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1.
FASEB J ; 38(13): e23744, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38885031

RESUMO

The hypothalamic-pituitary-gonadal axis (HPG) is the key neuroendocrine axis involved in reproductive regulation. Brain and muscle ARNT-like protein 1 (Bmal1) participates in regulating the metabolism of various endocrine hormones. However, the regulation of Bmal1 on HPG and female fertility is unclear. This study aims to explore the regulation of female reproduction by Bmal1 via the HPG axis in mice. Bmal1-knockout (Ko) mice were generated using the CRISPR/Cas9 technology. The structure, function, and estrous cycle of ovarian in Bmal1 Ko female mice were measured. The key genes and proteins of the HPG axis involved in regulating female reproduction were examined through transcriptome analysis and then verified by RT-PCR, immunohistochemistry, and western blot. Furthermore, the fertility of female mice was detected after intervening prolactin (PRL) and progesterone (Pg) in Bmal1 ko mice. The number of offspring and ovarian weight were significantly lower in Bmal1-Ko mice than in wild-type (Wt) mice. In Bmal1-Ko mice, ovarian cells were arranged loosely and irregularly, and the total number of follicles was significantly reduced. No corpus luteum was found in the ovaries. Vaginal smears revealed that Bmal1-Ko mice had an irregular estrus cycle. In Bmal1-Ko mice, Star expression was decreased, PRL and luteinizing hormone (LH) levels were increased, and dopamine (DA) and Pg levels were decreased. Inhibition of PRL partially recovered the estrous cycle, corpus luteum formation, and Star expression in the ovaries. Pg supplementation promoted embryo implantation in Bmal1-Ko female mice. Bmal1 Ko increases serum PRL levels in female mice likely by reducing DA levels, thus affecting luteal formation, resulting in decreased Star expression and Pg production, hindering female reproduction. Inhibition of PRL or restoration of Pg can partially restore reproductive capacity in female Bmal1-Ko mice. Thus, Bmal1 may regulate female reproduction via the HPG axis in mice, suggesting that Bmal1 is a potential target to treat female infertility.


Assuntos
Fatores de Transcrição ARNTL , Ciclo Estral , Sistema Hipotálamo-Hipofisário , Camundongos Knockout , Ovário , Reprodução , Animais , Feminino , Fatores de Transcrição ARNTL/metabolismo , Fatores de Transcrição ARNTL/genética , Camundongos , Ovário/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Reprodução/fisiologia , Ciclo Estral/fisiologia , Prolactina/metabolismo , Progesterona/metabolismo , Fertilidade/fisiologia , Camundongos Endogâmicos C57BL
2.
Brief Bioinform ; 23(4)2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35656709

RESUMO

In the previous study, we developed the generalized drug-induced liver injury (DILI) prediction model-ResNet18DNN to predict DILI based on multi-source combined DILI dataset and achieved better performance than that of previously published described DILI prediction models. Recently, we were honored to receive the invitation from the editor to response the Letter to Editor by Liu Zhichao, et al. We were glad that our research has attracted the attention of Liu's team and they has put forward their opinions on our research. In this response to Letter to the Editor, we will respond to these comments.


Assuntos
Inteligência Artificial , Doença Hepática Induzida por Substâncias e Drogas , Humanos
3.
Brief Bioinform ; 23(1)2022 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-34882224

RESUMO

Drug-induced liver injury (DILI) has always been the focus of clinicians and drug researchers. How to improve the performance of the DILI prediction model to accurately predict liver injury was an urgent problem for researchers in the field of medical research. In order to solve this scientific problem, this research collected a comprehensive and accurate dataset of DILI with high recognition and high quality based on clinically confirmed DILI compound datasets, including 1446 chemical compounds. Then, the residual neural network with 18-layer by using more 5-layer blocks (ResNet18) with deep neural network (ResNet18DNN) model was proposed to predict DILI, which was an improved model for DILI prediction through vectorization of compound structure image. In predicting DILI, the ResNet18DNN learned greatly and outperformed the existing state-of-the-art DILI predictors. The results of DILI prediction model based on ResNet18DNN showed that the AUC (area under the curve), accuracy, recall, precision, F1-score and specificity of the training set were 0.973, 0.992, 0.995, 0.994, 0.995 and 0.975; those of test set were, respectively, 0.958, 0.976, 0.935, 0.947, 0.926 and 0.913, which were better than the performance of previously published described DILI prediction models. This method adopted ResNet18 embedding method to vectorize molecular structure images and the evaluation indicators of Resnet18DNN were obtained after 10 000 iterations. This prediction approach will greatly improve the performance of the predictive model of DILI and provide an accurate and precise early warning method for DILI in drug development and clinical medication.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Modelos Biológicos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Humanos , Estrutura Molecular , Redes Neurais de Computação
4.
Artigo em Inglês | MEDLINE | ID: mdl-38641368

