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5-Aminolevulinic acid (5-ALA) is a non-proteinogenic amino acid essential for synthesizing tetrapyrrole compounds, including heme, chlorophyll, cytochrome, and vitamin B12. As a plant growth regulator, 5-ALA is extensively used in agriculture to enhance crop yield and quality. The complexity and low yield of chemical synthesis methods have led to significant interest in the microbial synthesis of 5-ALA. Advanced strategies, including the: enhancement of precursor and cofactor supply, compartmentalization of key enzymes, product transporters engineering, by-product formation reduction, and biosensor-based dynamic regulation, have been implemented in bacteria for 5-ALA production, significantly advancing its industrialization. This article offers a comprehensive review of recent developments in 5-ALA production using engineered bacteria and presents new insights to propel the field forward.
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Currently, antibody drugs targeting programmed cell death ligand 1 (PD-L1) have achieved promising results in cancer treatment, while the development of small-molecule drugs lags behind. In this study, we designed and synthesized a series of PD-L1-degrading agents based on the PROTAC design principle, utilizing the PD-L1 inhibitor A56. Through systematic screening of ligands and linkers and investigating the structure-activity relationship of the degraders, we identified two highly active compounds, 9i and 9j. These compounds enhance levels of CD4+, CD8+, granzyme B, and perforin, demonstrating significant in vivo antitumor effects with a tumor growth inhibition (TGI) of up to 57.35 %. Both compounds facilitate the internalization of PD-L1 from the cell surface and promote its degradation through proteasomal and lysosomal pathways, while also maintaining inhibition of the PD-1/PD-L1 interaction. In summary, our findings provide a novel strategy and mechanism for developing biphenyl-based PROTAC antitumor drugs targeting and degrading PD-L1.
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Antineoplásicos , Antígeno B7-H1 , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Receptor de Morte Celular Programada 1 , Humanos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inibidores , Relação Estrutura-Atividade , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Estrutura Molecular , Animais , Proliferação de Células/efeitos dos fármacos , Camundongos , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral , Quimera de Direcionamento de ProteóliseRESUMO
3-methyl-4-nitrophenol (PNMC), a degradation product of organophosphorus insecticides and a byproduct of fuel combustion, exerting endocrine-disrupting effects. However, its impact on the meiotic process of oocytes remains unclear. In the present study, we investigated the effects of PNMC on meiotic maturation of mouse oocytes in vitro and related mechanisms. Morphologically, PNMC-exposure affected germinal vesicle breakdown (GVBD) and polar body extrusion (PBE) in mouse oocytes. Proteomic analysis suggested that PNMC-exposure altered oocyte protein expression that are associated with cytoskeleton, mitochondrial function and oxidative stress. Further studies demonstrated that PNMC-exposure disrupted spindle assembly and chromosome alignment, caused sustained activation of spindle assembly checkpoint (SAC), and arrested meiosis in oocytes. Specifically, PNMC-exposure interfered with the function of microtubule organizing centers (MTOCs) by significantly reducing phosphorylated mitogen activated protein kinase (p-MAPK) expression and disrupting the localization of Pericentrin and p-Aurora A, leading to spindle assembly failure. Besides, PNMC-exposure also increased α-tubulin acetylation, decreased microtubule stability. Moreover, PNMC-exposure impaired mitochondrial function, evidenced by abnormal mitochondrial distribution, decreased mitochondrial membrane potential and ATP levels, release of Cytochrome C into the cytoplasm, and elevated ROS levels. As a result, exposure to PNMC caused DNA damage and early apoptosis in oocytes. Fortunately, melatonin was able to promote oocyte maturation by removing the excessive ROS and enhancing mitochondrial function. These results highlight the adverse effects of PNMC on meiotic maturation, and underscore the protective role of melatonin against PNMC-induced damage.
