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1.
Zookeys ; 1197: 43-55, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38616923

RESUMO

Due to the detrimental effect of formaldehyde on DNA, ethanol has replaced formalin as the primary preservative for animal specimens. However, short-term formalin fixation of specimens might be applied during field collection. In an increasing number of studies, DNA extraction and sequencing have been successfully conducted from formalin-fixed specimens. Here the DNA from five specimens of Triplophysadalaica (Kessler, 1876) were extracted and performed high-throughput sequencing. Four of the specimens underwent short-term fixation with formalin and were subsequently transferred to ethanol. One was continuously stored in ethanol. No significant difference of DNA quality and amount were observed among these samples. Followed by assembly and annotation, five mitochondrial genomes ranging in length from 16,569 to 16,572 bp were obtained. Additionally, previously published data of other individuals or species were included to perform phylogenetic analyses. In the reconstructed trees, all eight individuals of T.dalaica form a monophyletic group within the Triplophysa branch. The group is divided into three clades: (1) samples from the Yellow River, (2) those from the Yangtze River, and (3) those from the Haihe River, and the Lake Dali Nur. This study sheds initial light on the phylogeographic relationships among different populations of T.dalaica, and will support the research about its evolutionary history in the future.

2.
RSC Adv ; 14(17): 11771-11774, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38617572

RESUMO

There have been scarce reports about stereoscopic design of N-heteroacenes (NHAs), especially for the electron-deficient π-building blocks. Herein, we report the design and synthesis of a U-shaped bis(pyrene-quinoxaline) (BPQ). Single crystal X-ray diffraction reveals the herringbone stacking pattern and the presence of regular and incompletely closed pores.

3.
Pharmacol Rev ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622001

RESUMO

In the era of precision medicine, Antibody-Drug Conjugates (ADCs) have emerged as a cutting-edge therapeutic strategy. These innovative compounds combine the precision of monoclonal antibodies with the potent cell-killing or immune-modulating abilities of attached drug payloads. This unique strategy not only reduces off-target toxicity but also enhances the therapeutic effectiveness of drugs. Beyond their well-established role in oncology, ADCs are now showing promising potential in addressing the unmet needs in the therapeutics of rheumatic diseases. Rheumatic diseases, a diverse group of chronic autoimmune diseases with varying etiologies, clinical presentations, and prognoses, often demand prolonged pharmacological interventions, creating a pressing need for novel, efficient and low-risk treatment options. ADCs, with their ability to precisely target the immune components, have emerged as a novel therapeutic strategy in this context. This review will provide an overview of the core components and mechanisms behind ADCs, a summary of the latest clinical trials of ADCs for the treatment if rheumatic diseases, as well as a discussion on the challenges and future prospects faced by the development of next-generation ADCs. Significance Statement There is a lack of efficient and low-risk targeted therapeutics for rheumatic diseases. Antibody-drug conjugates, a class of cutting-edge therapeutic drugs, have emerged as a promising targeted therapeutic strategy for rheumatic disease. While there is limited literature summarizing the progress of antibody-drug conjugates in the field of rheumatic disease, updating the advancements in this area provides novel insights into the development of novel anti-rheumatic drugs.

4.
Org Biomol Chem ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623862

RESUMO

Asp-based lactam cyclic peptides are considered promising drug candidates. However, using Fmoc solid-phase peptide synthesis (Fmoc-SPPS) for these peptides also causes aspartimide formation, resulting in low yields or even failure to obtain the target peptides. Here, we developed a diaminodiacid containing an amide bond as a ß-carboxyl-protecting group for Asp to avoid aspartimide formation. The practicality of this diaminodiacid has been illustrated by the synthesis of lactam cyclic peptide cyclo[Lys9,Asp13] KIIIA7-14 and 1Y.

