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2.
Cell ; 171(7): 1559-1572.e20, 2017 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-29245011

RESUMO

Large-scale transcriptome sequencing efforts have vastly expanded the catalog of long non-coding RNAs (lncRNAs) with varying evolutionary conservation, lineage expression, and cancer specificity. Here, we functionally characterize a novel ultraconserved lncRNA, THOR (ENSG00000226856), which exhibits expression exclusively in testis and a broad range of human cancers. THOR knockdown and overexpression in multiple cell lines and animal models alters cell or tumor growth supporting an oncogenic role. We discovered a conserved interaction of THOR with IGF2BP1 and show that THOR contributes to the mRNA stabilization activities of IGF2BP1. Notably, transgenic THOR knockout produced fertilization defects in zebrafish and also conferred a resistance to melanoma onset. Likewise, ectopic expression of human THOR in zebrafish accelerated the onset of melanoma. THOR represents a novel class of functionally important cancer/testis lncRNAs whose structure and function have undergone positive evolutionary selection.


Assuntos
Modelos Animais de Doenças , Melanoma/metabolismo , RNA Longo não Codificante/metabolismo , Peixe-Zebra , Animais , Linhagem Celular Tumoral , Técnicas de Inativação de Genes , Humanos , Masculino , Camundongos , Proteínas de Ligação a RNA/metabolismo , Testículo/metabolismo
3.
Nature ; 601(7893): 434-439, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34937944

RESUMO

The switch/sucrose non-fermentable (SWI/SNF) complex has a crucial role in chromatin remodelling1 and is altered in over 20% of cancers2,3. Here we developed a proteolysis-targeting chimera (PROTAC) degrader of the SWI/SNF ATPase subunits, SMARCA2 and SMARCA4, called AU-15330. Androgen receptor (AR)+ forkhead box A1 (FOXA1)+ prostate cancer cells are exquisitely sensitive to dual SMARCA2 and SMARCA4 degradation relative to normal and other cancer cell lines. SWI/SNF ATPase degradation rapidly compacts cis-regulatory elements bound by transcription factors that drive prostate cancer cell proliferation, namely AR, FOXA1, ERG and MYC, which dislodges them from chromatin, disables their core enhancer circuitry, and abolishes the downstream oncogenic gene programs. SWI/SNF ATPase degradation also disrupts super-enhancer and promoter looping interactions that wire supra-physiologic expression of the AR, FOXA1 and MYC oncogenes themselves. AU-15330 induces potent inhibition of tumour growth in xenograft models of prostate cancer and synergizes with the AR antagonist enzalutamide, even inducing disease remission in castration-resistant prostate cancer (CRPC) models without toxicity. Thus, impeding SWI/SNF-mediated enhancer accessibility represents a promising therapeutic approach for enhancer-addicted cancers.


Assuntos
Adenosina Trifosfatases , DNA Helicases , Proteínas Nucleares , Neoplasias da Próstata , Fatores de Transcrição , Adenosina Trifosfatases/metabolismo , Animais , Benzamidas , DNA Helicases/genética , Elementos Facilitadores Genéticos , Genes myc , Fator 3-alfa Nuclear de Hepatócito , Humanos , Masculino , Nitrilas , Proteínas Nucleares/genética , Oncogenes , Feniltioidantoína , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Receptores Androgênicos , Fatores de Transcrição/genética , Regulador Transcricional ERG , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Proc Natl Acad Sci U S A ; 121(15): e2322563121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557192

RESUMO

Mammalian switch/sucrose nonfermentable (mSWI/SNF) ATPase degraders have been shown to be effective in enhancer-driven cancers by functioning to impede oncogenic transcription factor chromatin accessibility. Here, we developed AU-24118, an orally bioavailable proteolysis-targeting chimera (PROTAC) degrader of mSWI/SNF ATPases (SMARCA2 and SMARCA4) and PBRM1. AU-24118 demonstrated tumor regression in a model of castration-resistant prostate cancer (CRPC) which was further enhanced with combination enzalutamide treatment, a standard of care androgen receptor (AR) antagonist used in CRPC patients. Importantly, AU-24118 exhibited favorable pharmacokinetic profiles in preclinical analyses in mice and rats, and further toxicity testing in mice showed a favorable safety profile. As acquired resistance is common with targeted cancer therapeutics, experiments were designed to explore potential mechanisms of resistance that may arise with long-term mSWI/SNF ATPase PROTAC treatment. Prostate cancer cell lines exposed to long-term treatment with high doses of a mSWI/SNF ATPase degrader developed SMARCA4 bromodomain mutations and ABCB1 (ATP binding cassette subfamily B member 1) overexpression as acquired mechanisms of resistance. Intriguingly, while SMARCA4 mutations provided specific resistance to mSWI/SNF degraders, ABCB1 overexpression provided broader resistance to other potent PROTAC degraders targeting bromodomain-containing protein 4 and AR. The ABCB1 inhibitor, zosuquidar, reversed resistance to all three PROTAC degraders tested. Combined, these findings position mSWI/SNF degraders for clinical translation for patients with enhancer-driven cancers and define strategies to overcome resistance mechanisms that may arise.


