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1.
Nature ; 569(7754): 99-103, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043727

RESUMO

Since their discovery in 19601, metallic glasses based on a wide range of elements have been developed2. However, the theoretical prediction of glass-forming compositions is challenging and the discovery of alloys with specific properties has so far largely been the result of trial and error3-8. Bulk metallic glasses can exhibit strength and elasticity surpassing those of conventional structural alloys9-11, but the mechanical properties of these glasses are critically dependent on the glass transition temperature. At temperatures approaching the glass transition, bulk metallic glasses undergo plastic flow, resulting in a substantial decrease in quasi-static strength. Bulk metallic glasses with glass transition temperatures greater than 1,000 kelvin have been developed, but the supercooled liquid region (between the glass transition and the crystallization temperature) is narrow, resulting in very little thermoplastic formability, which limits their practical applicability. Here we report the design of iridium/nickel/tantalum metallic glasses (and others also containing boron) with a glass transition temperature of up to 1,162 kelvin and a supercooled liquid region of 136 kelvin that is wider than that of most existing metallic glasses12. Our Ir-Ni-Ta-(B) glasses exhibit high strength at high temperatures compared to existing alloys: 3.7 gigapascals at 1,000 kelvin9,13. Their glass-forming ability is characterized by a critical casting thickness of three millimetres, suggesting that small-scale components for applications at high temperatures or in harsh environments can readily be obtained by thermoplastic forming14. To identify alloys of interest, we used a simplified combinatorial approach6-8 harnessing a previously reported correlation between glass-forming ability and electrical resistivity15-17. This method is non-destructive, allowing subsequent testing of a range of physical properties on the same library of samples. The practicality of our design and discovery approach, exemplified by the identification of high-strength, high-temperature bulk metallic glasses, bodes well for enabling the discovery of other glassy alloys with exciting properties.

2.
Drug Resist Updat ; 74: 101077, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38518726

RESUMO

PURPOSE: Ovarian cancer patients with HR proficiency (HRP) have had limited benefits from PARP inhibitor treatment, highlighting the need for improved therapeutic strategies. In this study, we developed a novel SIK2 inhibitor, SIC-19, and investigated its potential to enhance the sensitivity and expand the clinical utility of PARP inhibitors in ovarian cancer. METHODS: The SIK2 protein was modeled using a Molecular Operating Environment (MOE), and the most favorable model was selected based on a GBVI/WSA dG scoring function. The Chembridge Compound Library was screened, and the top 20 candidate compounds were tested for their interaction with SIK2 and downstream substrates, AKT-pS473 and MYLK-pS343. SIC-19 emerged as the most promising drug candidate and was further evaluated using multiple assays. RESULTS: SIC-19 exhibited selective and potent inhibition of SIK2, leading to its degradation through the ubiquitination pathway. The IC50 of SIC-19 correlated inversely with endogenous SIK2 expression in ovarian cancer cell lines. Treatment with SIC-19 significantly inhibited cancer cell growth and sensitized cells to PARP inhibitors in vitro, as well as in ovarian cancer organoids and xenograft models. Mechanistically, SIK2 knockdown and SIC-19 treatment reduced RAD50 phosphorylation at Ser635, prevented nuclear translocation of RAD50, disrupted nuclear filament assembly, and impaired DNA homologous recombination repair, ultimately inducing apoptosis. These findings highlight the crucial role of SIK2 in the DNA HR repair pathway and demonstrate the significant PARP inhibitor sensitization achieved by SIC-19 in ovarian cancer. CONCLUSIONS: SIC-19, a novel SIK2 inhibitor, effectively inhibits tumor cell growth in ovarian cancer by interfering with RAD50-mediated DNA HR repair. Furthermore, SIC-19 enhances the efficacy of PARP inhibitors, providing a promising therapeutic strategy to improve outcomes for ovarian cancer patients.


