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1.
Environ Toxicol ; 39(2): 723-735, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37676967

RESUMEN

BACKGROUND: Lung adenocarcinoma (LUAD) is the prevalent malignancy worldwide. The aim is to explore differentially expressed genes (DEGs) associated with immune infiltration and survival time of LUAD patients, and predict transcriptional factors for shedding new light on molecular mechanisms and individual therapy of LUAD. METHOD: ScRNA-seq data of LUAD patients was downloaded from GSE148071 and analyzed by R packages. The clustering and protein-protein interaction network were constructed for screening DEGs. Gene Set Enrichment Analysis (GSEA) and GO enrichment analysis were performed in epithelial cell subgroups with high differentiation potential. Potential regulatory transcription factors were predicted. RESULTS: Sixteen epithelial cell types were required and top 20 genes were identified on cell subgroup Epi4 with the highest differentiation potential associated with poor prognosis of LUAD in PPI network. GSEA and GO annotation results showed that cell subgroup Epi4 was enriched in the biological processes of cell proliferation and energy metabolism, and positively regulated the function of cell proliferation. TPI1 was significantly highly expressed in LUAD samples (p < .0001). TPI1 demonstrated a negative correlation with the infiltration levels of CD8+ T cells, CD4+ T cells, B cells, and activated mast cells, whilst manifesting a positive correlation with the infiltration levels of resident mast cells, Th2 cells, and MDSC. Epi4 was regulated by transcription factors MXD3 and GATA4. CONCLUSION: Overexpression of TPI1 was identified as a novel biomarker for LUAD, and potential regulatory transcription factors MXD3 and GATA4 regulated the proliferation of LUAD with the poor prognosis, which may serve as potential targets to suppress the proliferation of LUAD.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Transcriptoma , Neoplasias Pulmonares/genética , Células Epiteliales , Factores de Transcripción , Análisis de Secuencia de ARN
2.
J Virol ; 96(13): e0042022, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35658530

RESUMEN

Human noroviruses (huNoVs) cause epidemic acute gastroenteritis using histo-blood group antigens (HBGAs) as host receptors or attachment factors to initiate an infection. While most huNoVs have been shown to bind HBGAs, some known clinical isolates, such as GI.3 DSV and VA115, do not recognize any HBGAs and thus the molecular mechanism behind their infections remains elusive. In this study, we provided both phenotypic and structural evidence to show that huNoV DSV and VA115 recognize a group of glycans with terminal galactoses as ligands. First, through glycan array we found that both DSV and VA115 protruding (P) domain proteins bound two oligosaccharides that share common terminal galactoses. Then, by determination of the crystal structures of DSV/VA115 P proteins in complex with Galα1-3Galß1-4Glc and/or NA2 N-Glycan, respectively, we showed that the terminal galactose is the main saccharide recognized by the two viral proteins. Our data demonstrated that GI huNoVs can interact with non-HBGA glycans through their conserved galactose binding site, shedding light on the mechanism of huNoV adaptation through recognizing new glycan receptors to facilitate their widespread nature in human population. These findings are also of significance in strategy development for huNoV control and prevention, as well as development of antiviral drugs. IMPORTANCE Human noroviruses (huNoVs) are the most important viral pathogens causing epidemic acute gastroenteritis worldwide. Previous studies indicated that histo-blood group antigens (HBGAs) are critical host-susceptibility factors affecting huNoV host susceptibility, host range, and probably prevalence. However, certain huNoVs, such as GI.3 DSV and VA115, do not recognize any HBGAs. This implies that other unknown host factors might exist and the molecular mechanism underlying their host receptor recognition or attachment remains elusive. In this study, we found that purified capsid protruding domain proteins from two GI.3 huNoVs specifically bind two glycans that contain a common terminal galactose. We solved the crystal structures of the complexes at atomic resolution and validated the vital amino acids involved in glycan recognition. Our findings elucidate the mechanism of GI.3 huNoV-non-HBGA glycan interaction, which explains why GI.3 virus strains could not bind human HBGAs, paving a way to the prevention and treatment of huNoV-associated diseases.


