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1.
Nat Mater ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951651

RESUMO

Solution-processed colloidal nanocrystals of lead halide perovskites have been intensively investigated in recent years in the context of optoelectronic devices, during which time their quantum properties have also begun to attract attention. Their unmatched ease of synthetic tunability and unique structural, optical and electronic properties, in conjunction with the confinement of carriers in three dimensions, have motivated studies on observing and controlling coherent light-matter interaction in these materials for quantum information technologies. This Review outlines the recent efforts and achievements in this direction. Particularly notable examples are the observation of coherent single-photon emission, evidence for superfluorescence and the realization of room-temperature coherent spin manipulation for ensemble samples, which have not been achieved for prototypical colloidal CdSe nanocrystals that have been under investigation for decades. This Review aims to highlight these results, point out the challenges ahead towards realistic applications and bring together the efforts of multidisciplinary communities in this nascent field.

2.
Small ; 20(15): e2307620, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009487

RESUMO

Triboelectric nanogenerators (TENGs) have emerged as a promising technology for harvesting mechanical energy from the ambient environment. However, developing tribopositive materials with strong piezoelectric effects and high electron-donating ability still remains a challenge. Herein, poly(ethylene glycol) monomethyl ether (mPEG) to soft poly(lactic acid) (PLA) is adopted, then PLA/mPEG nanofibers are fabricated under electrospinning and used as the tribopositive material for fabricating robust power density TENGs. The crystallinity and dynamic mechanical properties of PLA/mPEG nanofibers are investigated. The results revealed that the incorporation of mPEG provided an effective approach to elevate the electron-donating ability and charge transfer efficiency in PLA. The PLA/mPEG-based TENGs achieved a high open-circuit voltage of 342.8 V, a short-circuit current of 38.5 µA, and a maximum power density of 116.21 W m-2 over a 2 cm2 contact area at an external load of 106 Ω, respectively. Strikingly, excellent stability and durability are demonstrated after continuous cycles up to 104 cycles. Noteworthy, the TENGs are explored for self-powered sensing applications, with seven TENG units integrated to act as self-powered sensors playing music through buzzers when pressed by fingers. Eventually, this work provides new insights into tuning the structures and properties of electrospun polymers to reinforce the TENG output and self-powered systems.

3.
Am J Pathol ; 193(6): 769-777, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36868466

RESUMO

Neurofibromas (NFs), Bowen disease (BD), and seborrheic keratosis (SK) are common skin tumors. Pathologic examination is the gold standard for diagnosis of these tumors. Current pathologic diagnosis is primarily based on microscopic observation, which is laborious and time-consuming. With digitization, artificial intelligence can be used to improve the efficiency of pathologic diagnosis. This research aims to develop an end-to-end extendable framework for the diagnosis of skin tumor based on pathologic slide images. NF, BD, and SK were selected as target skin tumors. A two-stage skin cancer diagnosis framework is proposed in this article, which consists of two parts: patches-wise diagnosis, and slide-wise diagnosis. Patches-wise diagnosis compares different convolutional neural networks to extract features and distinguish categories from patches generated in whole slide images. Slide-wise diagnosis combines attention graph gated network model prediction with post-processing algorithm. This approach can fuse information from feature-embedding learning and domain knowledge to draw conclusions. Training, validation, and testing were performed on NF, BD, SK, and negative samples. Accuracy and receiver operating characteristic curves were used to evaluate the classification performance. This study investigated the feasibility of skin tumor diagnosis from pathologic images and may be the first instance of applying deep learning to address these three types of tumor diagnoses in skin pathology.


Assuntos
Aprendizado Profundo , Neoplasias Cutâneas , Humanos , Inteligência Artificial , Neoplasias Cutâneas/diagnóstico , Redes Neurais de Computação , Algoritmos
4.
J Nutr ; 154(1): 79-86, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37951389