Assuntos
Neoplasias Ovarianas , Inibidores de Poli(ADP-Ribose) Polimerases , Proteínas Serina-Treonina Quinases , Mutações Sintéticas Letais , Animais , Feminino , Humanos , Camundongos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Camundongos Nus , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Mutações Sintéticas Letais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
3.
PLoS Med ; 21(5): e1004389, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38728364

RESUMO

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Camptotecina , Cetuximab , Neoplasias Colorretais , Fluoruracila , Leucovorina , Neoplasias Hepáticas , Compostos Organoplatínicos , Proteínas Proto-Oncogênicas B-raf , Humanos , Cetuximab/administração & dosagem , Cetuximab/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/tratamento farmacológico , Feminino , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Leucovorina/uso terapêutico , Leucovorina/administração & dosagem , Fluoruracila/uso terapêutico , Fluoruracila/administração & dosagem , Compostos Organoplatínicos/uso terapêutico , Compostos Organoplatínicos/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/genética , Idoso , Adulto , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Camptotecina/administração & dosagem , Resultado do Tratamento , Proteínas ras/genética
4.
Br J Cancer ; 130(5): 861-868, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38195887

RESUMO

BACKGROUND: Multiple antigens, autoantibodies (AAb), and antigen-autoantibody (Ag-AAb) complexes were compared for their ability to complement CA125 for early detection of ovarian cancer. METHODS: Twenty six biomarkers were measured in a single panel of sera from women with early stage (I-II) ovarian cancers (n = 64), late stage (III-IV) ovarian cancers (186), benign pelvic masses (200) and from healthy controls (502), and then split randomly (50:50) into a training set to identify the most promising classifier and a validation set to compare its performance to CA125 alone. RESULTS: Eight biomarkers detected ≥ 8% of early stage cases at 98% specificity. A four-biomarker panel including CA125, HE4, HE4 Ag-AAb and osteopontin detected 75% of early stage cancers in the validation set from among healthy controls compared to 62% with CA125 alone (p = 0.003) at 98% specificity. The same panel increased sensitivity for distinguishing early-stage ovarian cancers from benign pelvic masses by 25% (p = 0.0004) at 95% specificity. From 21 autoantibody candidates, 3 AAb (anti-p53, anti-CTAG1 and annt-Il-8) detected 22% of early stage ovarian cancers, potentially lengthening lead time prior to diagnosis. CONCLUSION: A four biomarker panel achieved greater sensitivity at the same specificity for early detection of ovarian cancer than CA125 alone.


Assuntos
Autoanticorpos , Neoplasias Ovarianas , Feminino , Humanos , Sensibilidade e Especificidade , Curva ROC , Antígeno Ca-125 , Biomarcadores Tumorais , Neoplasias Ovarianas/diagnóstico
5.
BMC Med ; 22(1): 207, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769543

RESUMO

BACKGROUND: Tumor-infiltrating lymphocyte (TIL) therapy has been restricted by intensive lymphodepletion and high-dose intravenous interleukin-2 (IL-2) administration. To address these limitations, we conducted preclinical and clinical studies to evaluate the safety, antitumor activity, and pharmacokinetics of an innovative modified regimen in patients with advanced gynecologic cancer. METHODS: Patient-derived xenografts (PDX) were established from a local recurrent cervical cancer patient. TILs were expanded ex vivo from minced tumors without feeder cells in the modified TIL therapy regimen. Patients underwent low-dose cyclophosphamide lymphodepletion followed by TIL infusion without intravenous IL-2. The primary endpoint was safety; the secondary endpoints included objective response rate, duration of response, and T cell persistence. RESULTS: In matched patient-derived xenografts (PDX) models, homologous TILs efficiently reduced tumor size (p < 0.0001) and underwent IL-2 absence in vivo. In the clinical section, all enrolled patients received TIL infusion using a modified TIL therapy regimen successfully with a manageable safety profile. Five (36%, 95% CI 16.3-61.2) out of 14 evaluable patients experienced objective responses, and three complete responses were ongoing at 19.5, 15.4, and 5.2 months, respectively. Responders had longer overall survival (OS) than non-responders (p = 0.036). Infused TILs showed continuous proliferation and long-term persistence in all patients and showed greater proliferation in responders which was indicated by the Morisita overlap index (MOI) of TCR clonotypes between infused TILs and peripheral T cells on day 14 (p = 0.004) and day 30 (p = 0.004). Higher alteration of the CD8+/CD4+ ratio on day 14 indicated a longer OS (p = 0.010). CONCLUSIONS: Our modified TIL therapy regimen demonstrated manageable safety, and TILs could survive and proliferate without IL-2 intravenous administration, showing potent efficacy in patients with advanced gynecologic cancer. TRIAL REGISTRATION: NCT04766320, Jan 04, 2021.


