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1.
Eur J Med Chem ; 270: 116366, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581730

RESUMO

Inhibition of MDM2/p53 interaction with small-molecule inhibitors stabilizes p53 from MDM2 mediated degradation, which is a promising strategy for the treatment of cancer. In this report, a novel series of 4-imidazolidinone-containing compounds have been synthesized and tested in MDM2/p53 and MDM4/p53 FP binding assays. Upon SAR studies, compounds 2 (TB114) and 22 were identified as the most potent inhibitors of MDM2/p53 but not MDM4/p53 interactions. Both 2 and 22 exhibited strong antiproliferative activities in HCT-116 and MOLM-13 cell lines harboring wild type p53. Mechanistic studies show that 2 and 22 dose-dependently activated p53 and its target genes and induced apoptosis in cells based on the Western blot, qPCR, and flow cytometry assays. In addition, the antiproliferative activities of 2 and 22 were dependent on wild type p53, while they were not toxic to HEK-293 kidney cells. Furthermore, the on-target activities of 2 were general and applicable to other cancer cell lines with wild type p53. These attributes make 2 a good candidate for future optimization to discover a potential treatment of wild-type p53 cancer.


Assuntos
Antineoplásicos , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Células HEK293 , Linhagem Celular Tumoral , Apoptose , Antineoplásicos/farmacologia , Antineoplásicos/química , Proteínas Proto-Oncogênicas/metabolismo , Proteínas de Ciclo Celular/metabolismo
2.
Molecules ; 29(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38398498

RESUMO

Platinum-based drugs are widely used in chemotherapy for various types of cancer and are considered crucial. Tetravalent platinum (Pt(IV)) compounds have gained significant attention and have been extensively researched among these drugs. Traditionally, Pt(IV) compounds are reduced to divalent platinum (Pt(II)) after entering cells, causing DNA lesions and exhibiting their anti-tumor effect. However, the available evidence indicates that some Pt(IV) derivatives may differ from the traditional mechanism and exert their anti-tumor effect through their overall structure. This review primarily focuses on the existing literature regarding targeted Pt(II) and Pt(IV) compounds, with a specific emphasis on their in vivo mode of action and the properties of reduction release in multifunctional Pt(IV) compounds. This review provides a comprehensive summary of the design and synthesis strategies employed for Pt(II) derivatives that selectively target various enzymes (glucose receptor, folate, telomerase, etc.) or substances (mitochondria, oleic acid, etc.). Furthermore, it thoroughly examines and summarizes the rational design, anti-tumor mechanism of action, and reductive release capacity of novel multifunctional Pt(IV) compounds, such as those targeting p53-MDM2, COX-2, lipid metabolism, dual drugs, and drug delivery systems. Finally, this review aims to provide theoretical support for the rational design and development of new targeted Pt(IV) compounds.


Assuntos
Antineoplásicos , Neoplasias , Pró-Fármacos , Humanos , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Platina/química , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral
3.
ACS Nano ; 18(3): 2261-2278, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38207332

RESUMO

Sepsis, which is the most severe clinical manifestation of acute infection and has a mortality rate higher than that of cancer, represents a significant global public health burden. Persistent methicillin-resistant Staphylococcus aureus (MRSA) infection and further host immune paralysis are the leading causes of sepsis-associated death, but limited clinical interventions that target sepsis have failed to effectively restore immune homeostasis to enable complete eradication of MRSA. To restimulate anti-MRSA innate immunity, we developed CRV peptide-modified lipid nanoparticles (CRV/LNP-RNAs) for transient in situ programming of macrophages (MΦs). The CRV/LNP-RNAs enabled the delivery of MRSA-targeted chimeric antigen receptor (CAR) mRNA (SasA-CAR mRNA) and CASP11 (a key MRSA intracellular evasion target) siRNA to MΦs in situ, yielding CAR-MΦs with boosted bactericidal potency. Specifically, our results demonstrated that the engineered MΦs could efficiently phagocytose and digest MRSA intracellularly, preventing immune evasion by the "superbug" MRSA. Our findings highlight the potential of nanoparticle-enabled in vivo generation of CAR-MΦs as a therapeutic platform for multidrug-resistant (MDR) bacterial infections and should be confirmed in clinical trials.


