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Automotive interiors have been identified as significant sources of various chemicals, yet their occupational hazards for end-of-life vehicle (ELV) dismantlers remain poorly characterized. Herein, eight classes of plasticizers, including 11 phthalates esters (PAEs) and 16 non-phthalates esters (NPAEs), were detected in dust samples from inside and outside ELV dismantling workshops. Moreover, indoor dust from ordinary households and university dormitories was compared. The indoor dust from the ELV dismantling workshops contained the highest concentrations of plasticizers (median: 594 µg/g), followed by ordinary households (296 µg/g), university dormitories (186 µg/g), and outdoor dust (157 µg/g). PAEs remained the dominant plasticizers, averaging 11.7-fold higher than their NPAE alternatives. Specifically, diisononyl phthalate and trioctyl trimellitate were notably elevated in workshop dust, being 15.5 and 4.78 times higher, respectively, than in ordinary household dust, potentially indicating their association with ELV dismantling activities. The estimated daily intake of occupational ELV dismantling workers was up to five times higher than that of the general population. Moreover, certain dominant NPAEs demonstrated nuclear receptor interference abilities comparable to typical PAEs, suggesting potential toxic effects. This study is the first to demonstrate that ELV dismantling activities contribute to the co-emission of PAEs and NPAEs, posing a substantial risk of exposure to workers, which warrants further investigation.
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Introduction: The digital financial inclusion (DFI) provides opportunities to improve the relative capacity to pay for healthcare services by rural residents who are usually underserved by traditional finance in China. This paper provides empirical evidence on how the development of DFI affects the healthcare expenditure disparities between urban and rural residents. Methods: We employed the fixed effects model and instrumental variable method to estimate the impact of DFI on the Theil index of urban-rural disparities in healthcare expenditures, using panel data from 31 provinces (2011 ~ 2020) in China. We further adopted a moderating effect model to test whether the intensity of the impact would vary depending on the level of local government health expenditures. Results: The results suggest a negative association between the development level of DFI and the urban-rural healthcare expenditure disparities in China. For every 1% increase in the DFI index, the Theil index of urban-rural disparities in healthcare expenditures would fall by 0.0013. After changing the measurement method for the dependent variable and adjusting the sample, the results remain robust. Moreover, the result of the moderating effect model indicates that, a high level of government health expenditures is conducive to the impact of DFI. Discussion: Our research reveals that DFI plays an important role in bridging the urban-rural gap in healthcare expenditures. This finding provides new information for addressing the issue of urban-rural healthcare inequality in China. Chinese government needs to accelerate the construction of digital infrastructure and increase the penetration rate of digital tools in rural areas to promote the beneficial effects of DFI. Additionally, it is also necessary for local government to address the unbalanced allocation of medical resources between urban and rural areas, especially the shortage of rural human resources.
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Gastos em Saúde , Disparidades em Assistência à Saúde , População Rural , População Urbana , China , Humanos , Gastos em Saúde/estatística & dados numéricos , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Disparidades em Assistência à Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde/economiaRESUMO
SO2 derivatives, sulfite/bisulfite, are widely employed in both the food processing and drug synthesis industries. Despite their widespread application, excessive levels of sulfite/bisulfite can negatively impact human health. Most probes for detecting sulfite/bisulfite are restricted by their fluorescence within the visible spectrum range and poor solubility in aqueous solution, which limit their use in food testing and biological imaging. Herein, a near-infrared probe comprising of the cyanopyridine cyanine skeleton, 4-((Z)-2-((E)-2-chloro-3-(2-cyano-2-(1-methylpyridine-4(1H)-ylidene)ethylidene)cyclohex-1-en-1-yl)-1-cyanovinyl)-1-methylpyridin-1-ium (abbreviated as CCP), was developed. This probe enables precise quantification of bisulfite (HSO3-) in almost pure buffered solutions, showing a near-infrared fluorescence emission at 784 nm with an impressively low detection limit of 0.32 µM. The probe stands out for its exceptional selectivity, minimal susceptibility to interference, and strong adaptability. The probe CCP utilizes the CC bond to trigger a near-infrared fluorescence quenching reaction with HSO3- via nucleophilic addition, which effectively disrupts the large delocalization within the molecule for accurate HSO3- identification. Moreover, the probe has been successfully applied in detecting HSO3- in various food products and living cells, simplifying the measurement of HSO3- content in water samples. This advancement not only enhances the analytical capabilities but also contributes to ensuring food safety and environmental protection. ENVIRONMENTAL IMPLICATION: SO2 derivatives including sulfite/bisulfite, serving dual roles as preservatives and antioxidants, have widespread application across various sectors including food preservation, water sanitation, and the pharmaceutical industry. Despite their widespread application, excessive levels of sulfite/bisulfite can affect human health. Developing methods for precisely and sensitively detecting sulfite/bisulfite in food products and biological samples is important for ensuring food safety and environmental protection. Here, a sensitive near-infrared and multifunctional fluorescent probe in a 99.9 % buffered solution, along with water gel encapsulation, has been successfully applied for the detection of bisulfite in food, authentic water samples, and biological cells.
