023413625). [ https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023413625 ].

9.
Chem Res Toxicol ; 36(11): 1717-1730, 2023 11 20.
Article in English | MEDLINE | ID: mdl-37839069

ABSTRACT

Drug-induced liver injury (DILI) is a significant cause of drug failure and withdrawal due to liver damage. Accurate prediction of hepatotoxic compounds is crucial for safe drug development. Several DILI prediction models have been published, but they are built on different data sets, making it difficult to compare model performance. Moreover, most existing models are based on molecular fingerprints or descriptors, neglecting molecular geometric properties and lacking interpretability. To address these limitations, we developed GeoDILI, an interpretable graph neural network that uses a molecular geometric representation. First, we utilized a geometry-based pretrained molecular representation and optimized it on the DILI data set to improve predictive performance. Second, we leveraged gradient information to obtain high-precision atomic-level weights and deduce the dominant substructure. We benchmarked GeoDILI against recently published DILI prediction models, as well as popular GNN models and fingerprint-based machine learning models using the same data set, showing superior predictive performance of our proposed model. We applied the interpretable method in the DILI data set and derived seven precise and mechanistically elucidated structural alerts. Overall, GeoDILI provides a promising approach for accurate and interpretable DILI prediction with potential applications in drug discovery and safety assessment. The data and source code are available at GitHub repository (https://github.com/CSU-QJY/GeoDILI).


Subject(s)
Chemical and Drug Induced Liver Injury , Humans , Drug Development , Drug Discovery , Machine Learning , Neural Networks, Computer
10.
J Assist Reprod Genet ; 40(12): 2933-2943, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37751120

ABSTRACT

PURPOSE: Providing feasible preimplantation genetic testing strategies for monogenic disorders (PGT-M) for prevention and control of genetic cancers. METHODS: Inclusion of families with a specific pathogenic mutation or a clear family history of genetic cancers. Identification of the distribution of hereditary cancer-related mutations in families through genetic testing. After a series of assisted reproductive measures such as down-regulation, stimulation, egg retrieval, and in vitro fertilization, a biopsy of trophectoderm cells from a blastocyst was performed for single-cell level whole-genome amplification (WGA). Then, the detection of chromosomal aneuploidies was performed by karyomapping. Construction of a haplotype-based linkage analysis to determine whether the embryo carries the mutation. Meanwhile, we performed CNV testing. Finally, embryos can be selected for transfer, and the results will be verified in 18-22 weeks after pregnancy. RESULTS: Six couples with a total of 7 cycles were included in our study. Except for cycle 1 of case 5 which did not result in a transferable embryo, the remaining 6 cycles produced transferable embryos and had a successful pregnancy. Four couples have had amniotic fluid tests to confirm that the fetus does not carry the mutation, while 1 couple was not tested due to insufficient pregnancy weeks. And the remaining couples had to induce labor due to fetal megacystis during pregnancy. CONCLUSION: Our strategy has been proven to be feasible. It can effectively prevent transmission of hereditary cancer-related mutations to offspring during the prenatal stage.


Subject(s)
Neoplasms , Preimplantation Diagnosis , Pregnancy , Female , Humans , Preimplantation Diagnosis/methods , Haplotypes/genetics , Genetic Predisposition to Disease , Genetic Testing/methods , Aneuploidy , Blastocyst/physiology , Neoplasms/diagnosis , Neoplasms/genetics , Neoplasms/prevention & control
11.
J Int Med Res ; 51(6): 3000605231180039, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37340721

ABSTRACT

OBJECTIVE: Oral lichen planus (OLP) is a T cell-mediated inflammatory condition in the oral cavity. Mucosal-associated invariant T (MAIT) cells are gaining more relevance in immune diseases because they can be activated by cytokines without T cell receptor stimulation. Herein, we tested the effect of interleukin-23 (IL-23) on the activation status of OLP MAIT cells. METHODS: Peripheral blood mononuclear cells (PBMCs) isolated from OLP patients were stimulated by IL-23 in the absence or presence of phorbol myristate acetate (PMA) and ionomycin. The activation status of MAIT cells was analyzed by flow cytometry after staining for CD3, CD4, CD8, CD161, TCR Vα7.2, and CD69. RESULTS: The fraction of MAIT cells in OLP peripheral blood was approximately 0.38% to 3.97%, and CD8+ subpopulations overwhelmed CD4+ cells. The mean percentages of OLP MAIT cells in PBMCs and CD8+MAIT cells in MAIT cells were approximately 40%. PMA and ionomycin significantly increased CD69 expression on OLP T cells, MAIT cells, and CD8+MAIT cells. Cells with enhanced activation had different responsiveness to exogenous IL-23, showing increased CD69 expression on OLP T cells, decreased CD69 on OLP CD8+MAIT cells, and no significant change on OLP MAIT cells. CONCLUSIONS: IL-23 showed different effects on the activation status of OLP MAIT cells and CD8+MAIT cells.


