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1.
Cell ; 153(4): 773-84, 2013 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-23663777

RESUMO

5-methylcytosine is a major epigenetic modification that is sometimes called "the fifth nucleotide." However, our knowledge of how offspring inherit the DNA methylome from parents is limited. We generated nine single-base resolution DNA methylomes, including zebrafish gametes and early embryos. The oocyte methylome is significantly hypomethylated compared to sperm. Strikingly, the paternal DNA methylation pattern is maintained throughout early embryogenesis. The maternal DNA methylation pattern is maintained until the 16-cell stage. Then, the oocyte methylome is gradually discarded through cell division and is progressively reprogrammed to a pattern similar to that of the sperm methylome. The passive demethylation rate and the de novo methylation rate are similar in the maternal DNA. By the midblastula stage, the embryo's methylome is virtually identical to the sperm methylome. Moreover, inheritance of the sperm methylome facilitates the epigenetic regulation of embryogenesis. Therefore, besides DNA sequences, sperm DNA methylome is also inherited in zebrafish early embryos.


Assuntos
Metilação de DNA , Embrião não Mamífero/metabolismo , Oócitos/metabolismo , Espermatozoides/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , 5-Metilcitosina/análise , Animais , Epigênese Genética , Feminino , Células Germinativas/metabolismo , Masculino , Peixe-Zebra/metabolismo
2.
Blood ; 142(26): 2305-2314, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-37883798

RESUMO

ABSTRACT: Platelet-activating anti-platelet factor 4 (PF4)/heparin antibodies and anti-PF4 antibodies cause heparin-induced thrombocytopenia (HIT) and vaccine-induced immune thrombocytopenia and thrombosis (VITT), respectively. Diagnostic and treatment considerations differ somewhat between HIT and VITT. We identified patients with thrombocytopenia and thrombosis without proximate heparin exposure or adenovirus-based vaccination who tested strongly positive by PF4/polyanion enzyme-immunoassays and negative/weakly positive by heparin-induced platelet activation (HIPA) test but strongly positive by PF4-induced platelet activation (PIPA) test (ie, VITT-like profile). We tested these patients by a standard chemiluminescence assay that detects anti-PF4/heparin antibodies found in HIT (HemosIL AcuStar HIT-IgG(PF4-H)) as well as a novel chemiluminescence assay for anti-PF4 antibodies found in VITT. Representative control sera included an exploratory anti-PF4 antibody-positive but HIPA-negative/weak cohort obtained before 2020 (n = 188). We identified 9 patients with a clinical-pathological profile of a VITT-like disorder in the absence of proximate heparin or vaccination, with a high frequency of stroke (arterial, n = 3; cerebral venous sinus thrombosis, n = 4), thrombocytopenia (median platelet count nadir, 49 × 109/L), and hypercoagulability (greatly elevated D-dimer levels). VITT-like serological features included strong reactivity by PIPA (aggregation <10 minutes in 9/9 sera) and positive testing in the novel anti-PF4 chemiluminescence assay (3/9 also tested positive in the anti-PF4/heparin chemiluminescence assay). Our exploratory cohort identified 13 additional patient sera obtained before 2020 with VITT-like anti-PF4 antibodies. Platelet-activating VITT-like anti-PF4 antibodies should be considered in patients with thrombocytopenia, thrombosis, and very high D-dimer levels, even without a proximate exposure to heparin or adenovirus vector vaccines.


Assuntos
Anticorpos , Trombocitopenia , Trombose , Trombocitopenia/diagnóstico , Trombocitopenia/patologia , Heparina , Vacinação , Humanos , Fator Plaquetário 4/metabolismo , Anticorpos/análise , Masculino , Feminino , Pré-Escolar , Criança , Adulto , Trombose/diagnóstico , Trombose/patologia
3.
J Neurosci ; 43(15): 2665-2681, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36898835