RESUMO

BACKGROUND: Rapid eye movement (REM) sleep behaviour disorder (RBD) is one of the most common sleep problems and represents a key prodromal marker in Parkinson's disease (PD). It remains unclear whether and how basal ganglia nuclei, structures that are directly involved in the pathology of PD, are implicated in the occurrence of RBD. METHOD: Here, in parallel with whole-night video polysomnography, we recorded local field potentials from two major basal ganglia structures, the globus pallidus internus and subthalamic nucleus, in two cohorts of patients with PD who had varied severity of RBD. Basal ganglia oscillatory patterns during RBD and REM sleep without atonia were analysed and compared with another age-matched cohort of patients with dystonia that served as controls. RESULTS: We found that beta power in both basal ganglia nuclei was specifically elevated during REM sleep without atonia in patients with PD, but not in dystonia. Basal ganglia beta power during REM sleep positively correlated with the extent of atonia loss, with beta elevation preceding the activation of chin electromyogram activities by ~200 ms. The connectivity between basal ganglia beta power and chin muscular activities during REM sleep was significantly correlated with the clinical severity of RBD in PD. CONCLUSIONS: These findings support that basal ganglia activities are associated with if not directly contribute to the occurrence of RBD in PD. Our study expands the understanding of the role basal ganglia played in RBD and may foster improved therapies for RBD by interrupting the basal ganglia-muscular communication during REM sleep in PD.

5.
Langmuir ; 40(19): 9911-9925, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38688881

RESUMO

Groundwater infiltration into tunnels causes water to percolate through the fissure channels in the initial support shotcrete. This results in the dissolution and outflow of calcium hydroxide, a key product of cement hydration. This process significantly incurs the formation of crystallization blockages in the tunnel drainage systems. Optimizing the shotcrete mixing ratio is a feasible way to mitigate these blockages. Therefore, this study conducts calcium dissolution tests to investigate the impact of six admixtures, namely, antialkali agent, nanosilica, nanosilica carbonate, fly ash, sodium methyl silicate waterproofing agents, and silane waterproofing agents, on calcium dissolution resistance. Also, mechanical and microscopic tests are carried out to examine their impact on the strength and pore structure of the shotcrete. The objective of this study is to determine the optimal admixture for enhancing the calcium dissolution resistance of shotcrete. Results indicate that the antialkali agent significantly reduces the calcium leaching content of shotcrete. When the dosage is 14%, the calcium leaching amount is reduced by 68.4% in 28 days. Followed by nanosilica and silane waterproofing agents, with optimal dosages of 12 and 0.4%, respectively, the dissolution amount of calcium ions in shotcrete was reduced by 32.87 and 26.5%, respectively. Fly ash curing for 28 days can also reduce the calcium ion dissolution of shotcrete, while nanocalcium carbonate and sodium methyl silicate have little effect on the calcium dissolution of shotcrete. The antialkali agent with a strong calcium ion dissolution effect can improve the tensile strength of shotcrete under long-term curing conditions, which can be increased by 52%, but it compromises the growth of compressive strength. Nanosilica, fly ash, and silane waterproofing agents can improve both the compressive strength and tensile strength of shotcrete under long-term curing conditions. Specifically, at 28 days of curing, the compressive strength increased by 16.83, 28.8, and 20% and the tensile strength increased by 50.24, 60, and 64.5%. In addition, the microscopy results show that the antialkali agent, nanosilica, and silane waterproofing agents promote the hydration process of cement to form ettringite with a low and stable calcium-silicon ratio and reduce calcium hydroxide crystals. Nanosilica and silane waterproofing agents optimize the pore distribution in shotcrete by increasing beneficial pores, decreasing harmful pores, and reducing total porosity.

