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1.
Materials (Basel) ; 17(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612160

RESUMO

At the initial rolling temperature of 400 °C, ZK60 magnesium alloy was hot rolled by three different rolling paths with different roll speed ratios (RSR) of 1:1.15, 1:1.2, and 1:1.5, respectively. The effects of different rolling processes on the microstructure and mechanical properties of the alloy were studied. The microstructure, plasticity, strength, hardness, and texture intensity of rolled samples were analyzed in this work. The results show that the microstructure uniformity of the alloy under multi-path asynchronous rolling (MAR) is significantly improved, which improves the mechanical properties of the material to a certain extent, and effectively weakens the texture intensity of the basal plane and reduces the anisotropy. The amount of randomly oriented grains of ZK60 magnesium alloy rolled by the C-1.5 (path C combined with the RSR of 1:1.5) process are significantly increased, which significantly weakens the basal texture and improves the ductility of the alloy, greatly enhancing the processing and formability of ZK60 magnesium alloy.

2.
Bioessays ; 46(4): e2300209, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38488284

RESUMO

The Myelin Regulator Factor (MYRF) is a master regulator governing myelin formation and maintenance in the central nervous system. The conservation of MYRF across metazoans and its broad tissue expression suggest it has functions extending beyond the well-established role in myelination. Loss of MYRF results in developmental lethality in both invertebrates and vertebrates, and MYRF haploinsufficiency in humans causes MYRF-related Cardiac Urogenital Syndrome, underscoring its importance in animal development; however, these mechanisms are largely unexplored. MYRF, an unconventional transcription factor, begins embedded in the membrane and undergoes intramolecular chaperone mediated trimerization, which triggers self-cleavage, allowing its N-terminal segment with an Ig-fold DNA-binding domain to enter the nucleus for transcriptional regulation. Recent research suggests developmental regulation of cleavage, yet the mechanisms remain enigmatic. While some parts of MYRF's structure have been elucidated, others remain obscure, leaving questions about how these motifs are linked to its intricate processing and function.


Assuntos
Bainha de Mielina , Fatores de Transcrição , Animais , Humanos , Fatores de Transcrição/metabolismo , Bainha de Mielina/metabolismo , Proteínas de Membrana/metabolismo , Regulação da Expressão Gênica , Domínios Proteicos
3.
J Phys Chem Lett ; 15(6): 1694-1701, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38316030

RESUMO

Perovskite solar cells (PSCs) have attracted significant attention due to their high efficiencies that are closely associated with the optimized interface of perovskite (PVK) films. However, during film deposition, tremendous interfacial defects are generated in PVK films, which suppress device performance. Herein, we employ an organic molten chloride salt of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) on the PVK surface to regulate the interface properties through surface reconstruction by heating to 110 °C, during which DMTMM undergoes an obvious phase transition from a solid to liquid molten salt. The mobile phase coordinates with unsaturated Pb2+ and halide vacancies to heal the structural defects. After the mixture cools to room temperature, a compact DMTMM interlayer is formed to protect PVKs from degradation in the air. Consequently, the DMTMM-treated MAPbI3-based PSCs yield a champion PCE approaching 20% with optimized stability. This molten-salt-assisted surface reconstruction strategy provides a new approach to establish highly stable hybrid perovskite films for high-performance PSCs.