5.
BMC Pulm Med ; 24(1): 179, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622599

RESUMO

BACKGROUND: Anti-synthetase syndrome (AS) is a rare autoimmune idiopathic inflammatory myopathy (IIM) with diverse manifestations, including arthritis, interstitial lung disease (ILD), Raynaud's phenomenon, unexplained persistent fever, and mechanic's hands. CASE PRESENTATION: We present the case of a 72-year-old woman, previously healthy, who was admitted to our hospital for treatment of cough and rapid breathing. The patient had elevated white blood cells and C-reactive protein, and tested negative for severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2). She was initially diagnosed with community-acquired pneumonia and received tamoxifen for anti-infection treatment, but her dystonia worsened. She eventually required non-invasive ventilator support, tested positive for SARS-Cov-2 again, and started antiviral therapy, corticosteroids to reduce alveolar effusion, anticoagulation, and other treatments. However, her condition continued to deteriorate, with the lowest oxygenation index reaching only 80mmHg. Ultimately, she underwent tracheal intubation and mechanical ventilation. Chest CT revealed rapid progressive interstitial changes in her lungs, and her hands showed noticeable fraternization changes. At this point, we suspected that the novel coronavirus infection might be associated with autoimmune diseases. The patient's autoimmune antibody spectrum showed positive results for anti-recombinant RO-52 antibody and myositis-specific antibody anti-alanyl tRNA synthetase (anti-PL-12). The patient was treated with dexamethasone sodium phosphate for anti-inflammatory and anti-fibrotic effects. After successful extubation, the patient was discharged with only oral prednisone tablets at a dose of 30 mg. CONCLUSIONS: This case presents an early diagnosis and successful treatment of anti-synthetase syndrome combined with SARS-Cov-2 infection, emphasizing the importance of comprehensive physical examination. Additionally, it highlights the rapid progression of interstitial lung disease under SARS-Cov-2 infection, which is often difficult to distinguish on imaging. In cases where treatment for SARS-Cov-2 infection is ineffective, early screening for autoimmune diseases is recommended. As there is currently no standardized method for treating AS-ILD, the successful treatment of this case provides a reference for clinical research on anti-synthetase syndrome in the later stage.


Assuntos
Doenças Autoimunes , COVID-19 , Doenças Pulmonares Intersticiais , Miosite , Humanos , Feminino , Idoso , COVID-19/complicações , SARS-CoV-2 , Miosite/complicações , Miosite/diagnóstico , Miosite/tratamento farmacológico , Doenças Pulmonares Intersticiais/complicações , Doenças Pulmonares Intersticiais/diagnóstico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Autoimunes/complicações , Autoanticorpos
6.
Cytojournal ; 21: 12, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628288

RESUMO

Objective: This study aimed to identify differential metabolites and key metabolic pathways between lung adenocarcinoma (LUAD) tissues and normal lung (NL) tissues using metabolomics techniques, to discover potential biomarkers for the early diagnosis of lung cancer. Material and Methods: Forty-five patients with primary ground-glass nodules (GGN) identified on computed tomography imaging and who were willing to undergo surgery at Shanghai General Hospital from December 2021 to December 2022 were recruited to the study. All participants underwent video thoracoscopy surgery with segmental or wedge resection of the lung. Tissue samples for pathological examination were collected from the site of ground-glass nodules (GGN) lesion and 3 cm away from the lesion (NL). The pathology results were 35 lung adenocarcinoma (LUAD) cases (13 invasive adenocarcinoma, 14 minimally invasive adenocarcinoma, and eight adenocarcinoma in situ), 10 benign samples, and 45 NL tissues. For the untargeted metabolomics technique, 25 LUAD samples were assigned as the case group and 30 NL tissues as the control group. For the targeted metabolomics technique, ten LUAD samples were assigned as the case group and 15 NL tissues as the control group. Samples were analyzed by untargeted and targeted metabolomics, with liquid chromatography-tandem mass spectrometry detection used as part of the experimental procedure. Results: Untargeted metabolomics revealed 164 differential metabolites between the case and control groups, comprising 110 up regulations and 54 down regulations. The main metabolic differences found by the untargeted method were organic acids and their derivatives. Targeted metabolomics revealed 77 differential metabolites between the case and control groups, comprising 69 up regulations and eight down regulations. The main metabolic changes found by the targeted method were fatty acids, amino acids, and organic acids. The levels of organic acids such as lactic acid, fumaric acid, and malic acid were significantly increased in LUAD tissue compared to NL. Specifically, an increased level of L-lactic acid was found by both untargeted (variable importance in projection [VIP] = 1.332, fold-change [FC] = 1.678, q = 0.000) and targeted metabolomics (VIP = 1.240, FC = 1.451, q = 0.043). Targeted metabolomics also revealed increased levels of fumaric acid (VIP = 1.481, FC = 1.764, q = 0.106) and L-malic acid (VIP = 1.376, FC = 1.562, q = 0.012). Most of the 20 differential fatty acids identified were downregulated, including dodecanoic acid (VIP = 1.416, FC = 0.378, q = 0.043) and tridecane acid (VIP = 0.880, FC = 0.780, q = 0.106). Furthermore, increased levels of differential amino acids were found in LUAD samples. Conclusion: Lung cancer is a complex and heterogeneous disease with diverse genetic alterations. The study of metabolic profiles is a promising research field in this cancer type. Targeted and untargeted metabolomics revealed significant differences in metabolites between LUAD and NL tissues, including elevated levels of organic acids, decreased levels of fatty acids, and increased levels of amino acids. These metabolic features provide valuable insights into LUAD pathogenesis and can potentially serve as biomarkers for prognosis and therapy response.

