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1.
JAMA ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700901

RESUMO

This Medical News article discusses approaches to slow the spread of antimicrobial resistance in Neisseria gonorrhoeae.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124352, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38678841

RESUMO

Mucin 1 is an essential tumor biomarker, and developing cost-effective and portable methods for mucin 1 detection is crucial in resource-limited settings. Herein, the pH-regulated dual-enzyme mimic activities of manganese dioxide nanosheets were demonstrated, which were integrated into an aptasensor for dual-mode detection of mucin 1. Under acidic conditions, manganese dioxide nanosheets with oxidase mimic activities catalyzed the oxidation of 3,3',5,5'-tetramethylbenzidine sulfate, producing visible multicolor signals; while under basic conditions, manganese dioxide nanosheets with catalase mimic activities were used as catalyst for the decomposition of hydrogen peroxide, generating gas pressure signals. The proposed method allows the naked eye detection of mucin 1 through multicolor signal readout and the quantitative detection of mucin 1 with a handheld pressure meter or a UV-vis spectrophotometer. The study demonstrates that manganese dioxide nanosheets with pH-regulated dual-enzyme mimic activities can facilitate multidimensional transducing signals. The use of manganese dioxide nanosheets for the transduction of different signals avoids extra labels and simplifies the operation procedures. Besides, the signal readout mode can be selected according to the available detection instruments. Therefore, the use of manganese dioxide nanosheets with pH-regulated dual-enzyme mimic activities for dual-signal readout provides a new way for mucin 1 detection.


Assuntos
Compostos de Manganês , Mucina-1 , Nanoestruturas , Óxidos , Compostos de Manganês/química , Concentração de Íons de Hidrogênio , Mucina-1/análise , Óxidos/química , Nanoestruturas/química , Humanos , Colorimetria/métodos , Benzidinas/química , Pressão , Técnicas Biossensoriais/métodos , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Aptâmeros de Nucleotídeos/química
3.
PLoS One ; 19(4): e0300423, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38626141

RESUMO

BACKGROUND: Numerous metabolomic studies have confirmed the pivotal role of metabolic abnormalities in the development of idiopathic pulmonary fibrosis (IPF). Nevertheless, there is a lack of evidence on the causal relationship between circulating metabolites and the risk of IPF. METHODS: The potential causality between 486 blood metabolites and IPF was determined through a bidirectional two-sample Mendelian randomization (TSMR) analysis. A genome-wide association study (GWAS) involving 7,824 participants was performed to analyze metabolite data, and a GWAS meta-analysis involving 6,257 IPF cases and 947,616 control European subjects was conducted to analyze IPF data. The TSMR analysis was performed primarily with the inverse variance weighted model, supplemented by weighted mode, MR-Egger regression, and weighted median estimators. A battery of sensitivity analyses was performed, including horizontal pleiotropy assessment, heterogeneity test, Steiger test, and leave-one-out analysis. Furthermore, replication analysis and meta-analysis were conducted with another GWAS dataset of IPF containing 4,125 IPF cases and 20,464 control subjects. Mediation analyses were used to identify the mediating role of confounders in the effect of metabolites on IPF. RESULTS: There were four metabolites associated with the elevated risk of IPF, namely glucose (odds ratio [OR] = 2.49, 95% confidence interval [95%CI] = 1.13-5.49, P = 0.024), urea (OR = 6.24, 95% CI = 1.77-22.02, P = 0.004), guanosine (OR = 1.57, 95%CI = 1.07-2.30, P = 0.021), and ADpSGEGDFXAEGGGVR (OR = 1.70, 95%CI = 1.00-2.88, P = 0.0496). Of note, the effect of guanosine on IPF was found to be mediated by gastroesophageal reflux disease. Reverse Mendelian randomization analysis displayed that IPF might slightly elevate guanosine levels in the blood. CONCLUSION: Conclusively, hyperglycemia may confer a promoting effect on IPF, highlighting that attention should be paid to the relationship between diabetes and IPF, not solely to the diagnosis of diabetes. Additionally, urea, guanosine, and ADpSGEGDFXAEGGGVR also facilitate the development of IPF. This study may provide a reference for analyzing the potential mechanism of IPF and carry implications for the prevention and treatment of IPF.