4.
Thorac Cancer ; 15(9): 681-692, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316627

RESUMO

BACKGROUND: Esophageal cancer (EC), a common and fatal disease, includes two histological subtypes; esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (ECA). To aid policymakers in the allocation of resources for the prevention and treatment of EC, updated data on EC deaths and disability-adjusted life years (DALYs) attributable to high body mass index (BMI) are necessary. The objective of this study was to identify trends in EC associated with high BMI between 1990 and 2019 using 2019 Global Burden of Disease data. METHODS: In this observational population-based study, epidemiological data on the association between high BMI and EC were obtained from GBD 2019. The age-standardized mortality rate (ASMRs) and disability-adjusted life year rate (ASDRs) attributable to high BMI-related EC were stratified by year, age, country, and sociodemographic index (SDI). The estimated annual percentage change (EAPC) was calculated to evaluate the temporal trends of the ASMRs and ASDRs between 1990 and 2019. RESULTS: In 2019, the proportion of EC deaths and DALYs attributed to high BMI was 18.1% and 18.9%, respectively, resulting in 89 904 (95% confidence interval [CI]: 27 879-171 255) deaths and 2 202 314 (95% CI: 681 901-4 173 080) DALYs. High BMI-related deaths and DALYs showed a strong upward trend, increasing by more than two-fold since 1990. East Asia and Western Europe showed the highest risk of EC mortality and DALYs attributable to high BMI; China and the USA bear the greatest burden. The ASMR and ASDR increased in five SDI regions. CONCLUSIONS: The incidence of EC is increasing, particularly in developing nations, which may be attributed to the prevalence of high BMI. To mitigate the impact of high BMI on the incidence of EC, it is important to increase awareness of its deleterious effects, which may alleviate the burden of this disease.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Índice de Massa Corporal , Neoplasias Esofágicas/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida , Carga Global da Doença , Carcinoma de Células Escamosas do Esôfago/epidemiologia
5.
Arab J Gastroenterol ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38423856

RESUMO

We report, for the first time, the safety and effectiveness of antituberculosis drugs after tuberculosis activation during ustekinumab treatment in Crohn's disease.

6.
Adv Mater ; 36(7): e2309428, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37983565

RESUMO

Incredible progress in photovoltaic devices based on hybrid perovskite materials has been made in the past few decades, and a record-certified power conversion efficiency (PCE) of over 26% has been achieved in single-junction perovskite solar cells (PSCs). In the fabrication of high-efficiency PSCs, the postprocessing procedures toward perovskites are essential for designing high-quality perovskite thin films; developing efficient and reliable post-treatment techniques is very important to promote the progress of PSCs. Here, recent post-treatment technological reforms toward perovskite thin films are summarized, and the principal functions of the post-treatment strategies on the design of high-quality perovskite films have been thoroughly analyzed by dividing into two categories in this review: thermal annealing (TA)-related technique and TA-free technique. The latest research progress of the above two types of post-treatment techniques is summarized and discussed, focusing on the optimization of postprocessing conditions, the regulation of perovskite qualities, and the enhancement of device performance. Finally, an outlook of the prospect trends and future challenges for the fabrication of the perovskite layer and the production of highly efficient PSCs is given.

7.
Mol Biol Evol ; 40(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38061001

RESUMO

Parasitoids introduce various virulence factors when parasitism occurs, and some taxa generate teratocytes to manipulate the host immune system and metabolic homeostasis for the survival and development of their progeny. Host-parasitoid interactions are extremely diverse and complex, yet the evolutionary dynamics are still poorly understood. A category of serpin genes, named CvT-serpins, was discovered to be specifically expressed and secreted by the teratocytes of Cotesia vestalis, an endoparasitoid of the diamondback moth Plutella xylostella. Genomic and phylogenetic analysis indicated that the C. vestalis serpin genes are duplicated and most of them are clustered into 1 monophyletic clade. Intense positive selection was detected at the residues around the P1-P1' cleavage sites of the Cv-serpin reactive center loop domain. Functional analyses revealed that, in addition to the conserved function of melanization inhibition (CvT-serpins 1, 16, 18, and 21), CvT-serpins exhibited novel functions, i.e. bacteriostasis (CvT-serpins 3 and 5) and nutrient metabolism regulation (CvT-serpins 8 and 10). When the host-parasitoid system is challenged with foreign bacteria, CvT-serpins act as an immune regulator to reprogram the host immune system through sustained inhibition of host melanization while simultaneously functioning as immune effectors to compensate for this suppression. In addition, we provided evidence that CvT-serpin8 and 10 participate in the regulation of host trehalose and lipid levels by affecting genes involved in these metabolic pathways. These findings illustrate an exquisite tactic by which parasitoids win out in the parasite-host evolutionary arms race by manipulating host immune and nutrition homeostasis via adaptive gene evolution and neofunctionalization.