7.
Int Immunopharmacol ; 133: 112040, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38631220

RESUMO

BACKGROUND: Ankylosing spondylitis (AS) is a chronic autoimmune arthritis that mainly affects spine joints. To date, the pathogenesis of AS remains unclear, although immune cells and innate immune response cytokines have been suggested to be crucial players. METHODS: By adopting a single-cell RNA sequencing approach in the AS cynomolgus model, we profiled and characterized PBMC proportions along disease progression. RESULTS: Here, our primary focus was on the activation of an immune cascade-initiating lymphocyte subtype known as CD4+CXCR5+ T follicular helper (Tfh) cells. These Tfhs demonstrated a localized residence in AS bone lesion as an ectopic lymphoid structure. Moreover, Tfhs would serve as an upstream initiator for a pro-angiogenic cascade. Then, an expansion in CD14+ monocytes and DC cells subsets resulted in enhanced expression of angiogenesis genes in these AS cynomolgus monkeys. With a confirmed higher abundance of TNF-α accompanying H-type vascular invasion in the osteophytic region, pronounced expansion of Tfhs at such lesion site signaling for monocytes and DCs intrusion is considered as the prelude to the characteristic angiogenic bony outgrowth in AS known as syndesmophytes. CONCLUSIONS: We explored the intimate relationship between local inflammation and bone formation in AS from the perspective of nascent vascularisation. Hence, our study lays the foundation for elucidating a unified AS pathogenesis through the immune-angiogenesis-osteogenesis axis.

8.
Biochem Genet ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609670

RESUMO

The polycystic ovary syndrome (PCOS), a common endocrine disorder, is mainly related to infertility. Moreover, it is characterized by promoted androgen, suppressed ovulation and insulin resistance. Long non-coding RNA X inactive specific transcript (lncRNA XIST), known as an oncogene or a cancer inhabited factor, is involved in several disease. However, the diagnostic mechanisms of lncRNA XIST in PCOS have not been clarified. Our study aimed to explain whether lncRNA XIST regulates KGN cells proliferation and apoptosis via microRNA (miR)-212-3p/RASA1 axis in PCOS. Levels of lncRNA XIST, miR-212-3p and RASA1 in KGN cells were detected through reverse transcription quantitative polymerase chain reaction (RT-qPCR) assay. Fluorescence in situ Hybridization (FISH) was performed to confirm the expression of lncRNA XIST and miR-212-3p in KGN cells. StarBase and dual-luciferase reporter assay were applied for exploring the interaction between miR-212-3p and RASA1. Cell viability, apoptosis, protein expression of Bcl-2 and Bax were assessed by MTT, flow cytometry analysis, RT-qPCR and western blot, respectively. We found that lncRNA XIST was low-expressed, miR-212-3p was over-expressed, and RASA1 was dramatically down-regulated in KGN cells. LncRNA XIST negatively regulated miR-212-3p expression in KGN cells. MiR-212-3p interacted with RASA1 and negatively regulated RASA1 levels in KGN cells. Up-regulation of lncRNA XIST signally decreased cells viability, stimulated more apoptotic cells, enhanced Bax expression, and depressed Bcl-2 level in KGN cells. However, these observations were abolished after miR-212-3p mimic treatment. Furthermore, miR-212-3p inhibitor significantly inhibited cell proliferation, enhanced more apoptotic cells, increased Bax expression, and decreased Bcl-2 level in KGN cells, and these effects were eliminated by RASA1-siRNA transfection. Our observations revealed that lncRNA XIST protects against PCOS through regulating miR-212-3p/RASA1 axis, suggesting that lncRNA XIST may be a promising therapeutic target for PCOS therapy.