Assuntos
Diabetes Mellitus , Fibrose Pulmonar Idiopática , Humanos , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Guanosina , Fibrose Pulmonar Idiopática/genética , Ureia
4.
Genome Biol Evol ; 16(4)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38620076

RESUMO

Most traits are polygenic, and the contributing loci can be identified by genome-wide association studies. The genetic basis of adaptation (adaptive architecture) is, however, difficult to characterize. Here, we propose to study the adaptive architecture of traits by monitoring the evolution of their phenotypic variance during adaptation to a new environment in well-defined laboratory conditions. Extensive computer simulations show that the evolution of phenotypic variance in a replicated experimental evolution setting can distinguish between oligogenic and polygenic adaptive architectures. We compared gene expression variance in male Drosophila simulans before and after 100 generations of adaptation to a novel hot environment. The variance change in gene expression was indistinguishable for genes with and without a significant change in mean expression after 100 generations of evolution. We suggest that the majority of adaptive gene expression evolution can be explained by a polygenic architecture. We propose that tracking the evolution of phenotypic variance across generations can provide an approach to characterize the adaptive architecture.


Assuntos
Herança Multifatorial , Fenótipo , Animais , Masculino , Adaptação Fisiológica/genética , Evolução Molecular , Drosophila simulans/genética , Drosophila/genética , Evolução Biológica , Simulação por Computador
5.
Res Sq ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38562821

RESUMO

Given the safety, tumor tropism, and ease of genetic manipulation in non-pathogenic Escherichia coli (E. coli), we designed a novel approach to deliver biologics to overcome poor trafficking and exhaustion of immune cells in the tumor microenvironment, via the surface display of key immune-activating cytokines on the outer membrane of E. coli K-12 DH5α. Bacteria expressing murine decoy-resistant IL18 mutein (DR18) induced robust CD8+ T and NK cell-dependent immune responses leading to dramatic tumor control, extending survival, and curing a significant proportion of immune-competent mice with colorectal carcinoma and melanoma. The engineered bacteria demonstrated tumor tropism, while the abscopal and recall responses suggested epitope spreading and induction of immunologic memory. E. coli K-12 DH5α engineered to display human DR18 potently activated mesothelin-targeting CAR NK cells and safely enhanced their trafficking into the tumors, leading to improved control and survival in xenograft mice bearing mesothelioma tumor cells, otherwise resistant to NK cells. Gene expression analysis of the bacteria-primed CAR NK cells showed enhanced TNFα signaling via NFkB and upregulation of multiple activation markers. Our novel live bacteria-based immunotherapeutic platform safely and effectively induces potent anti-tumor responses in otherwise hard-to-treat solid tumors, motivating further evaluation of this approach in the clinic.

6.
Vaccines (Basel) ; 12(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38675787

RESUMO

The durability of an antibody (Ab) response is highly important for antiviral vaccines. However, due to the complex compositions of natural virions, the molecular determinants of Ab durability from viral infection or inactivated viral vaccines have been incompletely understood. Here we used a reductionist system of liposome-based virus-like structures to examine the durability of Abs from primary immune responses in mice. This system allowed us to independently vary fundamental viral attributes and to do so without additional adjuvants to model natural viruses. We show that a single injection of protein antigens (Ags) orderly displayed on a virion-sized liposome is sufficient to induce a long-lived neutralizing Ab (nAb) response. The introduction of internal nucleic acids dramatically modulates the magnitude of Ab responses without an alteration of the long-term kinetic trends. These Abs are characterized by very slow off-rates of ~0.0005 s-1, which emerged as early as day 5 after injection and these off-rates are comparable to that of affinity-matured monoclonal Abs. A single injection of these structures at doses as low as 100 ng led to lifelong nAb production in mice. Thus, a minimal virus-like immunogen can give rise to potent and long-lasting antiviral Abs in a primary response in mice without live infection. This has important implications for understanding both live viral infection and for optimizing vaccine design.