RESUMO

BACKGROUND: Numerous research works have investigated the association between tea consumption and the risk of acute cerebrovascular events; however, the results are inconsistent. OBJECTIVES: We used Mendelian randomization (MR) to evaluate the causal association between tea intake and several acute cerebrovascular events, including any ischemic stroke, large atherosclerotic stroke (LAS), cardiogenic embolic stroke (CES), small vessel stroke (SVS), intracranial hemorrhage (ICH), and subarachnoid hemorrhage (SAH). METHODS: We obtained summary genome-wide association study (GWAS) data on tea intake and acute cerebrovascular events in populations of European ancestry. The GWAS on tea intake is derived from the UK Biobank, where we have chosen single-nucleotide polymorphisms (SNPs) closely associated with it as instrumental variables. We also obtained summary data on ischemic stroke from a GWAS meta-analysis, as well as summary data on ICH and SAH from the FinnGen study. We first explored the causal association between tea intake and several acute cerebrovascular events using univariate Mendelian randomization (UVMR), and then further assessed the causal association between tea intake and SVS using multivariate Mendelian randomization (MVMR) corrected for multiple confounders. RESULTS: In UVMR, genetically predicted increases in tea intake were linked to a lower risk of SVS (OR: 0.58; 95% CI: 0.39, 0.86). There was no causal association between tea intake and the risk of other acute cerebrovascular events. In the MVMR, our results show that there was still a significant causal association between drinking tea and SVS, after adjusting body mass index, total cholesterol, low-density lipoprotein cholesterol, diabetes, hypertension, smoking, and alcohol consumption. CONCLUSION: This MR study provides new genetic evidence that increased tea intake reduces the risk of SVS in the European population. However, possibly because of limited statistical power, the study did not find that tea consumption reduced the risk of several other acute cerebrovascular events.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Estudo de Associação Genômica Ampla , Acidente Vascular Cerebral/genética , LDL-Colesterol , Polimorfismo de Nucleotídeo Único , Chá , Análise da Randomização Mendeliana , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Pancreatology ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38763786

RESUMO

BACKGROUND & AIMS: Mutations in genes, including serine protease inhibitor Kazal-type 1 (SPINK1), influence disease progression following sentinel acute pancreatitis event (SAPE) attacks. SPINK1 c.194+2T > C intron mutation is one of the main mutants of SPINK1,which leads to the impairment of SPINK1 function by causing skipping of exon 3. Research on the pathogenesis of SAPE attacks would contribute to the understanding of the outcomes of acute pancreatitis. Therefore, the aim of the study was to clarify the role of SPINK1 c.194+2T > C mutation in the CP progression after an AP attack. METHODS: SAPE attacks were induced in wildtype and SPINK mutant (Spink1 c.194+2T > C) mice by cerulein injection. The mice were sacrificed at 24 h, 14 d, 28 d, and 42 d post-SAPE. Data-independent acquisition (DIA) proteomic analysis was performed for the identification of differentially expressed protein in the pancreatic tissues. Functional analyses were performed using THP-1 and HPSCs. RESULTS: Following SAPE attack, the Spink1 c.194+2T > C mutant mice exhibited a more severe acute pancreatitis phenotype within 24 h. In the chronic phase, the chronic pancreatitis phenotype was more severe in the Spink1 c.194+2T > C mutant mice after SAPE. Proteomic analysis revealed elevated IL-33 level in Spink1 c.194+2T > C mutant mice. Further in vitro analyses revealed that IL-33 induced M2 polarization of macrophages and activation of pancreatic stellate cells. CONCLUSION: Spink1 c.194+2T > C mutation plays an important role in the prognosis of patients following SAPE. Heterozygous Spink1 c.194+2T > C mutation promotes the development of chronic pancreatitis after an acute attack in mice through elevated IL-33 level and the induction of M2 polarization in coordination with pancreatic stellate cell activation.

6.
Environ Sci Technol ; 58(22): 9815-9827, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38768015

RESUMO

Tropical small island developing states (SIDS), with their geographical isolation and limited resources, heavily rely on the fisheries industry for food and revenue. The presence of marine lipophilic phycotoxins (MLPs) poses risks to their economy and human health. To understand the contamination status and potential risks, the Republic of Kiribati was selected as the representative tropical SIDS and 55 species of 256 coral reef fish encompassing multiple trophic levels and feeding strategies were collected to analyze 17 typical MLPs. Our results showed that the potential risks of ciguatoxins were the highest and approximately 62% of fish species may pose risks for consumers. Biomagnification of ciguatoxins was observed in the food web with a trophic magnification factor of 2.90. Brevetoxin-3, okadaic acid, and dinophysistoxin-1 and -2 were first reported, but the risks posed by okadaic acid and dinophysistoxins were found to be negligible. The correlation analysis revealed that fish body size and trophic position are unreliable metrics to indicate the associated risks and prevent the consumption of contaminated fish. The potential risks of MLPs in Kiribati are of concern, and our findings can serve as valuable inputs for developing food safety policies and fisheries management strategies specific to tropical SIDS contexts.