Subject(s)
Interleukin-23 , Lichen Planus, Oral , Mucosal-Associated Invariant T Cells , Humans , Interleukin-23/pharmacology , Ionomycin/pharmacology , Leukocytes, Mononuclear , Lichen Planus, Oral/metabolism , Mucosal-Associated Invariant T Cells/metabolism
12.
J Assist Reprod Genet ; 40(7): 1735-1746, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37154837

ABSTRACT

PURPOSE: Currently, owing to the limitations of high-throughput sequencing depth and the allele dropout caused by the whole-genome amplification, detection of chromosomal variants in embryos with CNVs <5 Mb is unsatisfactory at the single-cell level using only conventional sequencing methods. Therefore, here we aimed to use a strategy of preimplantation genetic testing for monogenic (PGT-M) to compensate for the shortcomings of conventional sequencing methods. The purpose of this study is to report the effectiveness of haplotype linkage analysis by karyomapping for preimplantation diagnosis microdeletion diseases. METHODS: Six couples carrying chromosomal microdeletions associated with X-linked ichthyosis were recruited, and all couples entered the PGT process. Multiple displacement amplification (MDA) method was used to amplify the whole-genome DNA of trophectoderm cells. Then karyomapping based on single nucleotide polymorphism (SNP) was used for haplotype linkage analysis to detect alleles carrying microdeletions, and CNVs of embryos were identified to determine euploid identity. Amniotic fluid tests were performed in the second trimester to verify the PGT-M results. RESULTS: All couples were tested for chromosomal microdeletions, with deletion fragments ranging in size from 1.60 to 1.73 Mb, and one partner in each couple did not carry the microdeletion. Three couples successfully underwent PGT-M assisted conception and obtained healthy live births. CONCLUSION: This study shows that haplotype linkage analysis by karyomapping could effectively detect the carrier status of embryos with microdeletions at the single-cell level. This approach may be applied to the preimplantation diagnosis of various chromosomal microvariation diseases.


Subject(s)
Chromosome Disorders , Ichthyosis , Preimplantation Diagnosis , Pregnancy , Female , Humans , Haplotypes/genetics , Genetic Testing/methods , Preimplantation Diagnosis/methods , Alleles , Aneuploidy
13.
J Org Chem ; 87(21): 14536-14543, 2022 Nov 04.
Article in English | MEDLINE | ID: mdl-36269896

ABSTRACT

We report a cathodic reduction-dominated electrochemical approach for the hydrogenation of azobenzenes in dichloromethane. With cheap and readily available N,N-diisopropylethylamine as a catalytic mediator, the reaction proceeded smoothly in a simple undivided cell under constant-current electrolysis. A series of azobenzenes were successfully reduced to the corresponding hydrazobenzenes in moderate to high yields at room temperature. Preliminarily mechanistic studies indicate that solvent dichloromethane acts as a hydrogen source. The use of a common solvent as a hydrogen source, no need for stoichiometric mediators or metallic reductants, and mild conditions make this work a more straightforward and sustainable protocol for hydrogenation of azobenzenes.