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Meiose , Melatonina , Mitocôndrias , Oócitos , Fuso Acromático , Animais , Oócitos/efeitos dos fármacos , Melatonina/farmacologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Feminino , Fuso Acromático/efeitos dos fármacos , Meiose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes , Inseticidas/toxicidadeRESUMO
BACKGROUND: Previous studies have indicated a correlation between maternal imbalances in essential trace elements during pregnancy and the occurrence of spontaneous abortion (SA). Nonetheless, the impact of these elements from both partners and during the preconception period remains unexplored. OBJECTIVE: This study sought to evaluate the relationship between preconception essential trace elements and spontaneous abortion (SA) based on husband-wife dyads. METHODS: This study selected 390 couples with spontaneous abortion (SA) and 390 matched couples with live births from a preconception cohort of 33,687 couples. Urine samples collected prior to pregnancy were analyzed for ten essential trace elements (Se, Cr, Mo, Cu, Zn, Fe, Mn, V, Co, and Ni) using inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: Multivariate conditional logistic regression analysis identified that elevated concentrations of Zn (OR = 0.73) and Ni (OR = 0.69) in couples were associated with a reduced risk of SA, whereas elevated levels of Cr (OR = 1.30) and Mn (OR = 1.39) were linked to an increased risk. Restricted cubic spline models suggested a U-shaped association between couples' Cu and Co concentrations and SA. Bayesian Kernel Machine Regression further supported a U-shaped relationship between the mixture of ten elements and SA, showing significant protection at the 50th and 55th percentiles compared to the 10th percentile. Additionally, the effects of Cr, Zn, Mn, and Ni on SA varied when the concentrations of the other nine elements were held constant at their 25th, 50th, and 75th percentiles. Stratified analysis revealed that maternal Cu (OR = 0.43) and Fe (OR = 0.63) reduced the risk of SA when paternal Cu and Fe were in the lower quartile. Conversely, maternal Cu (OR = 2.03) and Fe (OR = 1.77) increased the risk of SA when paternal concentrations were in the higher quartile. Similar patterns were observed for Cr, Mn, Co, and Zn. CONCLUSION: Elevated urinary concentrations of Zn and Ni in couples were associated with a reduced risk of SA, while higher levels of Cr and Mn were linked to an increased risk. Cu, Co, and a mixture of ten essential trace elements exhibited a U-shaped relationship with SA. The impact of certain essential trace elements (Cu, Fe, Cr, Mn, Co, and Zn) on SA in one partner was influenced by their concentrations in the other partner.
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Recent studies on biphenyl-containing compounds, a type of PD-1/PD-L1 blocker which binds to PD-L1 and induces dimerisation, have focussed on its immune function. Herein, 10 novel biphenyl derivatives were designed and synthesised. The results of the CCK-8 showed that compounds have different anti-tumour activities for tumour cells in the absence of T cells. Particularly, 12j-4 can significantly induce the apoptosis of MDA-MB-231 cells (IC50 = 2.68 ± 0.27 µM). In further studies, 12j-4 has been shown to prevent the phosphorylation of AKT by binding to cytoplasmic PD-L1, which induces apoptosis in MDA-MB-231 cells through non-immune pathways. The inhibition of AKT phosphorylation restores the activity of GSK-3ß, ultimately resulting in the degradation of PD-L1. Besides, in vivo study indicated that 12j-4 repressed tumour growth in nude mice. As these biphenyls exert their anti-tumour effects mainly through non-immune pathways, they are worthy of further study as PD-L1 inhibitors.
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Compostos de Bifenilo , Neoplasias da Mama , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , Antígeno B7-H1 , Glicogênio Sintase Quinase 3 beta , Camundongos Nus , Neoplasias da Mama/tratamento farmacológico , Compostos de Bifenilo/farmacologiaRESUMO
Although high gravity brewing technology has been widely used for beer industries due to its economic benefits, yeast cells are subjected to multiple environmental stresses throughout the fermentation process. Eleven bioactive dipeptides (LH, HH, AY, LY, IY, AH, PW, TY, HL, VY, FC) were selected to evaluate their effects on cell proliferation, cell membrane defense system, antioxidant defense system and intracellular protective agents of lager yeast against ethanol-oxidation cross-stress. Results showed that the multiple stresses tolerance and fermentation performance of lager yeast were enhanced by bioactive dipeptides. Cell membrane integrity was improved by bioactive dipeptides through altering the structure of macromolecular compounds of the cell membrane. Intracellular reactive oxygen species (ROS) accumulation was significantly decreased by bioactive dipeptides, especially for FC, decreasing by 33.1%, compared with the control. The decrease of ROS was closely related to the increase of mitochondrial membrane potential, intracellular antioxidant enzyme activities including superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), and glycerol level. In addition, bioactive dipeptides could regulate the expression of key genes (GPD1, OLE1, SOD2, PEX11, CTT1, HSP12) to enhance the multilevel defense systems under ethanol-oxidation cross-stress. Therefore, bioactive dipeptides should be potentially efficient and feasible bioactive ingredients to improve the multiple stresses tolerance of lager yeast during high gravity fermentation.
