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1.
N Engl J Med ; 390(8): 712-722, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38381674

RESUMO

BACKGROUND: Biomarker changes that occur in the period between normal cognition and the diagnosis of sporadic Alzheimer's disease have not been extensively investigated in longitudinal studies. METHODS: We conducted a multicenter, nested case-control study of Alzheimer's disease biomarkers in cognitively normal participants who were enrolled in the China Cognition and Aging Study from January 2000 through December 2020. A subgroup of these participants underwent testing of cerebrospinal fluid (CSF), cognitive assessments, and brain imaging at 2-year-to-3-year intervals. A total of 648 participants in whom Alzheimer's disease developed were matched with 648 participants who had normal cognition, and the temporal trajectories of CSF biochemical marker concentrations, cognitive testing, and imaging were analyzed in the two groups. RESULTS: The median follow-up was 19.9 years (interquartile range, 19.5 to 20.2). CSF and imaging biomarkers in the Alzheimer's disease group diverged from those in the cognitively normal group at the following estimated number of years before diagnosis: amyloid-beta (Aß)42, 18 years; the ratio of Aß42 to Aß40, 14 years; phosphorylated tau 181, 11 years; total tau, 10 years; neurofilament light chain, 9 years; hippocampal volume, 8 years; and cognitive decline, 6 years. As cognitive impairment progressed, the changes in CSF biomarker levels in the Alzheimer's disease group initially accelerated and then slowed. CONCLUSIONS: In this study involving Chinese participants during the 20 years preceding clinical diagnosis of sporadic Alzheimer's disease, we observed the time courses of CSF biomarkers, the times before diagnosis at which they diverged from the biomarkers from a matched group of participants who remained cognitively normal, and the temporal order in which the biomarkers became abnormal. (Funded by the Key Project of the National Natural Science Foundation of China and others; ClinicalTrials.gov number, NCT03653156.).


Assuntos
Doença de Alzheimer , Biomarcadores , Disfunção Cognitiva , Humanos , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Estudos de Casos e Controles , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Proteínas tau/líquido cefalorraquidiano , Seguimentos
2.
PLoS Biol ; 22(3): e3002565, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38527087

RESUMO

K+ channels regulate morphogens to scale adult fins, but little is known about what regulates the channels and how they control morphogen expression. Using the zebrafish pectoral fin bud as a model for early vertebrate fin/limb development, we found that K+ channels also scale this anatomical structure, and we determined how one K+-leak channel, Kcnk5b, integrates into its developmental program. From FLIM measurements of a Förster Resonance Energy Transfer (FRET)-based K+ sensor, we observed coordinated decreases in intracellular K+ levels during bud growth, and overexpression of K+-leak channels in vivo coordinately increased bud proportions. Retinoic acid, which can enhance fin/limb bud growth, decreased K+ in bud tissues and up-regulated regulator of calcineurin (rcan2). rcan2 overexpression increased bud growth and decreased K+, while CRISPR-Cas9 targeting of rcan2 decreased growth and increased K+. We observed similar results in the adult caudal fins. Moreover, CRISPR targeting of Kcnk5b revealed that Rcan2-mediated growth was dependent on the Kcnk5b. We also found that Kcnk5b enhanced depolarization in fin bud cells via Na+ channels and that this enhanced depolarization was required for Kcnk5b-enhanced growth. Lastly, Kcnk5b-induced shha transcription and bud growth required IP3R-mediated Ca2+ release and CaMKK activity. Thus, we provide a mechanism for how retinoic acid via rcan2 can regulate K+-channel activity to scale a vertebrate appendage via intercellular Ca2+ signaling.