Asunto(s)
Antígenos de Grupos Sanguíneos , Galactosa , Gastroenteritis , Norovirus , Sitios de Unión , Antígenos de Grupos Sanguíneos/metabolismo , Proteínas de la Cápside/metabolismo , Galactosa/metabolismo , Gastroenteritis/fisiopatología , Humanos , Norovirus/metabolismo , Unión Proteica
3.
Appl Environ Microbiol ; 89(9): e0097923, 2023 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-37681950

RESUMEN

Bifidobacterium is the dominant genus, particularly in the intestinal tract niche of healthy breast-fed infants, and many of these strains have been proven to elicit positive effects on infant development. In addition to its effective antimicrobial activity against detrimental microorganisms, it helps to improve the intestinal microbiota balance. The isolation and identification of bacteriocins from Bifidobacterium have been limited since the mid-1980s, leading to an underestimation of its ability for bacteriocin production. Here, we employed a silicon-based search strategy to mine 354 putative bacteriocin gene clusters (BGCs), most of which have never been reported, from the genomes of 759 Bifidobacterium strains distributed across 9 species. Consistent with previous reports, most Bifidobacterium strains did not carry or carry only a single BGC; however, Bifidobacterium longum subsp. infantis, in contrast to other Bifidobacterium species, carried numerous BGCs, including lanthipeptides, lasso peptides, thiopeptides, and class IId bacteriocins. The antimicrobial activity of the crude bacteriocins and transcription analysis confirmed its potential for bacteriocin biosynthesis. Additionally, we investigated the association of bacteriocins with the phylogenetic positions of their homologs from other genera and niches. In conclusion, this study re-examines a few Bifidobacterium species traditionally regarded as a poor source of bacteriocins. These bacteriocin genes impart a competitive advantage to Bifidobacterium in colonizing the infant intestinal tract. IMPORTANCE Development of the human gut microbiota commences from birth, with bifidobacteria being among the first colonizers of the newborn intestinal tract and dominating it for a considerable period. To date, the genetic basis for the successful adaptation of bifidobacteria to this particular niche remains unclear since studies have mainly focused on glycoside hydrolase and adhesion-related genes. Bacteriocins are competitive factors that help producers maintain colonization advantages without destroying the niche balance; however, they have rarely been reported in Bifidobacterium. The advancement in sequencing methods and bacteriocin databases enables the use of a silicon-based search strategy for the comprehensive and rapid re-evaluation of the bacteriocin distribution of Bifidobacterium. Our study revealed that B. infantis carries abundant bacteriocin biosynthetic gene clusters for the first time, presenting new evidence regarding the competitive interactions of Bifidobacterium in the infant intestinal tract.


Asunto(s)
Antiinfecciosos , Bacteriocinas , Lactante , Recién Nacido , Niño , Femenino , Humanos , Bifidobacterium/genética , Bacteriocinas/genética , Filogenia , Silicio , Bifidobacterium longum subspecies infantis , Familia de Multigenes
4.
Ecotoxicol Environ Saf ; 252: 114596, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36738609

RESUMEN

The benthic gastropods Bellamya aeruginosa (B. aeruginosa) is ubiquitous in freshwater in China and neighboring countries with great edible value. It has been recognized as a potential manipulator to control harmful algal blooms due to its filtration on algal cells. In this study, the control effect of B. aeruginosa on toxic and non-toxic Microcystis aeruginosa (M. aeruginosa), and the accumulation and depuration of microcystins (MCs) in the snail were systematically explored. Results indicated that although toxic M. aeruginosa could protect itself via producing MCs, the introduction of B. aeruginosa could still effectively inhibit the algae with cell density below 1 × 106 cells/mL. Hepatopancreas was the primary target of MCs in all tissues of B. aeruginosa, presenting a maximum of 3089.60 ng/g DW when exposed to toxic M. aeruginosa of 1.0 × 107 cells/mL. The enrichment of MCs in other tissues following the order of digestive tract > gonad > mantle > muscle. Interestingly, snail could again excrete previously enriched MCs when transferred to non-toxic M. aeruginosa, giving rise to over 80% reduction of MCs in the body. After depuration, the estimated daily intake (EDI) of free MCs in intact individuals and the edible parts of B. aeruginosa were both lower than the tolerable daily intake (TDI). These results implicated that B. aeruginosa could control low density of M. aeruginosa in spring. Particularly, the snail could be perfectly safe to consume by purifying for a while after using as manipulator.