14.
Front Oncol ; 12: 905955, 2022.
Article in English | MEDLINE | ID: mdl-35912199

ABSTRACT

A thyroid nodule, which is defined as abnormal growth of thyroid cells, indicates excessive iodine intake, thyroid degeneration, inflammation, and other diseases. Although thyroid nodules are always non-malignant, the malignancy likelihood of a thyroid nodule grows steadily every year. In order to reduce the burden on doctors and avoid unnecessary fine needle aspiration (FNA) and surgical resection, various studies have been done to diagnose thyroid nodules through deep-learning-based image recognition analysis. In this study, to predict the benign and malignant thyroid nodules accurately, a novel deep learning framework is proposed. Five hundred eight ultrasound images were collected from the Third Hospital of Hebei Medical University in China for model training and validation. First, a ResNet18 model, pretrained on ImageNet, was trained by an ultrasound image dataset, and a random sampling of training dataset was applied 10 times to avoid accidental errors. The results show that our model has a good performance, the average area under curve (AUC) of 10 times is 0.997, the average accuracy is 0.984, the average recall is 0.978, the average precision is 0.939, and the average F1 score is 0.957. Second, Gradient-weighted Class Activation Mapping (Grad-CAM) was proposed to highlight sensitive regions in an ultrasound image during the learning process. Grad-CAM is able to extract the sensitive regions and analyze their shape features. Based on the results, there are obvious differences between benign and malignant thyroid nodules; therefore, shape features of the sensitive regions are helpful in diagnosis to a great extent. Overall, the proposed model demonstrated the feasibility of employing deep learning and ultrasound images to estimate benign and malignant thyroid nodules.

15.
Inflamm Res ; 71(9): 1041-1054, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35781343

ABSTRACT

OBJECTIVE: Mucosal-associated invariant T (MAIT) cells are unique innate-like T cells that are abundant in humans, accounting for 1-10% of circulating T cells and about 2% of total T cells in human oral cavity. MAIT cells can mount a strong immune response quickly without exogenous antigens and undergo a phenotypic transformation in the development of diseases. They produce cytokines involved in the Th1 and Th17 immune response and cytotoxic proteins, promote the dysfunction of autoreactive B cell and inhibit the function of NK cells. MAIT cells have been widely explored in autoimmune diseases, inflammatory diseases and tumors, and these mechanisms may also be involved in the pathogenesis of some oral diseases, while MAIT cells have not been systematically discussed in oral diseases. METHODS: We searched PubMed/MEDLINE, EMBASE and Microsoft Bing databases to review and analyze relevant literatures on the impact of MAIT cells in the pathogenesis of human oral diseases. CONCLUSION: Collected evidence elucidated the characteristics of MAIT cells and emphasized the potential roles of MAIT cells in oral lichen planus (OLP), chronic graft-versus-host disease (cGVHD), oral squamous cell carcinoma (OSCC), apical periodontitis (AP) and primary Sjogren's syndrome (pSS).


Subject(s)
Carcinoma, Squamous Cell , Lichen Planus, Oral , Mouth Neoplasms , Mucosal-Associated Invariant T Cells , Carcinoma, Squamous Cell/metabolism , Cytokines/metabolism , Humans
16.
Hortic Res ; 9: uhac102, 2022.
Article in English | MEDLINE | ID: mdl-35795388

ABSTRACT

Mango (Mangifera indica L.) is a climacteric tropical fruit consumed around the world. Although ethylene and abscisic acid (ABA) have been considered to be stimulators that trigger mango fruit ripening, their regulation mechanisms in modulating mango fruit ripening remain uncertain. In this study, we performed integrative analyses of metabolome and transcriptome data combined with a series of physiological and experimental analyses in the 'Keitt' mango, and we characterized changes in accumulation of specific metabolites at different stages during fruit development and ripening, which were strongly correlated with transcriptional changes and embodied physiological changes as well as taste formation. Specifically, we found that ABA, rather than ethylene, was highly associated with mango ripening, and exogenous ABA application promoted mango fruit ripening. Transcriptomic analysis identified diverse ripening-related genes involved in sugar and carotenoid biosynthesis and softening-related metabolic processes. Furthermore, networks of ABA- and ripening-related genes (such as MiHY5, MiGBF4, MiABI5, and MibZIP9) were constructed, and the direct regulation by the key ABA-responsive transcription factor MiHY5 of ripening-related genes was experimentally confirmed by a range of evidence. Taken together, our results indicate that ABA plays a key role in directly modulating mango fruit ripening through MiHY5, suggesting the need to reconsider how we understand ABA function in modulating climacteric fruit ripening.