Assuntos
Cálcio , Peixe-Zebra , Animais , Peixe-Zebra/genética , Cálcio/metabolismo , Tretinoína , Nadadeiras de Animais/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
3.
Brain ; 147(6): 2185-2202, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38242640

RESUMO

Heterozygous de novo mutations in the neuronal protein Munc18-1/STXBP1 cause syndromic neurological symptoms, including severe epilepsy, intellectual disability, developmental delay, ataxia and tremor, summarized as STXBP1 encephalopathies. Although haploinsufficiency is the prevailing disease mechanism, it remains unclear how the reduction in Munc18-1 levels causes synaptic dysfunction in disease as well as how haploinsufficiency alone can account for the significant heterogeneity among patients in terms of the presence, onset and severity of different symptoms. Using biochemical and cell biological readouts on mouse brains, cultured mouse neurons and heterologous cells, we found that the synaptic Munc18-1 interactors Doc2A and Doc2B are unstable in the absence of Munc18-1 and aggregate in the presence of disease-causing Munc18-1 mutants. In haploinsufficiency-mimicking heterozygous knockout neurons, we found a reduction in Doc2A/B levels that is further aggravated by the presence of the disease-causing Munc18-1 mutation G544D as well as an impairment in Doc2A/B synaptic targeting in both genotypes. We also demonstrated that overexpression of Doc2A/B partially rescues synaptic dysfunction in heterozygous knockout neurons but not heterozygous knockout neurons expressing G544D Munc18-1. Our data demonstrate that STXBP1 encephalopathies are not only characterized by the dysfunction of Munc18-1 but also by the dysfunction of the Munc18-1 binding partners Doc2A and Doc2B, and that this dysfunction is exacerbated by the presence of a Munc18-1 missense mutant. These findings may offer a novel explanation for the significant heterogeneity in symptoms observed among STXBP1 encephalopathy patients.


Assuntos
Proteínas de Ligação ao Cálcio , Proteínas Munc18 , Mutação , Proteínas do Tecido Nervoso , Neurônios , Sinapses , Animais , Humanos , Camundongos , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Células Cultivadas , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Munc18/genética , Proteínas Munc18/metabolismo , Mutação/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Sinapses/metabolismo , Sinapses/genética
4.
Biochemistry ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329238

RESUMO

Numerous organic molecules are known to inhibit the main protease (MPro) of SARS-CoV-2, the pathogen of Coronavirus Disease 2019 (COVID-19). Guided by previous research on zinc-ligand inhibitors of MPro and zinc-dependent histone deacetylases (HDACs), we identified BRD4354 as a potent inhibitor of MPro. The in vitro protease activity assays show that BRD4354 displays time-dependent inhibition against MPro with an IC50 (concentration that inhibits activity by 50%) of 0.72 ± 0.04 µM after 60 min of incubation. Inactivation follows a two-step process with an initial rapid binding step with a KI of 1.9 ± 0.5 µM followed by a second slow inactivation step, kinact,max of 0.040 ± 0.002 min-1. Native mass spectrometry studies indicate that a covalent intermediate is formed where the ortho-quinone methide fragment of BRD4354 forms a covalent bond with the catalytic cysteine C145 of MPro. Based on these data, a Michael-addition reaction mechanism between MPro C145 and BRD4354 was proposed. These results suggest that both preclinical testing of BRD4354 and structure-activity relationship studies based on BRD4354 are warranted to develop more effective anti-COVID therapeutics.

5.
J Cell Physiol ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801215

RESUMO

Syntaxin of plant (SYP) plays a crucial role in SNARE-mediated membrane trafficking during endocytic and secretory pathways, contributing to the regulation and execution of plant immunity against pathogens. Verticillium wilt is among the most destructive fungal diseases affecting cotton worldwide. However, information regarding SYP family genes in cotton is scarce. Through genome-wide identification and transcriptome profiling, we identified GhSYP121, a Qa SNARE gene in Gossypium hirsutum. GhSYP121 is notably induced by Verticillium dahliae, the causal agent of Verticillium wilt in cotton, and acts as a negative regulator of defense against V. dahliae. This is evidenced by the reduced resistance of GhSYP121-deficient cotton and the increased susceptibility of GhSYP121-overexpressing lines. Furthermore, the activation of the salicylic acid (SA) pathway by V. dahliae is inversely correlated with the expression level of GhSYP121. GhSYP121 interacts with its cognate SNARE component, GhSNAP33, which is required for the penetration resistance against V. dahliae in cotton. Collectively, GhSYP121, as a member of the cotton SNARE complex, is involved in regulating the SA pathway during plant defense against V. dahliae. This finding enhances our understanding of the potential role of GhSYP121 in these distinct pathways that contribute to plant defense against V. dahliae infection.