9.
Yeast ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38613186

RESUMO

Engineering Yarrowia lipolytica to produce astaxanthin provides a promising route. Here, Y. lipolytica M2 producing a titer of 181 mg/L astaxanthin was isolated by iterative atmospheric and room-temperature plasma mutagenesis and diphenylamine-mediated screening. Interestingly, a negative correlation was observed between cell biomass and astaxanthin production. To reveal the underlying mechanism, RNA-seq analysis of transcriptional changes was performed in high producer M2 and reference strain M1, and a total of 1379 differentially expressed genes were obtained. Data analysis revealed that carbon flux was elevated through lipid metabolism, acetyl-CoA and mevalonate supply, but restrained through central carbon metabolism in strain M2. Moreover, upregulation of other pathways such as ATP-binding cassette transporter and thiamine pyrophosphate possibly provided more cofactors for carotenoid hydroxylase and relieved cell membrane stress caused by astaxanthin insertion. These results suggest that balancing cell growth and astaxanthin production may be important to promote efficient biosynthesis of astaxanthin in Y. lipolytica.

10.
Infection ; 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613657

RESUMO

BACKGROUND: The global mortality rate resulting from HIV-associated cryptococcal disease is remarkably elevated, particularly in severe cases with dissemination to the lungs and central nervous system (CNS). Regrettably, there is a dearth of predictive analysis regarding long-term survival, and few studies have conducted longitudinal follow-up assessments for comparing anti-HIV and antifungal treatments. METHODS: A cohort of 83 patients with HIV-related disseminated cryptococcosis involving the lung and CNS was studied for 3 years to examine survival. Comparative analysis of clinical and immunological parameters was performed between deceased and surviving individuals. Subsequently, multivariate Cox regression models were utilized to validate mortality predictions at 12, 24, and 36 months. RESULTS: Observed plasma cytokine levels before treatment were significantly lower for IL-1RA (p < 0.001) and MCP-1 (p < 0.05) when in the survivor group. Incorporating plasma levels of IL-1RA, IL-6, and high-risk CURB-65 score demonstrated the highest area under curve (AUC) value (0.96) for predicting 1-year mortality. For 1-, 2- and 3-year predictions, the single-factor model with IL-1RA demonstrated superior performance compared to all multiple-variate models (AUC = 0.95/0.78/0.78). CONCLUSIONS: IL-1RA is a biomarker for predicting 3-year survival. Further investigations to explore the pathogenetic role of IL-1RA in HIV-associated disseminated cryptococcosis and as a potential therapeutic target are warranted.

11.
J Asian Nat Prod Res ; : 1-8, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619479

RESUMO

Alzheimer's disease is a neurodegenerative disorder characterized by the presence of neurodegenerative lesions and cognitive impairment. In this study, a series of novel palmatine derivatives were designed and synthesized through the introduction of a heteroatom using carbodiimide-mediated condensation. The synthesized compounds were then screened for toxicity and potency, leading to the identification of compound 2q, which exhibited low toxicity and high potency. Our findings demonstrated that compound 2q displayed significant neuroprotective activity in vitro, emerging as a promising candidate for Alzheimer's disease treatment.

12.
Cancer Nurs ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38625787

RESUMO

BACKGROUND: Physical activity promotes healthy physical and mental development in children with leukemia. However, the level of physical activity in hospitalized children with leukemia and the factors that influence it are unknown. OBJECTIVES: The aims of this study were to understand the physical activity level of hospitalized children with leukemia and to explore the factors influencing it to provide a reference for physical activity assessment and intervention in such children. METHODS: A total of 133 hospitalized children with leukemia completed a general information questionnaire, the Chinese University of Hong Kong Physical Activity Rating for Children and Youth, and the Children's Social Anxiety Scale. A cross-sectional study was used to explore the effects of different variables on the children's activity levels. RESULTS: Among the study participants, 44.4% had a low-intensity activity level, 35.3% had a moderate-intensity activity level, and 20.3% had a high-intensity activity level, with a total physical activity rating of 3 (1, 6). Chemotherapy phase (P = .007), screen time (P = .001), and social anxiety (P = .012) were identified as influential factors. CONCLUSIONS: Our results showed that children with hospitalized leukemia had lower-intensity physical activity levels, especially in the chemotherapy phase of induction remission. Furthermore, screen time and social anxiety had negative effects on the children's activity levels. IMPLICATIONS FOR PRACTICE: According to the physical activity level of the children and the influencing factors, healthcare professionals should gradually improve children's mobility and promote their physical and mental health development through guidance and encouragement, and the development of personalized activity intervention programs.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38626346