Asunto(s)
Microcystis , Animales , Humanos , Pseudomonas aeruginosa , Microcistinas/toxicidad , Caracoles , Floraciones de Algas Nocivas , China
5.
Angew Chem Int Ed Engl ; 62(36): e202305123, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37462518

RESUMEN

Tantalum nitride (Ta3 N5 ) has emerged as a promising photoanode material for photoelectrochemical (PEC) water splitting. However, the inefficient electron-hole separation remains a bottleneck that impedes its solar-to-hydrogen conversion efficiency. Herein, we demonstrate that a core-shell nanoarray photoanode of NbNx -nanorod@Ta3 N5 ultrathin layer enhances light harvesting and forms a spatial charge-transfer channel, which leads to the efficient generation and extraction of charge carriers. Consequently, an impressive photocurrent density of 7 mA cm-2 at 1.23 VRHE is obtained with an ultrathin Ta3 N5 shell thickness of less than 30 nm, accompanied by excellent stability and a low onset potential (0.46 VRHE ). Mechanistic studies reveal the enhanced performance is attributed to the high-conductivity NbNx core, high-crystalline Ta3 N5 mono-grain shell, and the intimate Ta-N-Nb interface bonds, which accelerate the charge-separation capability of the core-shell photoanode. This study demonstrates the key roles of nanostructure design in improving the efficiency of PEC devices.

6.
Int J Food Sci Nutr ; 73(2): 238-250, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34353205

RESUMEN

The prevalence of obesity and its associated diseases is increasing. In the current study, 15 obese subjects took part in a 12-week multiphase dietetic protocol incorporating an improved ketogenic diet (MDP-i-KD) (KYLLKS 201806). We investigated the effects of the MDP-i-KD on the anthropometric parameters and the gut microbiota of obese subjects. Our results showed that the MDP-i-KD led to significant reductions in body mass index in obese subjects. The MDP-i-KD significantly decreased the relative abundance of the Lachnospiraceae_ND3007_group, the Eubacterium_hallii_group, and Pseudomonas and Blautia. In addition, gut microbiota co-occurrence networks in obese subjects were restructured to a more healthy condition after weight loss. These results show that the MDP-i-KD enhanced weight loss, which may be associated with dietary-induced changes in the gut microbiome. Our results emphasise the importance of determining the interaction between the host and microbial cells to comprehensively understand the mechanism by which diet affects host physiology and the microbiota.


Asunto(s)
Dieta Cetogénica , Dietética , Microbioma Gastrointestinal , Humanos , Obesidad , Pérdida de Peso
7.
Entropy (Basel) ; 23(12)2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34945878

RESUMEN

In this paper, we study a slotted-time system where a base station needs to update multiple users at the same time. Due to the limited resources, only part of the users can be updated in each time slot. We consider the problem of minimizing the Age of Incorrect Information (AoII) when imperfect Channel State Information (CSI) is available. Leveraging the notion of the Markov Decision Process (MDP), we obtain the structural properties of the optimal policy. By introducing a relaxed version of the original problem, we develop the Whittle's index policy under a simple condition. However, indexability is required to ensure the existence of Whittle's index. To avoid indexability, we develop Indexed priority policy based on the optimal policy for the relaxed problem. Finally, numerical results are laid out to showcase the application of the derived structural properties and highlight the performance of the developed scheduling policies.

8.
J Virol ; 93(1)2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30333166

RESUMEN

Human noroviruses (huNoVs), which cause epidemic acute gastroenteritis, recognize histo-blood group antigens (HBGAs) as host attachment factors affecting host susceptibility. HuNoVs are genetically diverse, containing at least 31 genotypes in the two major genogroups (genogroup I [GI] and GII). Three GII genotypes, GII genotype 17 (GII.17), GII.13, and GII.21, form a unique genetic lineage, in which the GII.17 genotype retains the conventional GII HBGA binding site (HBS), while the GII.13/21 genotypes acquire a completely new HBS. To understand the molecular bases behind these evolutionary changes, we solved the crystal structures of the HBGA binding protruding domains of (i) an early GII.17 variant (the 1978 variant) that does not bind or binds weakly to HBGAs, (ii) the new GII.17 variant (the 2014/15 variant) that binds A/B/H antigens strongly via an optimized GII HBS, and (iii) a GII.13 variant (the 2010 variant) that binds the Lewis a (Lea) antigen via the new HBS. These serial, high-resolution structural data enable a comprehensive structural comparison to understand the evolutionary changes of the GII.17/13/21 lineage, including the emergence of the new HBS of the GII.13/21 sublineage and the possible HBS optimization of the recent GII.17 variant for an enhanced HBGA binding ability. Our study elucidates the structural adaptations of the GII.17/13/21 lineage through distinct evolutionary paths, which may allow a theory explaining huNoV adaptations and evolutions to be put forward.IMPORTANCE Our understanding of the molecular bases behind the interplays between human noroviruses and their host glycan ligands, as well as their evolutionary changes over time with alterations in their host ligand binding capability and host susceptibility, remains limited. By solving the crystal structures of the glycan ligand binding protruding (P) domains with or without glycan ligands of three representative noroviruses of the GII.17/13/21 genetic lineage, we elucidated the molecular bases of the human norovirus-glycan interactions of this special genetic lineage. We present solid evidence on how noroviruses of this genetic lineage evolved via different evolutionary paths to (i) optimize their glycan binding site for higher glycan binding function and (ii) acquire a completely new glycan binding site for new ligands. Our data shed light on the mechanism of the structural adaptations of human noroviruses through different evolutionary paths, facilitating our understanding of human norovirus adaptations, evolutions, and epidemiology.