RESUMO

The Slack channel (KCNT1, Slo2.2) is a sodium-activated and chloride-activated potassium channel that regulates heart rate and maintains the normal excitability of the nervous system. Despite intense interest in the sodium gating mechanism, a comprehensive investigation to identify the sodium-sensitive and chloride-sensitive sites has been missing. In the present study, we identified two potential sodium-binding sites in the C-terminal domain of the rat Slack channel by conducting electrophysical recordings and systematic mutagenesis of cytosolic acidic residues in the rat Slack channel C terminus. In particular, by taking advantage of the M335A mutant, which results in the opening of the Slack channel in the absence of cytosolic sodium, we found that among the 92 screened negatively charged amino acids, E373 mutants could completely remove sodium sensitivity of the Slack channel. In contrast, several other mutants showed dramatic decreases in sodium sensitivity but did not abolish it altogether. Furthermore, molecular dynamics (MD) simulations performed at the hundreds of nanoseconds timescale revealed one or two sodium ions at the E373 position or an acidic pocket composed of several negatively charged residues. Moreover, the MD simulations predicted possible chloride interaction sites. By screening predicted positively charged residues, we identified R379 as a chloride interaction site. Thus, we conclude that the E373 site and the D863/E865 pocket are two potential sodium-sensitive sites, while R379 is a chloride interaction site in the Slack channel.SIGNIFICANCE STATEMENT The research presented here identified two distinct sodium and one chloride interaction sites located in the intracellular C-terminal domain of the Slack (Slo2.2, KCNT1) channel. Identification of the sites responsible for the sodium and chloride activation of the Slack channel sets its gating property apart from other potassium channels in the BK channel family. This finding sets the stage for future functional and pharmacological studies of this channel.


Assuntos
Canais de Potássio Ativados por Sódio , Animais , Ratos , Cloretos/metabolismo , Canais de Potássio Ativados por Sódio/metabolismo , Sódio/metabolismo
4.
J Hepatol ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604387

RESUMO

BACKGROUND & AIMS: In individuals highly exposed to HCV, reinfection is common, suggesting that natural development of sterilising immunity is difficult. In those that are reinfected, some will develop a persistent infection, while a small proportion repeatedly clear the virus, suggesting natural protection is possible. The aim of this study was to characterise immune responses associated with rapid natural clearance of HCV reinfection. METHODS: Broad neutralising antibodies (nAbs) and Envelope 2 (E2)-specific memory B cell (MBC) responses were examined longitudinally in 15 individuals with varied reinfection outcomes. RESULTS: Broad nAb responses were associated with MBC recall, but not with clearance of reinfection. Strong evidence of antigen imprinting was found, and the B-cell receptor repertoire showed a high level of clonality with ongoing somatic hypermutation of many clones over subsequent reinfection events. Single-cell transcriptomic analyses showed that cleared reinfections featured an activated transcriptomic profile in HCV-specific B cells that rapidly expanded upon reinfection. CONCLUSIONS: MBC quality, but not necessarily breadth of nAb responses, is important for protection against antigenically diverse variants, which is encouraging for HCV vaccine development. IMPACT AND IMPLICATIONS: HCV continues to have a major health burden globally. Limitations in the health infrastructure for diagnosis and treatment, as well as high rates of reinfection, indicate that a vaccine that can protect against chronic HCV infection will greatly complement current efforts to eliminate HCV-related disease. With alternative approaches to testing vaccines, such as controlled human inoculation trials under consideration, we desperately need to identify the correlates of immune protection. In this study, in a small but rare cohort of high-risk injecting drug users who were reinfected multiple times, breadth of neutralisation was not associated with ultimate clearance of the reinfection event. Alternatively, characteristics of the HCV-specific B-cell response associated with B-cell proliferation were. This study indicates that humoral responses are important for protection and suggests that for genetically very diverse viruses, such as HCV, it may be beneficial to look beyond just antibodies as correlates of protection.

5.
Fish Shellfish Immunol ; 146: 109382, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242263

RESUMO

The extensive application of Tetrabromobisphenol A (TBBPA) leads to the pollution of part of the water environment and brings great safety risks to aquatic animals. As a natural extract, tea polyphenols (TPs) have antioxidant and anti-inflammatory effects. Gills are one of the immune organs of fish and constitute the first line of defense of the immune system. However, it was unclear whether TPs could mitigate TBBPA-induced gills injury. Therefore, an animal model was established to investigate the effect of TPs on TBBPA-induced gills. The results indicated that TBBPA changed the coefficient and tissue morphology of carp gills. In addition, TBBPA induced oxidative stress and inflammation, leading to ferroptosis and apoptosis in carp gills. Dietary addition of TPs significantly improved the antioxidant capacity of carp, effectively inhibited the overexpression of TLR4/NF-κB and its mediated inflammatory response. Moreover, TPs restored iron metabolism, reduced the expression of pro-apoptotic factors thereby alleviating ferroptosis and apoptosis in carp gills. This study enriched the protective effect of TPs and provided a new way to improve the innate immunity of carp.


