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1.
Immunology ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38934051

ABSTRACT

Maintaining intracellular redox balance is essential for the survival, antibody secretion, and mucosal immune homeostasis of immunoglobulin A (IgA) antibody-secreting cells (ASCs). However, the relationship between mitochondrial metabolic enzymes and the redox balance in ASCs has yet to be comprehensively studied. Our study unveils the pivotal role of mitochondrial enzyme PCK2 in regulating ASCs' redox balance and intestinal homeostasis. We discover that PCK2 loss, whether globally or in B cells, exacerbates dextran sodium sulphate (DSS)-induced colitis due to increased IgA ASC cell death and diminished antibody production. Mechanistically, the absence of PCK2 diverts glutamine into the TCA cycle, leading to heightened TCA flux and excessive mitochondrial reactive oxygen species (mtROS) production. In addition, PCK2 loss reduces glutamine availability for glutathione (GSH) synthesis, resulting in a decrease of total glutathione level. The elevated mtROS and reduced GSH expose ASCs to overwhelming oxidative stress, culminating in cell apoptosis. Crucially, we found that the mitochondria-targeted antioxidant Mitoquinone (Mito-Q) can mitigate the detrimental effects of PCK2 deficiency in IgA ASCs, thereby alleviating colitis in mice. Our findings highlight PCK2 as a key player in IgA ASC survival and provide a potential new target for colitis treatment.

2.
J Org Chem ; 89(9): 6416-6427, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38616352

ABSTRACT

A novel conversion of 1,5-diynols into sulfonylated benzo[b]fluorenes is reported by a TFA-promoted cascade cyclization with sodium sulfinates under mild conditions. This strategy provides an efficient and practical approach for accessing various sulfonated benzo[b]fluorenes in moderate to excellent yields under metal-free conditions. On the basis of the control experimental results and density functional theory calculations, a possible cascade transformation mechanism consisting of the dehydration of propargylic alcohols, sulfonylation, allenylation, and Schmittel-type cyclization is proposed. It is worth noting that TFA played an important role in this cascade cyclization, which promoted C-SO2R bond cleavage in a propargylic sulfone intermediate to form allenyl sulfones, followed by Schmittel-type cyclization to give the target product.

3.
Antonie Van Leeuwenhoek ; 117(1): 112, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39133351

ABSTRACT

A Gram-stain-negative, light khaki, strictly aerobic, rod-shaped, motile via multiple flagella, and catalase- and oxidase-positive bacterium, designated as SSM4.3T, was isolated from the seaweed of Gouqi Island in the East China Sea. The novel isolate grows at 0-5.0% NaCl concentrations (w/v) (optimum 1%), pH 5.0-9.0 (optimum pH 7.0), and 15-37 °C (optimum 30 °C). The 16S rRNA gene sequences-based phylogeny indicates that the novel marine isolate belongs to the family Rhizobiaceae and that it shared the greatest sequence similarity (98.9%) with Peteryoungia rhizophila CGMCC 1.15691T. This classification was also supported by phylogenetic analysis using core genes. The predominant fatty acids (≥ 10%) of the strain were identified as C18:1 ω7c/C18:1 ω6c. Q-10 was identified as the major isoprenoid quinone, with trace levels of Q-9 present. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The complete genome size of strain SSM4.3T is 4.39 Mb with a DNA G+C content of 61.3%. The average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values between the genomes of strain SSM4.3T and its closely related representatives were 74.80-86.93%, 20.00-32.30%, and 70.30-91.52%, respectively. Phylogenetic analysis, grounded on the core genes, reveals the evolutionary relationship between SSM4.3T and other Peteryoungia strains. Pan-genomics analysis of 8 previously classified Peteryoungia species and SSM4.3T revealed their unique genetic features and functions. Overall, strain SSM4.3T was considered to be a new species of the Peteryoungia genus; the name Peteryoungia algae sp. nov. has been proposed, with type strain SSM4.3T (= LMG 32561 = MCCC 1K07170).


Subject(s)
Base Composition , DNA, Bacterial , Fatty Acids , Phylogeny , RNA, Ribosomal, 16S , Seaweed , China , RNA, Ribosomal, 16S/genetics , Seaweed/microbiology , DNA, Bacterial/genetics , Fatty Acids/analysis , Fatty Acids/chemistry , Bacterial Typing Techniques , Genome, Bacterial , Sequence Analysis, DNA , Islands , Nucleic Acid Hybridization
4.
Curr Microbiol ; 81(9): 283, 2024 Jul 27.
Article in English | MEDLINE | ID: mdl-39066927