Assuntos
Interleucina-2 , Linfócitos do Interstício Tumoral , Humanos , Feminino , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Pessoa de Meia-Idade , Interleucina-2/administração & dosagem , Interleucina-2/uso terapêutico , Animais , Idoso , Adulto , Camundongos , Neoplasias dos Genitais Femininos/terapia , Neoplasias dos Genitais Femininos/tratamento farmacológico , Resultado do Tratamento , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Inibidores de Checkpoint Imunológico/administração & dosagem , Inibidores de Checkpoint Imunológico/uso terapêutico
6.
Blood Cells Mol Dis ; 107: 102858, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38796983

RESUMO

Immune thrombocytopenia (ITP) is an autoimmune disease caused by the loss of immune tolerance to platelet autoantigens, resulting in reduced platelet production and increased platelet destruction. Impaired megakaryocyte differentiation and maturation is a key factor in the pathogenesis and treatment of ITP. Sarcandra glabra, a plant of the Chloranthaceae family, is commonly used in clinical practice to treat ITP, and daucosterol (Dau) is one of its active ingredients. However, whether Dau can treat ITP and the key mechanism of its effect are still unclear. In this study, we found that Dau could effectively promote the differentiation and maturation of megakaryocytes and the formation of polyploidy in the megakaryocyte differentiation disorder model constructed by co-culturing Dami and HS-5 cells. In vivo experiments showed that Dau could not only increase the number of polyploidized megakaryocytes in the ITP rat model, but also promote the recovery of platelet count. In addition, through network pharmacology analysis, we speculated that the JAK2-STAT3 signaling pathway might be involved in the process of Dau promoting megakaryocyte differentiation. Western blot results showed that Dau inhibited the expression of P-JAK2 and P-STAT3. In summary, these results provide a basis for further studying the pharmacological mechanism of Dau in treating ITP.


Assuntos
Diferenciação Celular , Janus Quinase 2 , Megacariócitos , Púrpura Trombocitopênica Idiopática , Fator de Transcrição STAT3 , Transdução de Sinais , Animais , Humanos , Masculino , Ratos , Diferenciação Celular/efeitos dos fármacos , Modelos Animais de Doenças , Janus Quinase 2/metabolismo , Megacariócitos/metabolismo , Megacariócitos/efeitos dos fármacos , Megacariócitos/citologia , Púrpura Trombocitopênica Idiopática/metabolismo , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/patologia , Transdução de Sinais/efeitos dos fármacos , Sitosteroides/farmacologia , Fator de Transcrição STAT3/metabolismo
7.
J Med Virol ; 96(1): e29350, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38180233

RESUMO

Chronic viral infection induces immunosenescence and systemic low-grade inflammation, leading to worsened long-term outcomes. We sought to explore the short- and long-term effects of chronic viral infection on cardiovascular disease (CVD). Based on UK Biobank data, exposed group was identified as individuals who had chronic virus infection-related hospitalization (IRH). Unexposed group was randomly selected, matched by 5-year age interval, sex, and Charlson comorbidity index at a ratio up to 1:10. Restricted cubic splines were used to model time-varying effects of IRH in nonproportional Cox models. A cut-off value of 5 years was recorded and used in piecewise Cox proportional hazards models as we estimated short- and long-term effects of IRH on CVD. A total of 2826 exposed participants and 28 212 matched unexposed participants were included. Chronic viral IRH was associated with increased risk of CVD (0-5 years: hazard ratio, 1.57 [95% confidence interval: 1.32, 1.87] and 5+ years: 1.31 [1.06, 1.61]). Elevated risk of stroke was only observed within the initial 5-year follow-up (0-5 years: 1.91 [1.30, 2.81]). The short- and long-term associations were observed in herpes or hepatitis virus IRH with risk of CVD (all p < 0.05). Subgroup analysis revealed long-term association between chronic viral IRH and CVD among female (5+ years: 1.68 [1.27, 2.22]) but not among male. The association between chronic viral infection and elevated CVD risk appeared to be stronger among individuals who did not take cholesterol-lowering medication, antithrombotic medication, or certain antihypertensive medications (all p for interaction < 0.05). The risk of CVD event remained persistently higher within and over 5 years following chronic viral IRH, especially in individuals infected with herpes and hepatitis virus.