6.
Neurobiol Dis ; 182: 106143, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37146835

RESUMO

BACKGROUND: Sleep disturbances are highly prevalent in movement disorders, potentially due to the malfunctioning of basal ganglia structures. Pallidal deep brain stimulation (DBS) has been widely used for multiple movement disorders and been reported to improve sleep. We aimed to investigate the oscillatory pattern of pallidum during sleep and explore whether pallidal activities can be utilized to differentiate sleep stages, which could pave the way for sleep-aware adaptive DBS. METHODS: We directly recorded over 500 h of pallidal local field potentials during sleep from 39 subjects with movement disorders (20 dystonia, 8 Huntington's disease, and 11 Parkinson's disease). Pallidal spectrum and cortical-pallidal coherence were computed and compared across sleep stages. Machine learning approaches were utilized to build sleep decoders for different diseases to classify sleep stages through pallidal oscillatory features. Decoding accuracy was further associated with the spatial localization of the pallidum. RESULTS: Pallidal power spectra and cortical-pallidal coherence were significantly modulated by sleep-stage transitions in three movement disorders. Differences in sleep-related activities between diseases were identified in non-rapid eye movement (NREM) and REM sleep. Machine learning models using pallidal oscillatory features can decode sleep-wake states with over 90% accuracy. Decoding accuracies were higher in recording sites within the internus-pallidum than the external-pallidum, and can be precited using structural (P < 0.0001) and functional (P < 0.0001) whole-brain neuroimaging connectomics. CONCLUSION: Our findings revealed strong sleep-stage dependent distinctions in pallidal oscillations in multiple movement disorders. Pallidal oscillatory features were sufficient for sleep stage decoding. These data may facilitate the development of adaptive DBS systems targeting sleep problems that have broad translational prospects.


Assuntos
Estimulação Encefálica Profunda , Distonia , Distúrbios Distônicos , Doença de Parkinson , Humanos , Globo Pálido , Doença de Parkinson/complicações , Doença de Parkinson/terapia , Estimulação Encefálica Profunda/métodos , Sono
7.
Environ Microbiol ; 25(3): 675-688, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36527381

RESUMO

Microbial ammonia oxidation is vital to the nitrogen cycle. A biological process, called Dirammox (direct ammonia oxidation, NH3 →NH2 OH→N2 ), has been recently identified in Alcaligenes ammonioxydans and Alcaligenes faecalis. However, its transcriptional regulatory mechanism has not yet been fully elucidated. The present study characterized a new MocR-like transcription factor DnfR that is involved in the Dirammox process in A. faecalis strain JQ135. The entire dnf cluster was composed of 10 genes and transcribed as five transcriptional units, that is, dnfIH, dnfR, dnfG, dnfABCDE and dnfF. DnfR activates the transcription of dnfIH, dnfG and dnfABCDE genes, and represses its own transcription. The intact 1506-bp dnfR gene was required for activation of Dirammox. Electrophoretic mobility shift assays and DNase I footprinting analyses showed that DnfR has one binding site in the dnfH-dnfR intergenic region and two binding sites in the dnfG-dnfA intergenic region. Three binding sites of DnfR shared a 6-bp repeated conserved sequence 5'-GGTCTG-N17 -GGTCTG-3' which was essential for the transcription of downstream target genes. Cysteine and glutamate act as possible effectors of DnfR to activate the transcription of transcriptional units of dnfG and dnfABCDE, respectively. This study provided new insights in the transcriptional regulation mechanism of Dirammox by DnfR in A. faecalis JQ135.


Assuntos
Alcaligenes faecalis , Alcaligenes faecalis/química , Alcaligenes faecalis/genética , Alcaligenes faecalis/metabolismo , Amônia/metabolismo , Sítios de Ligação , Fatores de Transcrição/genética , Transcrição Gênica , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
8.
Appl Environ Microbiol ; 89(3): e0183522, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36815770

RESUMO

In bacteria, manganese homeostasis is controlled by import, regulation, and efflux. Here, we identified 2 Mn exporters, MetA and MetB (manganese efflux transporters A and B), in Riemerella anatipestifer CH-1, encoding a putative cation diffusion facilitator (CDF) protein and putative resistance-nodulation-division (RND) efflux pump, respectively. Compared with the wild type (WT), ΔmetA, ΔmetB, and ΔmetAΔmetB exhibited sensitivity to manganese, since they accumulated more intracellular Mn2+ than the WT under excess manganese conditions, while the amount of iron in the mutants was decreased. Moreover, ΔmetA, ΔmetB, and ΔmetAΔmetB were more sensitive to the oxidant NaOCl than the WT. Further study showed that supplementation with iron sources could alleviate manganese toxicity and that excess manganese inhibited bacterial cell division. RNA-Seq showed that manganese stress resulted in the perturbation of iron metabolism genes, further demonstrating that manganese efflux is critical for iron homeostasis. metA transcription was upregulated under excess manganese but was not activated by MetR, a DtxR family protein, although MetR was also involved in manganese detoxification, while metB transcription was downregulated under iron depletion conditions and in fur mutants. Finally, homologues of MetA and MetB were found to be mainly distributed in members of Flavobacteriaceae. Specifically, MetB represents a novel manganese exporter in Gram-negative bacteria. IMPORTANCE Manganese is required for the function of many proteins in bacteria, but in excess, manganese can mediate toxicity. Therefore, the intracellular levels of manganese must be tightly controlled. Manganese efflux transporters have been characterized in some other bacteria; however, their homologues could not be found in the genome of Riemerella anatipestifer through sequence comparison. This indicated that other types of manganese efflux transporters likely exist. In this study, we characterized 2 transporters, MetA and MetB, that mediate manganese efflux in R. anatipestifer in response to manganese overload. MetA encodes a putative cation diffusion facilitator (CDF) protein, which has been characterized as a manganese transporter in other bacteria, while this is the first observation of a putative resistance-nodulation-division (RND) transporter contributing to manganese export in Gram-negative bacteria. In addition, the mechanism of manganese toxicity was studied by observing morphological changes and by transcriptome sequencing. Taken together, these results are important for expanding our understanding of manganese transporters and revealing the mechanism of manganese toxicity.