Assuntos
Lipossomos , Staphylococcus aureus Resistente à Meticilina , Nanopartículas , Receptores de Antígenos Quiméricos , Sepse , Infecções Estafilocócicas , Animais , Camundongos , Receptores de Antígenos Quiméricos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , RNA Mensageiro , Antibacterianos/farmacologia , Macrófagos , Sepse/tratamento farmacológico , Lipídeos/farmacologia
4.
Sci Total Environ ; 916: 170316, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38278236

RESUMO

Aerosol particles in two size ranges, namely 0.18-1.4 µm (fine) and larger than 1.4 µm (coarse), were collected in the pre-dust, in-dust, and post-dust air during the passage of a slowly-moving dust event at a coastal site in southwestern Japan. We identified the composition and size of individual particles using a scanning electron microscope to investigate the variations during dust passage. The particles could be classified as mineral-seasalt mixtures, non-mixture minerals, sulfur-containing minerals, and seasalt particles, and the number fractions of these type particles in the two size ranges exhibited significant variation across the three periods. In the coarse size range, mixture particles accounted for 17.6 %, 26.8 %, and 37.8 % of the particles in the pre-dust, in-dust, and post-dust air, respectively. Non-mixture particles made up 36.8 %, 29.2 %, and 24.3 % in the same respective periods. In the in-dust air, the average relative ratio of sulfur content in sulfur-containing mineral particles in the coarse range was 5.5 %, whereas in the fine range, it was 17.2 %. The aging state of sea salt components, described by the Cl loss and reflecting the changes in particles due to chemical reactions, exhibited significant differences in the two size ranges. In the fine range, the aging of >90 % particles was predominantly influenced by sulfate formation in the in-dust air. In contrast, nitrate likely played a certain role in both the pre-dust and post-dust air. In the coarse range, the aging was independent of sulfate formation. These results indicate the close dependence of the aging of dust particles on their size and the notable variations of the aged states, underscoring the essentiality to treat dust particles properly according to time and space for a better understanding on their roles in the marine atmosphere.

5.
J Virol ; 98(1): e0135923, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38084959

RESUMO

Phage therapy has shown great promise for the treatment of multidrug-resistant bacterial infections. However, the lack of a thorough and organized understanding of phage-body interactions has limited its clinical application. Here, we administered different purified phages (Salmonella phage SE_SZW1, Acinetobacter phage AB_SZ6, and Pseudomonas phage PA_LZ7) intravenously to healthy animals (rats and monkeys) to evaluate the phage-induced host responses and phage pharmacokinetics with different intravenous (IV) doses in healthy animals. The plasma and the organs were sampled after different IV doses to determine the phage biodistribution, phage-induced cytokines, and antibodies. The potential side effects of phages on animals were assessed. A non-compartment model revealed that the plasma phage titer gradually decreased over time following a single dose. Repeated doses resulted in a 2-3 Log10 decline of the plasma phage titer at 5 min compared to the first dose, regardless of the type of phage administered in rats. Host innate immune responses were activated including splenic enlargement following repeated doses. Phage-specific neutralization antibodies in animals receiving phages were detected. Similar results were obtained from monkeys. In conclusion, the mammalian bodies were well-tolerant to the administered phages. The animal responses to the phages and the phage biodistribution profiles could have a significant impact on the efficacy of phage therapy.IMPORTANCEPhage therapy has demonstrated potential in addressing multidrug-resistant bacterial infections. However, an insufficient understanding of phage-host interactions has impeded its broader clinical application. In our study, specific phages were administered intravenously (IV) to both rats and monkeys to elucidate phage-host interactions and evaluate phage pharmacokinetics (PK). Results revealed that with successive IV administrations, there was a decrease in plasma phage concentrations. Concurrently, these administrations elicited both innate and adaptive immune responses in the subjects. Notably, the observed immune responses and PK profiles exhibited variation contingent upon the phage type and the mammalian host. Despite these variations, the tested mammals exhibited a favorable tolerance to the IV-administered phages. This underscores the significance of comprehending these interactions for the optimization of phage therapy outcomes.


Assuntos
Infecções Bacterianas , Bacteriófagos , Terapia por Fagos , Animais , Humanos , Ratos , Infecções Bacterianas/terapia , Bacteriófagos/fisiologia , Mamíferos , Fagos de Pseudomonas , Distribuição Tecidual , Farmacorresistência Bacteriana Múltipla
6.
Microbiol Spectr ; 12(1): e0188223, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38014983

RESUMO

IMPORTANCE: Phage therapy is gaining traction as an alternative to antibiotics due to the rise of multi-drug-resistant (MDR) bacteria. This study assessed the pharmacokinetics and safety of PA_LZ7, a phage targeting MDR Pseudomonas aeruginosa, in mice. After intravenous administration, the phage showed an exponential decay in plasma and its concentration dropped significantly within 24 h for all dosage groups. Although there was a temporary increase in certain plasma cytokines and spleen weight at higher dosages, no significant toxicity was observed. Therefore, PA_LZ7 shows potential as an effective and safe candidate for future phage therapy against MDR P. aeruginosa infections.