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Corantes Fluorescentes , Sulfitos , Sulfitos/análise , Sulfitos/química , Corantes Fluorescentes/química , Humanos , Piridinas/química , Carbocianinas/química , Células HeLa , Imagem Óptica , Limite de DetecçãoRESUMO
Schizophrenia is a polygenic complex disease with a heritability as high as 80 %, yet the mechanism of polygenic interaction in its pathogenesis remains unclear. Studying the interaction and regulation of schizophrenia susceptibility genes is crucial for unraveling the pathogenesis of schizophrenia and developing antipsychotic drugs. Therefore, we developed a bioinformatics method named GRACI (Gene Regulation Analysis based on Causal Inference) based on the principles of information theory, a causal inference model, and high order chromatin 3D conformation. GRACI captures the interaction and regulatory relationships between schizophrenia susceptibility genes by analyzing genotyping data. Two datasets, comprising 1459 and 2065 samples respectively, were analyzed, and the gene networks from both datasets were constructed. GRACI showcased superior accuracy when compared to widely adopted methods for detecting gene-gene interactions and intergenic regulation. This alignment was further substantiated by its correlation with chromatin high-order conformation patterns. Using GRACI, we identified three potential genes-KCNN3, KCNH1, and KCND3-that are directly associated with schizophrenia pathogenesis. Furthermore, the results of GRACI on the standalone dataset illustrated the method's applicability to other complex diseases. GRACI download: https://github.com/liuliangjie19/GRACI.
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Cromatina , Biologia Computacional , Predisposição Genética para Doença , Esquizofrenia , Esquizofrenia/genética , Humanos , Cromatina/genética , Redes Reguladoras de Genes , Herança MultifatorialRESUMO
The clinical application of the therapeutic approach in myelodysplastic syndromes (MDS) remains an insurmountable challenge for the high propensity for progressing to acute myeloid leukemia and predominantly affecting elderly individuals. Thus, the discovery of molecular mechanisms underlying the regulatory network of different programmed cell death holds great promise for the identification of therapeutic targets and provides insights into new therapeutic avenues. Herein, we found that disulfiram/copper (DSF/Cu) significantly repressed the cell viability, increased reactive oxygen species (ROS) accumulation, destroyed mitochondrial morphology, and altered oxygen consumption rate. Further studies verified that DSF/Cu induces cuproptosis, as evidenced by the depletion of glutathione (GSH), aggregation of lipoylated DLAT, and induced loss of Fe-S cluster-containing proteins, which could be rescued by tetrathiomolybdate and knockdown of ferredoxin 1 (FDX1). Additionally, GSH contributed to the tolerance of DSF/Cu-mediated cuproptosis, while pharmacological chelation of GSH triggered ROS accumulation and sensitized cell death. The xCT-GSH-GPX4 axis is the ideal downstream component of ferroptosis that exerts a powerful protective mechanism. Notably, classical xCT inhibitors were capable of leading to the catastrophic accumulation of ROS and exerting synergistic cell death, while xCT overexpression restored these phenomena. Simvastatin, an inhibitor of HMG-CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase, has beneficial effects in repurposing for inhibiting GPX4. Similarly, the combination treatment of DSF/Cu and simvastatin dramatically decreased the expression of GPX4 and Fe-S proteins, ultimately accelerating cell death. Moreover, we identified that the combination treatment of DSF/Cu and simvastatin also had a synergistic antitumor effect in the MDS mouse model, with the reduced GPX4, increased COX-2 and accumulated lipid peroxides. Overall, our study provided insight into developing a novel synergistic strategy to sensitize MDS therapy by targeting ferroptosis and cuproptosis.