Assuntos
Mariposas , Parasitos , Serpinas , Vespas , Animais , Serpinas/genética , Filogenia , Mariposas/genética , Homeostase , Larva/metabolismo , Vespas/genética
8.
MedComm (2020) ; 4(6): e397, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37901798

RESUMO

SARS-CoV-2 viruses are highly transmissible and immune evasive. It is critical to develop broad-spectrum prophylactic and therapeutic antibodies for potential future pandemics. Here, we used the phage display method to discover nanobodies (Nbs) for neutralizing SARS-CoV-2 viruses especially Omicron strains. The leading nanobody (Nb), namely, Nb4, with excellent physicochemical properties, can neutralize Delta and Omicron subtypes, including BA.1, BA.1.1 (BA.1 + R346K), BA.2, BA.5, BQ.1, and XBB.1. The crystal structure of Nb4 in complex with the receptor-binding domain (RBD) of BA.1 Spike protein reveals that Nb4 interacts with an epitope on the RBD overlapping with the receptor-binding motif, and thus competes with angiotensin-converting enzyme 2 (ACE2) binding. Nb4 is expected to be effective for neutralizing most recent Omicron variants, since the epitopes are evolutionarily conserved among them. Indeed, trivalent Nb4 interacts with the XBB1.5 Spike protein with low nM affinity and competes for ACE2 binding. Prophylactic and therapeutic experiments in mice indicated that Nb4 could reduce the Omicron virus loads in the lung. In particular, in prophylactic experiments, intranasal administration of multivalent Nb4 completely protected mice from Omicron infection. Taken together, these results demonstrated that Nb4 could serve as a potent and broad-spectrum prophylactic and therapeutic Nb for COVID-19.

9.
Sci Data ; 10(1): 266, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37164995

RESUMO

Microplitis manilae Ashmead (Hymenoptera: Braconidae) is an important parasitoid of agricultural pests in lepidopteran species. So far, two extant genome assembles from the genus Microplitis are fragmented. Here, we offered a high-quality genome assembly of M. manilae at the chromosome level with high accuracy and contiguity, assembled by ONT long-read, MGI-SEQ short-read, and Hi-C sequencing methods. The final assembled genome size was 282.85 Mb, with 268.17 Mb assigned to 11 pseudochromosomes. The scaffold N50 length was 25.23 Mb, and the complete BUSCO score was 98.61%. The genome contained 152.37 Mb of repetitive elements, representing 53.87% of the total genome size. We predicted 15,689 protein-coding genes, of which 13,580 genes were annotated functionally. Gene family evolution investigations of M. manilae revealed 615 expanded and 635 contracted gene families. The high-quality genome of M. manilae reported in this paper will be a useful genomic resource for research on parasitoid wasps in the future.


Assuntos
Genoma de Inseto , Vespas , Animais , Cromossomos , Genômica , Filogenia , Sequências Repetitivas de Ácido Nucleico , Vespas/genética
10.
Math Biosci Eng ; 20(4): 6517-6550, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-37161117