7.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124310, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38663132

RESUMO

Cytochrome c (Cyt-c) was commonly an intrinsic biomarker for a variety of cellular characteristics, such as respiration, energy levels, and apoptosis. Herein, a simple fluorescence sensor was constructed for the detection of Cyt-c in buffer and real serum samples. The carbon dots doped with Tb3+ on the premise of 1-(2-pyridylazo)-2-naphthol (PAN) were fabricated and used as a dual-emission ratiometric fluorescent probe for detecting Cyt-c based on the internal filtering effect (IFE). As a fluorescent probe for ultra-sensitive detection, Cyt-c was quantitatively detected at different concentrations from 1 to 1000 nM. The fluorescent detection method for Cyt-c showed a good linear relationship from 1 to 50 nM, and the limit of detection (LOD) was 0.35 nM. In the recovery range of 101.27-103.39 % in human serum samples, the relative standard deviation (RSD) was less than 3.27 % (n = 3). In the end, the possible structures of CDs were predicted by DFT theoretical simulation calculations. All the results proved the ability of carbon dots as fluorescent probes to detect biomarkers and the application prospects in bioanalysis.


Assuntos
Carbono , Citocromos c , Corantes Fluorescentes , Limite de Detecção , Pontos Quânticos , Espectrometria de Fluorescência , Térbio , Corantes Fluorescentes/química , Carbono/química , Humanos , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos , Térbio/química , Citocromos c/sangue , Citocromos c/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-38524397

RESUMO

Purpose: Circular RNAs (circRNAs) are newly identified endogenous non-coding RNAs that function as crucial gene modulators in the development of several diseases. By assessing the expression levels of circRNAs in peripheral blood mononuclear cells (PBMCs) from patients with chronic obstructive pulmonary disease (COPD), this study attempted to find new biomarkers for COPD screening. Patients and Methods: We confirmed altered circRNA expression in PBMCs of COPD (n=41) vs controls (n=29). Further analysis focused on the highest and lowest circRNA expression levels. The T-test is used to assess the statistical variances in circRNAs among COPD patients in the smoking and non-smoking cohorts. Additionally, among smokers, the Spearman correlation test assesses the association between circRNAs and clinical indicators. Results: Two circRNAs, hsa_circ_0042590 and hsa_circ_0049875, that were highly upregulated and downregulated in PBMCs from COPD patients were identified and verified. Smokers with COPD had lower hsa_circ_0042590 and higher hsa_circ_0049875, in comparison to non-smokers. There was a significant correlation (r=0.52, P<0.01) between the number of acute exacerbations (AEs) that smokers with COPD experienced in the previous year and the following year (r=0.67, P<0.001). Moreover, hsa_circ_0049875 was connected to the quantity of AEs in the year prior (r=0.68, P<0.0001) as well as the year after (r=0.72, P<0.0001). AUC: 0.79, 95% CI: 0.1210-0.3209, P<0.0001) for hsa_circ_0049875 showed a strong diagnostic value for COPD, according to ROC curve analysis. Hsa_circ_0042590 showed a close second with an AUC of 0.83 and 95% CI: -0.1972--0.0739 (P <0.0001). Conclusion: This research identified a strong correlation between smoking and hsa_circ_0049875 and hsa_circ_0042590 in COPD PBMCs. The number of AEs in the preceding and succeeding years was substantially linked with the existence of hsa_circ_0042590 and hsa_circ_0049875 in COPD patients who smoke. Additionally, according to our research, hsa_circ_0049875 and hsa_circ_0042590 may be valuable biomarkers for COPD diagnosis.