Assuntos
Manganês , Riemerella , Manganês/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Ferro/metabolismo , Homeostase , Riemerella/genética , Riemerella/metabolismo , Estresse Oxidativo , Proteínas de Bactérias/metabolismo
9.
Brain ; 145(7): 2407-2421, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35441231

RESUMO

Freezing of gait is a debilitating symptom in advanced Parkinson's disease and responds heterogeneously to treatments such as deep brain stimulation. Recent studies indicated that cortical dysfunction is involved in the development of freezing, while evidence depicting the specific role of the primary motor cortex in the multi-circuit pathology of freezing is lacking. Since abnormal beta-gamma phase-amplitude coupling recorded from the primary motor cortex in patients with Parkinson's disease indicates parkinsonian state and responses to therapeutic deep brain stimulation, we hypothesized this metric might reveal unique information on understanding and improving therapy for freezing of gait. Here, we directly recorded potentials in the primary motor cortex using subdural electrocorticography and synchronously captured gait freezing using optoelectronic motion-tracking systems in 16 freely-walking patients with Parkinson's disease who received subthalamic nucleus deep brain stimulation surgery. Overall, we recorded 451 timed up-and-go walking trials and quantified 7073 s of stable walking and 3384 s of gait freezing in conditions of on/off-stimulation and with/without dual-tasking. We found that (i) high beta-gamma phase-amplitude coupling in the primary motor cortex was detected in freezing trials (i.e. walking trials that contained freezing), but not non-freezing trials, and the high coupling in freezing trials was not caused by dual-tasking or the lack of movement; (ii) non-freezing episodes within freezing trials also demonstrated abnormally high couplings, which predicted freezing severity; (iii) deep brain stimulation of subthalamic nucleus reduced these abnormal couplings and simultaneously improved freezing; and (iv) in trials that were at similar coupling levels, stimulation trials still demonstrated lower freezing severity than no-stimulation trials. These findings suggest that elevated phase-amplitude coupling in the primary motor cortex indicates higher probabilities of freezing. Therapeutic deep brain stimulation alleviates freezing by both decoupling cortical oscillations and enhancing cortical resistance to abnormal coupling. We formalized these findings to a novel 'bandwidth model,' which specifies the role of cortical dysfunction, cognitive burden and therapeutic stimulation on the emergence of freezing. By targeting key elements in the model, we may develop next-generation deep brain stimulation approaches for freezing of gait.


Assuntos
Estimulação Encefálica Profunda , Transtornos Neurológicos da Marcha , Doença de Parkinson , Núcleo Subtalâmico , Estimulação Encefálica Profunda/efeitos adversos , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/terapia , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia , Caminhada/fisiologia
10.
Aesthetic Plast Surg ; 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580565

RESUMO

BACKGROUND: Rhinoplasty is one of the most challenging plastic surgeries because it lacks a uniform standard for preoperative design or implementation. For a long time, rhinoplasties were done without an accurate consensus of aesthetic design between surgeons and patients before surgery and consequently brought unsatisfactory appearance for patients. In recent years, three-dimensional (3D) simulation has been used to visualize the preoperative design of rhinoplasty, and good results have been achieved. However, it still relied on individual aesthetics and experience. The preoperative design remained a huge challenge for inexperienced surgeons and could be time-consuming to perform manually. Therefore, we adopted artificial intelligence (AI) in this work to provide a new idea for automated and efficient preoperative nasal contour design. METHODS: We collected a dataset of 3D facial images from 209 patients. For each patient, both the original face and the manually designed face using 3D simulation software were included. The 3D images were transformed into point clouds, based on which we used the modified FoldingNet model for deep neural network training (by pytorch 1.12). RESULTS: The trained AI model gained the ability to perform aesthetic design automatically and achieved similar results to manual design. We analysed the 1027 facial features captured by the AI model and concluded two of its possible cognitive modes. One is to resemble the human aesthetic considerations while the other is to fulfil the given task in a special way of the machine. CONCLUSION: We presented the first AI model for automated preoperative 3D simulation of rhinoplasty in this study. It provided a new idea for the automated, individual and efficient preoperative design, which was expected to bring a new paradigm for rhinoplasty and even the whole field of plastic surgery. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