RESUMO

The origin, location and cause of Parkinson's oscillation are not clear at present. In this paper, we establish a new cortex-basal ganglia model to study the origin mechanism of Parkinson beta oscillation. Unlike many previous models, this model includes two direct inhibitory projections from the globus pallidus external (GPe) segment to the cortex. We first obtain the critical calculation formula of Parkinson's oscillation by using the method of Quasilinear analysis. Different from previous studies, the formula obtained in this paper can include the self-feedback connection of GPe. Then, we use the bifurcation analysis method to systematically explain the influence of some key parameters on the oscillation. We find that the bifurcation principle of different cortical nuclei is different. In general, the increase of the discharge capacity of the nuclei will cause oscillation. In some special cases, the sharp reduction of the discharge rate of the nuclei will also cause oscillation. The direction of bifurcation simulation is consistent with the critical condition curve. Finally, we discuss the characteristics of oscillation amplitude. At the beginning of the oscillation, the amplitude is relatively small; with the evolution of oscillation, the amplitude will gradually strengthen. This is consistent with the experimental phenomenon. In most cases, the amplitude of cortical inhibitory nuclei (CIN) is greater than that of cortical excitatory nuclei (CEX), and the two direct inhibitory projections feedback from GPe can significantly reduce the amplitude gap between them. We calculate the main frequency of the oscillation generated in this model, which basically falls between 13 and 30 Hz, belonging to the typical beta frequency band oscillation. Some new results obtained in this paper can help to better understand the origin mechanism of Parkinson's disease and have guiding significance for the development of experiments.


Assuntos
Líquidos Corporais , Doença de Parkinson , Humanos , Globo Pálido , Retroalimentação , Núcleo Celular
11.
Biology (Basel) ; 12(5)2023 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-37237527

RESUMO

Meteorus pulchricornis (Wesmael) is a solitary endoparasitoid of lepidopteran pests and a good candidate for the control of Spodoptera frugiperda. To elucidate the structure of the female reproductive apparatus, which may play a role in facilitating successful parasitism, we presented the description of the morphology and ultrastructure of the whole female reproductive system in a thelytokous strain of M. pulchricornis. Its reproductive system includes a pair of ovaries without specialized ovarian tissues, a branched venom gland, a venom reservoir, and a single Dufour gland. Each ovariole contains follicles and oocytes at different stages of maturation. A fibrous layer, possibly an egg surface protector, coats the surface of mature eggs. The venom gland consists of secretory units (including secretory cells and ducts) with abundant mitochondria, vesicles and end apparatuses in the cytoplasm, and a lumen. The venom reservoir is comprised of a muscular sheath, epidermal cells with few end apparatuses and mitochondria, and a large lumen. Furthermore, venosomes are produced by secretory cells and delivered into the lumen via the ducts. As a result, myriad venosomes are observed in the venom gland filaments and the venom reservoir, suggesting that they may function as a parasitic factor and have important roles in effective parasitism.

12.
ACS Appl Mater Interfaces ; 15(17): 21171-21178, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37083345

RESUMO

The growth of high-quality perovskite films is complicated by the fact of uncontrollable crystallization pathways from perovskite precursors. During solution processing, extensive undesired nonperovskite products including residual solvate intermediates are produced due to quick solvent evaporation, which will adversely affect the efficiency and stability of perovskite solar cells (PSCs). Herein, we developed a highly efficient phase-transition pathway using a polydimethylsiloxane (PDMS)-based facial mask (FM) incubation technique, which enables significant reduction of the perovskite crystallization rate and depression of perovskite aggregation behavior. A surprising finding reveals that this technique induces complete phase transition from solvate intermediates to the perovskite phase, thereby obtaining phase-pure perovskite film. Meanwhile, a high-quality perovskite film with a shiny smooth surface, decreased defect states, and alleviated lattice strain is achieved after utilizing the FM strategy. Consequently, the target-inverted PSCs deliver a respectable efficiency of ∼21% and superior stability in both shelf storage (over 3700 h with 90% of initial efficiency) and light soaking (over 1000 h with 80% of initial efficiency) conditions. Our work highlights the importance of eliminating residual solvate intermediates to construct high-quality perovskites with excellent phase purity for ongoing production of high-performance perovskite-based optoelectronic devices.