Assuntos
Peixes , Toxinas Marinhas , Animais , Cadeia Alimentar , Ilhas , Humanos , Medição de Risco , Clima Tropical , Ciguatoxinas/toxicidade
7.
Nutr Neurosci ; : 1-6, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347678

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a degenerative disease of the nervous system. Observational studies have found an association between plant food intake and AD. However, it is unclear whether this association is influenced by confounding factors. We aimed to explore the causal relationship between plant-based diet and the risk of AD using two-sample Mendelian randomization. MATERIALS AND METHODS: We obtained datasets of exposure from the IEU Open GWAS project, including dried fruit intake, fresh fruit intake, raw vegetable intake, cooked vegetable intake, and cereal intake. The summary data for AD were obtained from a large GWAS meta-analysis containing 71,880 cases and 383,378 controls. RESULTS: Increased intake of dried fruits was associated with a reduced risk of AD (IVW: OR = 0.88, 95CI = 0.82-0.95). No causal association was found between the intake of other foods and AD. CONCLUSION: This MR study suggests that genetically predicted increased intake of dried fruits is a causal protective factor for AD.

8.
Clin Exp Pharmacol Physiol ; 51(6): e13859, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38643975

RESUMO

Previous study has demonstrated that the Dietary Inflammation Index (DII) played a role in the risk of inflammatory bowel disease (IBD), however, the prevalence and risk factors for IBD are distinct across locations and groups, and therefore, the findings are debatable and warrant further investigation. A total of 4363 participants were calculated in the National Health and Nutrition Examination Survey (NHANES) 2009 to 2010, of whom 1.21% self-reported a history of IBD. DII values were performed as a good predictor of dietary inflammation based on data from two 24-h dietary reviews in the NHANES database. Comparing the multifarious effects along with variations of the whole population by grouping populations according to DII quartiles, dietary inflammation levels increased progressively from DII quartile 1(Q1) to quartile 4(Q4). The association between DII and IBD was tested with multi-variable logistic regression models, subgroup analyses and weighted generalized additive models. Participants in the Q4 group showed the highest levels of C-reactive protein and reduced haemoglobin and albumin levels. Logistic regression confirmed the odds ratios (95% confidence intervals) of IBD for DII were 0.99 (0.86, 1.15), 0.97 (0.84, 1.13) and 0.80 (0.66, 0.98) in models 1, 2 and 3, respectively. The negative correlation between DII and IBD among United States adults from the NHANES database became increasingly apparent as covariates were adjusted. Subgroup analyses and smoothed curve fitting confirmed the inverse results. The study revealed that DII was correlated with the overall physical well-being of participants. However, there was no significant association between DII and IBD.


Assuntos
Dieta , Inflamação , Doenças Inflamatórias Intestinais , Inquéritos Nutricionais , Humanos , Doenças Inflamatórias Intestinais/epidemiologia , Masculino , Feminino , Adulto , Inflamação/epidemiologia , Inflamação/sangue , Dieta/efeitos adversos , Pessoa de Meia-Idade , Fatores de Risco , Proteína C-Reativa/análise , Proteína C-Reativa/metabolismo , Estados Unidos/epidemiologia
9.
J Stroke Cerebrovasc Dis ; 33(7): 107737, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38688395