11.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2387-2395, 2023 May.
Artigo em Zh | MEDLINE | ID: mdl-37282868

RESUMO

As a traditional Chinese herb and functional food, the fruits of Lycium barbarum has been widely used for thousands of years in China. L. barbarum polysaccharides(LBPs) are predominant active components, which have immunomodulatory, antioxidant, hypoglycemic, neuroprotective, anti-tumor, and prebiotic activities. The molecular weight, monosaccharide composition, glycosidic bond, branching degree, protein content, chemical modification, and spatial structure of LBPs are closely related to their biological activity. Based on the previous studies of this research team, this paper systematically combed and integrated the research progress of structure, function, and structure-activity relationship of LBPs. At the same time, some problems restricting the clarification of the structure-activity relationship of LBPs were considered and prospected, hoping to provide references for the high value utilization of LBPs and in-depth exploration of their health value.


Assuntos
Antineoplásicos , Medicamentos de Ervas Chinesas , Lycium , Lycium/química , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Relação Estrutura-Atividade , Antioxidantes/farmacologia , Polissacarídeos/farmacologia , Polissacarídeos/química
12.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1510-1517, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37005838

RESUMO

Chalcone isomerase is a key rate-limiting enzyme in the biosynthesis of flavonoids in higher plants, which determines the production of flavonoids in plants. In this study, RNA was extracted from different parts of Isatis indigotica and reverse-transcribed into cDNA. Specific primers with enzyme restriction sites were designed, and a chalcone isomerase gene was cloned from I. indigotica, named IiCHI. IiCHI was 756 bp in length, containing a complete open reading frame and encoding 251 amino acids. Homology analysis showed that IiCHI was closely related to CHI protein of Arabidopsis thaliana and had typical active sites of chalcone isomerase. Phylogenetic tree analysis showed that IiCHI was classified into type Ⅰ CHI clade. Recombinant prokaryotic expression vector pET28a-IiCHI was constructed and purified to obtain IiCHI recombinant protein. In vitro enzymatic analysis showed that the IiCHI protein could convert naringenin chalcone into naringenin, but could not catalyze the production of liquiritigenin by isoliquiritigenin. The results of real-time quantitative polymerase chain reaction(qPCR) showed that the expression level of IiCHI in the aboveground parts was higher than that in the underground parts and the expression level was the highest in the flowers of the aboveground parts, followed by leaves and stems, and no expression was observed in the roots and rhizomes of the underground parts. This study has confirmed the function of chalcone isomerase in I. indigotica and provided references for the biosynthesis of flavonoid components.


Assuntos
Arabidopsis , Isatis , Isatis/genética , Proteínas de Plantas/metabolismo , Filogenia , Arabidopsis/genética , Flavonoides , Clonagem Molecular
13.
Neuroimage ; 258: 119389, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35714885

RESUMO

Low-frequency oscillations (LFOs, 28 Hz) in the subthalamic nucleus(STN) are known to reflect cognitive conflict. However, it is unclear if LFOs mediate communication and functional interactions among regions implicated in conflict processing, such as the motor cortex (M1), premotor cortex (PMC), and superior parietal lobule (SPL). To investigate the potential contribution of LFOs to cognitive conflict mediation, we recorded M1, PMC, and SPL activities by right subdural electrocorticography (ECoG) simultaneously with bilateral STN local field potentials (LFPs) by deep brain stimulation electrodes in 13 patients with Parkinson's disease who performed the arrow version of the Eriksen flanker task. Elevated cue-related LFO activity was observed across patients during task trials, with the earliest onset in PMC and SPL. At cue onset, LFO power exhibited a significantly greater increase or a trend of a greater increase in the PMC, M1, and STN, and less increase in the SPL during high-conflict (incongruent) trials than in low-conflict (congruent) trials. The local LFO power increases in PMC, SPL, and right STN were correlated with response time, supporting the notion that these structures are critical hubs for cognitive conflict processing. This power increase was accompanied by increased functional connectivity between the PMC and right STN, which was correlated with response time across subjects. Finally, ipsilateral PMC-STN Granger causality was enhanced during high-conflict trials, with direction from STN to PMC. Our study indicates that LFOs link the frontal and parietal cortex with STN during conflicts, and the ipsilateral PMC-STN connection is specifically involved in this cognitive conflict processing.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Conflito Psicológico , Humanos , Lobo Parietal
14.
Appl Environ Microbiol ; 88(6): e0226121, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35108103