Assuntos
Adenosina Trifosfatases , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Ratos , Camundongos , Animais , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Linhagem Celular , Cromatina , Mamíferos/genética , Antagonistas de Receptores de Andrógenos , DNA Helicases/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética
5.
Proc Natl Acad Sci U S A ; 120(30): e2221809120, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37459541

RESUMO

Early in the COVID-19 pandemic, data suggested that males had a higher risk of developing severe disease and that androgen deprivation therapy might be associated with protection. Combined with the fact that TMPRSS2 (transmembrane serine protease 2), a host entry factor for the SARS-CoV-2 virus, was a well-known androgen-regulated gene, this led to an upsurge of research investigating androgen receptor (AR)-targeting drugs. Proxalutamide, an AR antagonist, was shown in initial clinical studies to benefit COVID-19 patients; however, further validation is needed as one study was retracted. Due to continued interest in proxalutamide, which is in phase 3 trials, we examined its ability to impact SARS-CoV-2 infection and downstream inflammatory responses. Proxalutamide exerted similar effects as enzalutamide, an AR antagonist prescribed for advanced prostate cancer, in decreasing AR signaling and expression of TMPRSS2 and angiotensin-converting enzyme 2 (ACE2), the SARS-CoV-2 receptor. However, proxalutamide led to degradation of AR protein, which was not observed with enzalutamide. Proxalutamide inhibited SARS-CoV-2 infection with an IC50 value of 97 nM, compared to 281 nM for enzalutamide. Importantly, proxalutamide inhibited infection by multiple SARS-CoV-2 variants and synergized with remdesivir. Proxalutamide protected against cell death in response to tumor necrosis factor alpha and interferon gamma, and overall survival of mice was increased with proxalutamide treatment prior to cytokine exposure. Mechanistically, we found that proxalutamide increased levels of NRF2, an essential transcription factor that mediates antioxidant responses, and decreased lung inflammation. These data provide compelling evidence that proxalutamide can prevent SARS-CoV-2 infection and cytokine-induced lung damage, suggesting that promising clinical data may emerge from ongoing phase 3 trials.


Assuntos
COVID-19 , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , SARS-CoV-2/metabolismo , Androgênios , Antagonistas de Androgênios/uso terapêutico , Pandemias , Peptidil Dipeptidase A/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Interferon gama/uso terapêutico
6.
Proc Natl Acad Sci U S A ; 120(49): e2314416120, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38011559

RESUMO

Despite the remarkable clinical success of immunotherapies in a subset of cancer patients, many fail to respond to treatment and exhibit resistance. Here, we found that genetic or pharmacologic inhibition of the lipid kinase PIKfyve, a regulator of autophagic flux and lysosomal biogenesis, upregulated surface expression of major histocompatibility complex class I (MHC-I) in cancer cells via impairing autophagic flux, resulting in enhanced cancer cell killing mediated by CD8+ T cells. Genetic depletion or pharmacologic inhibition of PIKfyve elevated tumor-specific MHC-I surface expression, increased intratumoral functional CD8+ T cells, and slowed tumor progression in multiple syngeneic mouse models. Importantly, enhanced antitumor responses by Pikfyve-depletion were CD8+ T cell- and MHC-I-dependent, as CD8+ T cell depletion or B2m knockout rescued tumor growth. Furthermore, PIKfyve inhibition improved response to immune checkpoint blockade (ICB), adoptive cell therapy, and a therapeutic vaccine. High expression of PIKFYVE was also predictive of poor response to ICB and prognostic of poor survival in ICB-treated cohorts. Collectively, our findings show that targeting PIKfyve enhances immunotherapies by elevating surface expression of MHC-I in cancer cells, and PIKfyve inhibitors have potential as agents to increase immunotherapy response in cancer patients.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Camundongos , Animais , Humanos , Genes MHC Classe I , Antígenos de Histocompatibilidade Classe I , Imunoterapia/métodos , Lipídeos , Neoplasias/genética , Neoplasias/terapia
8.
Invest New Drugs ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227508