Assuntos
Bacteriófagos , Infecções por Pseudomonas , Fagos de Pseudomonas , Animais , Camundongos , Fagos de Pseudomonas/genética , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Infecções por Pseudomonas/terapia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa
7.
Adv Mater ; 36(13): e2311109, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38127403

RESUMO

Glioblastoma multiforme (GBM) is notoriously resistant to immunotherapy due to its intricate immunosuppressive tumor microenvironment (TME). Dysregulated cholesterol metabolism is implicated in the TME and promotes tumor progression. Here, it is found that cholesterol levels in GBM tissues are abnormally high, and glioma-supportive macrophages (GSMs), an essential "cholesterol factory", demonstrate aberrantly hyperactive cholesterol metabolism and efflux, providing cholesterol to fuel GBM growth and induce CD8+ T cells exhaustion. Bioinformatics analysis confirms that high 7-dehydrocholesterol reductase (DHCR7) level in GBM tissues associates with increased cholesterol biosynthesis, suppressed tumoricidal immune response, and poor patient survival, and DHCR7 expression level is significantly elevated in GSMs. Therefore, an intracavitary sprayable nanoregulator (NR)-encased hydrogel system to modulate cholesterol metabolism of GSMs is reported. The degradable NR-mediated ablation of DHCR7 in GSMs effectively suppresses cholesterol supply and activates T-cell immunity. Moreover, the combination of Toll-like receptor 7/8 (TLR7/8) agonists significantly promotes GSM polarization to antitumor phenotypes and ameliorates the TME. Treatment with the hybrid system exhibits superior antitumor effects in the orthotopic GBM model and postsurgical recurrence model. Altogether, the findings unravel the role of GSMs DHCR7/cholesterol signaling in the regulation of TME, presenting a potential treatment strategy that warrants further clinical trials.


Assuntos
Neoplasias Encefálicas , Dissacarídeos , Glioblastoma , Glioma , Glucuronatos , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Linfócitos T CD8-Positivos/metabolismo , Hidrogéis/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Glioma/patologia , Macrófagos/metabolismo , Imunoterapia , Colesterol , Microambiente Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo
8.
Biomed Mater ; 19(1)2023 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-37972551

RESUMO

A multifunctional hydrogel dressing with hemostatic, antibacterial, and reactive oxygen species (ROS)-removing properties is highly desirable for the clinical treatment of open wounds. Although many wound dressings have been prepared, the modification of polymers is often involved in the preparation process, and the uncertainty of biological safety and stability of modified polymers hinders the clinical application of products. In this study, inspired by the composition and crosslinking pattern of extracellular matrix (ECM), a deeply ECM-mimicking multifunctional hydrogel dressing is created. Tannic acid (TA) and poly-ϵ-lysine (EPL) are added into a gelatin/hyaluronic acid (Gel/HA) matrix, and a stable hydrogel is formed due to the formation of the triple helix bundles of gelatin and hydrogen bonds between polymers. The introduction of TA and EPL endows the ECM-mimicking hydrogel with stable rheological properties, as well as antibacterial and hemostatic functions. The as-produced hydrogels have suitable swelling ratio, enzyme degradability, and good biocompatibility. In addition, it also shows a significant ability to eliminate ROS, which is confirmed by the elimination of 2,2-diphenyl-1-picrylhydrazyl free radical. Full-thickness skin wound repair experiment and histological analysis of the healing site in mice demonstrate that the developed ECM-mimicking Gel/HA hydrogels have a prominent effect on ECM formation and promotion of wound closure. Taken together, these findings suggest that the multifunctional hydrogels deeply mimicking the ECM are promising candidates for the clinical treatment of open wounds.


Assuntos
Gelatina , Hemostáticos , Animais , Camundongos , Hidrogéis , Ácido Hialurônico , Espécies Reativas de Oxigênio , Antibacterianos , Matriz Extracelular , Lisina , Polímeros , Cicatrização
9.
J Struct Biol ; 215(3): 107996, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37419228

RESUMO

The evolving SARS-CoV-2 Omicron strain has repeatedly caused widespread disease epidemics, and effective antibody drugs continue to be in short supply. Here, we identified a batch of nanobodies with high affinity for receptor binding domain (RBD) of SARS-CoV-2 spike protein, separated them into three classes using high performance liquid chromatography (HPLC), and then resolved the crystal structure of the ternary complexes of two non-competing nanobodies (NB1C6 and NB1B5) with RBD using X-ray crystallography. The structures showed that NB1B5 and NB1C6 bind to the left and right flank of the RBD, respectively, and that the binding epitopes are highly conserved cryptic sites in all SARS-CoV-2 mutant strains, as well as that NB1B5 can effectively block the ACE2. These two nanobodies were covalently linked into multivalent and bi-paratopic formats, and have a high affinity and neutralization potency for omicron, potentially inhibiting viral escape. The binding sites of these two nanobodies are relatively conserved, which help guide the structural design of antibodies targeting future variants of SARS-CoV-2 to combat COVID-19 epidemics and pandemics.