Asunto(s)
Antígenos de Grupos Sanguíneos/metabolismo , Mutación , Norovirus/clasificación , Proteínas Virales/química , Sitios de Unión , Cristalografía por Rayos X , Evolución Molecular , Variación Genética , Humanos , Modelos Moleculares , Norovirus/química , Filogenia , Unión Proteica , Conformación Proteica , Dominios Proteicos , Proteínas Virales/metabolismo
9.
Mol Biol Rep ; 45(6): 1637-1646, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30215193

RESUMEN

Study on the binding properties of helicid by pepsin systematically using multi-spectroscopic techniques and molecular docking method, and these interactions comprise biological recognition at molecular level and backbone of biological significance in medicine concerned with the uses, effects, and modes of action of drugs. We investigated the mechanism of interaction between helicid and pepsin by using various spectroscopic techniques viz., fluorescence spectra, UV-Vis absorption spectra, circular dichroism (CD), 3D spectra, synchronous fluorescence spectra and molecular docking methods. The quenching mechanism associated with the helicid-pepsin interaction was determined by performing fluorescence measurements at different temperatures. From the experimental results show that helicid quenched the fluorescence intensity of pepsin via a combination of static and dynamic quenching process. The binding constants (Ka) at three temperatures (288, 298, and 308 K) were 7.940 × 107, 2.082 × 105 and 3.199 × 105 L mol-1, respectively, and the number of binding sites (n) were 1.44, 1.14, and 1.18, respectively. The n value is close to unity, which means that there is only one independent class of binding site on pepsin for helicid. Thermodynamic parameters at 298 K were calculated as follows: ΔHo (- 83.85 kJ mol-1), ΔGo (- 33.279 kJ mol-1), and ΔSo (- 169.72 J K-1 mol-1). Based on thermodynamic analysis, the interaction of helicid with pepsin is driven by enthalpy, and Van der Waals' forces and hydrogen bonds are the main forces between helicid and pepsin. A molecular docking study further confirmed the binding mode obtained by the experimental studies. The conformational changes in the structure of pepsin was confirmed by 3D fluorescence spectra and circular dichroism.


Asunto(s)
Benzaldehídos/química , Pepsina A/química , Sitios de Unión , Dicroismo Circular , Fluorescencia , Enlace de Hidrógeno , Medicina Tradicional China , Simulación del Acoplamiento Molecular/métodos , Unión Proteica/fisiología , Dominios Proteicos/fisiología , Espectrometría de Fluorescencia/métodos , Espectrofotometría Ultravioleta/métodos , Temperatura , Termodinámica
10.
PLoS Genet ; 11(12): e1005731, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26656736