Assuntos
Carpas , Ferroptose , Bifenil Polibromatos , Animais , NF-kappa B/genética , NF-kappa B/metabolismo , Antioxidantes/metabolismo , Receptor 4 Toll-Like/genética , Carpas/metabolismo , Brânquias , Polifenóis/farmacologia , Polifenóis/metabolismo , Transdução de Sinais , Proteínas de Peixes , Inflamação/induzido quimicamente , Inflamação/veterinária , Inflamação/metabolismo , Apoptose , Chá/metabolismo
6.
Bioorg Med Chem ; 100: 117631, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38330848

RESUMO

Acute myeloid leukemia (AML) is the most common type of blood cancer and has been strongly correlated with the overexpression of Fms-like tyrosine kinase 3 (FLT3), a member of the class III receptor tyrosine kinase family. With the emergence of FLT3 internal tandem duplication alteration (ITD) and tyrosine kinase domain (TKD) mutations, the development of FLT3 small molecule inhibitors has become an effective medicinal chemistry strategy for AML. Herein, we have designed and synthesized two series of 1H-pyrrolo[2,3-b]pyridine derivatives CM1-CM24, as FLT3 inhibitors based on F14, which we previously reported, that can target the hydrophobic FLT3 back pocket. Among these derivates, CM5 showed significant inhibition of FLT3 and FLT3-ITD, with inhibitory percentages of 57.72 % and 53.77 % respectively at the concentration of 1 µΜ. Furthermore, CM5 demonstrated potent inhibition against FLT3-dependent human AML cell lines MOLM-13 and MV4-11 (both harboring FLT3-ITD mutant), with IC50 values of 0.75 µM and 0.64 µM respectively. In our cellular mechanistic studies, CM5 also effectively induces apoptosis by arresting cell cycle progression in the G0/G1 phase. In addition, the amide and urea linker function were discussed in detail based on computational simulations studies. CM5 will serve as a novel lead compound for further structural modification and development of FLT3 inhibitors specifically targeting AML with FLT3-ITD mutations.


Assuntos
Leucemia Mieloide Aguda , Tirosina Quinase 3 Semelhante a fms , Humanos , Apoptose , Linhagem Celular Tumoral , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Piridinas/farmacologia
7.
J Chem Ecol ; 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372833

RESUMO

The melon fly, Zeugodacus cucurbitae (Coquillett), is a major invasive pest, widely distributed in the Asia-Pacific region and some parts of Africa. Melon fly attractants could improve the effectiveness of current pest management measures. Previous studies have shown that some host fruits are attractive to melon flies but few have investigated the chemical compounds responsible for their attraction. In this study, we aimed to identify the volatile compounds from Luffa acutangula L that attract Z. cucurbitae. In headspace trapping, chemical profiling identified 19 compounds from ridge gourds, with 1-pentadecene being the major component. EAG results revealed that seven compounds elicited antennal responses in Z. cucurbitae, and significant differences in antennal responses between male and female Z. cucurbitae adults were recorded to p-xylene, alpha-pinene, and 1-octadecene. Behavioral experiments demonstrated that the EAG-active compounds methyl isovalerate and methyl myristate had either attractive or repellent effects on Z. cucurbitae at different concentrations, and 1-octadecene attracted Z. cucurbitae. Our findings provide a theoretical basis producing repellents or attractants for effective Integrated Pest Management of Z. cucurbitae.

8.
Acta Pharmacol Sin ; 45(7): 1520-1529, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38519646

RESUMO

Parkin (PARK2) deficiency is frequently observed in various cancers and potentially promotes tumor progression. Here, we showed that Parkin expression is downregulated in liver cancer tissues, which correlates with poor patient survival. Parkin deficiency in liver cancer cells promotes migration and metastasis as well as changes in EMT and metastasis markers. A negative correlation exists between TMEFF1 and Parkin expression in liver cancer cells and tumor tissues. Parkin deficiency leads to upregulation of TMEFF1 which promotes migration and metastasis. TMEFF1 transcription is activated by Parkin-induced endogenous TGF-ß production and subsequent phosphorylation of Smad2/3 and its binding to TMEFF1 promotor. TGF-ß inhibitor and TMEFF1 knockdown can reverse shParkin-induced cell migration and changes of EMT markers. Parkin interacts with and promotes the ubiquitin-dependent degradation of HIF-1α/HIF-1ß and p53, which accounts for the suppression of TGF-ß production. Our data have revealed that Parkin deficiency in cancer leads to the activation of the TGF-ß/Smad2/3 pathway, resulting in the expression of TMEFF1 which promotes cell migration, EMT, and metastasis in liver cancer cells.