17.
Int J Mol Sci ; 23(6)2022 Mar 19.
Article in English | MEDLINE | ID: mdl-35328749

ABSTRACT

Calotropis gigantea is often found in mining areas with heavy metal pollution. However, little is known about the physiological and molecular response mechanism of C. gigantea to Cd stress. In the present study, Cd tolerance characteristic of C. gigantea and the potential mechanisms were explored. Seed germination test results showed that C. gigantea had a certain Cd tolerance capacity. Biochemical and transcriptomic analysis indicated that the roots and leaves of C. gigantea had different responses to early Cd stress. A total of 176 and 1618 DEGs were identified in the roots and leaves of C. gigantea treated with Cd compared to the control samples, respectively. Results indicated that oxidative stress was mainly initiated in the roots of C. gigantea, whereas the leaves activated several Cd detoxification processes to cope with Cd, including the upregulation of genes involved in Cd transport (i.e., absorption, efflux, or compartmentalization), cell wall remodeling, antioxidant system, and chelation. This study provides preliminary information to understand how C. gigantea respond to Cd stress, which is useful for evaluating the potential of C. gigantea in the remediation of Cd-contaminated soils.


Subject(s)
Calotropis , Soil Pollutants , Cadmium/analysis , Cadmium/toxicity , Calotropis/genetics , Plant Leaves/chemistry , Plant Leaves/genetics , Plant Roots/chemistry , Plant Roots/genetics , Soil Pollutants/toxicity , Transcriptome
18.
Chemosphere ; 296: 134045, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35183585

ABSTRACT

Screening or breeding exceptional plant species for heavy metal phytoremediation is as important as adopting feasible measures to enhance phytoremediation efficiency, which are largely based on clarifying the mechanisms of heavy metal tolerance and accumulation by plants. In this study, cadmium (Cd) and lead (Pb) tolerance and accumulation characteristics of Rheum officinale, R. palmatum, and R. tanguticum were analysed to assess their phytoremediation potential. The seed germination test indicated that these three rhubarb species could tolerate 10 mg L-1 Cd and 100 mg L-1 Pb. However, when sown in Cd- and Pb-contaminated soil, all three rhubarb species exhibited a relatively high Cd accumulation capacity but a considerably low Pb accumulation capacity according to the bioconcentration factors of Cd (0.42-0.47 in shoots and 0.11-0.15 in roots) and Pb (0.004-0.008 in shoots and 0.007-0.013 in roots). The high Cd translocation factors (3.04-4.24) indicated that these three rhubarb species were suitable for Cd phytoextraction. The changes in rhizospheric physicochemical indices were generally similar among the three rhubarb plants in comparison with those of the unplanted soil. However, differential indicator rhizobacteria were identified for the three rhubarb plants, which may be primarily attributed to their different root system characteristics. These enriched rhizobacteria included many plant growth-promoting bacteria, and several of them were also involved in regulating heavy metal uptake by plants, indicating that three rhubarb species likely recruit differentially beneficial rhizobacteria to maintain plant growth and vitality and to regulate heavy metal uptake in the Cd- and Pb-polluted soil. This study identifies new candidate plant resources for the phytoremediation of Cd-polluted soils and provides novel insights into understanding the interactions among heavy metals, rhizobacteria, and plants.


Subject(s)
Metals, Heavy , Rheum , Soil Pollutants , Biodegradation, Environmental , Cadmium/analysis , Lead/analysis , Metals, Heavy/analysis , Plant Breeding , Plant Roots/chemistry , Plants , Rhizosphere , Soil , Soil Pollutants/analysis
19.
Org Lett ; 24(7): 1530-1535, 2022 Feb 25.
Article in English | MEDLINE | ID: mdl-35156831

ABSTRACT

A visible-light-promoted aerobic oxyphosphorylation of α-diazoesters and H-phosphine oxides has been developed. Using air as the oxygen source, the reaction proceeded smoothly at room temperature under blue-light irradiation. The α-diazoesters, molecular oxygen, and H-phosphine oxides are conveniently incorporated into a C-O-P(O) unit in one step. The preliminary mechanistic studies indicated that a light-triggered radical process is involved. The developed strategy shows the unrevealed reactivity of diazo compounds with H-phosphine oxides and has potential value in synthetic applications.

20.
Chem Commun (Camb) ; 58(9): 1382-1385, 2022 Jan 27.
Article in English | MEDLINE | ID: mdl-34989725

ABSTRACT

Herein, we report a cobalt-catalyzed α-hydroxymethylation of amides with methanol under mild conditions. Using CoCl2·6H2O as an inexpensive and efficient catalyst, some important bioactive ß-hydroxyamides were obtained in moderate to excellent yields. The developed method features a wide substrate scope and good functional group tolerance. In addition, anticholinergic tropicamide was easily synthesized in this way.

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