13.
Biotechnol Genet Eng Rev ; : 1-17, 2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37032580

RESUMO

To investigate the value of serum eotaxin-2, neutrophil/lymphocyte ratio (NLR), and platelet/lymphocyte ratio (PLR) in the diagnosis and prognosis of colorectal cancer (CRC). The association between different clinicopathological characteristics and eotaxin-2, NLR, and PLR in different patient groups was evaluated. The combined detection indicator and the combined detection's predictive effect on distant metastasis were examined. The receiver operating characteristic (ROC) curve was drawn to evaluate the efficacy of combined detection. The association between eotaxin-2, inflammation markers, and postoperative complications was assessed. Multivariate analysis to investigate the factors affecting the prognosis of patients with CRC. We detected a marked positive correlation between NLR and PLR (p < 0.05, r= 0.209). The AUC of serum eotaxin-2 combined with inflammation markers was 0.889, which was higher than single diagnosis. Compared with the single eotaxin-2 test, the combined detection of eotaxin-2 and inflammation markers might improve the specificity of CRC assessment. In univariate analysis, age, surgical method, high eotaxin-2, and high NLR were associated with postoperative complications. In multivariate analysis, age (≥ 60 years), high eotaxin-2, and high NLR were independent risk elements influencing postoperative complications of CRC. The distant metastasis, TNM staging -Ⅳ stage, NLR ≥ 3.18, and PLR ≥ 193 were independent factors affecting the prognosis of patients with CRC. The combined detection of eotaxin-2 and inflammatory markers has a particular value in improving the diagnosis of CRC, predicting distant metastasis, and guiding the frequency of reexamination after radical resection of CRC.

14.
Nat Commun ; 14(1): 1143, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36854761

RESUMO

The protein phosphatase 2A (PP2A) heterotrimer PP2A-B56α is a human tumour suppressor. However, the molecular mechanisms inhibiting PP2A-B56α in cancer are poorly understood. Here, we report molecular level details and structural mechanisms of PP2A-B56α inhibition by an oncoprotein CIP2A. Upon direct binding to PP2A-B56α trimer, CIP2A displaces the PP2A-A subunit and thereby hijacks both the B56α, and the catalytic PP2Ac subunit to form a CIP2A-B56α-PP2Ac pseudotrimer. Further, CIP2A competes with B56α substrate binding by blocking the LxxIxE-motif substrate binding pocket on B56α. Relevant to oncogenic activity of CIP2A across human cancers, the N-terminal head domain-mediated interaction with B56α stabilizes CIP2A protein. Functionally, CRISPR/Cas9-mediated single amino acid mutagenesis of the head domain blunted MYC expression and MEK phosphorylation, and abrogated triple-negative breast cancer in vivo tumour growth. Collectively, we discover a unique multi-step hijack and mute protein complex regulation mechanism resulting in tumour suppressor PP2A-B56α inhibition. Further, the results unfold a structural determinant for the oncogenic activity of CIP2A, potentially facilitating therapeutic modulation of CIP2A in cancer and other diseases.


Assuntos
Carcinogênese , Proteína Fosfatase 2 , Processamento de Proteína Pós-Traducional , Neoplasias de Mama Triplo Negativas , Humanos , Aminoácidos , Carcinogênese/genética , Carcinogênese/metabolismo , Domínio Catalítico , Fosforilação , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/ultraestrutura , Neoplasias de Mama Triplo Negativas/metabolismo
15.
Virulence ; 14(1): 2171691, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36694288