Assuntos
Movimento Celular , Neoplasias Hepáticas , Proteína Smad2 , Proteína Smad3 , Fator de Crescimento Transformador beta , Ubiquitina-Proteína Ligases , Humanos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais , Ativação Transcricional , Animais , Transição Epitelial-Mesenquimal , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Metástase Neoplásica , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/genética , Camundongos Nus , Camundongos
9.
Child Dev ; 95(2): e110-e121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37787120

RESUMO

This cross-sectional study explored the relationship between 24-hour movement behaviors and executive function (EF) in preschool children. A total of 426 Han Chinese preschoolers (231 males; 3.8 ± 0.6 years old) from Zhuhai, Guangdong Province, China were selected from October 2021 to December 2021. Accelerometers were used to measure physical activity (PA) and sedentary behavior (SB), while sleep duration was obtained via a parent-report questionnaire. Components of EF (cognitive flexibility, inhibitory control, and working memory) were assessed using computerized behavioral tasks. The daily composition was significantly associated with inhibitory control and working memory. Inhibitory control improvements were linked to the addition of moderate-to-vigorous physical activity (MVPA) at the expense of SB and sleep. The reallocation between MVPA, SB, sleep, and light physical activity yielded a significant association with working memory.


Assuntos
Função Executiva , Exercício Físico , Masculino , Pré-Escolar , Humanos , Estudos Transversais , Sono , Comportamento Sedentário
10.
J Public Health (Oxf) ; 46(1): 107-115, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38264954

RESUMO

BACKGROUND: This study examined the moderating role of outdoor time on the relationship between overweight and myopia. METHODS: The data for this study was obtained from a prospective study in Shanghai, where non-myopic children wore wristwear and were followed up for 1 year. Eye examinations were performed at each visit. The modification effect was assessed on the additive scale using multivariable logistic regression, and relative excess risk due to interaction was used to calculate the modification effect. RESULTS: A total of 4683 non-myopic children were included with 32.20% being overweight at baseline. Following a 1-year period, 17.42% of children had myopia. When compared to those who spent <90 minutes outdoors, children who spent >120 had a relative risk of myopia onset that was reduced to 0.61. As time spent outdoors decreased, more risks of myopia onset were identified among overweight children than among normal children, the modification effect on the additive scale was -0.007, with ~70% of this effect attributed to the modifying influence of outdoor time. CONCLUSIONS: Increasing outdoor time can reduce myopia more among overweight children than normal. Future interventions should focus on outdoor activities among overweight children to reduce myopia risks.


Assuntos
Miopia , Obesidade Infantil , Criança , Humanos , Pré-Escolar , Seguimentos , Estudos Prospectivos , Sobrepeso/complicações , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Obesidade Infantil/etiologia , Atividades de Lazer , China/epidemiologia , Miopia/epidemiologia , Miopia/etiologia , Inquéritos e Questionários
11.
Plant Dis ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956958