Assuntos
Doença Pulmonar Obstrutiva Crônica , RNA Circular , Humanos , RNA Circular/genética , Leucócitos Mononucleares/metabolismo , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , Biomarcadores/metabolismo
9.
J Ovarian Res ; 17(1): 66, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504307

RESUMO

BACKGROUND: Quiescin sulfhydryl oxidase 2 (QSOX2) is a flavin adenine dinucleotide-dependent sulfhydryl oxidase that is known to be involved in protein folding, cell growth regulation, and redox state modification through oxidative activities. Earlier studies demonstrated the tissue and cellular localization of QSOX2 in the male reproductive tract, as well as the highly-regulated mechanism of QSOX2 protein synthesis and expression through the coordinated action of testosterone and epididymal-enriched amino acid, glutamate. However, the presence and the functions of QSOX2 in female reproduction are unknown. In this study, we applied the Cre-loxP gene manipulation system to generate the heterozygous and homozygous Qsox2 knockout mice and examined its effects on ovarian function. RESULTS: We demonstrated that QSOX2 was detected in the follicle-supporting cells (granulosa and cumulus cells) of ovarian follicles of all stages but was absent in the corpus luteum, suggesting its supportive role in folliculogenesis. In comparison with reproductive organogenesis in wild-type mice, there was no difference in testicular and epididymal structure in male Qsox2 knockout; however, Qsox2 knockout disrupted the regular ovulation process in female mice as a drastic decrease in the formation of the corpus luteum was detected, and no pregnancy was achieved when mating males with homozygous Qsox2 knockout females. RNAseq analyses further revealed that Qsox2 knockout altered critical signaling pathways and genes that are responsible for maintaining ovarian functions. CONCLUSION: Our data demonstrated for the first time that Qsox2 is critical for ovarian function in mice.


Assuntos
Células da Granulosa , Oxirredutases , Tamoxifeno , Feminino , Camundongos , Masculino , Animais , Células da Granulosa/metabolismo , Tamoxifeno/farmacologia , Tamoxifeno/metabolismo , Ovário , Ovulação , Camundongos Knockout
10.
BMC Mol Cell Biol ; 25(1): 10, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38523262

RESUMO

BACKGROUND: OP9 mouse stromal cell line has been widely used to induce differentiation of human embryonic stem cells (hESCs) into hematopoietic stem/progenitor cells (HSPCs). However, the whole co-culture procedure usually needs 14-18 days, including preparing OP9 cells at least 4 days. Therefore, the inefficient differentiation system is not appreciated. We aimed to optimize the culture conditions to improve differentiation efficiency. METHODS: In the experimental group, we set six different densities of OP9 cells and just cultured them for 24 h before co-culture, and in the control group, OP9 cells were cultured for 4 days to reach an overgrown state before co-culture. Then we compared the hematopoietic differentiation efficiency among them. RESULTS: OP9 cells were randomly assigned into two groups. In the experimental group, six different plated numbers of OP9 cells were cultured for 1 day before co-culture with hESCs. In contrast, in the control group, OP9 cells were cultured for 4 days at a total number of 3.1 × 104 cells/cm2 in a 6-well plate to reach an overgrown state before co-culture. Hematopoietic differentiation was evaluated with CD34 immunostaining, and compared between these two groups. We could not influence the differentiation efficiency of OP9 cells with a total number of 10.4 × 104 cells/cm2 in a 6-well plate which was cultured just for 1 day, followed by co-culture with hESCs. It reached the same differentiation efficiency 5 days earlier than the control group. CONCLUSION: The peak of CD34 + cells appeared 2 days earlier compared to the control group. A total number of 1.0 × 106 cells in a 6-well plate for OP9 cells was appropriate to have high differentiation efficiency.