Assuntos
Doenças Cardiovasculares , Imunossenescência , Humanos , Feminino , Masculino , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Anti-Hipertensivos , Hospitalização , Infecção Persistente
8.
Opt Express ; 32(7): 12645-12655, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571082

RESUMO

The space time frequency transfer plays a crucial role in applications such as space optical clock networks, navigation, satellite ranging, and space quantum communication. Here, we propose a high-precision space time frequency transfer and time synchronization scheme based on a simple intensity modulation/direct detection (IM/DD) laser communication system, which occupies a communication bandwidth of approximately 0.2%. Furthermore, utilizing an optical-frequency comb time frequency transfer system as an out-of-loop reference, experimental verification was conducted on a 113 km horizontal atmospheric link, with a long-term stability approximately 8.3 × 10-16 over a duration of 7800 seconds. Over an 11-hour period, the peak-to-peak wander is approximately 100 ps. Our work establishes the foundation of the time frequency transfer, based on the space laser communication channel, for future ground-to-space and inter-satellite links.

9.
Toxicol Appl Pharmacol ; 483: 116816, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38218207

RESUMO

Phthalates (PEs), such as di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and butyl benzyl phthalate (BBP) could cause reproductive and developmental toxicities, while human beings are increasingly exposed to them at low-doses. Phytochemical quercetin (Que) is a flavonoid that has estrogenic effect, anti-inflammatory and anti-oxidant effects. This study was conducted to assess the alleviative effect of Que. on male reproductive toxicity induced by the mixture of three commonly used PEs (MPEs) at low-dose in rats, and explore the underlying mechanism. Male rats were treated with MPEs (16 mg/kg/day) and/or Que. (50 mg/kg/d) for 91 days. The results showed that MPEs exposure caused male reproductive injuries, such as decreased serum sex hormones levels, abnormal testicular pathological structure, increased abnormal sperm rate and changed expressions of PIWIL1 and PIWIL2. Furthermore, MPEs also changed the expression of steroidogenic proteins in steroid hormone metabolism, including StAR, CYP11A1, CYP17A1, 17ß-HSD, CYP19A1. However, the alterations of these parameters were reversed by Que. MPEs caused male reproductive injuries in rats; Que. inhibited MPEs' male reproductive toxicity, which might relate to the improvement of testosterone biosynthesis.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Humanos , Ratos , Masculino , Animais , Quercetina/farmacologia , Testosterona , Ratos Sprague-Dawley , Sêmen/metabolismo , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/metabolismo , Testículo , Dietilexilftalato/toxicidade , Proteínas Argonautas/metabolismo , Proteínas Argonautas/farmacologia
10.
BMC Cardiovasc Disord ; 24(1): 278, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811882

RESUMO

BACKGROUND: Left ventricular thrombus (LVT) is a serious complication after myocardial infarction. However, due to its asymptomatic nature, early detection is challenging. We aimed to explore the differences in clinical correlates of LVT found in acute to subacute and chronic phases of myocardial infarction. METHODS: We collected data from 153 patients who were diagnosed with LVT after myocardial infarction at the Affiliated Hospital of Qingdao University from January 2013 to December 2022. Baseline information, inflammatory markers, transthoracic echocardiograph (TTE) data and other clinical correlates were collected. Patients were categorized into acute to subacute phase group (< 30 days) and chronic phase group (30 days and after) according to the time at which echocardiograph was performed. The resolution of thrombus within 90 days is regarded as the primary endpoint event. We fitted logistic regression models to relating clinical correlates with phase-specific thrombus resolution. RESULTS: For acute to subacute phase thrombus patients: C-reactive protein levels (OR: 0.95, 95% CI: 0.918-0.983, p = 0.003) were significantly associated with thrombus resolution. For chronic phase thrombus patients: anticoagulant treatment was associated with 5.717-fold odds of thrombus resolution (OR: 5.717, 95% CI: 1.543-21.18, p = 0.009). CONCLUSIONS: Higher levels of CRP were associated with lower likelihood of LVT resolution in acute phase myocardial infarction; Anticoagulant therapy is still needed for thrombus in the chronic stage of myocardial infarction.