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Although stem cell therapy holds promise for the treatment of spinal cord injury (SCI), its practical applications are limited by the low degree of neural differentiation. Electrical stimulation is one of the most effective ways to promote the differentiation of stem cells into neurons, but conventional wired electrical stimulation may cause secondary injuries, inflammation, pain, and infection. Here, based on the high conductivity of graphite and the electromagnetic induction effect, graphite nanosheets with neural stem cells (NSCs) are proposed as an electromagnetic cellularized patch to generate in situ wirelessly pulsed electric signals under a rotating magnetic field for regulating neuronal differentiation of NSCs to treat SCI. The strength and frequency of the induced voltage can be controlled by adjusting the rotation speed of the magnetic field. The generated pulsed electrical signals promote the differentiation of NSCs into functional mature neurons and increase the proportion of neurons from 12.5% to 33.7%. When implanted in the subarachnoid region of the injured spinal cord, the electromagnetic cellularized patch improves the behavioral performance of the hind limbs and the repair of spinal cord tissue in SCI mice. This work opens a new avenue for remote treatment of SCI and other nervous system diseases.
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Diferenciação Celular , Células-Tronco Neurais , Traumatismos da Medula Espinal , Animais , Traumatismos da Medula Espinal/terapia , Camundongos , Modelos Animais de Doenças , Neurônios/fisiologia , Grafite/química , Tecnologia sem Fio , Estimulação Elétrica/métodos , Terapia por Estimulação Elétrica/métodosRESUMO
Tumor-associated macrophages within the tumor microenvironment play an immunosuppressive role by promoting tumor growth and immune evasion. Macrophages are highly plastic and can be stimulated to adopt an anti-tumor M1 phenotype. In this study, we used microcystin-LR (MC-LR), a cyclic heptapeptide produced by cyanobacteria, to induce in vitro macrophage innate immunity and transition into the anti-tumor M1 phenotype. MC-LR was also tested in vivo in a mouse model of colorectal cancer. An intraperitoneal injection of MC-LR increased the proportion of CD86⺠M1 macrophages and triggered the maturation of CD11c⺠dendritic cells within tumor tissues. MC-LR combined with the chemotherapeutic drug oxaliplatin significantly inhibited tumor growth in vivo. Flow cytometry analysis revealed increased infiltration of activated cytotoxic (CD8âº, PD-1âº) T-cells and anti-tumor cytokines (IFNγ and Granzyme B) in the tumor tissues of the combination therapy group, suggesting that this may be the primary mechanism behind the anti-tumor effect of the combination treatment. These findings indicate that MC-LR regulates the immune stimulation of macrophage polarization and dendritic cell maturation, effectively reversing tumor immunosuppression, activating an anti-tumor immune response, and enhancing tumor therapy.
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Antineoplásicos , Macrófagos , Oxaliplatina , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Macrófagos/imunologia , Macrófagos/fisiologia , Sinergismo Farmacológico , Animais , Camundongos , Linhagem Celular Tumoral , Neoplasias Retais/tratamento farmacológico , Células Dendríticas , Granzimas/metabolismo , Interferon gama/metabolismo , Imunidade Inata , CianobactériasRESUMO
PURPOSE: Physicians may administer Nirmatrelvir-ritonavir to patients who have been symptomatic for more than 5 days. There is currently no clear evidence to support this approach. METHODS: A real-world study was conducted to investigate the potential relationship between the administration of Nirmatrelvir-ritonavir and the rates of intubation or in-hospital mortality among COVID-19 patients who experienced symptoms for more than 5 days. The end point was a composite event of intubation or in-hospital mortality. The outcomes between those patients who received Nirmatrelvir-ritonavir and those who did not were compared. RESULTS: A total of 847 patients were included in the analysis. Among them, 312 patients (36.84%) received Nirmatrelvir-ritonavir. Within the entire population, 86 patients (10.15%) experienced intubation or in-hospital mortality. The main analysis indicated that there was a significant association between the application of Nirmatrelvir-ritonavir and intubation or in-hospital mortality, with an odds ratio of 0.50 (95% confidence interval, 0.28 to 0.87; P = 0.0153) using inverse probability of treatment weighting. The finding was consistent with multiple sensitivity analyses. CONCLUSIONS: The application of Nirmatrelvir-ritonavir was associated with a significantly reduced risk of intubation or death in hospitalized COVID-19 patients who experienced symptoms for more than 5 days as compared to those who did not receive the treatment.