RESUMO

ESK981 is a potent tyrosine kinase and PIKfyve lipid kinase inhibitor. This phase II trial evaluated the efficacy of ESK981 as a single agent in patients with androgen receptor-positive (AR +) metastatic castration-resistant prostate cancer (mCRPC). Eligible patients had mCRPC with progression on AR-targeted agents and without prior chemotherapy treatment. Each patient received 160 mg ESK981 once daily for 5 days per week for 4 weeks per cycle (except for an adverse event (AE) occurrence). The primary endpoints were a 50% reduction in prostate-specific antigen (PSA50), and safety. Secondary endpoints included the time and the duration of PSA response, PSA progression rates, PSA progression free survival (PFS) and overall survival (OS). Exploratory investigations included whole exome sequencing in patients before treatment, and morphological evaluation of biopsy samples pre- and post-treatment. PSA was evaluated in 13 patients. Only one patient (7.7% two-sided 95% Wilson CI (0.4%, 33.3%)) experienced a reduction in their PSA levels by 50% or more. The most common grade 3 treatment-related AEs were cardiac disorders, diarrhea, hypertension, alanine transaminase and aspartate transaminase elevations. No grade 4-5 events occurred. Median PFS was 1.8 months, and median OS was 12.1 months. Peripheral immune cells showed increased T cell activation and cytokine production in two patients who received 12-weeks of ESK981. Although relatively well tolerated, ESK981 alone showed no anti-tumor activity in patients with AR + mCRPC and its further evaluation as a single agent in AR + mCRPC is not warranted. (Trial registration: ClinicalTrials.gov, NCT03456804. Registration date: March 7, 2018).

9.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34413211

RESUMO

The global spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the associated disease COVID-19, requires therapeutic interventions that can be rapidly identified and translated to clinical care. Traditional drug discovery methods have a >90% failure rate and can take 10 to 15 y from target identification to clinical use. In contrast, drug repurposing can significantly accelerate translation. We developed a quantitative high-throughput screen to identify efficacious agents against SARS-CoV-2. From a library of 1,425 US Food and Drug Administration (FDA)-approved compounds and clinical candidates, we identified 17 hits that inhibited SARS-CoV-2 infection and analyzed their antiviral activity across multiple cell lines, including lymph node carcinoma of the prostate (LNCaP) cells and a physiologically relevant model of alveolar epithelial type 2 cells (iAEC2s). Additionally, we found that inhibitors of the Ras/Raf/MEK/ERK signaling pathway exacerbate SARS-CoV-2 infection in vitro. Notably, we discovered that lactoferrin, a glycoprotein found in secretory fluids including mammalian milk, inhibits SARS-CoV-2 infection in the nanomolar range in all cell models with multiple modes of action, including blockage of virus attachment to cellular heparan sulfate and enhancement of interferon responses. Given its safety profile, lactoferrin is a readily translatable therapeutic option for the management of COVID-19.


Assuntos
Antivirais/farmacologia , Fatores Imunológicos/farmacologia , Lactoferrina/farmacologia , SARS-CoV-2/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Células CACO-2 , Linhagem Celular Tumoral , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Descoberta de Drogas , Reposicionamento de Medicamentos/métodos , Células Epiteliais , Heparitina Sulfato/antagonistas & inibidores , Heparitina Sulfato/imunologia , Heparitina Sulfato/metabolismo , Hepatócitos , Ensaios de Triagem em Larga Escala , Humanos , SARS-CoV-2/crescimento & desenvolvimento , SARS-CoV-2/patogenicidade , Células Vero , Tratamento Farmacológico da COVID-19
10.
Proc Natl Acad Sci U S A ; 118(1): e2021450118, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33310900