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Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/metabolismo , Fermentação , Etanol/metabolismo , Cerveja , Peroxinas/metabolismo , Proteínas de Membrana , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMO
CLC-2 is a voltage-gated chloride channel that is widely expressed in mammalian tissues. In the central nervous system, CLC-2 appears in neurons and glia. Studies to define how this channel contributes to normal and pathophysiological function in the central nervous system raise questions that remain unresolved, in part due to the absence of precise pharmacological tools for modulating CLC-2 activity. Herein, we describe the development and optimization of AK-42, a specific small-molecule inhibitor of CLC-2 with nanomolar potency (IC50 = 17 ± 1 nM). AK-42 displays unprecedented selectivity (>1,000-fold) over CLC-1, the closest CLC-2 homolog, and exhibits no off-target engagement against a panel of 61 common channels, receptors, and transporters expressed in brain tissue. Computational docking, validated by mutagenesis and kinetic studies, indicates that AK-42 binds to an extracellular vestibule above the channel pore. In electrophysiological recordings of mouse CA1 hippocampal pyramidal neurons, AK-42 acutely and reversibly inhibits CLC-2 currents; no effect on current is observed on brain slices taken from CLC-2 knockout mice. These results establish AK-42 as a powerful tool for investigating CLC-2 neurophysiology.
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Canais de Cloreto/antagonistas & inibidores , Canais de Cloreto/química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Sítios de Ligação , Células CHO , Canais de Cloro CLC-2 , Linhagem Celular , Canais de Cloreto/genética , Canais de Cloreto/metabolismo , Cricetulus , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Hipocampo/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Simulação de Acoplamento Molecular , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp , Células Piramidais/efeitos dos fármacos , Células Piramidais/metabolismo , Bibliotecas de Moléculas Pequenas/metabolismo , Relação Estrutura-AtividadeRESUMO
Corynebacterium glutamicum porphobilinogen synthase (PBGS) is a metal enzyme with a hybrid active site metal binding sequence. In this study, the porphobilinogen synthase gene of C. glutamicum was cloned and heterogeneously expressed in Escherichia coli. C. glutamicum PBGS was purified, and its enzymatic characteristics were analyzed. The results showed that C. glutamicum PBGS is a Zn2+-dependent enzyme, and Mg2+ has allosteric regulation. The allosteric Mg2+ plays a vital role in forming the quaternary structure of C. glutamicum PBGS. Based on the ab initio predictive structure modeling of the enzyme and the molecular docking model of 5-aminolevulinic acid (5-ALA), 11 sites were selected for site-directed mutagenesis. When the hybrid active site metal binding site of C. glutamicum PBGS is converted into a cysteine-rich motif (Zn2+-dependent) or an aspartic acid-rich motif (Mg2+/K+-dependent), the enzyme activity is basically lost. Four residues, D128, C130, D132, and C140, in the metal binding site, were the binding sites of Zn2+ and the active center of the enzyme. The band migration, from the native PAGE, of five variants with mutations in the center of enzyme activity was the same as that of the variant enzymes as purified, individually adding two metal ion chelating agents. Their Zn2+ active center structures were abnormal, and the quaternary structure equilibrium was altered. The destroyed active center affects the construction of its quaternary structure. The quaternary structural balance between octamer and hexamer through dimers was regulated by the allosteric regulation of C. glutamicum PBGS. The enzyme activity was also affected by the change of the active site lid structure and (α ß)8-barrel structure caused by mutation. Structural changes in the variants were analyzed to understand C. glutamicum PBGS better.