RESUMO

Fusarium rot on melon fruit has become an important postharvest disease for producers worldwide, typically involving multiple Fusarium pathogens (Khuna et al. 2022; Medeiros Araújo et al. 2021). In 2022, Fusarium fruit rot of muskmelon (Cucumis melo var. conomon) occurred sporadically in a field at Huainan Academy of Agricultural Sciences (32.658193º N, 117.064922º E) with an incidence of about 10%. Among these diseased muskmelons, a fruit exhibiting a white to yellowish colony athe intersection of the diseased and healthy tissues was collected and labeled TGGF22-17. The streak plate method was employed to isolate fungal spores on Bengal Red PDA (potato dextrose agar), which were then incubated at 25℃ in darkness. Following isolation and purification, a single-spore strain, TGGF22-17, was obtained and analyzed using morphological characters on PDA, synthetic nutrient agar (SNA) and carnation leaf agar (CLA) (Leslie and Summerell 2006), along with molecular identification. Colours were rated according to the color charts of Kornerup and Wanscher (1978). Based on the colony morphology on PDA, the isolate displayed a rosy buff or buff color with a white to buff margin. The colony margin was undulate, with the reverse transitioning from amber-yellow to honey-yellow. Aerial macroconidia on SNA were thin-walled, hyaline, mostly 3-5 septate, falcate, and measured 18.5-46.4 (x̄=34.2) × 2.9-4.8 (x̄ =3.9) µm in size (n =50). Sporodochial macroconidia on CLA were mostly five-septate with long apical and basal cells, exhibiting dorsiventral curvature. They were hyaline, with the apical cell hooked to tapering and the basal cell foot-shaped, measuring 46.5-89.6 (x̄ =72.3) × 3.5-5.0 (x̄ =4.3) µm in size (n = 100). Portions of three loci (TEF-1α, RPB1 and RPB2) were amplified and sequenced as described by Wang et al. (2019). Sequences were deposited in GenBank with accession number PP196583 to PP196585. The three gene sequences (TEF-1α, RPB1 and RPB2) of strain TGGF2022-17 shared 99.5% (629/632bp), 97.9% (1508/1540 bp) and 99.9% (1608/1609 bp) identity to the ex-type strain F. ipomoeae LC12165 respectively by pairwise DNA alignments on the FUSARIOID-ID database (https://www.fusarium.org). Phylogenetic analysis of the partial TEF-1α and RPB2 sequences with PhyloSuite (Zhang et al. 2020) showed the isolated fungus clustered with F. ipomoeae. Based on the morphological and phylogenetic analyses, TGGF22-17 was identified as F. ipomoeae. Pathogenicity tests were performed on healthy melons, which were surface-sterilized with 75% alcohol and wounded using a sterilized inoculation needle. A 4-mm diameter plug from a 7-day-old SNA culture of TGGF22-17 was aseptically inserted in the middle of the wound, sealed with plastic bag after absorbent cotton was included to maintain moisture. Five melons were each inoculated at three points. Noncolonized PDA agar plugs served as the negative control. The inoculated and uninoculated plugs were removed approximately 48 hours after inoculation. The melon inoculated with TGGF22-17 exhibited water-soaked black lesions 48h post-inoculation, resulting in a 100% infection rate (15/15). After 7 days, mycelium was obseved on the inoculated melons. No disease symptoms were observed on the uninoculated melons. To fulfill Koch's postulates, fungi were isolated from the inoculated fruit and confirmed as F. ipomoeae by morphological observation. Fusarium ipomoeae has been reported to cause fruit rot on winter squash (Cucurbita maxima) in Japan (Kitabayashi et al. 2023). To our knowledge, this is the first report of fruit rot on muskmelon caused by F. ipomoeae in China and this report will be valuable for monitoring and management of fruit rot disease on muskmelons.

12.
Chem Soc Rev ; 52(16): 5516-5540, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37482807

RESUMO

Lead halide perovskite nanocrystals are promising for next-generation high-definition displays, especially in light of their tunable bandgaps, high color purities, and high carrier mobility. Within the past few years, the external quantum efficiency of perovskite nanocrystal-based light-emitting diodes has progressed rapidly, reaching the standard for commercial applications. However, the low operational stability of these perovskite nanocrystal-based light-emitting diodes remains a crucial issue for their industrial development. Recent experimental evidence indicates that the migration of ionic species is the primary factor giving rise to the performance degradation of perovskite nanocrystal-based light-emitting diodes, and ion migration is closely related to the defects on the surface of perovskite nanocrystals and at the grain boundaries of their thin films. In this review, we focus on the central idea of surface reconstruction of perovskite nanocrystals, discuss the influence of surface defects on halide ion migration, and summarize recent advances in resurfacing perovskite nanocrystal strategies toward mitigating halide ion migration to improve the stability of the as-fabricated light-emitting diode devices. From the perspective of perovskite nanocrystal resurfacing, we set out a promising research direction for improving both the spectral and operational stability of perovskite nanocrystal-based light-emitting diodes.

13.
J Allergy Clin Immunol ; 152(1): 290-301.e7, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36965845

RESUMO

BACKGROUND: Predominantly antibody deficiency (PAD) is the most common category of inborn errors of immunity and is underpinned by impaired generation of appropriate antibody diversity and quantity. In the clinic, responses are interrogated by assessment of vaccination responses, which is central to many PAD diagnoses. However, the composition of the generated antibody repertoire is concealed from traditional quantitative measures of serological responses. Leveraging modern mass spectrometry-based proteomics (MS-proteomics), it is possible to elaborate the molecular features of specific antibody repertoires, which may address current limitations of diagnostic vaccinology. OBJECTIVES: We sought to evaluate serum antibody responses in patients with PAD following vaccination with a neo-antigen (severe acute respiratory syndrome coronavirus-2 vaccination) using MS-proteomics. METHODS: Following severe acute respiratory syndrome coronavirus-2 vaccination, serological responses in individuals with PAD and healthy controls (HCs) were assessed by anti-S1 subunit ELISA and neutralization assays. Purified anti-S1 subunit IgG and IgM was profiled by MS-proteomics for IGHV subfamily usage and somatic hypermutation analysis. RESULTS: Twelve patients with PAD who were vaccine-responsive were recruited with 11 matched vaccinated HCs. Neutralization and end point anti-S1 titers were lower in PAD. All subjects with PAD demonstrated restricted anti-S1 IgG antibody repertoires, with usage of <5 IGHV subfamilies (median: 3; range 2-4), compared to ≥5 for the 11 HC subjects (P < .001). IGHV3-7 utilization was far less common in patients with PAD than in HCs (2 of 12 vs 10 of 11; P = .001). Amino acid substitutions due to somatic hypermutation per subfamily did not differ between groups. Anti-S1 IgM was present in 64% and 50% of HC and PAD cohorts, respectively, and did not differ significantly between HCs and patients with PAD. CONCLUSIONS: This study demonstrates the breadth of anti-S1 antibodies elicited by vaccination at the proteome level and identifies stereotypical restriction of IGHV utilization in the IgG repertoire in patients with PAD compared with HC subjects. Despite uniformly pauci-clonal antibody repertoires some patients with PAD generated potent serological responses, highlighting a possible limitation of traditional serological techniques. These findings suggest that IgG repertoire restriction is a key feature of antibody repertoires in PAD.