ABSTRACT

A novel bacterium designated as SSA5.23T was isolated from seawater. Cells of SSA5.23T are Gram-stain-negative, short, rod-shaped, and exhibit motility via numerous peritrichous flagella. The strain could grow at temperatures ranging from 15 to 35 °C (optimum at 25 °C), in a salinity range of 0-5.0% (w/v) NaCl, and within a pH range of 6.0-9.0 (optimum at pH 7.0). The predominant cellular fatty acid of SSA5.23T was C18:1 ω7c/C18:1 ω6c, and the major respiratory quinones were Q-9 and Q-10. Diphosphatidylglycerol, phosphatidylethanolamine, and phosphatidylglycerol were identified as the primary polar lipids. The complete genome (5.47 Mb) of SSA5.23T comprises of a circular chromosome of 3.64 Mb and three plasmids, specifically sized at 59.73 kb, 227.82 kb, and 1.54 Mb, respectively. Certain genes located on the plasmids play roles in denitrification, oxidative stress resistance, and osmotic tolerance, which likely contribute to the adaptability of this strain in marine conditions. Core-proteome average amino acid identity analysis effectively identified the strain's affiliation with the genus Affinirhizobium, showing the highest value (89.9%) with Affinirhizobium pseudoryzae DSM 19479T. This classification was further supported by the phylogenetic analysis of concatenated alignment of 170 single-copy orthologous proteins. When compared to related reference strains, SSA5.23T displayed an average nucleotide identity ranging from 74.9 to 80.3% and digital DNA-DNA hybridization values ranging from 19.9 to 23.9%. Our findings confirmed that strain SSA5.23T represents a novel species of the genus Affinirhizobium, for which the name Affinirhizobium gouqiense sp. nov. (type strain SSA5.23T = LMG 32560T = MCCC 1K07165T) was suggested.


Subject(s)
DNA, Bacterial , Fatty Acids , Genome, Bacterial , Phylogeny , Seawater , Seawater/microbiology , China , Fatty Acids/analysis , DNA, Bacterial/genetics , Rhizobium/genetics , Rhizobium/classification , Rhizobium/isolation & purification , Base Composition , Bacterial Typing Techniques , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Islands , Genomics
5.
BMC Pediatr ; 24(1): 352, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38778342

ABSTRACT

BACKGROUND: Galactosemia is an autosomal recessive disorder resulting from an enzyme defect in the galactose metabolic pathway. The most severe manifestation of classic galactosemia is caused by galactose-1-phosphate uridylyltransferase (GALT) deficiency, and this condition can be fatal during infancy if left untreated. It also may result in long-term complications in affected individuals. CASE PRESENTATION: This report describes a patient whose initial clinical symptoms were jaundice and liver dysfunction. The patient's liver and coagulation functions did not improve after multiple admissions and treatment with antibiotics, hepatoprotective and choleretic agents and blood transfusion. Genetic analysis revealed the presence of two variants in the GALT gene in the compound heterozygous state: c.377 + 2dup and c.368G > C (p.Arg123Pro). Currently, the variant locus (c.377 + 2dup) in the GALT gene has not been reported in the Human Gene Mutation Database (HGMD), while c.368G > C (p.Arg123Pro) has not been reported in the Genome Aggregation Database (GnomAD) nor the HGMD in East Asian population. We postulated that the two variants may contribute to the development of classical galactosemia. CONCLUSIONS: Applications of whole-exome sequencing to detect the two variants can improve the detection and early diagnosis of classical galactosemia and, more specifically, may identify individuals who are compound heterozygous with variants in the GALT gene. Variants in the GALT gene have a potential therapeutic significance for classical galactosemia.


Subject(s)
Galactosemias , UTP-Hexose-1-Phosphate Uridylyltransferase , Humans , Galactosemias/genetics , Galactosemias/diagnosis , UTP-Hexose-1-Phosphate Uridylyltransferase/genetics , Male , Female , Mutation , Infant
6.
J Asian Nat Prod Res ; : 1-14, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38958645

ABSTRACT

Breast cancer is the most common malignant tumor and a major cause of mortality among women worldwide. Atramacronoid A (AM-A) is a unique natural sesquiterpene lactone isolated from the rhizome of Atractylodes macrocephala Koidz (known as Baizhu in Chinese). Our study demonstrated that AM-A triggers a specific form of cell death resembling PANoptosis-like cell death. Further analysis indicated that AM-A-induced PANoptosis-like cell death is associated with the CASP-3/PARP-GSDMD-MLKL pathways, which are mediated by mitochondrial dysfunction. These results suggest the potential of AM-A as a lead compound and offer insights for the development of therapeutic agents for breast cancer from natural products.

7.
J Asian Nat Prod Res ; 26(1): 26-37, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38196236

ABSTRACT

Eight new caffeoyl derivatives, elephantomentosides A-H (1 - 8), together with ten known ones (9 - 18), were isolated from the whole plant of Elephantopos tomentosus L. Their structures were elucidated using detailed spectroscopic analysis. Structurally, compounds 1 - 8 are composed of ß-D-glucopyranose, and almost all of the substituent positions are at the C-1' and C-4' of glucopyranose. The anti-inflammatory and antioxidant activities of all isolated compounds were evaluated in vitro. Compounds 9-10, 13-15, and 17-18 exhibited significant DPPH scavenging capacity with IC50 values in the range of 10.01-25.07 µM, in comparison with Vc (IC50, 17.98 µM).