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Corynebacterium glutamicum , Sintase do Porfobilinogênio , Sintase do Porfobilinogênio/genética , Sintase do Porfobilinogênio/química , Sintase do Porfobilinogênio/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Simulação de Acoplamento Molecular , Metais , Sítios de Ligação , Ácido AminolevulínicoRESUMO
Plants have evolved complex signalling networks to regulate growth and defence responses under an ever-changing environment. However, the molecular mechanisms underlying the growth-defence tradeoff are largely unclear. We previously reported that rice CALCIUM-DEPENDENT PROTEIN KINASE 18 (OsCPK18) and MITOGEN-ACTIVATED PROTEIN KINASE 5 (OsMPK5) mutually phosphorylate each other and that OsCPK18 phosphorylates and positively regulates OsMPK5 to suppress rice immunity. In this study, we found that OsCPK18 and its paralog OsCPK4 positively regulate plant height and yield-related traits. Further analysis reveals that OsCPK18 and OsMPK5 synergistically regulate defence-related genes but differentially regulate development-related genes. In vitro and in vivo kinase assays demonstrated that OsMPK5 phosphorylates C-terminal threonine (T505) and serine (S512) residues of OsCPK18 and OsCPK4, respectively. The kinase activity of OsCPK18T505D , in which T505 was replaced by aspartic acid to mimic T505 phosphorylation, displayed less calcium sensitivity than that of wild-type OsCPK18. Interestingly, editing the MAPK phosphorylation motif in OsCPK18 and its paralog OsCPK4, which deprives OsMPK5-mediated phosphorylation but retains calcium-dependent activation of kinase activity, simultaneously increases rice yields and immunity. This editing event also changed the last seven amino acid residues of OsCPK18 and attenuated its binding with OsMPK5. This study presents a new regulatory circuit that fine tunes the growth-defence tradeoff by modulating OsCPK18/4 activity and suggests that CRISPR/Cas9-mediated engineering phosphorylation pathways could simultaneously improve crop yield and immunity.
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Edição de Genes , Oryza , Oryza/genética , Fosforilação , Cálcio , Proteínas Quinases Ativadas por MitógenoRESUMO
Dissection of gene function requires sophisticated tools to monitor gene expression. Gene tagging with epitope peptides and fluorescent protein tags is a routine method to investigate protein expression using tag-specific antibodies and western blotting with tedious blotting and immunodetection steps. Nanoluciferase (NanoLuc) exhibits extremely bright bioluminescence and is engineered as a sensitive genetic reporter. Due to its small size and high bioluminescent activity, NanoLuc could be engineered to function as a novel protein tag that permits direct detection of tagged protein in the gel matrix (in-gel detection). In this study, we developed Gateway compatible vectors to tag proteins with NanoLuc in plants. We also tailored the in-gel detection conditions which can detect NanoLuc-tagged MPK3 from as low as 200 pg of total protein extracts. Compared to FLAG tag and western blotting-based detection, NanoLuc tag and optimized in-gel detection exhibit increased detection sensitivity but omit the blotting and immunodetection steps. We also demonstrated versatile applications of the NanoLuc-based in-gel detection method for protein expression analysis, probing protein-protein interactions by coimmunoprecipitation, and in vivo protein phosphorylation detection with Phos-tag gel electrophoresis. Finally, NanoLuc was used to tag the gene at its endogenous locus using the wheat dwarf virus replicon and CRISPR/Cas9-mediated gene targeting. Our data suggest that NanoLuc tag and in-gel detection permit fast detection of tagged protein with high sensitivity. The versatile NanoLuc toolkit and convenient in-gel detection method are expected to facilitate in vitro and in vivo protein analysis for plant functional genomics. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-021-01210-7.