Assuntos
Células-Tronco Hematopoéticas , Células Estromais , Animais , Camundongos , Humanos , Células Estromais/metabolismo , Diferenciação Celular , Técnicas de Cocultura , Células Cultivadas
11.
MycoKeys ; 103: 37-55, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38516363

RESUMO

The Calocybe species possess notable economic and medicinal value, demonstrating substantial potential for resource utilization. The taxonomic studies of Calocybe are lacking in quality and depth. Based on the specimens collected from northeast China, this study provides a detailed description of two newly discovered species, namely Calocybebetulicola and Calocybecystidiosa, as well as two commonly found species, Calocybedecolorata and Calocybeionides. Additionally, a previously unrecorded species, C.decolorata, has recently been discovered in Jilin Province, China. The two newly discovered species can be accurately distinguished from other species within the genus Calocybe based on their distinct morphological characteristics. The primary distinguishing features of C.betulicola include its grayish-purple pileus, grayish-brown to dark purple stipe, smaller basidiomata, absence of cellular pileipellis, and its habitat on leaf litter within birch forests. Calocybecystidiosa is distinguished by its growth on the leaf litter of coniferous forests, a flesh-pink pileus, a fibrous stipe with a white tomentose covering at the base, non-cellular pileipellis, larger basidiospores, and the presence of cheilocystidia. The reconstruction of phylogenetic trees using combined ITS, nLSU, and tef1-α sequences, employing maximum likelihood and Bayesian inference analyses, showed that C.betulicola formed a cluster with C.decurrens, while C.cystidiosa clustered with C.vinacea. However, these two clusters formed separate branches themselves, which also supported the results obtained from our morphological studies. A key to the Calocybe species reported from northeast China is provided to facilitate future studies of the genus.

12.
bioRxiv ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38469153

RESUMO

Class-switched neutralizing antibody (nAb) production is rapidly induced upon many viral infections. However, due to the presence of multiple components in typical virions, the precise biochemical and biophysical signals from viral infections that initiate nAb responses remain inadequately defined. Using a reductionist system of synthetic virus-like structures (SVLS) containing minimal, highly purified biochemical components commonly found in enveloped viruses, here we show that a foreign protein on a virion-sized liposome can serve as a stand-alone danger signal to initiate class-switched nAb responses in the absence of cognate T cell help or Toll-like receptor signaling but requires CD19, the antigen (Ag) coreceptor on B cells. Introduction of internal nucleic acids (iNAs) obviates the need for CD19, lowers the epitope density (ED) required to elicit the Ab response and transforms these structures into highly potent immunogens that rival conventional virus-like particles in their ability to elicit strong Ag-specific IgG. As early as day 5 after immunization, structures harbouring iNAs and decorated with just a few molecules of surface Ag at doses as low as 100 ng induced all IgG subclasses of Ab known in mice and reproduced the IgG2a/2c restriction that has been long observed in live viral infections. These findings reveal a shared mechanism for nAb response upon viral infection. High ED is capable but not necessary for driving Ab secretion in vivo . Instead, even a few molecules of surface Ag, when combined with nucleic acids within these structures, can trigger strong antiviral IgG production. As a result, the signaling threshold for the induction of neutralizing IgG is set by dual signals originating from both ED on the surface and the presence of iNAs within viral particulate immunogens. One-sentence summary: Reconstitution of minimal viral signals necessary to initiate antiviral IgG.

13.
Ecotoxicol Environ Saf ; 272: 116085, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38342010

RESUMO

Zearalenone (ZEN) is a prevalent mycotoxin that severely impacts human and animal health. However, the possible interactions between ZEN exposure, pathogen infection, immune system, and reactive oxygen species (ROS) were rarely investigated. We studied the effects of early-life ZEN (50 µM) exposure on the immune response of Caenorhabditis elegans against Bacillus thuringiensis infection and the associated mechanisms. The transcriptomic responses of C. elegans after early-life ZEN exposure were investigated using RNA sequencing and followed by verification using quantitative PCR analysis. We also investigated the immune responses of the worms through B. thuringiensis killing assays and by measuring oxidative stress. The transcriptomics result showed that early-life exposure to ZEN resulted in 44 differentially expressed genes, 7 of which were protein-coding genes with unknown functions. The Gene Ontology analysis suggested that metabolic processes and immune response were among the most significantly enriched biological processes, and the KEGG analysis suggested that lysosomes and metabolic pathways were the most significantly enriched pathways. The ZEN-exposed worms exhibited significantly reduced survival after 24-h B. thuringiensis infection, reaching near 100% mortality compared to 60% of the controls. Using qRT-PCR assay, we found that ZEN further enhanced the expression of immunity genes lys-6, spp-1, and clec-60 after B. thuringiensis infection. A concurrently enhanced ROS accumulation was also observed for ZEN-exposed worms after B. thuringiensis infection, which was 1.2-fold compared with the controls. Moreover, ZEN exposure further enhanced mRNA expression of catalases (ctl-1 and ctl-2) and increased catalase protein activity after B. thuringiensis exposure compared with their non-exposed counterparts, suggesting an elevated oxidative stress. This study suggests that early-life exposure to mycotoxin zearalenone overstimulates immune responses involving spp-17, clec-52, and clec-56, resulting in excessive ROS production, enhanced oxidative stress as indicated by aggravated ctl expression and activity, and a decline in host resistance to pathogenic infection which ultimately leads to increased mortality under B. thuringiensis infection. Our findings provide evidence that could improve our understanding on the potential interactions between mycotoxin zearalenone and pathogens.