Assuntos
Trombose , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Fatores de Tempo , Trombose/diagnóstico por imagem , Trombose/etiologia , Idoso , Fatores de Risco , Anticoagulantes/uso terapêutico , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Estudos Retrospectivos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico , Biomarcadores/sangue , Resultado do Tratamento , Cardiopatias/diagnóstico por imagem , Cardiopatias/etiologia , Cardiopatias/diagnóstico , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , China , Ecocardiografia , Função Ventricular Esquerda
11.
J Chem Ecol ; 50(3-4): 185-196, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38441803

RESUMO

Sea cucumbers frequently expel their guts in response to predators and an aversive environment, a behavior perceived as releasing repellents involved in chemical defense mechanisms. To investigate the chemical nature of the repellent, the viscera of stressed sea cucumbers (Apostichopus japonicus) in the Yellow Sea of China were collected and chemically analyzed. Two novel non-holostane triterpene glycosides were isolated, and the chemical structures were elucidated as 3ꞵ-O-[ꞵ-D-glucopyranosyl-(1→2)-ꞵ-D-xylopyranosyl]-(20S)-hydroxylanosta-7,25-diene-18(16)-lactone (1) and 3ꞵ-O-[ꞵ-D-quinovopyranosyl-(1→2)-ꞵ-D-xylopyranosyl]-(20S)-hydroxylanosta-7,25-diene-18(16)-lactone (2) by spectroscopic and mass-spectrometric analyses, exemplifying a triterpene glycoside constituent of an oligosaccharide containing two sugar-units and a non-holostane aglycone. Zebrafish embryos were exposed to various doses of 1 and 2 from 4 to 96 hpf. Compound 1 exposure showed 96 h-LC50 41.5 µM and an increased zebrafish mortality rates in roughly in a dose- and time-dependent manner. Compound 2, with different sugar substitution, exhibited no mortality and moderate teratogenic toxicity with a 96 h-EC50 of 173.5 µM. Zebrafish embryos exhibited teratogenic effects, such as reduced hatchability and total body length. The study found that triterpene saponin from A. japonicus viscera had acute toxicity in zebrafish embryos, indicating a potential chemical defense role in the marine ecosystem.


Assuntos
Glicosídeos , Pepinos-do-Mar , Triterpenos , Vísceras , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Glicosídeos/química , Glicosídeos/toxicidade , Glicosídeos/metabolismo , Vísceras/química , Vísceras/efeitos dos fármacos , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/metabolismo , Pepinos-do-Mar/química , Embrião não Mamífero/efeitos dos fármacos , Toxinas Marinhas/toxicidade , Toxinas Marinhas/química
12.
J Chem Phys ; 160(4)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38258930

RESUMO

Glass transition, commonly manifested upon cooling a liquid, is continuous and cooling rate dependent. For decades, the thermodynamic basis in liquid-glass transition has been at the center of debate. Here, long-time isothermal annealing was conducted via molecular dynamics simulations for metallic glasses to explore the connection of physical aging in supercooled liquid and glassy states. An anomalous two-step aging is observed in various metallic glasses, exhibiting features of supercooled liquid dynamics in the first step and glassy dynamics in the second step, respectively. Furthermore, the transition potential energy is independent of initial states, proving that it is intrinsic for a metallic glass at a given temperature. We propose that the observed dynamic transition from supercooled liquid dynamics to glassy dynamics could be glass transition manifested isothermally. On this basis, glass transition is no longer cooling rate dependent, but is shown as a clear phase boundary in the temperature-energy phase diagram. Hence, a modified out-of-equilibrium phase diagram is proposed, providing new insights into the nature of glass transition.

13.
Ecotoxicol Environ Saf ; 270: 115920, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38171105

RESUMO

Phthalates (PEs) are widely used plasticizers in polymer products, and humans are increasingly exposed to them. This study was designed to investigate the alleviative effect of phytochemicals quercetin (Que) against male reproductive toxicity caused by the mixture of three commonly used PEs (MPEs), and further to explore the underlying mechanism. Forty-eight male SD rats were randomly and evenly divided into control group, Que group, MPEs group and MPEs+Que group (n = 12); The oral exposure doses of MPEs and Que were 450 mg/kg/d and 50 mg/kg/d, respectively. After 91 days of continuous intervention, compared with control group, the testes weight, epididymis weight, serum sex hormones, and anogenital distance were significantly decreased in MPEs group (P < 0.05); Testicular histopathological observation showed that all seminiferous tubules were atrophy, leydig cells were hyperplasia, spermatogenic cells growth were arrested in MPEs group. Ultrastructural observation of testicular germ cells showed that the edges of the nuclear membranes were indistinct, and the mitochondria were severely damaged with the cristae disrupted, decreased or even disappeared in MPEs group. Immunohistochemistry and Western blot analysis showed that testicular CYP11A1, CYP17A1 and 17ß-HSD were up-regulated, while StAR, PIWIL1 and PIWIL2 were down-regulated in MPEs group (P < 0.05); However, the alterations of these parameters were restored in MPEs+Que group. The results indicated MPEs disturbed steroid hormone metabolism, and caused male reproductive injuries; whereas, Que could inhibit MPEs' male reproductive toxicity, which might relate to the restored regulation of steroid hormone metabolism.