Assuntos
COVID-19 , Doenças da Imunodeficiência Primária , Humanos , Substituição de Aminoácidos , Bioensaio , Vacinação , Imunoglobulina G , Imunoglobulina M , Anticorpos Antivirais
14.
Nano Lett ; 23(8): 3385-3393, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37052258

RESUMO

Lead halide perovskite nanocrystals (LHP NCs) are regarded as promising emitters for next-generation ultrahigh-definition displays due to their high color purity and wide color gamut. Recently, the external quantum efficiency (EQE) of LHP NC based light-emitting diodes (PNC LEDs) has been rapidly improved to a level required by practical applications. However, the poor operational stability of the device, caused by halide ion migration at the grain boundary of LHP NC thin films, remains a great challenge. Herein, we report a resurfacing strategy via pseudohalogen ions to mitigate detrimental halide ion migration, aiming to stabilize PNC LEDs. We employ a thiocyanate solution processed post-treatment method to efficiently resurface CsPbBr3 NCs and demonstrate that the thiocyanate ions can effectively inhibit bromide ion migration in LHP NC thin films. Owing to thiocyanate resurfacing, we fabricated LEDs with a high EQE of 17.3%, a maximum brightness of 48000 cd m-2, and an excellent operation half-life time.

15.
J Biol Chem ; 298(6): 102017, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35526564

RESUMO

Jumonji domain-containing 3 (JMJD3/KDM6B) is a histone demethylase that plays an important role in regulating development, differentiation, immunity, and tumorigenesis. However, the mechanisms responsible for the epigenetic regulation of inflammation during mastitis remain incompletely understood. Here, we aimed to investigate the role of JMJD3 in the lipopolysaccharide (LPS)-induced mastitis model. GSK-J1, a small molecule inhibitor of JMJD3, was applied to treat LPS-induced mastitis in mice and in mouse mammary epithelial cells in vivo and in vitro. Breast tissues were then collected for histopathology and protein/gene expression examination, and mouse mammary epithelial cells were used to investigate the mechanism of regulation of the inflammatory response. We found that the JMJD3 gene and protein expression were upregulated in injured mammary glands during mastitis. Unexpectedly, we also found JMJD3 inhibition by GSK-J1 significantly alleviated the severity of inflammation in LPS-induced mastitis. These results are in agreement with the finding that GSK-J1 treatment led to the recruitment of histone 3 lysine 27 trimethylation (H3K27me3), an inhibitory chromatin mark, in vitro. Furthermore, mechanistic investigation suggested that GSK-J1 treatment directly interfered with the transcription of inflammatory-related genes by H3K27me3 modification of their promoters. Meanwhile, we also demonstrated that JMJD3 depletion or inhibition by GSK-J1 decreased the expression of toll-like receptor 4 and negated downstream NF-κB proinflammatory signaling and subsequently reduced LPS-stimulated upregulation of Tnfa, Il1b, and Il6. Together, we propose that targeting JMJD3 has therapeutic potential for the treatment of inflammatory diseases.