RESUMO

Ammonia oxidation is an important process in both the natural nitrogen cycle and nitrogen removal from engineered ecosystems. Recently, a new ammonia oxidation pathway termed Dirammox (direct ammonia oxidation, NH3→NH2OH→N2) has been identified in Alcaligenes ammonioxydans. However, whether Dirammox is present in other microbes, as well as its genetic regulation, remains unknown. In this study, it was found that the metabolically versatile bacterium Alcaligenes faecalis strain JQ135 could efficiently convert ammonia into N2 via NH2OH under aerobic conditions. Genetic deletion and complementation results suggest that dnfABC is responsible for the ammonia oxidation to N2 in this strain. Strain JQ135 also employs aerobic denitrification, mainly producing N2O and trace amounts of N2, with nitrite as the sole nitrogen source. Deletion of the nirK and nosZ genes, which are essential for denitrification, did not impair the capability of JQ135 to oxidize ammonia to N2 (i.e., Dirammox is independent of denitrification). Furthermore, it was also demonstrated that pod (which encodes pyruvic oxime dioxygenase) was not involved in Dirammox and that AFA_16745 (which was previously annotated as ammonia monooxygenase and is widespread in heterotrophic bacteria) was not an ammonia monooxygenase. The MocR-family transcriptional regulator DnfR was characterized as an activator of the dnfABC operon with the binding motif 5'-TGGTCTGT-3' in the promoter region. A bioinformatic survey showed that homologs of dnf genes are widely distributed in heterotrophic bacteria. In conclusion, this work demonstrates that, besides A. ammonioxydans, Dirammox occurs in other bacteria and is regulated by the MocR-family transcriptional regulator DnfR. IMPORTANCE Microbial ammonia oxidation is a key and rate-limiting step of the nitrogen cycle. Three previously known ammonia oxidation pathways (i.e., nitrification, anaerobic ammonia oxidation [Anammox], and complete ammonia oxidation [Comammox]) are mediated by autotrophic microbes. However, the genetic foundations of ammonia oxidation by heterotrophic microorganisms have not been investigated in depth. Recently, a previously unknown pathway, termed direct ammonia oxidation to N2 (Dirammox), has been identified in the heterotrophic bacterium Alcaligenes ammonioxydans HO-1. This paper shows that, in the metabolically versatile bacterium Alcaligenes faecalis JQ135, the Dirammox pathway is mediated by dnf genes, which are independent of the denitrification pathway. A bioinformatic survey suggests that homologs of dnf genes are widely distributed in bacteria. These findings enhance the understanding of the molecular mechanisms of heterotrophic ammonia oxidation to N2.


Assuntos
Alcaligenes faecalis , Aerobiose , Alcaligenes faecalis/genética , Alcaligenes faecalis/metabolismo , Amônia/metabolismo , Desnitrificação , Ecossistema , Nitrificação , Nitritos/metabolismo , Nitrogênio/metabolismo
15.
J Neurooncol ; 160(1): 67-78, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36094613

RESUMO

AIM: Accumulating evidence suggests that lncRNAs are potential biomarkers and key regulators of tumor development and progression. However, the precise function of most lncRNAs in glioma remains unknown. In this study, we explored the role of long intergenic non-protein coding RNA 1018 (LINC01018) in human glioma. METHODS: Expression levels of LINC01018 and miR-182-5p in clinical glioma tissues and cell lines were detected by quantitative real-time PCR (qRT-PCR). Cell proliferation, migration, and invasion were determined by Cell Counting Kit-8 (CCK-8) assay and Transwell assay. Epithelial-mesenchymal transition (EMT) related proteins were measured by Western blotting. Direct relationship between LINC01018 and miR-182-5p was tested by dual-luciferase reporter assay, RNA immunoprecipitation assay (RIP), and rescue assays. Lastly, bioinformatics analyses were conducted to predict the downstream factors of LINC01018/miR-182-5p axis in glioma. RESULTS: LINC01018 was significantly down-regulated in glioma tissues and cell lines. Overexpression of LINC01018 dramatically inhibited cell proliferation, migration, and invasion and reverse EMT process in glioma. LINC01018 directly target to miR-182-5p. Forced up-regulation of miR-182-5p reversed the inhibitory effects on proliferative and metastatic abilities of glioma cells with LINC01018 overexpression. Lastly, the bioinformatics analyses revealed that LINC01018/miR-182-5p axis mediated a cluster of downstream genes (ADRA2C, RAB6B, RAB27B, RAPGEF5, STEAP2, TAGLN3, and UNC13C), which were potential key factors in the development of glioma. CONCLUSION: LINC01018 inhibits cell proliferation and metastasis in human glioma by targeting miR-182-5p, and should be considered as a potential therapeutic target in this cancer.