6.
Plant Cell Physiol ; 65(5): 781-789, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38447119

RESUMO

MicroRNAs (miRNAs) are known to play critical roles in regulating rice agronomic traits through mRNA cleavage or translational repression. Our previous study indicated that miR5504 regulates plant height by affecting cell proliferation and expansion. Here, the two independent homozygous mir5504 mutants (CR1 and CR2) and overexpression lines (OE1 and OE2) were further used to investigate the functions of miR5504. The panicle length, 1000-grain weight and grain yield per plant of miR5504-OE lines were identical to those of Nipponbare (NIP), but the 1000-grain weight of mir5504 mutants was reduced by about 10% and 9%, respectively. Meanwhile, the grain width and thickness of mir5504 mutants decreased significantly by approximately 10% and 11%, respectively. Moreover, the cytological results revealed a significant decrease in cell number along grain width direction and cell width in spikelet in mir5504, compared with those in NIP. In addition, several major storage substances of the rice seeds were measured. Compared to NIP, the amylose content of the mir5504 seeds was noticeably decreased, leading to an increase of nearly 10 mm in gel consistency (GC) in mir5504 lines. Further investigation confirmed that LOC_Os08g16914 was the genuine target of miR5504: LOC_Os08g16914 over-expression plants phenocopied the mir5504 mutants. This study provides insights into the role of miR5504 in rice seed development.


Assuntos
Grão Comestível , Regulação da Expressão Gênica de Plantas , MicroRNAs , Oryza , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Mutação , Pleiotropia Genética , Plantas Geneticamente Modificadas , RNA de Plantas/genética , RNA de Plantas/metabolismo , Amilose/metabolismo
7.
Antimicrob Agents Chemother ; 68(7): e0052424, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38899917

RESUMO

HRS9432(A) is a long-acting echinocandin antifungal medication primarily used to treat invasive fungal infections, particularly invasive candidiasis. The safety, tolerability, and pharmacokinetic characteristics of HRS9432(A) injection were investigated in a randomized, double-blind, placebo-controlled, single- and multiple-ascending-dose Phase I study involving 56 healthy adult subjects. Doses ranging from 200 to 1200 mg were administered. Safety was continually monitored, including adverse events, clinical laboratory examinations, vital signs, 12-lead electrocardiograms, and physical examinations, while the pharmacokinetic profile within the body was evaluated. The results indicated that concentrations of HRS9432 peaked immediately after infusion, demonstrating essentially linear pharmacokinetic characteristics within the dosage range of 200-1,200 mg. It exhibited a low clearance rate and an extended half-life, with a clearance of approximately 0.2 L/h, a volume of distribution of around 40 L, and a half-life of approximately 140h following a single dose. The accumulation index for AUC0-τ after multiple doses ranged from 1.41 to 1.75. No severe adverse events occurred during the study, and the severity of all adverse events was mild or moderate. Therefore, the intravenous administration of HRS9432(A) in healthy Chinese adult subjects, either as multiple infusions of 200 to 600 mg (once a week, four doses) or as a single infusion of 900-1,200 mg, demonstrated overall good safety and tolerability. The pharmacokinetic exhibited essentially linear characteristics in the body, supporting a weekly dosing frequency for clinical applications and providing additional options for the treatment or prevention of invasive fungal infections. CLINICAL TRIALS: This study is registered with the International Clinical Trials Registry Platform as ChiCTR2300073525.


Assuntos
Antifúngicos , Voluntários Saudáveis , Humanos , Método Duplo-Cego , Adulto , Masculino , Antifúngicos/farmacocinética , Antifúngicos/administração & dosagem , Antifúngicos/efeitos adversos , Feminino , Adulto Jovem , Meia-Vida , Área Sob a Curva , Micafungina/farmacocinética , Micafungina/administração & dosagem , Micafungina/efeitos adversos , Pessoa de Meia-Idade , Povo Asiático , População do Leste Asiático
8.
Anal Chem ; 96(21): 8249-8253, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38717298

RESUMO

Combinatorial electrochemistry has great promise for accelerated reaction screening, organic synthesis, and catalysis. Recently, we described a new high-throughput electrochemistry platform, colloquially named "Legion". Legion fits the footprint of a 96-well microtiter plate with simultaneous individual control over all 96 electrochemical cells. Here, we demonstrate the versatility of Legion when coupled with high-throughput mass spectrometry (MS) for electrosynthetic product screening and quantitation. Electrosynthesis of benzophenone azine was selected as a model reaction and was arrayed and optimized using a combination of Legion and nanoelectrospray ionization MS. The combination of high-throughput synthesis with Legion and analysis via MS proves a compelling strategy for accelerating reaction discovery and optimization in electro-organic synthesis.