RESUMO

Background: The incidence of chronic obstructive pulmonary disease (COPD) and osteoporosis are rising worldwide. Observational studies showed that COPD is associated with increased risk of osteoporosis. We performed the Mendelian randomization (MR) study to genetically investigate the causality of COPD on osteoporosis. Methods: We explored the causal effect of COPD on osteoporosis by the MR analysis. A total of 108 genetic loci single nucleotide polymorphisms were related to COPD. The primary approach in this MR analysis was the inverse variance-weighted (IVW) method. Simple median, weighted median, MR Egger and penalized weighted median analyzed the sensitivity. Results: The study found that genetically predicted COPD is causally linked to an increased risk of osteoporosis, as evidenced by both the fixed-effect IVW model and random-effect IVW model (odds ratio [OR], 1.010; 95% CI, 1.001-1.019, P=0.021; OR, 1.010; 95% CI, 1.001-1.020, P=0.039). This association was also observed in other methods, including the simple median, weighted median, Penalised weighted median, MR-Egger method, and MR Egger (bootstrap) method. The results of the IVW and MR-Egger analyses showed no heterogeneity (Q=131.374, P=0.061 and Q=128.895, P=0.069, respectively). Additionally, MR-Egger regression did not reveal any pleiotropic influence through genetic variants (intercept, -0.004; P=0.101). Lastly, the leave-one-out sensitivity analysis did not identify any individual SNP that significantly influenced the association between COPD and osteoporosis. Conclusion: The Mendelian randomization analysis showed a significant detrimental effect of COPD on the risk of osteoporosis.

14.
Adv Sci (Weinh) ; : e2310295, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626370

RESUMO

Neuropathic pain can occur during the prediabetic stage, even in the absence of hyperglycemia. The presence of prediabetic neuropathic pain (PDNP) poses challenges to the management of individuals with prediabetes. However, the mechanisms underlying this pain remain unclear. This study aims to investigate the underlying mechanism and identify potential therapeutic targets of PDNP. A prediabetic animal model induced by a high-energy diet exhibits both mechanical allodynia and thermal hyperalgesia. Furthermore, hyperexcitability and decreased potassium currents are observed in the dorsal root ganglion (DRG) neurons of these rats. TREK1 and TREK2 channels, which belong to the two-pore-domain K+ channel (K2P) family and play an important role in controlling cellular excitability, are downregulated in DRG neurons. Moreover, this alteration is modulated by Sortilin, a molecular partner that modulates the expression of TREK1. The overexpression of Sortilin negatively affects the expression of TREK1 and TREK2, leading to increased neuronal excitability in the DRG and enhanced peripheral pain sensitivity in rats. Moreover, the downregulation of Sortilin or activation of TREK1 and TREK2 channels by genetic or pharmacological approaches can alleviate PDNP. Therefore, targeting the Sortilin-mediated TREK1/2 pathway may provide a therapeutic approach for ameliorating PDNP.

15.
Acta Pharmacol Sin ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627462

RESUMO

Despite the effectiveness of antiretroviral therapy (ART) in prolonging the lifespan of individuals infected with HIV-1, it does not offer a cure for acquired immunodeficiency syndrome (AIDS). The "block and lock" approach aims to maintain the provirus in a state of extended transcriptional arrest. By employing the "block and lock" strategy, researchers endeavor to impede disease progression by preventing viral rebound for an extended duration following patient stops receiving ART. The crux of this strategy lies in the utilization of latency-promoting agents (LPAs) that are suitable for impeding HIV-1 provirus transcription. However, previously documented LPAs exhibited limited efficacy in primary cells or samples obtained from patients, underscoring the significance of identifying novel LPAs that yield substantial outcomes. In this study, we performed high-throughput screening of FDA-approved compound library in the J-Lat A2 cell line to discover more efficacious LPAs. We discovered ripretinib being an LPA candidate, which was validated and observed to hinder proviral activation in cell models harboring latent infections, as well as CD4+ T cells derived from infected patients. We demonstrated that ripretinib effectively impeded proviral activation through inhibition of the PI3K-AKT-mTOR signaling pathway in the HIV-1 latent cells, thereby suppressing the opening states of cellular chromatin. The results of this research offer a promising drug candidate for the implementation of the "block and lock" strategy in the pursuit of an HIV-1 cure.