Assuntos
Ácidos Ftálicos , Quercetina , Testículo , Humanos , Ratos , Masculino , Animais , Quercetina/farmacologia , Ratos Sprague-Dawley , Hormônios Esteroides Gonadais/metabolismo , Esteroides/metabolismo , Testosterona , Proteínas Argonautas/metabolismo , Proteínas Argonautas/farmacologia
14.
Ecotoxicol Environ Saf ; 281: 116684, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38968728

RESUMO

Fish egg poisoning is a serious and neglected public menace that kills hundreds of people and numerous poultry each year. Freshwater groupers (Acrossocheilus fasciatus) are common food fish in the southeastern regions of China. Their toxic eggs are regarded as a significant public health concern. The molecular mechanisms of egg-toxin toxicity in freshwater grouper to poisoned organisms are elusive. In this study, black-boned chicks were exposed to toxic eggs from freshwater grouper at a lethal dose. The hepatic morphology of the intoxicated chick was assessed. An analysis of the liver gene expression profile was conducted by comparing samples exposed to toxic eggs with control samples using RNA-Seq. The result revealed that an increase in vacuolation and congestion was observed in chicks with toxic eggs exposure. The transcriptome analysis revealed 5421 genes with differential expression, comprising 2810 up-regulated and 2611 down-regulated genes. The genes were primarily linked to energy metabolism, cell apoptosis, cell adhesion, exogenous microbial infection, and cell junction. The most strongly upregulated genes were cholecystokinin (CCK), cholecystokinin A receptor (CCKAR), and unc-80 homolog, NALCN activator (UNC80), and the most downregulated genes were glycine amidinotransferase (GATM), fatty acid desaturase 2 (FADS2), and hexokinase 2 (HKDC1). GO term with the highest enrichment of DEGs is nucleosome assembly. According to KEGG pathways, the three most significant metabolic pathways in the liver are DNA replication, retinol metabolism, and steroid biosynthesis. The results could be crucial for comprehending the negative biological impacts of egg-toxin and its toxic mechanisms. The outcome could provide potential biomarkers of egg-toxin exposure in hepatic, which might be useful for manufacturing an antidote to egg-toxin and providing valuable insights for ecotoxicity studies.


Assuntos
Fígado , Transcriptoma , Animais , Fígado/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Galinhas/genética , Bass/genética , China , Água Doce
15.
Ecotoxicol Environ Saf ; 280: 116540, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38833982

RESUMO

The widespread utilization of polyethylene terephthalate (PET) has caused a variety of environmental and health problems. Compared with traditional thermomechanical or chemical PET cycling, the biodegradation of PET may offer a more feasible solution. Though the PETase from Ideonalla sakaiensis (IsPETase) displays interesting PET degrading performance under mild conditions; the relatively low thermal stability of IsPETase limits its practical application. In this study, enzyme-catalysed PET degradation was investigated with the promising IsPETase mutant HotPETase (HP). On this basis, a carbohydrate-binding module from Bacillus anthracis (BaCBM) was fused to the C-terminus of HP to construct the PETase mutant (HLCB) for increased PET degradation. Furthermore, to effectively improve PET accessibility and PET-degrading activity, the truncated outer membrane hybrid protein (FadL) was used to expose PETase and BaCBM on the surface of E. coli (BL21with) to develop regenerable whole-cell biocatalysts (D-HLCB). Results showed that, among the tested small-molecular weight ester compounds (p-nitrophenyl phosphate (pNPP), p-Nitrophenyl acetate (pNPA), 4-Nitrophenyl butyrate (pNPB)), PETase displayed the highest hydrolysing activity against pNPP. HP displayed the highest catalytic activity (1.94 µM(p-NP)/min) at 50 °C and increased longevity at 40 °C. The fused BaCBM could clearly improve the catalytic performance of PETase by increasing the optimal reaction temperature and improving the thermostability. When HLCB was used for PET degradation, the yield of monomeric products (255.7 µM) was ∼25.5 % greater than that obtained after 50 h of HP-catalysed PET degradation. Moreover, the highest yield of monomeric products from the D-HLCB-mediated system reached 1.03 mM. The whole-cell catalyst D-HLCB displayed good reusability and stability and could maintain more than 54.6 % of its initial activity for nine cycles. Finally, molecular docking simulations were utilized to investigate the binding mechanism and the reaction mechanism of HLCB, which may provide theoretical evidence to further increase the PET-degrading activities of PETases through rational design. The proposed strategy and developed variants show potential for achieving complete biodegradation of PET under mild conditions.