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, employs two key host proteins to gain entry and replicate within cells, angiotensin-converting enzyme 2 (ACE2) and the cell surface transmembrane protease serine 2 (TMPRSS2). TMPRSS2 was first characterized as an androgen-regulated gene in the prostate. Supporting a role for sex hormones, males relative to females are disproportionately affected by COVID-19 in terms of mortality and morbidity. Several studies, including one employing a large epidemiological cohort, suggested that blocking androgen signaling is protective against COVID-19. Here, we demonstrate that androgens regulate the expression of ACE2, TMPRSS2, and androgen receptor (AR) in subsets of lung epithelial cells. AR levels are markedly elevated in males relative to females greater than 70 y of age. In males greater than 70 y old, smoking was associated with elevated levels of AR and ACE2 in lung epithelial cells. Transcriptional repression of the AR enhanceosome with AR or bromodomain and extraterminal domain (BET) antagonists inhibited SARS-CoV-2 infection in vitro. Taken together, these studies support further investigation of transcriptional inhibition of critical host factors in the treatment or prevention of COVID-19.

11.
Neurol Sci ; 44(10): 3615-3627, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37162664

RESUMO

OBJECTIVE: To develop and validate a machine learning (ML)-based model to predict functional outcome in Chinese patients with intracerebral hemorrhage (ICH). METHODS: This retrospective cohort study enrolled patients with ICH between November 2017 and November 2020. The follow-up period ended in February 2021. The study population was divided into training and testing sets with a ratio of 7:3. All variables were included in the least absolute shrinkage and selection operator (LASSO) regression for feature selection. The selected variables were incorporated into the random forest algorithm to construct the prediction model. The predictive performance of the model was evaluated via the area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and calibration curve. RESULTS: A total of 412 ICH patients were included, with 288 in the training set, and 124 in the testing set. Twelve attributes were selected: neurological deterioration, Glasgow Coma Scale (GCS) score at 24 h, baseline GCS score, time from onset to the emergency room, blood glucose, diastolic blood pressure (DBP) change in 24 h, hematoma volume change in 24 h, systemic immune-inflammatory index (SII), systolic blood pressure (SBP) change in 24 h, serum creatinine, serum sodium, and age. In the testing set, the accuracy, AUC, sensitivity, specificity, PPV, and NPV of the model were 0.895, 0.964, 0.872, 0.906, 0.810, and 0.939, respectively. The calibration curves showed a good calibration capability of the model. CONCLUSION: This developed random forest model performed well in predicting 3-month poor functional outcome for Chinese ICH patients.


Assuntos
Hemorragia Cerebral , Algoritmo Florestas Aleatórias , Humanos , Estudos Retrospectivos , Hemorragia Cerebral/diagnóstico , Valor Preditivo dos Testes , Hematoma
12.
Inorg Chem ; 61(42): 16528-16532, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36239584

RESUMO

A novel telluroniobate, K8Na6H7{[Co(en)2(SO3)][Te4Nb24O79]}·42H2O (en = ethylenediamine), has been synthesized through a diffusion strategy. It consists of a heteropolyoxoniobate [B-ß-TeNb9O33]17- cluster and isopolyoxoniobate {Nb7O22} building blocks. In addition, its structure was fully characterized by a series of spectroscopic methods. Furthermore, it exhibits an efficient catalytic performance in the transesterification of ethylene carbonate and methanol to prepare dimethyl carbonate with good catalytic reusability. Also, it demonstrates interesting proton conduction properties, with conductivity achieved at 3.05 × 10-4 S cm-1 (60 °C, 75% relative humidity).