18.
J Am Heart Assoc ; 13(8): e031578, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38563379

RESUMO

BACKGROUND: In 2009, a workplace-based hypertension management program was launched among men with hypertension in the Kailuan study. This program involved monitoring blood pressure semimonthly, providing free antihypertensive medications, and offering personalized health consultations. However, the cost-effectiveness of this program remains unclear. METHODS AND RESULTS: This analysis included 12 240 participants, with 6120 in each of the management and control groups. Using a microsimulation model derived from 10-year follow-up data, we estimated costs, quality-adjusted life years (QALYs), life-years, and incremental cost-effectiveness ratios (ICERs) for workplace-based management compared with routine care in both the study period and over a lifetime. Analyses are conducted from the societal perspective. Over the 10-year follow-up, patients in the management group experienced an average gain of 0.06 QALYs with associated incremental costs of $633.17 (4366.85 RMB). Projecting over a lifetime, the management group was estimated to increase by 0.88 QALYs or 0.92 life-years compared with the control group, with an incremental cost of $1638.64 (11 301.37 RMB). This results in an incremental cost-effectiveness ratio of $1855.47 per QALY gained and $1780.27 per life-year gained, respectively, when comparing workplace-based management with routine care. In probabilistic sensitivity analyses, with a threshold willingness-to-pay of $30 765 per QALY (3 times 2019 gross domestic product per capita), the management group showed a 100% likelihood of being cost-effective in 10 000 samples. CONCLUSIONS: Workplace-based management, compared with routine care for Chinese men with hypertension, could be cost-effective both during the study period and over a lifetime, and might be considered in working populations in China and elsewhere.


Assuntos
Hipertensão , Masculino , Humanos , Análise Custo-Benefício , Hipertensão/tratamento farmacológico , Anti-Hipertensivos/uso terapêutico , Local de Trabalho , China/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida
19.
ACS Appl Mater Interfaces ; 16(15): 19048-19056, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578807

RESUMO

The intrinsic low electrical properties have hindered the enhancement of thermoelectric performance for n-type PbTe over a long period of time, primarily due to the generation of intrinsic Pb vacancies and other defects. In this work, PbTe samples with nonstoichiometric excess Pb atoms were successfully prepared by a melting reaction followed by spark plasma sintering. First, the introduction of precisely controlled excess Pb atoms has effectively eliminated the typical p-n transition phenomenon in PbTe systems by suppressing the generation of Pb vacancies. Further, the vacuum annealing process employed in nonstoichiometric samples increases the carrier mobility significantly because of the improved crystallinity and the lowered holes. Thus, the Hall mobility was optimized from 754.3 to 1215.9 cm2 V-1 s-1, while the power factor was ultimately elevated from 3087.8 to 4565.7 µW m-1 K-2 for the Pb1.03Te sample at 323 K. Benefited from the enhanced electrical transport properties near room temperature, an average zT ∼ 1.03 ranging from 323 to 723 K was achieved, demonstrating an outstanding performance in n-type nondoped PbTe. This work provides guidance for optimizing the thermoelectric performance of n-type PbTe and relevant telluride by reducing vacancies and other defects.

20.
Talanta ; 274: 125934, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38574533

RESUMO

Nowadays, novel and efficient signal amplification strategy in electrochemiluminescence (ECL) platform is urgently needed to enhance the sensitivity of biosensor. In this work, the dual ECL signal enhancement strategy was constructed by the interactions of Pd nanoparticles attached covalent organic frameworks (Pd NPs@COFs) with tris (bipyridine) ruthenium (RuP) and Exonuclease III (Exo.III) cycle reaction. Within this strategy, the COFs composite was generated from the covalent reaction between 2-nitro-1,4-phenylenediamine (NPD) and trialdehyde phloroglucinol (Tp), and then animated by glutamate (Glu) to attach the Pd NPs. Next, the "signal on" ECL biosensor was constructed by the coordination assembly of thiolation capture DNA (cDNA) onto the Pd NPs@COFs modified electrode. After the aptamer recognition of progesterone (P4) with hairpin DNA 1 (HP1), the Exo. III cycle reaction was initiated with HP2 to generate free DNA, which hybridized with cDNA to form double-stranded DNA (dsDNA). For that, the RuP was embedded into the groove of dsDNA and achieved the ultrasensitive detection of P4 with a lower limit of detection (LOD) down to 0.45 pM, as well as the excellent selectivity and stability. This work expands the COFs-based materials application in ECL signal amplification and valuable DNA cyclic reaction in biochemical testing field.

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