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OBJECTIVE: Epilepsy is considered as a network disorder. However, it is unknown how normal brain activity develops into the highly synchronized discharging activity seen in disordered networks. This study aimed to explore the epilepsy brain network and the significant re-combined brain areas in childhood absence epilepsy (CAE). METHODS: Twenty-two children with CAE were recruited to study the neural source activity during ictal-onset and interictal periods at frequency bands of 1-30â¯Hz and 30-80â¯Hz with magnetoencephalography (MEG) scanning. Accumulated source imaging (ASI) was used to analyze the locations of neural source activity and peak source strength. RESULTS: Most of the participants had more active source activity locations in the ictal-onset period rather than in the interictal period, both at 1-30â¯Hz and 30-80â¯Hz. The frontal lobe (FL), the temporo-parietal junction (T-P), and the parietal lobe (PL) became the main active areas of source activity during the ictal period, while the precuneus (PC), cuneus, and thalamus were relatively inactive. CONCLUSIONS: Some brain areas become more excited and have increased source activity during seizures. These significant brain regions might be re-combined to form an epilepsy network that regulates the process of absence seizures. SIGNIFICANCE: The study confirmed that important brain regions are reorganized in an epilepsy network, which provides a basis for exploring the network mechanism of CAE development. Imaging findings may provide a reference for clinical characteristics.
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Epilepsia Tipo Ausência , Magnetoencefalografia , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Criança , Eletroencefalografia , Epilepsia Tipo Ausência/diagnóstico , Humanos , Imageamento por Ressonância Magnética , ConvulsõesRESUMO
INTRODUCTION: hERG block potency is widely used to calculate a drug's safety margin against its torsadogenic potential. Previous studies are confounded by use of different patch clamp electrophysiology protocols and a lack of statistical quantification of experimental variability. Since the new cardiac safety paradigm being discussed by the International Council for Harmonisation promotes a tighter integration of nonclinical and clinical data for torsadogenic risk assessment, a more systematic approach to estimate the hERG block potency and safety margin is needed. METHODS: A cross-industry study was performed to collect hERG data on 28 drugs with known torsadogenic risk using a standardized experimental protocol. A Bayesian hierarchical modeling (BHM) approach was used to assess the hERG block potency of these drugs by quantifying both the inter-site and intra-site variability. A modeling and simulation study was also done to evaluate protocol-dependent changes in hERG potency estimates. RESULTS: A systematic approach to estimate hERG block potency is established. The impact of choosing a safety margin threshold on torsadogenic risk evaluation is explored based on the posterior distributions of hERG potency estimated by this method. The modeling and simulation results suggest any potency estimate is specific to the protocol used. DISCUSSION: This methodology can estimate hERG block potency specific to a given voltage protocol. The relationship between safety margin thresholds and torsadogenic risk predictivity suggests the threshold should be tailored to each specific context of use, and safety margin evaluation may need to be integrated with other information to form a more comprehensive risk assessment.
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Canal de Potássio ERG1/antagonistas & inibidores , Medição de Risco/métodos , Torsades de Pointes/induzido quimicamente , Teorema de Bayes , Simulação por Computador , Humanos , Modelos Biológicos , Técnicas de Patch-Clamp , Bloqueadores dos Canais de Potássio/farmacologia , Segurança , Torsades de Pointes/fisiopatologiaRESUMO
Background Available methods to quantify regional dynamic thoracic function in thoracic insufficiency syndrome (TIS) are limited. Purpose To evaluate the use of quantitative dynamic MRI to depict changes in regional dynamic thoracic function before and after surgical correction of TIS. Materials and Methods Images from free-breathing dynamic MRI in pediatric patients with TIS (July 2009-August 2015) were retrospectively evaluated before and after surgical correction by using vertical expandable prosthetic titanium rib (VEPTR). Eleven volumetric parameters were derived from lung, chest wall, and diaphragm segmentations, and parameter changes before versus after operation were correlated with changes in clinical parameters. Paired analysis from Student t test on MRI parameters and clinical parameters was performed to detect if changes (from preoperative to postoperative condition) were statistically significant. Results Left and right lung volumes at end inspiration and end expiration increased substantially after operation in pediatric patients with thoracic insufficiency syndrome, especially right lung volume with 22.9% and 26.3% volume increase at end expiration (P = .001) and end inspiration (P = .002), respectively. The average lung tidal volumes increased after operation for TIS; there was a 43.8% and 55.3% increase for left lung tidal volume and right lung tidal volume (P < .001 for both), respectively. However, clinical parameters did not show significant changes from pre- to posttreatment states. Thoracic and lumbar Cobb angle were poor predictors of MRI tidal volumes (chest wall, diaphragm, and left and right separately), but assisted ventilation rating and forced vital capacity showed moderate correlations with tidal volumes (chest wall, diaphragm, and left and right separately). Conclusion Vertical expandable prosthetic titanium rib operation was associated with postoperative increases in all components of tidal volume (left and right chest wall and diaphragm, and left and right lung tidal volumes) measured at MRI. Clinical parameters did not demonstrate improvements in postoperative tidal volumes. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Paltiel in this issue.