RESUMO

BACKGROUND: The association between hypothyroidism and stroke remains controversial and the association between hypothyroidism and stroke subtypes has not been satisfactorily researched. This study aimed to explore the causal effect of hypothyroidism on the risk of stroke and its subtypes by Mendelian randomization (MR) analysis. METHODS: Single nucleotide polymorphisms (SNPs) were selected from published genome-wide association studies (GWAS) meta-analysis as instrumental variables (IVs) for hypothyroidism. As outcomes, summary GWAS data for stroke and its subtypes were obtained from two other large GWAS meta-analyses, including any stroke (AS), any ischemic stroke (AIS), large vessel stroke (LAS), cardiogenic embolic stroke (CES), small vessel stroke (SVS), and intracranial hemorrhage (ICH). Univariate Mendelian randomization (UVMR) and multivariate Mendelian randomization (MVMR) were used to assess the causal effect of hypothyroidism on stroke and its subtypes. RESULTS: In UVMR, genetically predicted hypothyroidism was significantly associated with LAS (OR = 1.14, 95CI = 1.02-1.27) and SVS (OR = 1.14, 95CI = 1.04-1.25), but not with AS, AIS, CES, and ICH. The results of the MVMR showed that after adjusting for smoking, alcohol consumption, hypertension, diabetes, low-density lipoprotein cholesterol (LDL-c), and body mass index (BMI), the causal association between hypothyroidism and SVS remained significant, while the association between hypothyroidism and LAS became nonsignificant. CONCLUSION: Hypothyroidism is causally associated with risk for LAS and SVS, but not for other stroke subtypes. Hypothyroidism may be an independent risk factor for SVS, and vascular risk factors play an important role in hypothyroidism causing LAS.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Hipotireoidismo , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral , Humanos , Hipotireoidismo/genética , Hipotireoidismo/epidemiologia , Hipotireoidismo/diagnóstico , Fatores de Risco , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Medição de Risco , Fenótipo , AVC Isquêmico/genética , AVC Isquêmico/diagnóstico , AVC Isquêmico/epidemiologia , Feminino , AVC Embólico/genética , AVC Embólico/etiologia , AVC Embólico/diagnóstico , AVC Embólico/epidemiologia , Masculino
10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 43-48, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38433630

RESUMO

Objective To analyze the correlations between platelet-related parameters and the incidence of anxiety and depression in the patients undergoing peritoneal dialysis(PD),and evaluate the efficacy of the parameters in the diagnosis of anxiety and depression in PD patients. Methods A total of 245 patients undergoing PD in the First Affiliated Hospital of Hebei North University from September 2022 to February 2023 were enrolled.The generalized anxiety scale(GAD-7) and the patient health questionnaire(PHQ-9) were used to evaluate the anxiety and depression of the patients,respectively.The personal information and biochemical indicators of the patients were collected,and the platelet count(PLT),mean platelet volume(MPV),and platelet distribution width(PDW) were measured.Logistic regression was adopted to analyze the relationships of platelet-related parameters with anxiety and depression in PD patients. Results Among the 245 patients undergoing PD,the incidences of anxiety and depression were 15.9% and 38.0%,respectively.There were differences in the dialysis period(Z=-2.358,P=0.018;Z=-3.079,P=0.002),MPV(Z=-4.953,P<0.001;Z=-7.878,P<0.001),and PDW(Z=-4.587,P<0.001;Z=-7.367,P<0.001) between the anxiety group and the non-anxiety group as well as between the depression group and the non-depression group.The correlation analysis showed that MPV(r=0.358,P<0.001;r=0.489,P<0.001) and PDW(r=0.340,P<0.001;r=0.447,P<0.001) were positively correlated with anxiety and depression in the patients undergoing PD.The Logistic regression model showed that MPV(P=0.022,P=0.011),PDW(P=0.041,P=0.018),and dialysis period(P=0.011,P=0.030) were independent risk factors for the anxiety and depressive state in PD patients.The areas under the receiver operating characteristic curve of MPV in the diagnosis of anxiety and depression in PD patients were 0.750 and 0.800,respectively,and those of PDW were 0.732 and 0.780,respectively. Conclusion MPV and PDW have high efficacy in the diagnosis of anxiety and depression associated with PD and can be used as objective indicators to evaluate the anxiety and depression in the patients undergoing PD.


Assuntos
Ansiedade , Diálise Peritoneal , Humanos , Diálise Peritoneal/efeitos adversos , Hospitais , Modelos Logísticos , Curva ROC
11.
J Am Chem Soc ; 145(47): 25864-25873, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37971813

RESUMO

Optical gain of colloidal quantum dots (QDs) is often attained in the multiexciton regime, which strongly complicates their lasing applications as the gain lifetime is limited by nonradiative Auger recombination occurring typically on the picosecond time scale. In principle, low-threshold gain can be achieved if the gain-active emission has a sizable red shift compared to the absorption. But, this mechanism has been rarely observed in typical QDs featuring small Stokes shift due to their weak electron-phonon coupling. Here, we report the observation of sub-single-exciton gain in CsPbI3 and CsPbBr3 perovskite QDs, which is unequivocally established through pinpointing the stimulated emission and biexciton absorption signatures using polarization-controlled femtosecond transient absorption spectroscopy. The soft lattice of perovskite QDs and hence strong electron-phonon coupling lead to two stimulated emission features from free and self-trapped excitons, respectively. In monodisperse QDs of varying sizes, the Stokes shift of the self-trapped exciton emission is sufficiently large to overcome the biexciton absorption loss and the inhomogeneous line width, enabling optical gain with average exciton occupancy down to <10%.