Assuntos
Inibidores Enzimáticos , Histona Desmetilases com o Domínio Jumonji , Mastite , Animais , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Epigênese Genética , Células Epiteliais , Feminino , Histonas/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Lipopolissacarídeos , Glândulas Mamárias Animais/citologia , Mastite/induzido quimicamente , Mastite/tratamento farmacológico , Camundongos
16.
J Am Chem Soc ; 145(4): 2098-2103, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36656917

RESUMO

The first and asymmetric total synthesis of bufogargarizins A and B, two unusual and highly oxygenated twin steroids with rearranged A/B rings, was achieved. The synthetically challenging [7-5-6-5] tetracyclic ring system of bufogargarizin A was efficiently constructed by the first intramolecular Ru-catalyzed [5 + 2] cycloaddition reaction of a vinyl ether cyclopropane-yne. Notably, the interesting [5-7-6-5] tetracyclic skeleton of bufogargarizin B was diastereoselectively reassembled by unique retro-aldol/transannular aldol cascade reactions from the [7-5-6-5] tetracyclic framework.

17.
Anal Chem ; 95(12): 5256-5266, 2023 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-36917632

RESUMO

Myxobacteria are fascinating prokaryotes featuring a potent capacity for producing a wealth of bioactive molecules with intricate chemical topology as well as intriguing enzymology, and thus it is critical to developing an efficient pipeline for bioprospecting. Herein, we construct the database MyxoDB, the first public compendium solely dedicated to myxobacteria, which enabled us to provide an overview of the structural diversity and taxonomic distribution of known myxobacterial natural products. Moreover, we demonstrated that the cutting-edge NMR-based metabolomics was effective to differentiate the biosynthetic priority of myxobacteria, whereby MyxoDB could greatly streamline the dereplication of multifarious known compounds and accordingly speed up the discovery of new compounds. This led to the rapid identification of a class of linear di-lipopeptides (archangimins) and a rare rearranged sterol (corasterol) that were endowed with unique chemical architectures and/or biosynthetic enzymology. We also showcased that NMR-based metabolomics, MyxoDB, and genomics can also work concertedly to accelerate the targeted discovery of a polyketidic compound pyxipyrrolone C. All in all, this study sets the stage for the discovery of many more novel natural products from underexplored myxobacterial resources.


Assuntos
Produtos Biológicos , Myxococcales , Produtos Biológicos/química , Bioprospecção , Imageamento por Ressonância Magnética , Metabolômica
18.
Environ Sci Technol ; 57(45): 17169-17177, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37859331

RESUMO

Biomass-derived carbonaceous materials with graphene/graphene-like structures (BGS) have attracted tremendous attention in the field of environmental remediation. The introduction of graphene/graphene-like structures into raw biochars can effectively improve their properties, such as electrical conductivity, surface functional groups, and catalytic activity. In 2021, the International Organization for Standardization defined graphene as a "single layer of carbon atoms with each atom bound to three neighbours in a honeycomb structure". Considering this definition, several studies have incorrectly referred to BGS (e.g., biomass-derived few-layer graphene or porous graphene-like nanosheets) as "graphene". The definitions and classifications of BGS and their applications in environmental remediation have not been assessed critically thus far. Comprehensive analysis and sufficient and robust evidence are highly desired to accurately determine the specific structures of BGS. In this perspective, we provide a systematic framework to define and classify the BGS. The state-of-the-art methods currently used to determine the structural properties of BGS are scrutinized. We then discuss the design and fabrication of BGS and how their distinctive features could improve the applicability of biomass-derived carbonaceous materials, particularly in environmental remediation. The environmental applications of these BGS are highlighted, and future research opportunities and needs are identified. The fundamental insights in this perspective provide critical guidance for the further development of BGS for a wide range of environmental applications.


Assuntos
Grafite , Grafite/química , Biomassa , Carbono , Porosidade , Alimentos
19.
BMC Endocr Disord ; 23(1): 48, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36814227