Assuntos
Bacillus thuringiensis , Micotoxinas , Zearalenona , Animais , Humanos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Zearalenona/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Micotoxinas/metabolismo , Estresse Oxidativo , Antioxidantes/metabolismo , Imunidade
14.
J Chin Med Assoc ; 87(4): 369-376, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38334988

RESUMO

BACKGROUND: Intensive care unit (ICU) mortality prediction helps to guide therapeutic decision making for critically ill patients. Several scoring systems based on statistical techniques have been developed for this purpose. In this study, we developed a machine-learning model to predict patient mortality in the very early stage of ICU admission. METHODS: This study was performed with data from all patients admitted to the intensive care units of a tertiary medical center in Taiwan from 2009 to 2018. The patients' comorbidities, co-medications, vital signs, and laboratory data on the day of ICU admission were obtained from electronic medical records. We constructed random forest and extreme gradient boosting (XGBoost) models to predict ICU mortality, and compared their performance with that of traditional scoring systems. RESULTS: Data from 12,377 patients was allocated to training (n = 9901) and testing (n = 2476) datasets. The median patient age was 70.0 years; 9210 (74.41%) patients were under mechanical ventilation in the ICU. The areas under receiver operating characteristic curves for the random forest and XGBoost models (0.876 and 0.880, respectively) were larger than those for the Acute Physiology and Chronic Health Evaluation II score (0.738), Sequential Organ Failure Assessment score (0.747), and Simplified Acute Physiology Score II (0.743). The fraction of inspired oxygen on ICU admission was the most important predictive feature across all models. CONCLUSION: The XGBoost model most accurately predicted ICU mortality and was superior to traditional scoring systems. Our results highlight the utility of machine learning for ICU mortality prediction in the Asian population.


Assuntos
Estado Terminal , Unidades de Terapia Intensiva , Humanos , Idoso , Hospitais , Hospitalização , Aprendizado de Máquina
15.
J Hered ; 115(3): 292-301, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38364316

RESUMO

Biodiversity conservation is a top priority in the face of global environmental change, and the practical restoration of biodiversity has emerged as a key objective. Nevertheless, the question of how to effectively contribute to biodiversity restoration and identify suitable systems for such efforts continues to present major challenges. By using genome-wide SNP data, our study revealed that populations from different mountain ranges of the Formosan Long-Arm Scarab beetle, a flagship species that receives strict protection, exhibited a single genetic cluster with no subdivision. Additionally, our result implied an association between the demographic history and historical fluctuations in climate and environmental conditions. Furthermore, we showed that, despite a stable and moderately sized effective population over recent history, all the individuals we studied exhibited signs of genetic inbreeding. We argued that the current practice of protecting the species as one evolutionarily significant unit remains the best conservation plan and that recent habitat change may have led to the pattern of significant inbreeding. We closed by emphasizing the importance of conservation genetic studies in guiding policy decisions and highlighting the potential of genomic data for identifying ideal empirical systems for genetic rescue, or assisted gene flow studies.