12.
Am J Epidemiol ; 192(8): 1386-1395, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-36928091

RESUMO

In the Vaccine Safety Datalink (VSD), we previously reported no association between coronavirus disease 2019 (COVID-19) vaccination in early pregnancy and spontaneous abortion (SAB). The present study aims to understand how time since vaccine rollout or other methodological factors could affect results. Using a case-control design and generalized estimating equations, we estimated the odds ratios (ORs) of COVID-19 vaccination in the 28 days before a SAB or last date of the surveillance period (index date) in ongoing pregnancies and occurrence of SAB, across cumulative 4-week periods from December 2020 through June 2021. Using data from a single site, we evaluated alternative methodological approaches: increasing the exposure window to 42 days, modifying the index date from the last day to the midpoint of the surveillance period, and constructing a cohort design with a time-dependent exposure model. A protective effect (OR = 0.78, 95% confidence interval: 0.69, 0.89), observed with 3-cumulative periods ending March 8, 2021, was attenuated when surveillance extended to June 28, 2021 (OR = 1.02, 95% confidence interval: 0.96, 1.08). We observed a lower OR for a 42-day window compared with a 28-day window. The time-dependent model showed no association. Timing of the surveillance appears to be an important factor affecting the observed vaccine-SAB association.


Assuntos
Aborto Espontâneo , Vacinas contra COVID-19 , Feminino , Humanos , Gravidez , Aborto Espontâneo/induzido quimicamente , Aborto Espontâneo/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Estados Unidos/epidemiologia , Vacinação/efeitos adversos
13.
Plant Cell Environ ; 46(1): 171-184, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36324267

RESUMO

Precocious leaf senescence can reduce crop yield and quality by limiting the growth stage. Melatonin has been shown to delay leaf senescence; however, the underlying mechanism remains obscure. Here, we show that melatonin offsets abscisic acid (ABA) to protect photosystem II and delay the senescence of attached old leaves under the light. Melatonin induced H2 O2 accumulation accompanied by an upregulation of melon respiratory burst oxidase homolog D (CmRBOHD) under ABA-induced stress. Both melatonin and H2 O2 induced the accumulation of cytoplasmic-free Ca2+ ([Ca2+ ]cyt ) in response to ABA, while blocking of Ca2+ influx channels attenuated melatonin- and H2 O2 -induced ABA tolerance. CmRBOHD overexpression induced [Ca2+ ]cyt accumulation and delayed leaf senescence, whereas deletion of Arabidopsis AtRBOHD, a homologous gene of CmRBOHD, compromised the melatonin-induced [Ca2+ ]cyt accumulation and delay of leaf senescence in Arabidopsis under ABA stress. Furthermore, melatonin, H2 O2  and Ca2+ attenuated ABA-induced K+ efflux and subsequent cell death. CmRBOHD overexpression and AtRBOHD deletion alleviated and aggravated the ABA-induced K+ efflux, respectively. Taken together, our study unveils a new mechanism by which melatonin offsets ABA action to delay leaf senescence via RBOHD-dependent H2 O2 production that triggers [Ca2+ ]cyt accumulation and subsequently inhibits K+ efflux and delays cell death/leaf senescence in response to ABA.