9.
Radiology ; 310(3): e232605, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38530176

RESUMO

Background Detection of extranodal extension (ENE) at pathology is a poor prognostic indicator for rectal cancer, but whether ENE can be identified at pretreatment MRI is, to the knowledge of the authors, unknown. Purpose To evaluate the performance of pretreatment MRI in detecting ENE using a matched pathologic reference standard and to assess its prognostic value in patients with rectal cancer. Materials and Methods This single-center study included a prospective development data set consisting of participants with rectal adenocarcinoma who underwent pretreatment MRI and radical surgery (December 2021 to January 2023). MRI characteristics were identified by their association with ENE-positive nodes (χ2 test and multivariable logistic regression) and the performance of these MRI features was assessed (area under the receiver operating characteristic curve [AUC]). Interobserver agreement was assessed by Cohen κ coefficient. The prognostic value of ENE detected with MRI for predicting 3-year disease-free survival was assessed by Cox regression analysis in a retrospective independent validation cohort of patients with locally advanced rectal cancer (December 2019 to July 2020). Results The development data set included 147 participants (mean age, 62 years ± 11 [SD]; 87 male participants). The retrospective cohort included 110 patients (mean age, 60 years ± 9; 79 male participants). Presence of vessel interruption and fusion (both P < .001), heterogeneous internal structure, and the broken-ring and tail signs (odds ratio range, 4.10-23.20; P value range, <.001 to .002) were predictors of ENE at MRI, and together achieved an AUC of 0.91 (95% CI: 0.88, 0.93) in detecting ENE. Interobserver agreement was moderate for the presence of vessel interruption and fusion (κ = 0.46 for both) and substantial for others (κ = 0.61-0.67). The presence of ENE at pretreatment MRI was independently associated with worse 3-year disease-free survival (hazard ratio, 3.00; P = .02). Conclusion ENE can be detected at pretreatment MRI, and its presence was associated with worse prognosis for patients with rectal cancer. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Eberhardt in this issue.


Assuntos
Segunda Neoplasia Primária , Neoplasias Retais , Humanos , Masculino , Pessoa de Meia-Idade , Extensão Extranodal , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Neoplasias Retais/diagnóstico por imagem , Imageamento por Ressonância Magnética
10.
J Neuroinflammation ; 21(1): 153, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849869

RESUMO

Parkinson's disease (PD) is a prevalent neurodegenerative disorder with indistinct etiology and ill-defined pathophysiology. Intestinal inflammation involved in the pathogenesis of PD, but the underlying mechanism is not fully understood. Citrobacter rodentium (C.R) is a gram-negative bacterium that can be used to induce human inflammatory bowel disease in mice. Here, we investigated whether the proinflammatory effects caused by C.R infection initiate PD-like injury and/or exacerbate PD pathology and extensively studied the underlying mechanism. Mice were gavaged once with C.R and monitored for several pathological features at 9 days post infection. The results showed that C.R delivery in mice induced IBD-like symptoms, including significant weight loss, increased fecal water content, an impaired intestinal barrier, intestinal hyperpermeability and inflammation, and intestinal microbiota disturbances. Notably, C.R infection modified dopamine (DA) metabolism in the brains of both male and female mice. Subsequently, a single high dose of MPTP or normal saline was administered at 6 days post infection. At 3 days after MPTP administration, the feces were collected for 16 S rRNA analysis, and PD-like phenotypes and mechanisms were systemically analyzed. Compared with C.R or MPTP injection alone, the injection of C.R and MPTP combined worsened behavioral performance. Moreover, such combination triggered more severe dopaminergic degeneration and glial cell overactivation in the nigrostriatal pathway of mice. Mechanistically, the combination of C.R and MPTP increased the expression of TLR4 and NF-κB p65 in the colon and striatum and upregulated proinflammatory cytokine expression. Therefore, C.R infection-induced intestinal inflammation can impair dopamine metabolism and exacerbate PD pathological processes.