RESUMO

Polydnaviruses (PDVs), obligatory symbionts with parasitoid wasps, function as host immune suppressors and growth and development regulator. PDVs can induce host haemocyte apoptosis, but the underlying mechanism remains largely unknown. Here, we provided evidence that, during the early stages of parasitism, the activated Cotesia vestalis bracovirus (CvBV) reduced the overall number of host haemocytes by inducing apoptosis. We found that one haemocyte-highly expressed CvBV gene, CvBV-26-4, could induce haemocyte apoptosis. Further analyses showed that CvBV-26-4 has four homologs from other Cotesia bracoviruses and BV from wasps in the genus Glyptapanteles, and all four of them possessed a similar structure containing 3 copies of a well-conserved motif (Gly-Tyr-Pro-Tyr, GYPY). Mass spectrometry analysis revealed that CvBV-26-4 was secreted into plasma by haemocytes and then degraded into peptides that induced the apoptosis of haemocytes. Moreover, ectopic expression of CvBV-26-4 caused fly haemocyte apoptosis and increased the susceptibility of flies to bacteria. Based on this research, a new family of bracovirus genes, Bracovirus apoptosis-inducing proteins (BAPs), was proposed. Furthermore, it was discovered that the development of wasp larvae was affected when the function of CvBV BAP was obstructed in the parasitized hosts. The results of our study indicate that the BAP gene family from the bracoviruses group is crucial for immunosuppression during the early stages of parasitism.


Assuntos
Mariposas , Polydnaviridae , Vespas , Animais , Polydnaviridae/genética , Hemócitos , Larva , Apoptose
16.
Discov Med ; 34(171): 45-58, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36494326

RESUMO

miR-21 is involved in the mechanisms of inflammatory bowel disease (IBD). It negatively regulates PTEN, which is an upstream regulatory gene of the PI3K/Akt/mTOR signaling pathway. But the relationship between miR-21 and immune tolerance and intestinal epithelial injury, and the mechanism by which miR-21 participates in Crohn's disease (CD) have not been studied. We aimed to address these two questions. The results of the present study showed that the levels of miR-21 and PTEN respectively decreased and increased significantly in the intestinal mucosa from active CD compared with control ones. Transfection with miR-21-5p mimics significantly downregulated the expression of PTEN and upregulated PI3K-Akt-mTOR signaling and the downstream pathway in PBMCs, while transfection with a miR-21-5p inhibitor antagomiR-21had the opposite effect. Moreover, the ratio of Treg/Th1 cells differentiated from peripheral blood mononuclear cells (PBMCs) decreased after being transfected with mimics, and increased with the inhibitor. AntagomiR-21 significantly relieved the lesions in colons of mice with TNBS-induced colitis, accompanied by the upregulation of PTEN and downregulation of mTOR. Inhibition of miR-21 also effectively suppressed the process of epithelial-mesenchymal transition (EMT) in vivo. In conclusion, the level of miR-21 decreased in CD, resulting in an upregulated PI3K-Akt-mTOR signaling pathway, compromised immune tolerance, and elevated inflammation.


Assuntos
Doença de Crohn , MicroRNAs , Camundongos , Animais , Transição Epitelial-Mesenquimal/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Doença de Crohn/genética , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais , Tolerância Imunológica
17.
Cogn Neurodyn ; 16(6): 1449-1460, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36408065

RESUMO

Different from many previous theoretical studies, this paper explores the regulatory mechanism of the spike and wave discharges (SWDs) in the reticular thalamic nucleus (TRN) by a dynamic computational model. We observe that the SWDs appears in the TRN by changing the coupling weights and delays in the thalamocortical circuit. The abundant poly-spikes wave discharges is also induced when the delay increases to large enough. These discharges can be inhibited by tuning the inhibitory output from the basal ganglia to the thalamus. The mechanisms of these waves can be explained in this model together with simulation results, which are different from the mechanisms in the cortex. The TRN is an important target in treating epilepsy, and the results may be a theoretical evidence for experimental study in the future.

