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The encapsulation of different guest molecules by their different recognition domains of proteins leads to selective binding, catalysis, and transportation. Synthetic hosts capable of selectively binding different guests in their different cavities to mimic the function of proteins are highly desirable but challenging. Here, we report three ladder-shaped, triple-cavity metallacages prepared by multicomponent coordination-driven self-assembly. Interestingly, the porphyrin-based metallacage is capable of heteroleptic encapsulation of fullerenes (C60 or C70) and coronene using its different cavities, allowing distinct allosteric recognition of coronene upon the addition of C60 or C70. Owing to the different binding affinities of the cavities, the metallacage hosts one C60 molecule in the central cavity and two coronene units in the side cavities, while encapsulating two C70 molecules in the side cavities and one coronene molecule in the central cavity. The rational design of multicavity assemblies that enable heteroleptic encapsulation and allosteric recognition will guide the further design of advanced supramolecular constructs with tunable recognition properties.
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Although catenated cages have been widely constructed due to their unique and elegant topological structures, cyclic catenanes formed by the connection of multiple catenane units have been rarely reported. Herein, based on the orthogonal metal-coordination-driven self-assembly, we prepare a series of heterometallic [2]catenanes and cyclic bis[2]catenanes, whose structures are clearly evidenced by single-crystal X-ray analysis. Owing to the multiple positively charged nature, as well as the potential synergistic effect of the Cu(I) and Pt(II) metal ions, the cyclic bis[2]catenanes display broad-spectrum antibacterial activity. This work not only provides an efficient strategy for the construction of heterometallic [2]catenanes and cyclic bis[2]catenanes but also explores their applications as superior antibacterial agents, which will promote the construction of advanced supramolecular structures for biomedical applications.
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The development of supramolecular hosts which can efficiently encapsulate photosensitizers to improve the photodynamic efficacy holds great promise for cancer therapy. Here, we report two perylene diimide-based metallacages that can form stable host-guest complexes with planar conjugated molecules including polycyclic aromatic hydrocarbons and photosensitizers (hypocrellin A). Such host-guest complexation not only prevents the aggregation of photosensitizers in aqueous environments, but also offers fluorescence resonance energy transfer (FRET) from the metallacage to the photosensitizers to further improve the singlet oxygen generation (ΦΔ = 0.66). The complexes are further assembled with amphiphilic polymers, forming nanoparticles with improved stability for anticancer study. Both in vitro and in vivo studies indicate that the nanoparticles display excellent anticancer activities upon light irradiation, showing great potential for cancer photodynamic therapy. This study provides a straightforward and effective approach for enhancing the photosensitivity of conventional photosensitizers via host-guest complexation-based FRET, which will open a new avenue for host-guest chemistry-based supramolecular theranostics.
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The exploration of novel structures and structural transformation of supramolecular assemblies is of vital importance for their functions and applications. Herein, based on coordination-driven self-assembly, we prepare a neutral truncated tetrahedron and a heteroleptic truncated octahedron, whose structures are unambiguously confirmed by X-ray diffraction analysis. More importantly, the truncated tetrahedron is quantitatively transformed into the truncated octahedron through its fusion with another cationic truncated tetrahedron, as evidenced by fluorescence, mass and NMR spectroscopy. This study not only deepens our understanding of the process of supramolecular fusion but also opens up possibilities for the subsequent preparation of advanced supramolecular assemblies with complex structures and integrated functions.
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ß-Coronaviruses remodel host endomembranes to form double-membrane vesicles (DMVs) as replication organelles (ROs) that provide a shielded microenvironment for viral RNA synthesis in infected cells. DMVs are clustered, but the molecular underpinnings and pathophysiological functions remain unknown. Here, we reveal that host fragile X-related (FXR) family proteins (FXR1/FXR2/FMR1) are required for DMV clustering induced by expression of viral non-structural proteins (Nsps) Nsp3 and Nsp4. Depleting FXRs results in DMV dispersion in the cytoplasm. FXR1/2 and FMR1 are recruited to DMV sites via specific interaction with Nsp3. FXRs form condensates driven by liquid-liquid phase separation, which is required for DMV clustering. FXR1 liquid droplets concentrate Nsp3 and Nsp3-decorated liposomes in vitro. FXR droplets facilitate recruitment of translation machinery for efficient translation surrounding DMVs. In cells depleted of FXRs, SARS-CoV-2 replication is significantly attenuated. Thus, SARS-CoV-2 exploits host FXR proteins to cluster viral DMVs via phase separation for efficient viral replication.