Assuntos
Citrobacter rodentium , Dopamina , Infecções por Enterobacteriaceae , Camundongos Endogâmicos C57BL , Animais , Camundongos , Dopamina/metabolismo , Infecções por Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/patologia , Masculino , Feminino , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doença de Parkinson/microbiologia , Microbioma Gastrointestinal/fisiologia
11.
Small ; : e2402402, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949051

RESUMO

Doping transition metal oxide spinels with metal ions represents a significant strategy for optimizing the electronic structure of electrocatalysts. Herein, a bimetallic Fe and Ru doping strategy to fine-tune the crystal structure of CoV2O4 spinel for highly enhanced oxygen evolution reaction (OER) is presented performance. The incorporation of Fe and Ru is observed at octahedral sites within the CoV2O4 structure, effectively modulating the electronic configuration of Co. Density functional theory calculations have confirmed that Fe acts as a novel reactive site, replacing V. Additionally, the synergistic effect of Fe, Co, and Ru effectively optimizes the Gibbs free energy of the intermediate species, reduces the reaction energy barrier, and accelerates the kinetics toward OER. As expected, the best-performing CoVFe0.5Ru0.5O4 displays a low overpotential of 240 mV (@10 mA cm-2) and a remarkably low Tafel slope of 38.9 mV dec-1, surpassing that of commercial RuO2. Moreover, it demonstrates outstanding long-term durability lasting for 72 h. This study provides valuable insights for the design of highly active polymetallic spinel electrocatalysts for energy conversion applications.

12.
J Transl Med ; 22(1): 264, 2024 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462601

RESUMO

BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) is a type of chronic interstitial pneumonia, often fatal, with elusive causes and a bleak prognosis. Its treatment options are limited and largely ineffective. Early detection and precise diagnosis are pivotal in managing the disease effectively and enhancing patient survival rates. Recently, the quest for trustworthy biomarkers for IPF has gained momentum. Notably, emerging studies indicate that circular RNAs (circRNAs) found in exosomes may hold significant potential as valuable diagnostic markers. METHODS: In this study, we initially explored the expression profile of circRNAs in exosomes sourced from the blood of IPF patients and healthy volunteers, employing a human circRNA microarray. We then utilized RT-qPCR to corroborate the dysregulated circRNAs identified by the microarray during the training phase. Next, the circRNAs that displayed a significant increase during the training phase were selected for further validation in a larger cohort encompassing 113 IPF patients and 76 healthy volunteers. Ultimately, the expression level and function of hsa_circ_0044226 were substantiated through a series of in vivo and in vitro experiments. RESULTS: Utilizing a human circRNA microarray, we identified 11 dysregulated circRNAs in the exosomes derived from the blood of IPF patients and control volunteers. Subsequent RT-qPCR analysis revealed significant increases in three circRNAs (hsa_circ_0044226, hsa_circ_0004099, hsa_circ_0008898) within the IPF patients. Notably, hsa_circ_0044226 was markedly elevated in patients experiencing acute exacerbation of IPF (AE-IPF) compared to those with stable IPF (S-IPF). Additionally, an upregulation of hsa_circ_0044226 was observed in the blood exosomes derived from a bleomycin-induced IPF mouse model. CONCLUSION: The expression levels of hsa_circ_0044226, hsa_circ_0004099, and hsa_circ_0008898 in plasma exosomes introduce a new paradigm of biomarkers for the diagnosis and progression of IPF.