Assuntos
Arabidopsis , Melatonina , Ácido Abscísico/farmacologia , Melatonina/farmacologia , Cálcio , Arabidopsis/genética , Senescência Vegetal
14.
Scand J Gastroenterol ; 58(1): 38-44, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35850581

RESUMO

OBJECTIVES: Limited literature exists on the characteristics of early gastric signet ring cell carcinoma (GSRCC) within 20 mm. This study aimed to explore this type of cancer from several aspects, to provide guidance for early detection and intervention of GSRCC. METHODS: We retrospectively collected data from 24 patients diagnosed with early GSRCC ≤20 mm in Beijing Friendship Hospital from 2016 to 2021. According to tumor size, those lesions were divided into three groups: diminutive group (1-5 mm, n = 4), small group (6-10 mm, n = 12) and intermediate group (11-20 mm, n = 8). The clinicopathologic and endoscopic characteristics of GSRCC were compared among the three groups. RESULTS: Treatment strategies for lesions differed according to the size (p<.05). There were no significant differences among the three groups with regard to age, sex, Helicobacter pylori infection, tumor location and macroscopic type. Lesions were often flat type and more likely to present with discoloration, uneven color, ulceration and submucosal invasion with the increase of diameter. Almost all cases showed abnormal intervening part (IP) under magnifying endoscopy. CONCLUSIONS: The location of early signet ring cell carcinoma is not specific, and the diminutive lesions are often flat. Abnormal IP may be the early endoscopic feature of early GSRCC.


Assuntos
Carcinoma de Células em Anel de Sinete , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Detecção Precoce de Câncer , Carcinoma de Células em Anel de Sinete/diagnóstico , Carcinoma de Células em Anel de Sinete/patologia , Neoplasias Gástricas/patologia , Endoscopia Gastrointestinal
15.
Inorg Chem ; 62(49): 20050-20061, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37989485

RESUMO

In this contribution, we rationally designed and controllably fabricated a NiMo/Al2O3-montmorillonite (3D-NiMo/Al2O3-MMT) monolithic catalyst via a 3D printing strategy with economical montmorillonite (MMT) as a binder. The catalytic performance of the resulting NiMo/Al2O3-MMT for 4,6-dimethyldibenzothiophene (4,6-DMDBT) hydrodesulfurization (HDS) was evaluated. The experimental results unveil that the 3D-NiMo/Al2O3-MMT monolithic catalyst exhibits robust stability and exceptional HDS activity with 99.2% 4,6-DMDBT conversion (residual 4 ppm of S), which is remarkably superior to that of conventional NiMo/Al2O3 (61.5%), NiMo/MMT (63.2%), and even NiMo/Al2O3-MMT (76.5%) prepared by the mechanical-mixing method. This should be ascribed to the synthetic effect between the MMT binder and the Al2O3 substrate, which effectively weakens the interaction between the Mo species and the Lewis acids on the original Al2O3 surface, thereby significantly increasing the content of reducible Mo species and considerably facilitating the formation of more highly active NiMoS phase (Type II) with optimal average stacking layers and thereafter remarkably enhancing the ultradeep HDS activity of the 3D-NiMo/Al2O3-MMT monolithic catalyst.

16.
Int J Mol Sci ; 24(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37446286

RESUMO

Tumor tissues often exhibit unique integrin receptor presentation during development, such as high exposures of αvß3 and αIIbß3 integrins. These features are not present in normal tissues. The induction of selective thrombosis and infarction in the tumor-feeding vessels, as well as specific antagonism of αvß3 integrin on the surface of tumor endothelial cells, is a potential novel antitumor strategy. The Echistatin-Annexin V (EAV) fusion protein is a novel Annexin V (ANV) derivative that possesses a high degree of αvß3 and αIIbß3 integrin receptor recognition and binding characteristics while retaining the specific binding ability of the natural ANV molecule for phosphatidylserine (PS). We systematically investigated the biological effects of this novel molecule with superimposed functions on mouse melanoma. We found that EAV inhibited the viability and migration of B16F10 murine melanoma cells in a dose-dependent manner, exhibited good tumor suppressive effects in a xenograft mouse melanoma model, strongly induced tumor tissue necrosis in mice, and targeted the inhibition of angiogenesis in mouse melanoma tumor tissue. EAV exhibited stronger biological effects than natural ANV molecules in inhibiting melanoma in mice. The unique biological effects of EAV are based on its high ß3-type integrin receptor-specific recognition and binding ability, as well as its highly selective binding to PS molecules. Based on these findings, we propose that EAV-mediated tumor suppression is a novel and promising antitumor strategy that targets both PS- and integrin ß3-positive tumor neovascularization and the tumor cells themselves, thus providing a possible mechanism for the treatment of melanoma.