RESUMEN

Nutrient availability has profound influence on development. In the nematode C. elegans, nutrient availability governs post-embryonic development. L1-stage larvae remain in a state of developmental arrest after hatching until they feed. This "L1 arrest" (or "L1 diapause") is associated with increased stress resistance, supporting starvation survival. Loss of the transcription factor daf-16/FOXO, an effector of insulin/IGF signaling, results in arrest-defective and starvation-sensitive phenotypes. We show that daf-16/FOXO regulates L1 arrest cell-nonautonomously, suggesting that insulin/IGF signaling regulates at least one additional signaling pathway. We used mRNA-seq to identify candidate signaling molecules affected by daf-16/FOXO during L1 arrest. dbl-1/TGF-ß, a ligand for the Sma/Mab pathway, daf-12/NHR and daf-36/oxygenase, an upstream component of the daf-12 steroid hormone signaling pathway, were up-regulated during L1 arrest in a daf-16/FOXO mutant. Using genetic epistasis analysis, we show that dbl-1/TGF-ß and daf-12/NHR steroid hormone signaling pathways are required for the daf-16/FOXO arrest-defective phenotype, suggesting that daf-16/FOXO represses dbl-1/TGF-ß, daf-12/NHR and daf-36/oxygenase. The dbl-1/TGF-ß and daf-12/NHR pathways have not previously been shown to affect L1 development, but we found that disruption of these pathways delayed L1 development in fed larvae, consistent with these pathways promoting development in starved daf-16/FOXO mutants. Though the dbl-1/TGF-ß and daf-12/NHR pathways are epistatic to daf-16/FOXO for the arrest-defective phenotype, disruption of these pathways does not suppress starvation sensitivity of daf-16/FOXO mutants. This observation uncouples starvation survival from developmental arrest, indicating that DAF-16/FOXO targets distinct effectors for each phenotype and revealing that inappropriate development during starvation does not cause the early demise of daf-16/FOXO mutants. Overall, this study shows that daf-16/FOXO promotes developmental arrest cell-nonautonomously by repressing pathways that promote larval development.


Asunto(s)
Proteínas de Caenorhabditis elegans/genética , Desarrollo Embrionario/genética , Factores de Transcripción Forkhead/genética , Insulina/genética , Neuropéptidos/genética , Receptores Citoplasmáticos y Nucleares/genética , Somatomedinas/genética , Factor de Crecimiento Transformador beta/genética , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/crecimiento & desarrollo , Proteínas de Caenorhabditis elegans/biosíntesis , Embrión no Mamífero , Factores de Transcripción Forkhead/biosíntesis , Regulación del Desarrollo de la Expresión Génica , Humanos , Insulina/metabolismo , Larva/genética , Larva/crecimiento & desarrollo , Neuropéptidos/biosíntesis , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Receptores Citoplasmáticos y Nucleares/biosíntesis , Transducción de Señal , Somatomedinas/metabolismo , Inanición , Factor de Crecimiento Transformador beta/biosíntesis
11.
PLoS Pathog ; 11(7): e1005025, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26147716

RESUMEN

Norovirus (NoV) causes epidemic acute gastroenteritis in humans, whereby histo-blood group antigens (HBGAs) play an important role in host susceptibility. Each of the two major genogroups (GI and GII) of human NoVs recognizes a unique set of HBGAs through a distinct binding interface that is conserved within a genogroup, indicating a distinct evolutionary path for each genogroup. Here, we characterize a Lewis a (Lea) antigen binding strain (OIF virus) in the GII.21 genotype that does not share the conserved GII binding interface, revealing a new evolution lineage with a distinct HBGA binding interface. Sequence alignment showed that the major residues contributing to the new HBGA binding interface are conserved among most members of the GII.21, as well as a closely related GII.13 genotype. In addition, we found that glycerol inhibits OIF binding to HBGAs, potentially allowing production of cheap antivirals against human NoVs. Taken together, our results reveal a new evolutionary lineage of NoVs selected by HBGAs, a finding that is important for understanding the diversity and widespread nature of NoVs.


Asunto(s)
Antígenos de Grupos Sanguíneos/metabolismo , Norovirus/genética , Proteínas Virales/química , Acoplamiento Viral , Secuencia de Aminoácidos , Sitios de Unión/genética , Evolución Biológica , Cristalografía por Rayos X , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Filogenia , Unión Proteica/genética , Conformación Proteica , Proteínas Virales/genética , Proteínas Virales/metabolismo
12.
J Biol Chem ; 290(20): 12899-907, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25847243

RESUMEN

Toxic ribosome-inactivating proteins abolish cell viability by inhibiting protein synthesis. Ricin, a member of these lethal proteins, is a potential bioterrorism agent. Despite the grave challenge posed by these toxins to public health, post-exposure treatment for intoxication caused by these agents currently is unavailable. In this study, we report the identification of baicalin extracted from Chinese herbal medicine as a compound capable of inhibiting the activity of ricin. More importantly, post-exposure treatment with baicalin significantly increased the survival of mice poisoned by ricin. We determined the mechanism of action of baicalin by solving the crystal structure of its complex with the A chain of ricin (RTA) at 2.2 Å resolution, which revealed that baicalin interacts with two RTA molecules at a novel binding site by hydrogen bond networks and electrostatic force interactions, suggesting its role as molecular glue of the RTA. Further biochemical and biophysical analyses validated the amino acids directly involved in binding the inhibitor, which is consistent with the hypothesis that baicalin exerts its inhibitory effects by inducing RTA to form oligomers in solution, a mechanism that is distinctly different from previously reported inhibitors. This work offers promising leads for the development of therapeutics against ricin and probably other ribosome-inactivating proteins.