Assuntos
Biodegradação Ambiental , Burkholderiales , Escherichia coli , Polietilenotereftalatos , Polietilenotereftalatos/química , Polietilenotereftalatos/metabolismo , Burkholderiales/enzimologia , Escherichia coli/genética , Bacillus anthracis/enzimologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Engenharia de Proteínas
16.
Chem Biodivers ; 21(6): e202400335, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38456571

RESUMO

Sea cucumbers release chemical repellents from their guts when they are in danger from predators or a hostile environment. To investigate the chemical structure of the repellent, we collected and chemically analyzed the viscera of stressed sea cucumbers (Apostichopus japonicus) in the Yellow Sea of China. Two undescribed triterpene glycosides (1 and 2), together with a known cladoloside A (3), were identified and elucidated as 3ß-O-{2-O-[ß-d-quinovopyranosyl]-4-O-[3-O-methyl-ß-d-glucopyranosyl-(1→3)-ß-d-glucopyranosyl]-ß-d-xylopyranosyl}-holosta-9(11),25(26)-dien-16-one (1), 3ß-O-{2-O-[ß-d-glucopyranosyl]-4-O-[3-O-methyl-ß-d-glucopyranosyl-(1→3)-ß-d-glucopyranosyl]-ß-d-xylopyranosyl}-holosta-9(11),25(26)-dien-16-one (2), 3ß-O-{2-O-[3-O-methyl-ß-d-glucopyranosyl-(1→3)-ß-d-xylopyranosyl-(1→4)-ß-d-quinovopyranosyl]-ß-d-xylopyranosyl}-holosta-9(11),25(26)-dien-16-one (3) by spectroscopic analysis, including HR-ESI-MS and NMR spectra. Compounds 1, 2, and 3 display embryonic toxicity, as indicated by their 96-hour post-fertilization lethal concentration (96 hpf-LC50) values of 0.289, 0.536, and 0.091 µM, respectively. Our study discovered a class of triterpene glycoside compounds consisting of an oligosaccharide with four sugar units and a holostane aglycone. These compounds possess embryotoxicity and may serve as chemical defense molecules in marine benthic ecosystems.


Assuntos
Glicosídeos , Triterpenos , Animais , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/toxicidade , Triterpenos/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Stichopus/química , Vísceras/química , Pepinos-do-Mar/química , Embrião não Mamífero/efeitos dos fármacos
17.
Environ Toxicol ; 39(6): 3330-3340, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38440903

RESUMO

OBJECTIVE: Phthalates (PEs) could cause reproductive harm to males. A mixture of three widely used PEs (MPEs) was used to investigate the ameliorative effects of zinc (Zn) and vitamin E (VE) against male reproductive toxicity. METHODS: Fifty male SD rats were randomly divided into five groups (n = 10). Rats in MPEs group were orally treated with 160 mg/kg/d MPEs, while rats in MPEs combined Zn and/or VE groups were treated with 160 mg/kg/d MPEs plus 25 mg/kg/d Zn and/or 25 mg/kg/d VE. After intervention for 70 days, it's was measured of male reproductive organs' weight, histopathological observation of sperms and testes, serum hormones, PIWI proteins and steroidogenic proteins. RESULTS: Compared with control, anogenital distance, testes weight, epididymides weight, and sex hormones were significantly decreased, while the sperm malformation rate was markedly increased in MPEs group (p < .05); the testicular tissues were injured in MPEs group with disordered and decreased spermatids, and arrested spermatogenesis. PIWIL1, PIWIL2, StAR, CYP11A1 and CYP19A1 were down-regulated in MPEs group (p < .05). However, the alterations of these parameters were restored in MPEs combined Zn and/or VE groups (p < .05). CONCLUSION: Zn and/or VE improved steroid hormone metabolism, and inhibited MPEs' male reproductive toxicity.