Assuntos
Integrina beta3 , Melanoma , Humanos , Camundongos , Animais , Integrina beta3/metabolismo , Anexina A5/metabolismo , Células Endoteliais/metabolismo , Melanoma/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Integrina alfaVbeta3/metabolismo
17.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36835282

RESUMO

Malignant melanoma, an increasingly common form of skin cancer, is a major threat to public health, especially when the disease progresses past skin lesions to the stage of advanced metastasis. Targeted drug development is an effective strategy for the treatment of malignant melanoma. In this work, a new antimelanoma tumor peptide, the lebestatin-annexin V (designated LbtA5) fusion protein, was developed and synthesized by recombinant DNA techniques. As a control, annexin V (designated ANV) was also synthesized by the same method. The fusion protein combines annexin V, which specifically recognizes and binds phosphatidylserine, with the disintegrin lebestatin (lbt), a polypeptide that specifically recognizes and binds integrin α1ß1. LbtA5 was successfully prepared with good stability and high purity while retaining the dual biological activity of ANV and lbt. MTT assays demonstrated that both ANV and LbtA5 could reduce the viability of melanoma B16F10 cells, but the activity of the fusion protein LbtA5 was superior to that of ANV. The tumor volume growth was slowed in a mouse xenograft model treated with ANV and LbtA5, and the inhibitory effect of high concentrations of LbtA5 was significantly better than that of the same dose of ANV and was comparable to that of DTIC, a drug used clinically for melanoma treatment. The hematoxylin and eosin (H&E) staining test showed that ANV and LbtA5 had antitumor effects, but LbtA5 showed a stronger ability to induce melanoma necrosis in mice. Immunohistochemical experiments further showed that ANV and LbtA5 may inhibit tumor growth by inhibiting angiogenesis in tumor tissue. Fluorescence labeling experiments showed that the fusion of ANV with lbt enhanced the targeting of LbtA5 to mouse melanoma tumor tissue, and the amount of target protein in tumor tissue was significantly increased. In conclusion, effective coupling of the integrin α1ß1-specific recognition molecule lbt confers stronger biological antimelanoma effects of ANV, which may be achieved by the dual effects of effective inhibition of B16F10 melanoma cell viability and inhibition of tumor tissue angiogenesis. The present study describes a new potential strategy for the application of the promising recombinant fusion protein LbtA5 in the treatment of various cancers, including malignant melanoma.


Assuntos
Anexina A5 , Integrina alfa1beta1 , Melanoma , Proteínas Recombinantes de Fusão , Neoplasias Cutâneas , Animais , Humanos , Camundongos , Anexina A5/uso terapêutico , Integrina alfa1beta1/metabolismo , Melanoma/terapia , Proteínas Recombinantes de Fusão/uso terapêutico , Neoplasias Cutâneas/terapia , Melanoma Experimental , Melanoma Maligno Cutâneo
18.
J Environ Manage ; 330: 117164, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36603256

RESUMO

pH is one of the major parameters that influence the granulation and long-term operation of aerobic granular sludge (AGS). In hypersaline wastewater, the impact of pH on granulation and the extent of organic loading rate (OLR) that AGS can withstand under different pH are still not clear. In this study, AGS was cultivated at 3% salinity in three sequencing batch reactors with influent pH values of 5.0, 7.0, and 9.0, respectively, and the OLR was stepwise increased from 2.4 to 16.8 kg COD/m3·d after the granules maturation. The results showed the satisfactory granulation and organic removal under different influent pH conditions, in which the granulation was completed on day 43, 23, and 23, respectively. Neutral influent was the most appropriate for development of salt-tolerant aerobic granular sludge (SAGS), while acidic environment induced the formation of fluffy filamentous granules, and alkaline environment weakened the granule stability. Metagenomic analysis revealed the similar microbial community of neutral and alkaline conditions, with the predominance of genus Paracoccus_f__Rhodobacteraceae. While in acidic environment, fungus Fusarium formed the skeleton of filamentous granules and functioned as the carrier of bacteria including Azoarcus and Pararhodobacter. With the elevation of OLR, SAGSs were found to maintain the compact structure under OLRs of 2.4, 7.2, and 2.4 kg COD/m3·d, and obtain high TOC removal (>95.0%) under OLRs of 7.2, 14.4, and 14.4 kg COD/m3·d, respectively. For hypersaline high-strength organic wastewater, satisfactory TOC removal could also be obtained at broad pH ranges (5.0-9.0), in which neutral environment was the most suitable and acidic environment was the worst. This study contributed to a better understanding of SAGS granulation and treatment of hypersaline high-strength organic wastewater with different pH values.