Asunto(s)
Inhibidores Enzimáticos , Flavonoides , Multimerización de Proteína , Ricina/química , Ricina/toxicidad , Animales , Cristalografía por Rayos X , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Flavonoides/química , Flavonoides/farmacología , Medicina Tradicional China , Ratones , Ratones Endogámicos BALB C , Estructura Cuaternaria de Proteína
13.
J Phys Ther Sci ; 28(6): 1791-4, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27390417

RESUMEN

[Purpose] This study assessed the effects of combined application of raloxifene and aerobic exercise on senile osteoporosis. [Subjects and Methods] A total of 70 elderly patients with osteoporosis, who treated at our hospital between April 2013 and August 2014, were divided into equal-sized observation and control groups. The control group was administered raloxifene, whereas the observation group received raloxifene treatment plus aerobic exercise. [Results] Outpatient outcomes were considered dependent variables. After treatment, the two groups differed significantly in terms of lumbar spine (L2-L4) and proximal femoral bone mineral density. The urine pyridine/creatinine ratio decreased significantly and serum calcitonin level increased significantly in the observation group. These differences were statistically significant. [Conclusion] Raloxifene combined with aerobic exercise therapy significantly improves bone density and promotes bone formation in patients with senile osteoporosis.

14.
Dev Biol ; 394(2): 314-26, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25128585

RESUMEN

Caenorhabditis elegans larvae reversibly arrest development in the first larval stage in response to starvation (L1 arrest or L1 diapause). Insulin-like signaling is a critical regulator of L1 arrest. However, the C. elegans genome encodes 40 insulin-like peptides, and it is unknown which peptides participate in nutritional control of L1 development. Work in other contexts has revealed that insulin-like genes can promote development ("agonists") or developmental arrest ("antagonists"), suggesting that such agonists promote L1 development in response to feeding. We measured mRNA expression dynamics with high temporal resolution for all 40 insulin-like genes during entry into and recovery from L1 arrest. Nutrient availability influences expression of the majority of insulin-like genes, with variable dynamics suggesting complex regulation. We identified thirteen candidate agonists and eight candidate antagonists based on expression in response to nutrient availability. We selected ten candidate agonists (daf-28, ins-3, ins-4, ins-5, ins-6, ins-7, ins-9, ins-26, ins-33 and ins-35) for further characterization in L1 stage larvae. We used destabilized reporter genes to determine spatial expression patterns. Expression of candidate agonists is largely overlapping in L1 stage larvae, suggesting a role of the intestine, chemosensory neurons ASI and ASJ, and the interneuron PVT in control of L1 development. Transcriptional regulation of candidate agonists is most significant in the intestine, as if internal nutrient status is a more important influence on transcription than sensory perception. Phenotypic analysis of single and compound deletion mutants did not reveal effects on L1 developmental dynamics, though simultaneous disruption of ins-4 and daf-28 increases survival of L1 arrest. Furthermore, overexpression of ins-4, ins-6 or daf-28 alone decreases survival and promotes cell division during starvation. These results suggest extensive functional overlap among insulin-like genes in nutritional control of L1 development while highlighting the role of ins-4, daf-28 and to a lesser extent ins-6.


Asunto(s)
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica/fisiología , Hormonas Peptídicas/metabolismo , ARN Mensajero/metabolismo , Receptor de Insulina/metabolismo , Análisis de Varianza , Animales , Proteínas de Caenorhabditis elegans/genética , Perfilación de la Expresión Génica , Insulina/agonistas , Insulina/metabolismo , Insulinas , Mucosa Intestinal/metabolismo , Larva/crecimiento & desarrollo , Larva/metabolismo , Modelos Logísticos , Hormonas Peptídicas/genética , Análisis de Supervivencia
15.
Antimicrob Agents Chemother ; 59(11): 7054-60, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26349825

RESUMEN

Shiga-like toxins (Stxs), produced by pathogenic Escherichia coli, are a major virulence factor involved in severe diseases in human and animals. These toxins are ribosome-inactivating proteins, and treatment for diseases caused by them is not available. Therefore, there is an urgent need for agents capable of effectively targeting this lethal toxin. In this study, we identified baicalin, a flavonoid compound used in Chinese traditional medicine, as a compound against Shiga-like toxin 2 (Stx2). We found that baicalin significantly improves renal function and reduces Stx2-induced lethality in mice. Further experiments revealed that baicalin induces the formation of oligomers by the toxin by direct binding. We also identified the residues important for such interactions and analyzed their roles in binding baicalin by biophysical and biochemical analyses. Our results establish baicalin as a candidate compound for the development of therapeutics against diseases caused by Stxs.