Assuntos
Glioma , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Movimento Celular/genética , Linhagem Celular Tumoral , Glioma/genética , Glioma/patologia , Proliferação de Células/genética
16.
Bioorg Chem ; 122: 105715, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35279552

RESUMO

In the present study, we completed the synthesis of a pyrazole derivative J-1063 and evaluated the kinase inhibitory activity of J-1063 activin receptor-like kinase 5 (ALK5) and p38α mitogen-activated protein (MAP) in the enzymatic assay. We evaluated anti-fibrotic effects of J-1063 on TGF-ß-induced hepatic stellate cells activation and TAA induced mice liver fibrosis. J-1063 showed much prior anti-fibrotic effects than those with LY2157299. Our data revealed that J-1063 exerted anti-fibrotic activity by inhibiting TGF-ßR1 (ALK5), which is likely related to the inhibition of TGF-ß--Smad signaling and NLRP3 inflammasome activation. The results suggest that J-1063 might be potential candidates for further anti-liver fibrosis drug development.


Assuntos
Cirrose Hepática , Proteínas Smad , Animais , Fibrose , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Camundongos , Pirazóis , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta
17.
Inflammopharmacology ; 30(4): 1335-1349, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35708797

RESUMO

Gout is a chronic disease caused by monosodium urate (MSU) crystal deposition in the joints and surrounding tissues. We examined the effects of Taxifolin, a natural flavonoid mainly existing in vegetables and fruits, on MSU-induced gout. Pretreatment with Taxifolin significantly reduced IL-1ß, Caspase-1 and HMGB1 levels, upregulation of autophagy-related protein, LC3, as well as improved phagocytosis of macrophages. This study indicated that Taxifolin-attenuated inflammatory response in MSU-induced acute gout model by decreasing pro-inflammatory cytokine production and promoting the autophagy and phagocytic capacity of macrophages. Dietary supplementation with Taxifolin induces the autophagy and attenuated inflammatory response, which in consequence modulates acute gout. A preventive strategy combining dietary interventions with Taxifolin may offer a potential therapeutic alternative to pharmacological treatment to reduce inflammatory response to gout.


Assuntos
Artrite Gotosa , Gota , Artrite Gotosa/induzido quimicamente , Artrite Gotosa/tratamento farmacológico , Autofagia , Gota/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Fagocitose , Quercetina/análogos & derivados , Ácido Úrico/metabolismo
18.
J Neuroradiol ; 49(2): 213-218, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34358534

RESUMO

BACKGROUND AND PURPOSE: To determine the neck management of tongue cancer, this study attempted to construct an artificial neural network (ANN)-assisted model based on computed tomography (CT) radiomics of primary tumors to predict neck lymph node (LN) status in patients with tongue squamous cell carcinoma (SCC). MATERIALS AND METHODS: Three hundred thirteen patients with tongue SCC were retrospectively included and randomly divided into training (60%), validation (20%) and internally independent test (20%) sets. In total, 1673 feature values were extracted after the semiautomatic segmentation of primary tumors and set as input layers of a classical 3-layer ANN incorporated with or without clinical LN (cN) status after dimension reduction. The receiver operating characteristic (ROC) curve, accuracy (ACC), sensitivity (SEN), specificity (SPE), area under curve (AUC) and Net Reclassification Index (NRI), were used to evaluate and compare the models. RESULTS: Four models with different settings were constructed. The ACC, SEN, SPE and AUC reached 84.1%, 93.1%, 76.5% and 0.943 (95% confidence interval: 0.891-0.996, p<.001), respectively, in the test set. The NRI of models compared with radiologists reached 40% (p<.001). The occult nodal metastasis rate was reduced from 30.9% to a minimum of 12.7% in the T1-2 group. CONCLUSION: ANN-based models that incorporated CT radiomics of primary tumors with traditional LN evaluation were constructed and validated to more precisely predict neck LN metastasis in patients with tongue SCC than with naked eyes, especially in early-stage cancer.