Assuntos
Esgotos , Águas Residuárias , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Aerobiose , Reatores Biológicos/microbiologia , Concentração de Íons de Hidrogênio
19.
J Am Chem Soc ; 144(42): 19372-19381, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36240390

RESUMO

In contrast to regular J- and H-aggregates, thin film squaraine aggregates usually have broad absorption spectra containing both J-and H-like features, which are favorable for organic photovoltaics. Despite being successfully applied in organic photovoltaics for years, a clear interpretation of these optical properties by relating them to specific excited states and an underlying aggregate structure has not been made. In this work, by static and transient absorption spectroscopy on aggregated n-butyl anilino squaraines, we provide evidence that both the red- and blue-shifted peaks can be explained by assuming an ensemble of aggregates with intermolecular dipole-dipole resonance interactions and structural disorder deriving from the four different nearest neighbor alignments─in sharp contrast to previous association of the peaks with intermolecular charge-transfer interactions. In our model, the next-nearest neighbor dipole-dipole interactions may be negative or positive, which leads to the occurrence of J- and H-like features in the absorption spectrum. Upon femtosecond pulse excitation of the aggregated sample, a transient absorption spectrum deviating from the absorbance spectrum emerges. The deviation finds its origin in the excitation of two-exciton states by the probe pulse. The lifetime of the exciton is confirmed by the band integral dynamics, featuring a single-exponential decay with a lifetime of 205 ps. Our results disclose the aggregated structure and the origin of red- and blue-shifted peaks and explain the absence of photoluminescence in squaraine thin films. Our findings underline the important role of structural disorder of molecular aggregates for photovoltaic applications.


Assuntos
Ciclobutanos , Análise Espectral , Vibração , Fenóis
20.
Exp Eye Res ; 219: 109053, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35351462

RESUMO

PURPOSE: Dry eye syndrome (DES) is a multifactorial ocular disorder. The possible pathogens and pathogenic mechanisms for virus-related dry eye disease are largely unknown. The current study aimed to provide evidence for mechanisms contributing to DES induced by herpes simplex virus (HSV) infection in the harderian gland (HG) and lacrimal gland (LG). METHODS: We recorded the dry eye-like cornea pathology of irf3-/- mice infected with HSV-1 till 8 months of age. The slit-lamp and confocal microscopy was used to observe the corneal defects. TUNEL was used to detect the corneal apoptosis. Human corneas suffered from herpes stromal keratitis (HSK) were also analyzed as a comparison. Then, we measure the aqueous tear production with a phenol red thread test in irf3-/-mice, and recorded their tear film breakup time. HGs and LGs were sectioned and analyzed using HE and oil-red-O staining. For molecular signaling pathway analysis, we used mRNA sequencing to explore the related gene ontology. Western blotting (WB) and real-time reverse transcription-quantitative polymerase chain reaction were used to verify the level of the Akt signaling pathway and related inflammatory factors. RESULTS: Inoculated irf3-/- mice tended to develop dry eye-like symptoms, such as corneal keratinization, corneal cell apoptosis, and tear reduction. The HGs and LGs of irf3-/- mice showed increased level of HSV-1, and exhibited inflammatory pathological changes and impaired function, which explained the damaged tear film. WB and mRNA sequencing indicated that enhanced PI3K-Akt pathway in irf3-/- mice might account for the higher susceptibility to HSV infection. CONCLUSIONS: We observed evidence of DES in irf3-/- mice induced by HSV-1 infection in the HGs and LGs, which may introduce a potential novel target for DES treatment.


Assuntos
Síndromes do Olho Seco , Glândula de Harder , Herpes Simples , Herpesvirus Humano 1 , Ceratite Herpética , Aparelho Lacrimal , Animais , Córnea/metabolismo , Modelos Animais de Doenças , Síndromes do Olho Seco/metabolismo , Glândula de Harder/metabolismo , Glândula de Harder/patologia , Herpes Simples/metabolismo , Herpes Simples/patologia , Fator Regulador 3 de Interferon/metabolismo , Aparelho Lacrimal/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo
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