Assuntos
Fibrose Pulmonar Idiopática , RNA Circular , Animais , Camundongos , Humanos , RNA Circular/genética , Biomarcadores , Prognóstico , Regulação para Cima , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/genética
13.
Appl Environ Microbiol ; 90(5): e0197423, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38619269

RESUMO

17ß-estradiol (E2) is a natural endocrine disruptor that is frequently detected in surface and groundwater sources, thereby threatening ecosystems and human health. The newly isolated E2-degrading strain Sphingomonas colocasiae C3-2 can degrade E2 through both the 4,5-seco pathway and the 9,10-seco pathway; the former is the primary pathway supporting the growth of this strain and the latter is a branching pathway. The novel gene cluster ean was found to be responsible for E2 degradation through the 4,5-seco pathway, where E2 is converted to estrone (E1) by EanA, which belongs to the short-chain dehydrogenases/reductases (SDR) superfamily. A three-component oxygenase system (including the P450 monooxygenase EanB1, the small iron-sulfur protein ferredoxin EanB2, and the ferredoxin reductase EanB3) was responsible for hydroxylating E1 to 4-hydroxyestrone (4-OH-E1). The enzymatic assay showed that the proportion of the three components is critical for its function. The dioxygenase EanC catalyzes ring A cleavage of 4-OH-E1, and the oxidoreductase EanD is responsible for the decarboxylation of the ring A-cleavage product of 4-OH-E1. EanR, a TetR family transcriptional regulator, acts as a transcriptional repressor of the ean cluster. The ean cluster was also found in other reported E2-degrading sphingomonads. In addition, the novel two-component monooxygenase EanE1E2 can open ring B of 4-OH-E1 via the 9,10-seco pathway, but its encoding genes are not located within the ean cluster. These results refine research on genes involved in E2 degradation and enrich the understanding of the cleavages of ring A and ring B of E2.IMPORTANCESteroid estrogens have been detected in diverse environments, ranging from oceans and rivers to soils and groundwater, posing serious risks to both human health and ecological safety. The United States National Toxicology Program and the World Health Organization have both classified estrogens as Group 1 carcinogens. Several model organisms (proteobacteria) have established the 4,5-seco pathway for estrogen degradation. In this study, the newly isolated Sphingomonas colocasiae C3-2 could degrade E2 through both the 4,5-seco pathway and the 9,10-seco pathway. The novel gene cluster ean (including eanA, eanB1, eanC, and eanD) responsible for E2 degradation by the 4,5-seco pathway was identified; the novel two-component monooxygenase EanE1E2 can open ring B of 4-OH-E1 through the 9,10-seco pathway. The TetR family transcriptional regulator EanR acts as a transcriptional repressor of the ean cluster. The cluster ean was also found to be present in other reported E2-degrading sphingomonads, indicating the ubiquity of the E2 metabolism in the environment.


Assuntos
Biodegradação Ambiental , Estradiol , Família Multigênica , Sphingomonas , Sphingomonas/metabolismo , Sphingomonas/genética , Estradiol/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Disruptores Endócrinos/metabolismo , Filogenia
14.
Opt Express ; 32(5): 8425-8436, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38439498

RESUMO

Glutathione (GSH) plays vital role in human biological systems, so its rapid and sensitive detection is necessary for health condition monitoring. In this work, a simple structure for dual channel GSH and refractive index (RI) detection is proposed. By introducing Au-MnO2 thin film coating on the fiber surface for the first time, GSH solution would lead to the dissolution of MnO2, the change in GSH levels could be monitored over a short period in channel 2. For channel 1, ITO-Ag thin film is applied for RI change detection. After optimization, the GSH detection sensitivity reached about -2.361 nm/mM in the range of 0.005-50 mM, and the RI sensitivity reached 1704.252 nm/RIU in the range of 1.331-1.3895 RIU. Channel 1 could also put into GSH detection in the high concentration scale to enlarge the sensor's range and 0.095 nm/mM of sensitivity is acquired within the range of 50-600 mM. With the presence of MnO2 film, the detection sensitivity increased 25.663 times. Neither channel interferes with the operation of the other. Proposed sensor provides stability, high selectivity and elevation in GSH detection sensitivity, which shows great potential for environmental and biological detection field and their applications.