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Tratamento Farmacológico da COVID-19 , Mortalidade Hospitalar , Ritonavir , Humanos , Ritonavir/uso terapêutico , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , SARS-CoV-2 , Antivirais/uso terapêutico , COVID-19/mortalidade , Hospitalização/estatística & dados numéricos , Resultado do Tratamento , Quimioterapia Combinada , Estudos RetrospectivosRESUMO
Path planning for mobile robots in complex circumstances is still a challenging issue. This work introduces an improved deep reinforcement learning strategy for robot navigation that combines dueling architecture, Prioritized Experience Replay, and shaped Rewards. In a grid world and two Gazebo simulation environments with static and dynamic obstacles, the Dueling Deep Q-Network with Modified Rewards and Prioritized Experience Replay (PMR-Dueling DQN) algorithm is compared against Q-learning, DQN, and DDQN in terms of path optimality, collision avoidance, and learning speed. To encourage the best routes, the shaped Reward function takes into account target direction, obstacle avoidance, and distance. Prioritized replay concentrates training on important events while a dueling architecture separates value and advantage learning. The results show that the PMR-Dueling DQN has greatly increased convergence speed, stability, and overall performance across conditions. In both grid world and Gazebo environments the PMR-Dueling DQN achieved higher cumulative rewards. The combination of deep reinforcement learning with reward design, network architecture, and experience replay enables the PMR-Dueling DQN to surpass traditional approaches for robot path planning in complex environments.
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OBJECTIVES: To observe the clinical efficacy of the spirit-regulation method of Jin's three-needle therapy on post-stroke anxiety and its effects on the hypothalamus-pituitary-adrenal (HPA) axis. METHODS: Fifty-four patients with post-stroke anxiety were divided into spirit regulation (Jin's three needle therapy) group and sham-acupuncture group according to the random number table method, 28 cases in the spirit regulation and 26 cases in the sham-acupuncture group. The patients of the two groups received the same regimen of basic medication and rehabilitation, and the same acupoint prescription was adopted, including Sishenzhen (extra points, 1.5 cun to Baihui ï¼»GV20ï¼½ at 3, 6, 9 and 12 o'clock positions), Shenting (GV24), Yintang (EX-HN3), and bilateral Shenmen (HT7), Sanyinjiao (SP6), Hegu (LI4) and Taichong (LR3). The true acupuncture was delivered in the spirit regulation group and the sham acupuncture operated in the sham-acupuncture group. One treatment lasted for 30 min, once daily, 5 times a week. The duration of treatment was 3 weeks in the trial. Before treatment and on day 10 and day 21 of treatment, the changes in the score of Hamilton anxiety scale (HAMA) and that of National Institutes of Health Stroke Scale (NIHSS) were compared between the two groups separately. Using ELISA, the contents of adrenocorticotropin (ACTH) and cortisol (CORT) in the serum were detected, and the adverse reactions were recorded. RESULTS: In the within-group comparison before and after treatment, HAMA score and NIHSS score dropped on day 10 and day 21 after treatment in the spirit regulation group (P<0.05)ï¼HAMA score and NIHSS score in the sham-acupuncture group were decreased on day 21 of treatment (P<0.05). After 21 days of treatment, HAMA score and NIHSS score in the spirit-regulation group were decreased significantly than those in the sham-acupuncture group (P<0.05) and the contents of ACTH and CORT in the serum decreased when compared with those before treatment and those of the sham-operation group (P<0.05). No obvious adverse events occurred in the spirit-regulation group and the sham-acupuncture group. CONCLUSIONS: Using sham acupuncture as a control, it is preliminarily confirmed that the spirit regulation method of Jin's three-needle therapy is effective on post-stroke anxiety. In association of the downtrend of serological indicators, it is speculated that the underlying mechanism of this therapy is related to HPA axis.