13.
Phys Chem Chem Phys ; 23(1): 617-627, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33331372

RESUMO

The entire reaction mechanism of the dry reforming of methane (DRM) as well as the competition processes over perfect and boron-vacancy-containing h-BN sheet-supported Ni-catalysts (labeled Ni2/h-BN and Ni2/h-BN-B-D) was studied by density functional theory calculations in the present work. Our calculation results show that B-defected h-BN strongly binds to the Ni2 active sites (i.e., shows a strong metal-support interaction (SMSI) character) due to the better electron transfer between Ni2 sites and the support. It was found that CH4 is easier to activate than molecular CO2. The activation of CO2 occurs on the surface of Ni2/h-BN through a direct route, whereas it is prone to follow a hydrogen-assisted path for Ni2/h-BN-B-D via the COOH* intermediate, and the results show that the oxidant O* is easily formed on the surface of Ni2/h-BN-B-D. It was also found that O* is the main oxidant agent for CHx* intermediates through the CH3-O oxidation mechanism. The reaction kinetic analysis indicated that the reverse water gas shift reaction (RWGS) is much more favorable than DRM (1.30 vs. 1.72 eV) over the Ni2/h-BN system, whereas the RWGS and DRM are comparable on Ni2/h-BN-B-D (1.77 vs. 1.66 eV), suggesting a high DRM activity on Ni2/h-BN-B-D. Moreover, neither methane cracking nor a Boudouard reaction to form C* species is thermodynamically and kinetically unfavorable over Ni2/h-BN-B-D; hence, Ni2/h-BN-B-D has strong resistance to carbon deposition. Compared to Ni(111), both Ni2/h-BN-B-D and Ni2/h-BN show strong resistance to carbon deposition. Our results provide a further mechanistic understanding of the DRM over an Ni-based catalyst through the SMSI characteristic and the SMSI favors strong resistance to carbon deposition.

14.
Inorg Chem ; 59(12): 7895-7899, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32496063

RESUMO

A new organic-inorganic hybrid heteropolyoxoniobate, [{Cu(en)(H2O)4}{Cu(en)2(H2O)}{Cu(en)2(H2O)2}]1.5[H8SiTe8Nb15O64]·6H2O (1; en = ethanediamine), has been successfully synthesized by a conventional method. The compound was directed by pairs of [TeO3]2-/[SiO3]2- ions, generating two novel {TeNb9} and {SiTeNb6} subunits in situ owing to the mixed heteroanion. In addition, the solution behavior of compound 1 was investigated.

15.
Inorg Chem ; 59(3): 1967-1972, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31940183

RESUMO

A novel polyoxoniobate cluster directed by AsO33-, {[Cu(phen)]5[Nb6O19][As2Nb6O22]}2 (1a), has been successfully synthesized by a "two-pot" strategy, namely, the conventional aqueous solution and diffusional methods. It incorporates two {[Cu(phen)]2Nb6O19} and two {[Cu(phen)]3As2Nb6O22} subunits. Surprisingly, by changing the reaction conditions, one of the subunits {[Cu(phen)]2Nb6O19} was isolated as a guanidinium salt. These architectures were structurally characterized by single crystal X-ray diffraction, TGA, IR, elemental analysis and PXRD, etc. Furthermore, the behavior of 1 in aqueous solution was measured by electrospray ionization mass spectrometry, and the magnetic property in the low temperature range indicates the presence of antiferromagnetic interactions.

16.
Sensors (Basel) ; 20(9)2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32344855

RESUMO

Vehicle evaluation parameters, which are increasingly of concern for governments and consumers, quantify performance indicators, such as vehicle performance, emissions, and driving experience to help guide consumers in purchasing cars. While past approaches for driving cycle prediction have been proven effective and used in many countries, these algorithms are difficult to use in China with its complex traffic environment and increasingly high frequency of traffic jams. Meanwhile, we found that the vehicle dataset used by the driving cycle prediction problem is usually unbalanced in real cases, which means that there are more medium and high speed samples and very few samples at low and ultra-high speeds. If the ordinary clustering algorithm is directly applied to the unbalanced data, it will have a huge impact on the performance to build driving cycle maps, and the parameters of the map will deviate considerable from actual ones. In order to address these issues, this paper propose a novel driving cycle map algorithm framework based on an ensemble learning method named multi-clustering algorithm, to improve the performance of traditional clustering algorithms on unbalanced data sets. It is noteworthy that our model framework can be easily extended to other complicated structure areas due to its flexible modular design and parameter configuration. Finally, we tested our method based on actual traffic data generated in Fujian Province in China. The results prove the multi-clustering algorithm has excellent performance on our dataset.

17.
Int J Cancer ; 145(2): 415-426, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30628724

RESUMO

Polycomb group proteins are important epigenetic regulators for cell proliferation and differentiation, organ development, as well as initiation and progression of lethal diseases, including cancer. Upregulated Polycomb group proteins, including Enhancer of zeste homolog 2 (EZH2), promote proliferation, migration, invasion and metastasis of cancer cells, as well as self-renewal of cancer stem cells. In our study, we report that EZH2 and embryonic ectoderm development (EED) indicate respective direct interaction with androgen receptor (AR). In the context of AR-positive prostate cancer, EZH2 and EED regulate AR expression levels and AR downstream targets. More importantly, we demonstrate that targeting EZH2 with the small-molecule inhibitor astemizole in cancer significantly represses the EZH2 and AR expression as well as the neoplastic capacities. These results collectively suggest that pharmacologically targeting EZH2 might be a promising strategy for advanced prostate cancer.