15.
Opt Express ; 32(8): 14521-14531, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859394

RESUMO

A topological photonic crystal InGaAsP/InP core-shell nanowire array laser with bulk states operating in the 1550 nm band is proposed and simulated. By optimizing the structure parameters, high Q factor of 1.2 × 105 and side-mode suppression ratio of 13.2 dB are obtained, which are 28.6 and 4.6 times that of a uniform nanowire array, respectively. The threshold and maximum output are 17% lower and 613% higher than that of the uniform nanowire array laser, respectively, due to the narrower nanowire slits and stronger optical confinement. In addition, a low beam divergence angle of 2° is obtained due to the topological protection. This work may pave the way for the development of high-output, low-threshold, low-beam-divergence nanolasers.

16.
Opt Express ; 32(1): 652-661, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175089

RESUMO

A Si-based nanowire array photonic-crystal surface-emitting laser based on a flat band is designed and simulated. By introducing an air gap between the nanowire and substrate, the bottom reflectivity is significantly enhanced, resulting in much lower threshold and smaller cutoff diameter. Through adjusting the lattice constant (the distance between neighboring nanowires) and nanowire diameter, a photonic crystal structure with a flat band is achieved, in which strong interaction between light and matter occurs in the flat band mode. For the device with a small size, single-mode lasing is obtained with a side-mode suppression ratio of 21 dB, high quality factor of 3940, low threshold gain of 624 cm-1, and small beam divergency angle of ∼7.5°. This work may pave the way for the development of high-performance Si-based surface-emitting nanolasers and high-density photonic integrated circuits.

17.
Opt Express ; 32(2): 1295-1304, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297684

RESUMO

The combined application of metasurface and terahertz (THz) time-domain spectroscopy techniques has received considerable attention in the fields of sensing and detection. However, to detect trace samples, the THz wave must still be enhanced locally using certain methods to improve the detection sensitivity. In this study, we proposed and experimentally demonstrated a fano resonance metasurface-based silver nanoparticles (FaMs-AgNPs) sensor. AgNPs can enhance the sensitivity of the sensor by generating charge accumulation and inducing localized electric field enhancement through the tip effect, thereby enhancing the interaction between the THz waves and analytes. We investigated the effects of four different contents of AgNPs, 10 µl, 20 µl, 30 µl and 40 µl, on the detection of acetamiprid. At 30 µl of AgNPs, the amplitude change of the FaMs-AgNPs sensor was more pronounced and the sensitivity was higher, which could detect acetamiprid solutions as low as 100 pg/ml. The FaMs-AgNPs sensor has the advantages of a simple structure, easy processing, and excellent sensing performance, and has a great potential application value in the field of THz trace detection and other fields.

18.
Opt Lett ; 49(11): 3190-3193, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824360

RESUMO

In this study, multi-wavelength second-harmonic generation (SHG) based on self-phase modulation (SPM) broadband supercontinuum (SC) was observed by employing a double-clad high nonlinear optical fiber (HNLF) in conjunction with a femtosecond laser. At a wavelength of 1050 nm and an average pump power of 320 mW, multiple phase-matching conditions were achieved, and SH signals of central wavelengths ∼530.7 nm, ∼525.1 nm, ∼503.5 nm, and ∼478.7 nm were observed, with SHG efficiency reaching ∼1.34 × 10-4. The SHG in this experiment can be attributed to the utilization of a doped optical fiber, where dopants create defect states, facilitating optical-chemical transformation and enhancing second-order polarization susceptibility. Additionally, theoretical simulations were conducted, aligning closely with the experimental findings. To the best of our knowledge, this work marks the first demonstration of multi-wavelength SHG in optical fibers. It offers a distinctive avenue for customizing multi-wavelength ultrafast light sources, exhibiting great application potential in the fields of medical diagnostics and optical sensing.