Assuntos
Ácidos Ftálicos , Ratos Sprague-Dawley , Testículo , Vitamina E , Zinco , Animais , Masculino , Testículo/efeitos dos fármacos , Testículo/patologia , Vitamina E/farmacologia , Ácidos Ftálicos/toxicidade , Espermatozoides/efeitos dos fármacos , Ratos , Reprodução/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos
18.
Molecules ; 29(13)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38999175

RESUMO

Transition metal selenides have the leading position in the field of energy storage and conversion due to their high theoretical capacity, good electrical conductivity, and cycling stability. Nickel is widely used for the construction of positive electrodes in devices due to its good conductivity, variable valence state, and ideal redox activity. NiSe materials have high internal resistance and are prone to volume change during charging and discharging, thus affecting the practical application of this electrode material, and the reported NiSe materials have not achieved a more desirable capacity value. Therefore, in this study, N, P-NiSe nanoelectrode materials were prepared using nickel foam as the nickel source and hexachlorocyclotriphonitrile as the nitrogen and phosphorus dopant using an efficient, energy-saving, and simple microwave method. It was also characterised by XRD and XPS to confirm the successful preparation of N, P-NiSe materials. In addition, the material yielded a high capacitance value (3184 F g-1) and good cycling stability (72% of the initial capacitance value was retained after 4000 cycles) in electrochemical tests. To demonstrate its excellent suitability for practical applications, an asymmetric supercapacitor was assembled using N, P-NiSe as the anode and activated carbon as the cathode. At an operating voltage of 1.6 V, the device achieved an energy density of 289.06 Wh kg-1 and a power density of 799.26 W kg-1 and retained 80% of its initial capacity after 20,000 cycles.

19.
Nurs Crit Care ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955501

RESUMO

BACKGROUND: Critical patients may experience various adverse events during transportation within hospitals. Therefore, quickly evaluating and classifying patients before transporting them from the emergency department and focusing on managing high-risk patients are critical. At present, no unified classification method exists; all the current approaches are subjective. AIMS: To ensure transportation safety, we conducted a cluster analysis of critically ill patients transferred from the emergency department to the intensive care unit. STUDY DESIGN: Single-centre cohort study. This study was conducted at a comprehensive first-class teaching hospital in Beijing. Convenience sampling and continuous enrolment were employed. We collected data from 1 January 2019, to 31 December 2021. All patients were transferred from the emergency department to the intensive care unit, and cluster analysis was conducted using five variables. RESULTS: A total of 584 patients were grouped into three clusters. Cluster 1 (high systolic blood pressure group) included 208 (35.6%) patients. Cluster 2 (high heart rate and low blood oxygen group) included 55 (9.4%) patients. Cluster 3 (normal group) included the remaining 321 (55%) patients. The oxygen saturation levels of all the patients were lower after transport, and the proportion of adverse events (61.8%) was the highest in Cluster 2 (p < .05). CONCLUSIONS: This study utilized data on five important vital signs from a cluster analysis to explore possible patient classifications and provide a reference for ensuring transportation safety. RELEVANCE TO CLINICAL PRACTICE: Before transferring patients, we should classify them and implement targeted care. Changes in blood oxygen levels in all patients should be considered, with a focus on the occurrence of adverse events during transportation among patients with high heart rates and low blood oxygen levels.

20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(3): 458-461, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-38953271

RESUMO

Intestinal mantle cell lymphoma complicated with intussusception is rare in clinical practice,lacking specific clinical manifestations.CT and colonoscopy are helpful for the diagnosis of this disease,which need to be distinguished from colorectal cancer,Crohn's disease,and other pathological subtypes of lymphoma.The diagnosis still needs to be confirmed by pathological examination.This paper reports a case of intestinal mantle cell lymphoma complicated with ileocecal intussusception in an adult,aiming to improve the clinical and imaging doctors' understanding of this disease.


Assuntos
Doenças do Íleo , Intussuscepção , Linfoma de Célula do Manto , Humanos , Linfoma de Célula do Manto/complicações , Intussuscepção/etiologia , Intussuscepção/diagnóstico por imagem , Intussuscepção/complicações , Masculino , Doenças do Íleo/etiologia , Doenças do Íleo/complicações , Doenças do Íleo/diagnóstico por imagem , Neoplasias Intestinais/complicações , Neoplasias Intestinais/patologia , Neoplasias Intestinais/diagnóstico por imagem , Pessoa de Meia-Idade , Valva Ileocecal/diagnóstico por imagem , Valva Ileocecal/patologia
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