Subject(s)
Antioxidants , Asteraceae , Molecular Structure , Antioxidants/pharmacology , Antioxidants/chemistry , Asteraceae/chemistry , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistry
8.
Anal Bioanal Chem ; 415(23): 5605-5617, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37470813

ABSTRACT

Mayaro virus (MAYV) is an emerging mosquito-borne alphavirus that causes clinical symptoms similar to those caused by Chikungunya virus (CHIKV), Dengue virus (DENV), and Zika virus (ZIKV). To differentiate MAYV from these viruses diagnostically, we have developed a portable device that integrates sample preparation with real-time, reverse-transcription, loop-mediated isothermal amplification (rRT-LAMP). First, we designed a rRT-LAMP assay targeting MAYV's non-structural protein (NS1) gene and determined the limit of detection of at least 10 viral genome equivalents per reaction. The assay was specific for MAYV, without cross-reactions with CHIKV, DENV, or ZIKV. The rRT-LAMP assay was integrated with a sample preparation device (SPD) wherein virus lysis and RNA enrichment/purification were carried out on the spot, without requiring pipetting, while subsequent real-time amplification device (RAD) enables virus detection at the point of care (POC). The functions of our platform were demonstrated using purified MAYV RNA or blood samples containing viable viruses. We have used the devices for detection of MAYV in as short as 13 min, with limit of detection to as low as 10 GEs/reaction.


Subject(s)
Chikungunya virus , Zika Virus Infection , Zika Virus , Animals , Humans , Zika Virus Infection/diagnosis , Zika Virus/genetics , Chikungunya virus/genetics , Nucleic Acid Amplification Techniques , Genome, Viral , RNA, Viral/genetics
9.
Aging Ment Health ; 27(11): 2295-2304, 2023.
Article in English | MEDLINE | ID: mdl-37395111

ABSTRACT

OBJECTIVES: This study aimed to explore the relationship between social isolation and sleep in later life and the role of loneliness in this relationship. METHODS: In Study 1, we conducted a cross-sectional analysis of the correlation between social isolation and sleep in community-dwelling older adults (N = 108). This relationship was assessed using subjective and objective measures. Moreover, we examined the mediating role of loneliness cross-sectionally (Study 1) and longitudinally (Study 2). Longitudinal study was based on three waves of data from the National Scale Life, Health, and Aging Project (N = 1, 554). RESULTS: The results showed that social isolation was robustly associated with sleep in the general population of older adults. Specifically, subjective social isolation was associated with subjective sleep, and objective social isolation was associated with objective sleep. The results of the longitudinal study showed that loneliness mediated the reciprocal link between social isolation and sleep across time after controlling for autoregressive effects and basic demographics. CONCLUSIONS: These findings address the gap in the literature on the link between social isolation and sleep in older adults, extending the understanding of improvement in older adults' social networks, sleep quality, and psychological well-being.


Subject(s)
Loneliness , Social Isolation , Humans , Aged , Cross-Sectional Studies , Longitudinal Studies , Social Isolation/psychology , Loneliness/psychology , Sleep
10.
J Liposome Res ; : 1-10, 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37621197

ABSTRACT

Psoriasis is a chronic, immune-mediated skin disease with no cure. Intravenous arsenic trioxide (ATO) has been used to treat psoriasis in animal studies. However, the high toxicity of ATO limits its application to clinics for systemic administration. The aim of this study was to fabricate sustained-release ATO liposome gels (ATO-Lip-Gels) to be used for the treatment of psoriasis. The ATO Liposomes were prepared using a zinc acetate gradient method. ATO concentrations were analyzed by HPLC-HG-AFS. The ATO-Lip-Gels were characterized with respect to size, zeta potential, and entrapment efficiency. Stability, in vitro drug release, and in vivo efficacy were also evaluated. The optimal formulation of ATO-Lip was ATO (0.45%), S100 (9%), and cholesterol (1.5%) (W/V) in 0.3 mol/L zinc acetate and incubated for 10 min. In the in vitro drug release study, ATO-Lip-Gels exhibited a slower release profile of ATO than that from Gels only. Compared with the model group, ATO-Lip-Gels-H significantly reduced PASI scores after psoriasis in mice and was superior to tacrolimus at day 5. HE staining showed that the pathological changes caused by psoriasis in mice were significantly improved in the treatment groups, and ATO-Lip-Gels-H had the best effect among the treatment groups. ATO-Lip-Gels applied topologically to imiquimote-induced psoriatic plaque models significantly reduced the levels of key psoriatic cytokines such as IL-6 and TNF-α. We have developed ATO-Lip-Gels for the treatment of psoriasis, which demonstrated higher efficacy with the benchmark, Tacrolimus, and can be an alternative to the conventional treatment with Tacrolimus.

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