RESUMO

OBJECTIVE: Gestational diabetes mellitus (GDM) is a serious complication in pregnancy. Despite controlling the plasma glucose levels with dietary intervention (GDM-D) or insulin therapy (GDM-I), children born of diabetic mothers suffer more long-term complications from childhood to early adulthood. Placental circulation and nutrient exchange play a vital role in fetal development. Additionally, placental endothelial function is an indicator of vascular health, and plays an important role in maintaining placental circulation for nutrient exchange. This study was conducted to assess changes in fetal endothelial dysfunction in GDM under different interventions during pregnancy. METHODS: The primary human umbilical vein endothelial cells (HUVECs) were obtained from normal pregnant women (n = 11), GDM-D (n = 14), and GDM-I (n = 12) patients. LC-MS/MS was used to identify differentially expressed proteins in primary HUVECs among the three groups, after which Bioinformatics analysis was performed. Glucose uptake, ATP level, apoptosis, and differentially expressed proteins were assessed to investigate changes in energy metabolism. RESULTS: A total of 8174 quantifiable proteins were detected, and 142 differentially expressed proteins were identified after comparing patients with GDM-D/GDM-I and healthy controls. Of the 142, 64 proteins were upregulated while 77 were downregulated. Bioinformatics analysis revealed that the differentially expressed proteins were involved in multiple biological processes and signaling pathways related to cellular processes, biological regulation, and metabolic processes. According to the results from KEGG analysis, there were changes in the PI3K/AKT signaling pathway after comparing the three groups. In addition, there was a decrease in glucose uptake in the GDM-I (P < 0.01) group. In GDM-I, there was a significant decrease in the levels of glucose transporter 1 (GLUT1) and glucose transporter 3 (GLUT3). Moreover, glucose uptake was significantly decreased in GDM-I, although in GDM-D, there was only a decrease in the levels of GLUT1. ATP levels decreased in GDM-I (P < 0.05) and apoptosis occurred in both the GDM-D and GDM-I groups. Compared to the normal controls, the levels of phosphate AKT and phosphate AMPK over total AKT and AMPK were reduced in the GDM-I group. CONCLUSION: In summary, endothelial dysfunction occurred in pregnancies with GDM even though the plasma glucose levels were controlled, and this dysfunction might be related to the degree of glucose tolerance. The energy dysfunction might be related to the regulation of the AKT/AMPK/mTOR signaling pathway.


Assuntos
Diabetes Gestacional , Endotélio , Placenta , Adulto , Feminino , Humanos , Gravidez , Trifosfato de Adenosina/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Glicemia/metabolismo , Cromatografia Líquida , Diabetes Gestacional/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Insulina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Placenta/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espectrometria de Massas em Tandem , Endotélio/fisiopatologia
20.
Acta Pharmacol Sin ; 44(11): 2184-2200, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37328648

RESUMO

Clinically, cardiac dysfunction is a key component of sepsis-induced multi-organ failure. Mitochondria are essential for cardiomyocyte homeostasis, as disruption of mitochondrial dynamics enhances mitophagy and apoptosis. However, therapies targeted to improve mitochondrial function in septic patients have not been explored. Transcriptomic data analysis revealed that the peroxisome proliferator-activated receptor (PPAR) signaling pathway in the heart was the most significantly decreased in the cecal ligation puncture-treated mouse heart model, and PPARα was the most notably decreased among the three PPAR family members. Male Pparafl/fl (wild-type), cardiomyocyte-specific Ppara-deficient (PparaΔCM), and myeloid-specific Ppara-deficient (PparaΔMac) mice were injected intraperitoneally with lipopolysaccharide (LPS) to induce endotoxic cardiac dysfunction. PPARα signaling was decreased in LPS-treated wild-type mouse hearts. To determine the cell type in which PPARα signaling was suppressed, the cell type-specific Ppara-null mice were examined. Cardiomyocyte- but not myeloid-specific Ppara deficiency resulted in exacerbated LPS-induced cardiac dysfunction. Ppara disruption in cardiomyocytes augmented mitochondrial dysfunction, as revealed by damaged mitochondria, lowered ATP contents, decreased mitochondrial complex activities, and increased DRP1/MFN1 protein levels. RNA sequencing results further showed that cardiomyocyte Ppara deficiency potentiated the impairment of fatty acid metabolism in LPS-treated heart tissue. Disruption of mitochondrial dynamics resulted in increased mitophagy and mitochondrial-dependent apoptosis in Ppara△CM mice. Moreover, mitochondrial dysfunction caused an increase of reactive oxygen species, leading to increased IL-6/STAT3/NF-κB signaling. 3-Methyladenine (3-MA, an autophagosome formation inhibitor) alleviated cardiomyocyte Ppara disruption-induced mitochondrial dysfunction and cardiomyopathy. Finally, pre-treatment with the PPARα agonist WY14643 lowered mitochondrial dysfunction-induced cardiomyopathy in hearts from LPS-treated mice. Thus, cardiomyocyte but not myeloid PPARα protects against septic cardiomyopathy by improving fatty acid metabolism and mitochondrial dysfunction, thus highlighting that cardiomyocyte PPARα may be a therapeutic target for the treatment of cardiac disease.


Assuntos
Cardiomiopatias , Cardiopatias , Humanos , Masculino , Camundongos , Animais , Miócitos Cardíacos/metabolismo , PPAR alfa/metabolismo , Lipopolissacarídeos , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/prevenção & controle , Cardiomiopatias/metabolismo , Mitocôndrias/metabolismo , Camundongos Knockout , Modelos Animais de Doenças , Ácidos Graxos/metabolismo
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