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Imageamento por Ressonância Magnética/métodos , Insuficiência Respiratória/diagnóstico por imagem , Insuficiência Respiratória/cirurgia , Procedimentos Cirúrgicos Torácicos/métodos , Criança , Pré-Escolar , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Pulmão/cirurgia , Masculino , Estudos Prospectivos , Insuficiência Respiratória/fisiopatologia , Resultado do TratamentoRESUMO
Childhood absence epilepsy (CAE), the most common pediatric epilepsy syndrome, is usually treated with valproic acid (VPA) and lamotrigine (LTG) in China. This study aimed to investigate the ictal source locations and functional connectivity (FC) networks between the cortices and thalamus that are related to treatment response. Magnetoencephalography (MEG) data from 25 patients with CAE were recorded at 300 Hz and analyzed in 1-30 Hz frequency bands. Neuromagnetic sources were volumetrically scanned with accumulated source imaging. The FC networks between the cortices and thalamus were evaluated at the source level through a connectivity analysis. Treatment outcome was assessed after 36-66 months following MEG recording. The children with CAE were divided into LTG responder, LTG non-responder, VPA responder and VPA non-responder groups. The ictal source locations and cortico-thalamic FC networks were compared to the treatment response. The ictal source locations in the post-dorsal medial frontal cortex (post-DMFC, including the medial primary motor cortex and the supplementary sensorimotor area) were observed in all LTG non-responders but in all LTG responders. At 1-7 Hz, patients with fronto-thalamo-parietal/occipital (F-T-P/O) networks were older than those with fronto-thalamic (F-T) networks or other cortico-thalamic networks (p = 0.000). The duration of seizures in patients with F-T-P/O networks at 1-7 Hz was longer than that in patients with F-T networks or other cortico-thalamic networks (p = 0.001). The ictal post-DMFC source localizations suggest that children with CAE might experience initial LTG monotherapy failure. Moreover, the cortico-thalamo-cortical network is associated with age. Finally, the cortico-thalamo-cortical network consists of anterior and posterior cortices and might contribute to the maintenance of discharges.
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Anticonvulsivantes/uso terapêutico , Córtex Cerebral/fisiopatologia , Epilepsia Tipo Ausência/fisiopatologia , Rede Nervosa/fisiopatologia , Tálamo/fisiopatologia , Criança , Pré-Escolar , China , Epilepsia Tipo Ausência/tratamento farmacológico , Feminino , Substância Cinzenta/fisiopatologia , Humanos , Lamotrigina/uso terapêutico , Imageamento por Ressonância Magnética , Magnetoencefalografia , Masculino , Resultado do Tratamento , Ácido Valproico/uso terapêuticoRESUMO
Using multi-frequency magnetoencephalography (MEG) data, we investigated whether the effective connectivity (EC) network of patients with childhood absence epilepsy (CAE) is altered during the inter-ictal period in comparison with healthy controls. MEG data from 13 untreated CAE patients and 10 healthy controls were recorded. Correlation analysis and Granger causality analysis were used to construct an EC network at the source level in eight frequency bands. Alterations in the spatial pattern and topology of the network in CAE were investigated by comparing the patients with the controls. The network pattern was altered mainly in 1-4 Hz, showing strong connections within the frontal cortex and weak connections in the anterior-posterior pathways. The EC involving the precuneus/posterior cingulate cortex (PC/PCC) significantly decreased in low-frequency bands. In addition, the parameters of graph theory were significantly altered in several low- and high-frequency bands. CAE patients display frequency-specific abnormalities in the network pattern even during the inter-ictal period, and the frontal cortex and PC/PCC might play crucial roles in the pathophysiology of CAE. The EC network of CAE patients was over-connective and random during the inter-ictal period. This study is the first to reveal the frequency-specific alteration in the EC network during the inter-ictal period in CAE patients. Multiple-frequency MEG data are useful in investigating the pathophysiology of CAE, which can serve as new biomarkers of this disorder.