Assuntos
COVID-19 , Proteína do X Frágil da Deficiência Intelectual , Lipossomos , Proteínas de Ligação a RNA , SARS-CoV-2 , Humanos , Proliferação de Células , Análise por Conglomerados , COVID-19/metabolismo , COVID-19/virologia , Citoplasma , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Células HeLa , Lipossomos/metabolismo , Organelas , Proteínas de Ligação a RNA/metabolismo , Proteínas não Estruturais Virais/metabolismoRESUMO
There have been reports of long coronavirus disease (long COVID) and breakthrough infections (BTIs); however, the mechanisms and pathological features of long COVID after Omicron BTIs remain unclear. Assessing long-term effects of COVID-19 and immune recovery after Omicron BTIs is crucial for understanding the disease and managing new-generation vaccines. Here, we followed up mild BA.2 BTI convalescents for six-month with routine blood tests, proteomic analysis and single-cell RNA sequencing (scRNA-seq). We found that major organs exhibited ephemeral dysfunction and recovered to normal in approximately six-month after BA.2 BTI. We also observed durable and potent levels of neutralizing antibodies against major circulating sub-variants, indicating that hybrid humoral immunity stays active. However, platelets may take longer to recover based on proteomic analyses, which also shows coagulation disorder and an imbalance between anti-pathogen immunity and metabolism six-month after BA.2 BTI. The immunity-metabolism imbalance was then confirmed with retrospective analysis of abnormal levels of hormones, low blood glucose level and coagulation profile. The long-term malfunctional coagulation and imbalance in the material metabolism and immunity may contribute to the development of long COVID and act as useful indicator for assessing recovery and the long-term impacts after Omicron sub-variant BTIs.
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Infecções Irruptivas , Síndrome de COVID-19 Pós-Aguda , Humanos , Estudos Prospectivos , Proteômica , Estudos Retrospectivos , Anticorpos Neutralizantes , Anticorpos AntiviraisRESUMO
Investigating the mechanisms by which W135 meningococcal conjugate (PSW135-TT) activates adaptive immune responses in mice can provide a comprehensive understanding of the immune mechanisms of bacterial polysaccharide conjugate vaccines. We compared B-cell and T-cell immune responses immunized with W135 meningococcal capsular polysaccharides (PSW135), tetanus toxoid (TT) and PSW135-TT in mice. The results showed that PSW135-TT could induce higher PSW135-specific and TT-specific IgG antibodies with a significant enhancement after two doses. All serum antibodies immunized with PSW135- TT had strong bactericidal activity, whereas none of the serum antibodies immunized with PSW135 had bactericidal activity. Besides, IgM and IgG antibodies immunized with PSW135-TT after two doses were positively correlated with the titer of bactericidal antibodies. We also found Th cells favored Th2 humoral immune responses in PSW135-TT, PSW135, and TT-immunized mice, especially peripheral blood lymphocytes. Furthermore, PSW135-TT and TT could effectively activate bone marrow derived dendritic cells (BMDCs) and promote BMDCs to highly express major histocompatibility complex â ¡ (MHCâ ¡), CD86 and CD40 molecules in mice, whereas PSW135 couldn't. These data verified the typical characteristics of PSW135-TT and TT as T cell dependent antigen (TD-Ag) and PSW135 as T cell independent antigen (TI-Ag), which will be very helpful for further exploration of the immune mechanism of polysaccharide-protein conjugate vaccines and improvement of the quality of bacterial polysaccharide conjugate vaccines in future.
Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis Sorogrupo W-135 , Animais , Camundongos , Sorogrupo , Toxoide Tetânico , Polissacarídeos Bacterianos , Vacinas Conjugadas , Anticorpos Antibacterianos , Imunidade Celular , Imunoglobulina G , Infecções Meningocócicas/prevenção & controleRESUMO
The Farm Animal Genotype-Tissue Expression (FarmGTEx) project has been established to develop a public resource of genetic regulatory variants in livestock, which is essential for linking genetic polymorphisms to variation in phenotypes, helping fundamental biological discovery and exploitation in animal breeding and human biomedicine. Here we show results from the pilot phase of PigGTEx by processing 5,457 RNA-sequencing and 1,602 whole-genome sequencing samples passing quality control from pigs. We build a pig genotype imputation panel and associate millions of genetic variants with five types of transcriptomic phenotypes in 34 tissues. We evaluate tissue specificity of regulatory effects and elucidate molecular mechanisms of their action using multi-omics data. Leveraging this resource, we decipher regulatory mechanisms underlying 207 pig complex phenotypes and demonstrate the similarity of pigs to humans in gene expression and the genetic regulation behind complex phenotypes, supporting the importance of pigs as a human biomedical model.
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Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Suínos/genética , Animais , Humanos , Genótipo , Fenótipo , Análise de Sequência de RNARESUMO
Abstract Diabetic retinopathy (DR) is a metabolic disorder of the retina and one of the common problems of Type-2 diabetes mellitus (T-2DM) causing visual loss even at teen ages. In this research article, oxidative stress was the main cause due to reactive oxygen species (ROS) generation at hyperglycemic state and become as the focus point of this study to describe (DR) complication onset. The present study was conducted to compare three groups: T-2DM with complication, T-2DM without complication and control group. For this purpose, number of the individuals participating in this study were n=110 as subject along with T-2DM patients with complication n=50, T-2DM patients without complication n=50 and rest n=10 are taken as control/ normoglycemic individuals. T-2DM patients with/without complication have TAG level is lower than normoglycemic/ control. An observed value of (HbA1c%) glycosylated or glycated hemoglobin type A1c concentration of T2DM with complication group was highest (9.63%) amongst the examined groups. T-2DM with complication has lowest SOD activity (660.96 U/gHb) but the malondialdehyde (MDA) level was found to be higher (5.96 µmol/L) amongst studied groups. Lowest plasma TAG, and higher plasma MDA level indicate the presence of oxidative stress in T2D with/without complications. SOD activity was decreased due to the protein glycation and the surplus level of lipid detoxification especially found in T-2DM cases. Good glycemic control counteracts the response of Lipid peroxidation usually occurs in hyperglycemic state.
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Disturbances of the microcirculation and abnormal hemorheological properties are important factors that play an important role in disseminated intravascular coagulation (DIC) and result in organ dysfunction or failure. In the present study, we established an animal model of DIC using intravenous Dextran 500 in rats, and used exogenous normal lymph corresponding to 1/15 of whole blood volume for injection through the left jugular vein. We found that normal lymph could improve the blood pressure and survival time of rats with DIC. The results regarding the mesenteric microcirculation showed that the abnormality of the diameter of mesenteric microvessels and micro-blood flow speed in the DIC+lymph group was significantly less than in the DIC+saline group. Whole blood viscosity, relative viscosity, plasma viscosity, hematocrit (Hct), erythrocyte sedimentation rate (ESR), and electrophoresis time of erythrocytes were significantly increased in the DIC+saline group compared to the control group. The electrophoretic length and migration of erythrocytes from the DIC+saline and DIC+lymph groups were significantly slower than the control group. Blood relative viscosity, Hct, ESR, and electrophoretic time of erythrocytes were significantly increased in the DIC+lymph group compared to the control group. Whole blood viscosity, relative viscosity and reduced viscosity were significantly lower in the DIC+lymph group than in the DIC+saline group, and erythrocyte deformability index was also significantly higher than in the DIC+saline and control groups. These results suggest that exogenous normal lymph could markedly improve the acute microcirculation disturbance and the abnormal hemorheological properties in rats with DIC induced by Dextran 500.