Asunto(s)
Flavonoides/uso terapéutico , Toxina Shiga II/metabolismo , Toxina Shiga II/toxicidad , Animales , Flavonoides/química , Células HeLa , Humanos , Riñón/efectos de los fármacos , Riñón/metabolismo , Ratones , Toxina Shiga II/química
16.
Opt Lett ; 40(22): 5136-9, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26565818

RESUMEN

Multi-wavelength laser arrays (MLAs) with a high wavelength-spacing precision are designed and fabricated. The MLAs are realized by the reconstruction-equivalent chirp (REC) technique, and anti-reflection structures are used to decrease the wavelength deviation. Six multi-wavelength laser arrays are fabricated and tested. Statistical results show that 81.1% of all 95 lasers have wavelength deviations within ±0.1 nm, and all of them are within ±0.2 nm. The mean wavelength spacing is 1.605 nm, and the standard deviation is 0.132 nm.

17.
Waste Manag ; 174: 558-567, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38141373

RESUMEN

Studies of per- and polyfluoroalkyl substances (PFAS) fluctuations at landfills have focused on municipal solid waste (MSW) leachate. Few studies exist that evaluate fluctuations (defined by the coefficient of variation, CV) in MSW incinerator ash (MSWA) landfill leachate and that evaluate PFAS fluctuations in stormwater, groundwater, and treated liquids on-site. In this study, aqueous landfill samples (leachate, treated leachate, stormwater, gas condensate, ambient groundwater, and effluent from a groundwater remediation system) were collected from a MSW and an MSWA landfill geographically located within close proximity (less than 40 km). The objective of this study was to compare the leachate compositions between these two landfill types and to evaluate temporal variations. Results indicated that the CV of total detected PFAS concentrations in leachate was higher for the MSW landfill (CV = 43 %) compared to the MSWA landfill (CV = 16 %). The total detected PFAS concentration in MSW leachate samples (mean: 9641 ng/L) was higher than in MSWA leachate samples (mean: 2621 ng/L) (p < 0.05). Within a landfill, PFAS concentrations were correlated (rs > 0.6, p < 0.05) with alkalinity, total organic carbon (TOC), and ammonia. Results from the on-site leachate treatment system at the MSW landfill indicated reductions in COD, TOC, and ammonia; however, the ∑26PFAS concentration increased 3 % after the treatment. Overall, results demonstrated that differences between landfill types and fluctuations in PFAS within landfills should be considered when designing landfill leachate collection and treatment systems to remove PFAS. The comparative analysis in this study can provide insights into optimizing leachate management for MSW and MSWA landfills.


Asunto(s)
Fluorocarburos , Eliminación de Residuos , Contaminantes Químicos del Agua , Residuos Sólidos/análisis , Amoníaco/análisis , Contaminantes Químicos del Agua/análisis , Instalaciones de Eliminación de Residuos , Fluorocarburos/análisis
18.
Waste Manag ; 175: 348-359, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38252979

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) have been found at high levels within landfill environments. To assess PFAS distributions, this study aimed to evaluate PFAS mass flux leached from disposed solid waste and within landfill reservoirs by mass balance analyses for two full-scale operational Florida landfills. PFAS mass flux in different aqueous components within landfills were estimated based on PFAS concentrations and water flow rates. For PFAS concentration, 26 PFAS, including 18 perfluoroalkyl acids (PFAAs) and 8 PFAA-precursors, were measured in samples collected from the landfills or estimated based on previous studies. Flow rates of aqueous components (rainfall, evapotranspiration, runoff, stormwater, groundwater, leakage, gas condensate, and leachate) were evaluated through the Hydrologic Evaluation of Landfill Performance model, water balance, and Darcy's Law. Results showed that the average PFAS mass flux leached from the solid waste standardized by area was estimated as 36.8 g/ha-yr, which was approximately 1 % to 3 % of the total amount of PFAS within the solid waste. The majority of PFAS leached from the solid waste (95 % to 97 %) is captured by the leachate collection system, with other aqueous components representing much smaller fractions (stormwater system at 3 % to 5 %, and gas condensate and groundwater at < 1 %). Also, based on the results, we estimate that PFAS releases will likely occur at least over 40 years. Overall, these results can help prioritize components for waste management and PFAS treatment during the anticipated landfill release periods.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Residuos Sólidos/análisis , Contaminantes Químicos del Agua/análisis , Florida , Instalaciones de Eliminación de Residuos , Agua , Fluorocarburos/análisis
19.
Chemosphere ; 355: 141719, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38513956