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Encéfalo/diagnóstico por imagem , Epilepsia Tipo Ausência/diagnóstico por imagem , Magnetoencefalografia , Encéfalo/fisiopatologia , Criança , Pré-Escolar , Epilepsia Tipo Ausência/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , MasculinoRESUMO
Small supernumerary marker chromosomes (sSMCs) are structurally abnormal rare chromosomes, difficult to characterize by karyotyping, and have been associated with minor dysmorphic features, azoospermia, and recurrent miscarriages. However, sSMC with a gonosomal trisomy has never been reported. Spermatocyte spreading and immunostaining were applied to detect meiotic prophase I progression, homologous chromosome pairing, synapsis, and recombination. In all the analyzed spermatocytes of the patient, the extra Y chromosome was not detected while the sSMC was present. The recombination frequency on autosomes was not affected, while the recombination frequencies on XY chromosome was significantly lower in the patient than in the controls. The meiotic prophase I progression was disturbed with significantly increased proportion of zygotene and decreased pachytene spermatocytes in the patients as compared with the controls. These findings highlight the importance of studies on meiotic behaviors in patients with an abnormal chromosomal constitution and provide an important framework for future studies, which may elucidate the impairment caused by sSMC in mammalian meiosis and fertility.
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Cromossomos Humanos X , Cromossomos Humanos Y , Prófase Meiótica I/genética , Recombinação Genética , Translocação Genética , Cariótipo XYY , Adulto , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/genética , Masculino , Espermatócitos/metabolismoAssuntos
Betacoronavirus , COVID-19 , China , Comorbidade , Infecções por Coronavirus , Humanos , Pandemias , Pneumonia Viral , Fatores de Risco , SARS-CoV-2RESUMO
Meaning in life, which has two possible sources: self-acceptance and social support, is essential to the mental health and development of college students. The current study aims to further clarify the symptom-level relations between meaning in life, self-acceptance, and social support, finding possible ways to improve meaning in the life of college students. Thousand three hundred and forty-eight Chinese college students completed the online questionnaire, including Self-acceptance Questionnaire, Social Support Rating Scale, and Meaning in Life Questionnaire and the data from 1,263 participants was used. Cross-sectional network analysis was used to examine the relation between self-acceptance and social support. We also explored the relation between dimensions of self-acceptance and social support and meaning in life using the flow network. The results show symptom "SlA" (self-acceptance) is the bridge symptom linking self-acceptance and social support. In the flow diagrams, "SlA" is directly and positively associated with the presence of meaning. Objective Support shares the strongest positive association with the search for meaning. The symptom "SIA" may be an important targeting symptom when trying to improve the meaning in life of college students. Additionally, social support is essential for college students to develop meaning in life.
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Sirtuin 5 (Sirt5), a member of the Sirtuin family, is involved in various intracellular biological processes. However, the function of Sirt5 in oocyte maturation has not been clearly elucidated. In this study, we observed that Sirt5 was persistently expressed during the meiotic division of mouse oocytes, with a notable decline in expression in aging oocytes. Sirt5 inhibition led to the failure of the first polar body extrusion and induced cell cycle arrest, indicative of unsuccessful oocyte maturation. Furthermore, Sirt5 inhibition was associated with the extrusion of abnormally large polar bodies, suggesting disrupted asymmetric oocyte division. Mechanistically, the inhibition of Sirt5 resulted in aberrant spindle assembly and disordered chromosome alignment in oocytes. Moreover, Sirt5 inhibition caused the spindle to be centrally located in the oocyte without migrating to the cortical region, consequently preventing the formation of the actin cap. Further investigation revealed that Sirt5 inhibition notably diminished the expression of phosphorylated cofilin and profilin1, while increasing cytoplasmic F-actin levels. These findings suggest that Sirt5 inhibition during oocyte maturation adversely affects spindle assembly and chromosome alignment and disrupts actin dynamics impairing spindle migration and contributing to the failure of symmetric oocyte division and maturation.