19.
Diabetes Metab Res Rev ; 40(4): e3814, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38769695

RESUMO

AIMS: This study aimed to evaluate the association between gestational diabetes mellitus (GDM) and circulating folate metabolites, folic acid (FA) intake, and the methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) genotype. MATERIALS AND METHODS: A prospective pregnancy cohort study was conducted in Beijing, China, from 2022 to 2023. Circulating folate metabolites, including red blood cell (RBC) 5-methyltetrahydrofolate (5-MTHF), 5, 10-methylene-tetrahydrofolate (5,10-CH2-THF), 5- formyltetrahydrofolate (5-CHO-THF), and unmetabolised folic acid (UMFA), and plasma homocysteine (HCY), 5-MTHF, and methylmalonic acid (MMA), were determined at 6-17 weeks and 20-26 weeks of gestation. FA intake and the MTHFR and MTRR genotype were also examined. GDM was diagnosed between 24 and 28 weeks of pregnancy by a 75-g oral glucose tolerance test (OGTT). The association between the folate status and GDM was ascertained using multivariate generalised linear models, logistic regression models, and restricted cubic spline regression, adjusting for potential confounders. RESULTS: The study included 2032 pregnant women, of whom 392 (19.29%) developed GDM. UMFA above the 75th percentile (≥P75) [adjusted OR (aOR) (95% confidence interval [CI]) = 1.36 (1.01-1.84)], UMFA ≥ P90 [aOR (95% CI) = 1.82 (1.23-2.69)], and HCY ≥ P75 [aOR (95% CI) = 1.40 (1.04-1.88)] in early pregnancy, and RBC 5-MTHF [aOR (95% CI) = 1.48 (1.10-2.00)], RBC 5,10-CH2-THF [aOR (95% CI) = 1.55 (1.15-2.10)], and plasma 5-MTHF [aOR (95% CI) = 1.36 (1.00-1.86)] in mid-pregnancy ≥ P75 are associated with GDM. Higher UMFA levels in early pregnancy show positive associations with the 1-h and 2-h glucose levels during the OGTT, and higher HCY levels are associated with increased fasting glucose levels during the OGTT. In comparison, RBC 5- MTHF and 5,10-CH2-THF, and plasma 5- MTHF in mid-pregnancy are positively associated with the 1-h glucose level (p < 0.05). The MTHFR and MTRR genotype and FA intake are not associated with GDM. CONCLUSIONS: Elevated levels of UMFA and HCY during early pregnancy, along with elevated RBC 5-MTHF and 5,10-CH2-THF and plasma 5-MTHF during mid-pregnancy, are associated with GDM. These findings indicate distinct connections between different folate metabolites and the occurrence of GDM.


Assuntos
Diabetes Gestacional , Ácido Fólico , Metilenotetra-Hidrofolato Redutase (NADPH2) , Humanos , Feminino , Diabetes Gestacional/sangue , Diabetes Gestacional/metabolismo , Gravidez , Ácido Fólico/sangue , Estudos Prospectivos , Adulto , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Biomarcadores/sangue , Seguimentos , Ferredoxina-NADP Redutase/genética , Genótipo , China/epidemiologia , Prognóstico , Segundo Trimestre da Gravidez/sangue , Homocisteína/sangue , Homocisteína/metabolismo
20.
Anticancer Drugs ; 35(7): 658-665, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38718261

RESUMO

Currently, although some antibody-drug conjugates have been shown to be safe and effective in the treatment of drug-resistant relapsed human epidermal growth factor receptor 2 (HER2)-positive (IHC 3+ or IHC 2+/fluorescence in situ hybridization+) breast cancer, they are already approved for clinical use in China. But the clinical needs of advanced HER2-positive patients cannot be met due to adverse reactions, drug resistance, drug accessibility and other problems, thus affecting the prognosis of patients. In particular, the representation of elderly and frail patients in randomized clinical trials is significantly under-represented. We report on two elderly women with breast cancer who developed recurrent metastatic lesions after breast cancer surgery and were again confirmed HER2-positive by histopathology and immunohistochemistry. They all developed multiple metastases in the liver after second- or third-line anti-HER2 therapy. Subsequent treatment with RC48 produced good responses and tolerable adverse reactions. One patient obtained progression-free survival for more than 7 months. Based on preliminary evidence, this study shows that RC48 in HER2-positive breast cancer with liver metastases can achieve rapid remission, thereby reducing tumor load and improving patients' quality of life. In particular, RC48 has low side effects and can be well tolerated by elderly patients after dose adjustment, providing them with treatment opportunities. It needs to be further discussed in the future research.


Assuntos
Neoplasias da Mama , Neoplasias Hepáticas , Receptor ErbB-2 , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Receptor ErbB-2/metabolismo , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Imunoconjugados/administração & dosagem , Imunoconjugados/uso terapêutico
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