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Terapia por Acupuntura , Acidente Vascular Cerebral , Humanos , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Terapia por Acupuntura/métodos , Ansiedade/terapia , Resultado do Tratamento , Pontos de Acupuntura , Hormônio AdrenocorticotrópicoRESUMO
For the first time the phenomenon of soliton rain is observed in a mode-locked fiber laser with all-polarization-maintaining (all-PM) architecture. The laser is mode-locked using a semiconductor saturable absorber mirror (SESAM) and operates in the all-normal dispersion (ANDi) regime. The operation state of the laser can be switched from dissipative soliton to soliton rain by simply raising the pump power, without any manipulation of the intracavity polarization state given that all components of the resonator are made of PM fibers. The soliton rain generated in the laser is self-starting and replicable, since it occurs in every individual operation of the laser as the pump power is increased to an approximately invariant value.
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Feather, horn, hoof, and other keratin waste are protein-rich but limited by natural keratinase synthesis, activity, pH, and temperature stability. It is challenging to realize its large-scale application in industries. Bacillus subtilis spores are a safe, efficient, and highly resistant immobilized carrier, which can improve target proteins' resistance. In this research, KERQ7, the keratinase gene of Bacillus tequilensis strain Q7, was fused to the Bacillus subtilis genes coding for the coat proteins CotG and CotB, respectively, and displayed on the surface of B. subtilis spores. Compared with the free KERQ7, the immobilized KERQ7 showed a greater pH tolerance and heat resistance on the spore surface. The activity of CotG-KERQ7 is 1.25 times that of CotB-KERQ7, and CotG-KERQ7 is more stable. When the flexible linker peptide L3 was used to connect CotG and KERQ7, the activity was increased to 131.2 ± 3.4%, and the residual enzyme activity was still 62.5 ± 2.2% after being kept at 60 â for 4 h. These findings indicate that the flexible linker and CotG were more effective for the spore surface display of keratinase to improve stress resistance and promote its wide application in feed, tanning, washing, and other industries.
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Proteínas de Bactérias , Esporos Bacterianos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Esporos Bacterianos/genética , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismoRESUMO
Single-cell chromatin accessibility sequencing (scCAS) technologies have enabled characterizing the epigenomic heterogeneity of individual cells. However, the identification of features of scCAS data that are relevant to underlying biological processes remains a significant gap. Here, we introduce a novel method Cofea, to fill this gap. Through comprehensive experiments on 5 simulated and 54 real datasets, Cofea demonstrates its superiority in capturing cellular heterogeneity and facilitating downstream analysis. Applying this method to identification of cell type-specific peaks and candidate enhancers, as well as pathway enrichment analysis and partitioned heritability analysis, we illustrate the potential of Cofea to uncover functional biological process.
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Cromatina , Sequências Reguladoras de Ácido Nucleico , Cromatina/genéticaRESUMO
Acute myocardial infarction (AMI) is a global health threat, and programmed cell death (PCD) plays a crucial role in its occurrence and development. In this study, integrated bioinformatics tools were used to explore new biomarkers and therapeutic targets in AMI. Thirteen types of PCD-related genes were identified through literature review, KEGG, and GSEA pathways. Gene expression matrices and clinical data from AMI patients and healthy controls were obtained from the GEO database. Statistical analysis in R identified 377 differentially expressed genes in AMI patients. Intersection analysis between the differentially expressed genes and PCD-related genes revealed 24 genes positively correlated with immune cells such as Neutrophils and Monocytes, while negatively correlated with T cells CD4 memory resting and Plasma cells. Unsupervised clustering analysis divided patients into two groups (C1 and C2) based on the expression levels of these 24 genes. GSVA analysis showed that C2 patients were more active in pathways related to maintaining normal cell morphology and promoting phagocytosis, suggesting a lower programmed cell death rate and a higher tendency to maintain cell survival. Two hub genes, TNFAIP3 and TP53INP2, were identified through LASSO regression analysis and SVM-RFE, and were validated using an external dataset and RT-qPCRãWestern blot and ELISA analysis. These hub genes showed significantly higher expression and protein secretion levels in AMI patients compared to healthy individuals. Overall, regulating and controlling PCD, particularly through the identified hub genes, TNFAIP3 and TP53INP2, may provide new therapeutic strategies for improving the prognosis of AMI patients and preventing heart failure.