Assuntos
Carcinoma de Células Escamosas , Neoplasias da Língua , Carcinoma de Células Escamosas/diagnóstico por imagem , Humanos , Metástase Linfática/diagnóstico por imagem , Redes Neurais de Computação , Estudos Retrospectivos , Neoplasias da Língua/diagnóstico por imagem
19.
Zhongguo Zhong Yao Za Zhi ; 47(22): 6175-6182, 2022 Nov.
Artigo em Zh | MEDLINE | ID: mdl-36471942

RESUMO

This study aims to explore the molecular mechanism of Lycium barbarum polysaccharides(LBP) in alleviating premature ovarian failure(POF) in mice via the 5'-adenosine monophosphate activated protein kinase(AMPK)/silent information regulator 1(Sirt1) signaling pathway. The POF mouse model was established by D-galactose(D-gal) injection at the back. Six groups were set up, including a normal control group, a model group, a LBP group, a 3-MA(autophagy inhibitor 3-methyladenine) group, an AMPK inhibitor group, and a LBPAMPK inhibitor group, with 15 mice in each group. After 28 continuous days of administration, enzyme-linked immunosorbent assay(ELISA) was employed to determine the levels of sex hormones [estradiol(E_2), luteinizing hormone(LH), and follicle-stimulating hormone(FSH)] in serum. The ovarian mass coefficient was measured. Senescence-associated ß-Galactosidase(SA-ß-Gal) staining and hematoxylin-eosin(HE) staining were performed for observing the state of ovarian senescence and the morphological changes of the ovary. Immunohistochemical method was used to measure the expression of the autophagy marker LC3-Ⅱ in ovarian tissue. Western blot was employed to measure the expression levels of the senescence marker p16~(INK4 a), autophagy markers(LC3-Ⅱ and Beclin-1), the autophagy substrate p62, lysosome-associated membrane protein 2(LAMP2), and the proteins in the AMPK/Sirt1 pathway and mammalian target of rapamycin complex 1(mTORC1)/UNC-51-like kinase 1 Ser757 site(Ulk1 Ser757) pathway. Compared with the normal control group, the modeling of POF decreased the ovarian granulosa cells and follicles, led to the ovarian aging and severe sex hormone secretion disorders, weakened ovarian autophagy activity, and down-regulated the expression of proteins in the AMPK/Sirt1 pathway(P<0.05). Compared with the model group, the treatment with LBP increased ovarian granulosa cells and follicles, alleviated aging and sex hormone disorders, increased autophagy activity, and activated the AMPK/Sirt1 pathway(P<0.05). Both 3-MA and AMPK inhibitor can inhibit autophagy and aggravate ovarian damage and aging in mice. AMPK inhibitor can partially attenuate the role of LBP in promoting autophagy activation and alleviating aging and ovarian tissue damage(P<0.05). LBP can alleviate the symptoms of POF induced by D-gal by promoting the activation of AMPK/Sirt1 pathway.


Assuntos
Proteínas Quinases Ativadas por AMP , Autofagia , Lycium , Polissacarídeos , Insuficiência Ovariana Primária , Sirtuína 1 , Animais , Feminino , Humanos , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/efeitos dos fármacos , Hormônio Foliculoestimulante/sangue , Lycium/química , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Insuficiência Ovariana Primária/induzido quimicamente , Insuficiência Ovariana Primária/tratamento farmacológico , Sirtuína 1/metabolismo
20.
Zhongguo Zhong Yao Za Zhi ; 47(24): 6587-6595, 2022 Dec.
Artigo em Zh | MEDLINE | ID: mdl-36604907

RESUMO

Based on the transcriptome data of Isatis indigotica, a total of 110 putative glycosytransferases were identified. Through prokaryotic expression and enzymic activity assay in vitro, a novel lignan glycosyltransferase gene was screened out and named IiUGT349, which catalyzed lariciresinol into lariciresinol-4-O-ß-D-glucoside and lariciresinol-4'-O-ß-D-glucoside. Bioinformatics analysis suggested that IiUGT349 contained an open reading frame(ORF) of 1 401 bp encoding a protein of 467 amino acids. A protein analysis indicated that IiUGT349 have a predecited molecular weight of 52.77 kDa and pI of 5.96. Phylogenetic analysis showed that IiUGT349 belonging to UGT90 family shared low amino acid sequence identity with the reported lignan glycosyltransferases, which may represent a novel type of lignan glycosyltransferases. Quantitative real-time PCR(qRT-PCR) analysis showed that IiUGT349 was expressed in roots, stems, young leaves and leaves, with the highest expression level in stems. Further biochemical analysis showed that the optimal reaction time of IiUGT349 recombinant protein was 12 h and the optimal temperature was 45 ℃. Subcellular localization demonstrated that IiUGT349 was located in the cytoplasm and nucleus of plants. In this study, a new glucosyltransferase gene IiUGT349 from I. indigotica belonging to the UGT90 family was cloned, which laid a foundation to further investigate its' function and elucidate the lignan glycosides biosynthesis pathway and plays an important role for great significance for the synthetic biology of active lignan glycosides.


Assuntos
Isatis , Lignanas , Clonagem Molecular , Glucosídeos/metabolismo , Isatis/genética , Isatis/química , Lignanas/metabolismo , Filogenia , Glicosiltransferases/metabolismo
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