Assuntos
Besouros , Conservação dos Recursos Naturais , Genética Populacional , Endogamia , Densidade Demográfica , Animais , Besouros/genética , Polimorfismo de Nucleotídeo Único , Ecossistema , Fluxo Gênico , Genômica/métodos , Variação Genética , Biodiversidade
16.
Cell Res ; 34(1): 13-30, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38163844

RESUMO

Oxidative phosphorylation (OXPHOS) consumes oxygen to produce ATP. However, the mechanism that balances OXPHOS activity and intracellular oxygen availability remains elusive. Here, we report that mitochondrial protein lactylation is induced by intracellular hypoxia to constrain OXPHOS. We show that mitochondrial alanyl-tRNA synthetase (AARS2) is a protein lysine lactyltransferase, whose proteasomal degradation is enhanced by proline 377 hydroxylation catalyzed by the oxygen-sensing hydroxylase PHD2. Hypoxia induces AARS2 accumulation to lactylate PDHA1 lysine 336 in the pyruvate dehydrogenase complex and carnitine palmitoyltransferase 2 (CPT2) lysine 457/8, inactivating both enzymes and inhibiting OXPHOS by limiting acetyl-CoA influx from pyruvate and fatty acid oxidation, respectively. PDHA1 and CPT2 lactylation can be reversed by SIRT3 to activate OXPHOS. In mouse muscle cells, lactylation is induced by lactate oxidation-induced intracellular hypoxia during exercise to constrain high-intensity endurance running exhaustion time, which can be increased or decreased by decreasing or increasing lactylation levels, respectively. Our results reveal that mitochondrial protein lactylation integrates intracellular hypoxia and lactate signals to regulate OXPHOS.


Assuntos
Proteínas Mitocondriais , Fosforilação Oxidativa , Camundongos , Animais , Proteínas Mitocondriais/metabolismo , Lisina/metabolismo , Hipóxia , Oxigênio , Lactatos
17.
Int J Biol Macromol ; 261(Pt 1): 129466, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242414

RESUMO

In order to modify colonic release behavior of lactoferrin (Lf), a hydrophobic composite nanofibrous carrier (CNC) was constructed by emulsion coaxial electrospinning. Ethylcellulose/pectin based water-in-oil emulsion and Lf-contained polyvinyl alcohol solution were used as shell and core fluids, respectively. An electrospinning diagram was first constructed to screen out suitable viscosity (51-82 cP) and conductivity (960-1300 µS/cm) of the dispersed phase of pectin solution for successful electrospinning of shell emulsion. Varying mass fraction of pectin solution (5 %-20 %) of shell emulsion during emulsion coaxial electrospinning obtained CNCs with different micro-structures, labeled as 5&95 CNC, 10&90 CNC, 15&85 CNC, 20&80 CNC. These CNCs all achieved colonic delivery of Lf (>95 %), and the time for complete release of Lf in simulated colon fermentation process were 10, 7, 5 and 3 h, respectively. That is, the greater the pectin content in CNC, the faster the release rate of stabilized Lf in colon. Lf release in simulated colon fermentation fluid involved complex mechanisms, in which diffusion release of Lf was dominant. Increasing colonic release rate of Lf enhanced its regulation effect on the expression levels of cell cycle arrest and apoptosis-related protein and promote its effective inhibition on the proliferation of HCT116 cell.


Assuntos
Celulose/análogos & derivados , Neoplasias do Colo , Nanofibras , Humanos , Pectinas/química , Lactoferrina/química , Emulsões/química , Neoplasias do Colo/tratamento farmacológico
18.
Exp Neurol ; 374: 114686, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38199507