Assuntos
Astemizol/administração & dosagem , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Animais , Astemizol/farmacologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/genética , Análise de Sequência de RNA , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Inorg Chem ; 58(19): 13030-13036, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31518117

RESUMO

Eight novel lanthanide-containing polyoxotantalates, Cs3[Ln(H2O)6{H4(TaO2)6As4O24}]·7H2O (Ln = Sm (1), Eu (2), Tb (3), Dy (4), Er (5), Tm (6), Yb (7), Lu (8)), have been obtained via a one-pot reaction methodology. Each of these compounds is made up of the new type polyanion [(TaO2)6As4O24]10- with Ln3+ linkers, giving a one-dimensional chain. The compounds represent the first family of "pure" Ta-based polyoxometalate lanthanide derivatives. These architectures were characterized by various physicochemical analyses. Furthermore, the photoluminescence properties of compounds 2-Eu and 8-Lu were also explored, and meanwhile time-resolved emission spectroscopy indicated that the {As4Ta6} segment makes a contribution to the energy transfer of compound 2 from the polyoxotantalate to the EuIII center, which efficiently facilitates emissions of the Eu3+ center.

19.
Clin Lab ; 65(7)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31307159

RESUMO

BACKGROUND: Recently, many broadly applicable and potent neutralizing antibodies have been screened from HIV-1-infected patients. However, all these effective neutralizing antibodies were isolated from patients naive to anti-retroviral treatment (ART). METHODS: To better understand the induction of neutralizing antibodies in patients on ART, we screened 3 patients with an over ten-year infection history on ART from 350 patients in China for a cross-reactive neutralizing antibody response based on the use of different antigens and recombinant viruses. We studied the evolution of neutralizing activity in two patients during a one-year period with previously described recombinant viruses NL4-3 and SF162 using ELISA and neutralization assays. RESULTS: Antibodies purified from sera were able to react with recombinant virus antigens R2-gp120 and SF162-gp140 and neutralize SF162 recombinant virus but not NL4-3 recombinant virus. In addition, we observed a significant increase in the neutralizing response of immunoglobulin G (IgG) isolated from the serum sample in Patient 1 and compared it with the serum from Patient 1 six months ago. CONCLUSIONS: We thus confirm the possibility of production of neutralizing antibodies in patients infected for over ten years on ART, and it is possible over time of the improvement of HIV-1 potent neutralizing activity associated with viremia and immune reconstruction.


Assuntos
Antirretrovirais/uso terapêutico , Anticorpos Neutralizantes/imunologia , Terapia Antirretroviral de Alta Atividade , Anticorpos Anti-HIV/imunologia , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Antirretrovirais/imunologia , Anticorpos Neutralizantes/sangue , Contagem de Linfócito CD4 , Reações Cruzadas/imunologia , Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , HIV-1/fisiologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Viremia/tratamento farmacológico , Viremia/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia
20.
J Therm Biol ; 76: 29-37, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30143294

RESUMO

The treatment of hypothermia suffered by naval fighters owing to seawater immersion has been a focus of research in recent years. Currently, the treatment of hypothermia in China is limited to external rewarming, which is of low efficiency and is not effective for patients suffering moderate to severe hypothermia. We thus proposed a vascular interventional heating method which directly heats the blood flow via a minimally invasive heating needle for rewarming. And a numerical simulation using a compartment model based on finite difference method was conducted. A set of whole body heating treatment simulation was also developed. Appropriate treatment parameters and procedures can be set and adjusted based on patient physical parameters. Here temperature response curves of different heating modes were obtained and analyzed. It was demonstrated that the desired thermal response can be achieved by adjusting the heating power and heating time, ensuring controllable accuracy in the treatment of patients with severe hypothermia. The proposed treatment for hypothermia is a new and effective alternative, and further progress is expected in clinical trials.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Hipotermia/terapia , Modelos Biológicos , Reaquecimento/instrumentação , Reaquecimento/métodos , Temperatura Corporal , Humanos
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