RESUMEN

PER: and polyfluoroalkyl substances (PFAS) have been measured in aqueous components within landfills. To date, the majority of these studies have been conducted in Florida. This current study aimed to evaluate PFAS concentrations in aqueous components (leachate, gas condensate, stormwater, and groundwater) from four landfills located outside of Florida, in Pennsylvania, Colorado, and Wisconsin (2 landfills). The Pennsylvania landfill also provided the opportunity to assess a leachate treatment system. Sample analyses were consistent across studies including the measurements of 26 PFAS and physical-chemical parameters. For the four target landfills, average PFAS concentrations were 6,900, 22,000, 280, and 260 ng L-1 in the leachate, gas condensate, stormwater, and groundwater, respectively. These results were not significantly different than those observed for landfills in Florida except for the significantly higher PFAS concentrations in gas condensate compared to leachate. For on-site treatment at the Pennsylvania landfill, results suggest that the membrane biological bioreactor (MBBR) system performed similarly as aeration-based leachate treatment systems at Florida landfills resulting in no significant decreases in ∑26PFAS. Overall, results suggest a general consistency across US regions in PFAS concentrations within different landfill liquid types, with the few differences observed likely influenced by landfill design and local climate. Results confirm that leachate exposed to open air (e.g., in trenches or in treatment systems) have lower proportions of perfluoroalkyl acid precursors relative to leachate collected in enclosed pipe systems. Results also confirm that landfills without bottom liner systems may have relatively higher PFAS levels in adjacent groundwater and that landfills in wetter climates tend to have higher PFAS concentrations in leachate.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Colorado , Wisconsin , Pennsylvania , Biopelículas , Reactores Biológicos , Instalaciones de Eliminación de Residuos , Fluorocarburos/análisis
20.
CNS Neurosci Ther ; 30(2): e14403, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37577804

RESUMEN

AIM: Cinchonine (CN) and its isomer cinchonidine (CD), two of the common cinchona alkaloids, are wildly used as antimalarial drugs. However, the effects of CN and CD on the auditory system are unknown. METHODS: Molecular docking and molecular dynamics (MD) simulation were used for predicting effective drugs. The CCK-8 assay was conducted for assessing cell viability in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells. MitoSox Red staining revealed reactive oxygen species (ROS) amounts. TMRM staining was used to assess the mitochondrial membrane potential (ΔΨm). Immunofluorescence staining of myosin 7a was used to examine hair cells (HCs) in cisplatin-treated neonatal mouse cochlear explants, while TUJ-1 immunostaining was used for the detection of spiral ganglion neurons (SGNs). Cleaved caspase-3 and TUNEL immunostaining were utilized for apoptosis assessment. Immunoblot was carried out to detect PI3K-AKT signaling effectors. RESULTS: Pretreatment with CN or CD significantly increased cell viability and reduced mitochondrial dysfunction and ROS accumulation in cisplatin-treated HEI-OC1 cells. Immunofluorescent staining of cochlear explants showed that CN and CD attenuated cisplatin-induced damage to SGNs and HCs. Immunoblot revealed that CN and CD downregulated the expression of cleaved caspase-3 and activated PI3K-AKT signaling in cisplatin-injured HEI-OC1 cells. CONCLUSION: CD and CN can reduce ototoxicity caused by cisplatin and might help treat cisplatin-associated hearing loss.


Asunto(s)
Antineoplásicos , Alcaloides de Cinchona , Ototoxicidad , Ratones , Animales , Cisplatino/toxicidad , Antineoplásicos/toxicidad , Proteínas Proto-Oncogénicas c-akt/metabolismo , Caspasa 3/metabolismo , Fosfatidilinositol 3-Quinasas , Especies Reactivas de Oxígeno/metabolismo , Ototoxicidad/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Alcaloides de Cinchona/farmacología , Apoptosis
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