RESUMO

Spinal cord injury often results in chronic loss of micturition control, which is featured by bladder hyperreflexia and detrusor sphincter dyssynergia. Previous studies showed that treatment of capsaicin reduces non-voiding bladder contractions in multiple animal injury models and human patients. However, its underlying neural mechanisms remain largely unknown. Here, by injecting a RetroAAV into the bladder wall, we specifically targeted TRPV1+, a capsaicin receptor, bladder afferent neurons. Morphometric analysis revealed borderline increase of the soma size and significant spinal axon sprouting of TRPV1+ bladder afferent neurons post a complete T8 spinal cord crush. We further demonstrated that chronic chemogenetic inhibition of these DRG neurons improved micturition recovery after SCI by increasing voiding efficiency and alleviating bladder hyperreflexia, along with reduced morphological changes caused by injury. Our study provided novel insights into the structural and functional changes of TRPV1+ bladder afferent post SCI and further supports the clinical use of capsaicin as an effective treatment to improve bladder functions in patients with SCI.


Assuntos
Traumatismos da Medula Espinal , Doenças da Bexiga Urinária , Animais , Humanos , Bexiga Urinária , Micção/fisiologia , Reflexo Anormal , Capsaicina/farmacologia , Neurônios Aferentes , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico , Canais de Cátion TRPV
19.
Stress Health ; : e3376, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265928

RESUMO

Controllability beliefs and goodness beliefs about emotion are two fundamental emotion beliefs. The present study considered both controllability beliefs and goodness beliefs to examine whether and how the emotion beliefs of adolescents influence their test anxiety. Besides self-reported test anxiety (sr-TA), the present study measured heart rate (HR) and galvanic skin response (GSR) using custom-designed wristbands during an exam as indicators of state test anxiety. The GSR was further decomposed into the tonic skin conductance level and the transient skin conductance response. The results revealed that, after controlling the goodness beliefs about anxiety, the controllability beliefs about emotion were negatively related to sr-TA. This relationship was mediated by suppression. The controllability beliefs about emotion were directly related to the integration of transient skin conductance responses of 5 min before the exam. They were also indirectly related to the integration of transient skin conductance responses of the exam period, whether including the 5 min before the exam or not, and HR during certain periods through suppression. Therefore, adolescents' controllability beliefs about emotion may have important implications for their test anxiety.

20.
Biochem Biophys Res Commun ; 696: 149472, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38241809

RESUMO

Lysosomal dysfunction and impaired autophagic flux are involved in the pathogenesis of lipotoxicity in the kidney. Here, we investigated the role of transcription factor EB (TFEB), a master regulator of autophagy-lysosomal pathway, in palmitic acid induced renal tubular epithelial cells injury. We examined lipid accumulation, autophagic flux, expression of Ps211-TFEB, and nuclear translocation of TFEB in HK-2 cells overloaded with palmitic acid (PA). By utilizing immunohistochemistry, we detected TFEB expression in renal biopsy tissues from patients with diabetic nephropathy and normal renal tissue adjacent to surgically removed renal carcinoma (controls), as well as kidney tissues from rat fed with high-fat diet (HFD) and low-fat diet (LFD). We found significant lipid accumulation, increased apoptosis, accompanied with elevated Ps211-TFEB, decreased nuclear TFEB, reduced lysosome biogenesis and insufficient autophagy in HK-2 cells treated with PA. Kidney tissues from patients with diabetic nephropathy had lower nuclear and total levels of TFEB than that in control kidney tissues. Level of renal nuclear TFEB in HFD rats was also lower than that in LFD rats. Exogenous overexpression of TFEB increased the nuclear TFEB level in HK-2 cells treated with PA, promoted lysosomal biogenesis, improved autophagic flux, reduced lipid accumulation and apoptosis. Our results collectively indicate that PA is a strong inducer for TFEB phosphorylation modification at ser211 accompanied with lower nuclear translocation of TFEB. Impairment of TFEB-mediated lysosomal biogenesis and function by palmitic acid may lead to insufficient autophagy and promote HK-2 cells injury.


Assuntos
Nefropatias Diabéticas , Ácido Palmítico , Ratos , Humanos , Animais , Ácido Palmítico/farmacologia , Ácido Palmítico/metabolismo , Nefropatias Diabéticas/metabolismo , Autofagia , Lisossomos/metabolismo , Células Epiteliais/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo
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