18.
Ecotoxicol Environ Saf ; 244: 114031, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36087466

RESUMO

Human exposure to microplastics (MPs) continues to occur due to ingestion of contaminated food, water and air. Intake of MPs can pose potential health risks by interfering with the production and circulation of nutrients, leading to physiological stress (such as immune responses and metabolic abnormalities). Toxicity data of MPs based on healthy individuals may not be applicable to large populations of patients with chronic diseases represented by diabetes. Therefore, in this study, the response of diabetic mice was compared with that of healthy mice after exposure to polystyrene microplastics (PS-MPs), and interesting differences were observed. PS-MPs exposure significantly increased liver tissue damage, abnormal lipid metabolism, inflammatory effect, liver metabolic disorder and changes of intestinal microbial composition in diabetic mice. Moreover, PS-MPs overstated abnormal lipid metabolism in diabetic mice. The difference between the increased inflammation after exposure to PS-MPs in healthy and diabetic mice involves that the former is mainly modulated by gut microbes, while diabetic mice seem to be more susceptible to lipid metabolism disturbances. In addition, the size effect of MPs was also observed in diabetic mice. These results suggested that individuals with chronic diseases may be more sensitive to pollution due to altered homeostasis, and therefore disease status should be fully considered when assessing the health risk of pollutants.


Assuntos
Diabetes Mellitus Experimental , Poluentes Ambientais , Poluentes Químicos da Água , Animais , Inflamação/induzido quimicamente , Metabolismo dos Lipídeos , Camundongos , Microplásticos/toxicidade , Plásticos/metabolismo , Poliestirenos/metabolismo , Poliestirenos/toxicidade , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
19.
Front Immunol ; 13: 877027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35663984

RESUMO

Parasitoids are widespread in natural ecosystems and normally equipped with diverse viral factors to defeat host immune responses. On the other hand, parasitoids can enhance the antibacterial abilities and improve the hypoimmunity traits of parasitized hosts that may encounter pathogenic infections. These adaptive strategies guarantee the survival of parasitoid offspring, yet their underlying mechanisms are poorly understood. Here, we focused on Cotesia vestalis, an endoparasitoid of the diamondback moth Plutella xylostella, and found that C. vestalis parasitization decreases the number of host hemocytes, leading to disruption of the encapsulation reaction. We further found that one bracovirus C-type lectin gene, CvBV_28-1, is highly expressed in the hemocytes of parasitized hosts and participates in suppressing the proliferation rate of host hemocytes, which in turn reduces their population and represses the process of encapsulation. Moreover, CvBV_28-1 presents a classical bacterial clearance ability via the agglutination response in a Ca2+-dependent manner in response to gram-positive bacteria. Our study provides insights into the innovative strategy of a parasitoid-derived viral gene that has dual functions to manipulate host immunity for a successful parasitism.


Assuntos
Mariposas , Polydnaviridae , Vespas , Animais , Ecossistema , Imunidade , Lectinas Tipo C , Polydnaviridae/genética , Proteínas Virais/genética
20.
Cell Rep Med ; 3(6): 100660, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35732156

RESUMO

Glucocorticoid-induced tumor necrosis factor receptor (GITR) is a co-stimulatory receptor and an important target for cancer immunotherapy. We herein present a potent FcγR-independent GITR agonist IBI37G5 that can effectively activate effector T cells and synergize with anti-programmed death 1 (PD1) antibody to eradicate established tumors. IBI37G5 depends on both antibody bivalency and GITR homo-dimerization for efficient receptor cross-linking. Functional analyses reveal bell-shaped dose responses due to the unique 2:2 antibody-receptor stoichiometry required for GITR activation. Antibody self-competition is observed after concentration exceeded that of 100% receptor occupancy (RO), which leads to antibody monovalent binding and loss of activity. Retrospective pharmacokinetics/pharmacodynamics analysis demonstrates that the maximal efficacy is achieved at medium doses with drug exposure near saturating GITR occupancy during the dosing cycle. Finally, we propose an alternative dose-finding strategy that does not rely on the traditional maximal tolerated dose (MTD)-based paradigm but instead on utilizing the RO-function relations as biomarker to guide the clinical translation of GITR and similar co-stimulatory agonists.


Assuntos
Glucocorticoides , Receptores de IgG , Linhagem Celular Tumoral , Proteína Relacionada a TNFR Induzida por Glucocorticoide/agonistas , Ligantes , Receptores do Fator de Necrose Tumoral/agonistas , Estudos Retrospectivos , Fatores de Necrose Tumoral
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