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Apoptose , Infarto do Miocárdio , Humanos , Morte Celular , Sobrevivência Celular , Análise por Conglomerados , Infarto do Miocárdio/genética , Proteínas NuclearesRESUMO
Background: Generalized anxiety disorder (GAD) is common among perimenopausal women. Acupuncture may be an effective treatment for GAD, but evidence is limited. The pathogenesis of GAD is not yet clear, but it is related to the hypothalamic-pituitary-adrenal axis and its excretion, cortisol (CORT), and the adrenocorticotropic hormone (ACTH). The objective of this study is to evaluate the efficacy of manual acupuncture (MA) vs. placebo acupuncture (PA) for perimenopausal women with GAD. Methods: This study is a single-center, randomized, single-blind clinical trial conducted in the First Affiliated Hospital of Guangzhou University of Chinese Medicine. A total of 112 eligible patients with GAD were randomly assigned (1:1) to receive MA (n = 56) or PA (n = 56) three times per week for 4 weeks. The primary outcome measure was the HAMA score. The secondary outcome measures were the GAD-7 and PSQI scores and the levels of CORT and ACTH. The evaluation will be executed at the baseline, 2 weeks, the end of the treatment, and a follow-up 3-month period. Results: Significant improvements in HAMA (p < 0.001, η2p = 0.465), GAD-7 (p < 0.001, η2p = 0.359) and ACTH (p = 0.050) values were found between T0 and T2 in the MA group compared to the PA group. No difference in PSQI (p = 0.613, η2p = 0.011) and CORT (p = 0.903) was found between T0 and T2 in the MA group compared to the PA group. Long-term improvements in HAMA (p < 0.001, p < 0.001) were found in the MA group and PA group. Conclusion: This study was the first completed study to evaluate the efficacy of acupuncture and placebo acupuncture for GAD in perimenopausal patients. Results suggested that placebo acupuncture has a therapeutic effect, however, acupuncture had a greater therapeutic effect than placebo acupuncture. This study supports the effectiveness of acupuncture and thereby contributes to extended treatment options for GAD.Clinical trial registration:http://www.chictr.org.cn, Chinese Clinical Trial Registry, ID: ChiCTR2100046604. Registered on 22 May 2021.
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BACKGROUND: TUB-like protein 4 (TULP4) is one of the distant members of tubby family proteins, whose function remains largely unknown. In the present study, we intend to identify the role of TULP4 in schizophrenia from human samples and animal models. METHODS: Whole-exome sequencing was used to detect the four schizophrenia families collected. In different cell lines, the effects of identified variants in TULP4 gene on its expression and localization were analyzed. Knockdown models in utero and adult mice were employed to investigate the role of Tulp4 on neuronal migration and schizophrenia-related behavior. Subsequently, co-IP assays were used to search for proteins that interact with TULP4 and the effects of mutants on the molecular function of TULP4. RESULTS: For the first time, we identified five rare variants in TULP4 from schizophrenia families, of which three significantly reduced TULP4 protein expression. Knockdown the expression of Tulp4 delayed neuronal migration during embryological development and consequently triggered abnormal behaviors in adult mice, including impaired sensorimotor gating and cognitive dysfunction. Furthermore, we confirmed that TULP4 is involved in the formation of a novel E3 ligase through interaction with CUL5-ELOB/C-RNF7 and the three deleterious variants affected the binding amount of TULP4 and CUL5 to a certain extent. CONCLUSIONS: Together, we believe TULP4 plays an important role in neurodevelopment and subsequent schizophrenic-related phenotypes through its E3 ubiquitin ligase function.
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Oxygen-independent, flavin mononucleotide-based fluorescent proteins (FbFPs) are promising alternatives to green fluorescent protein in anaerobic contexts. Deep mutational scanning performs systematic profiling of protein sequence-function relationships but has not been applied to FbFPs. Focusing on CreiLOV from Chlamydomonas reinhardtii, we created and analyzed two comprehensive mutant collections: (1) single-residue, site-saturation mutagenesis libraries covering all 118 residues; and (2) a full combinatorial metagenesis library among 20 mutations at 15 residues, where mutation and residue selection was based on single-site mutagenesis results. Notably, the second type of library is indispensable to study higher-order epistasis but underrepresented in the literature. Using optimized FACS-seq assays, 2,185 (>92.5%) out of 2,360 possible single-site mutants and 165,428 (>89.7%) out of 184,320 possible combinatorial mutants were reliably assigned with fitness values. We constructed statistical and machine-learning models to analyze the CreiLOV data set, enabling accurate fitness prediction of higher-order mutants using lower-order mutagenesis data. In addition, we successfully isolated CreiLOV variants with improved fluorescence quantum yield and thermostability. This work provides new empirical data and design rules to engineer combinatorial protein variants.