Assuntos
COVID-19 , Anticorpos de Domínio Único , Humanos , SARS-CoV-2/genética , Anticorpos , Epitopos/genética , Anticorpos Neutralizantes
10.
Sci Total Environ ; 881: 163476, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37075995

RESUMO

Salt deterioration has been found to be a major threat to wall paintings at culture heritage sites in arid areas along the Silk Road. However, the routes of water migration that cause the efflorescence have not been identified, and consequently, effective preservation measures have not been developed. Our microanalysis, by interrogating 93,727 individual particles collected in a Mogao cave in Dunhuang, China, revealed that capillary rise of water in the earthen plasters drives the deterioration of wall paintings. The vertical distribution of chloride and sulfate particles in the salt efflorescence and their morphologies implied a migration of salts through capillary rise and subsequent crystal growth under environmental conditions exerts sufficient pressure to cause surface decay and loss. These results indicate that blocking the water capillary rise under the porous structures is likely the most effective route to prevent rapid deterioration of the ancient wall paintings. These salt transport and deterioration mechanisms in an arid environment, suggests that a wide range of management strategies and protective measures could be developed to effectively preserve heritage sites in arid regions, especially along the Silk Road.

11.
Sci Total Environ ; 875: 162655, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36894079

RESUMO

Accurate assessments of soluble phosphorus (P) in aerosol particles are essential to understand the atmospheric nutrients supply to the marine ecosystem. We quantified total P (TP) and dissolved P (DP) in the aerosol particles collected in the sea areas near China in a cruise mission from May 1 to June 11, 2016. The overall concentrations of TP and DP were 3.5-99.9 ng m-3 and 2.5-27.0 ng m-3, respectively. When the air originating from the desert areas, TP and DP were 28.7-99.9 ng m-3 and 10.8-27.0 ng m-3, respectively, and P solubility was 24.1-54.6 %. When the air influenced mainly by anthropogenic emissions from eastern China, TP and DP were 11.7-12.3 ng m-3 and 5.7-6.3 ng m-3, respectively, and P solubility was 46.0-53.7 %. More than half of the TP and more than 70 % of the DP were from pyrogenic particles, with a considerable DP converted via aerosol acidification after the particles met humid marine air. On average, aerosol acidification promoted the fractional solubility of dissolved inorganic P (DIP) to TP from 22 % to 43 %. When the air originating from the marine areas, TP and DP were 3.5-22.0 ng m-3 and 2.5-8.4 ng m-3, respectively, and P solubility was 34.6-93.6 %. About one-third of the DP was from biological emissions in organic forms (DOP), leading to higher solubility than in the particles from continental sources. These results reveal the dominance of inorganic P in TP and DP from the desert and anthropogenic mineral dust and the significant contribution of organic P from marine sources. The results also indicate the necessity to treat aerosol P carefully according to different sources of the aerosol particles and atmospheric processes the particles experience in assessing aerosol P input to seawater.

12.
Heliyon ; 9(3): e14026, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36915542

RESUMO

GW117, a novel derivate compound of agomelatine that acts as both a 5-HT2C receptor antagonist and a MT1/MT2 receptor agonist, likely underlines the potent antidepressant action with less hepatotoxicity than agomelatine. We evaluated the acute toxicity of GW117, and the genotoxicity of GW117 using bacterial reverse mutation test, mammalian chromosomal aberration test in Chinese hamster lung cells (CHL) and mouse bone marrow micronucleus test. The acute toxicity test results showed that maximum tolerated dose (MTD) of GW117 was 2000 mg/kg, under which mean Cmax and AUC0→t was 10,782 ng/mL and 81,046 ng/mL × h, respectively. The result of bacterial reverse mutation test showed that the number of bacterial colonies in each dose group of GW117 did not increase significantly compared with that in the solvent control group with or without S9 metabolic activation system. In vitro chromosome aberration test of CHL cells, the chromosome aberration rate of each dose group of GW117 did not increase with or without S9 metabolic activation system. In mouse micronucleus test, the highest dose was 2000 mg/kg, the micronucleus rate did not increase significantly. Under the conditions of this study, the MTD of a single GW117 administration was 2000 mg/kg, there was no genotoxicity effect of GW117.

13.
J Biomed Mater Res B Appl Biomater ; 111(7): 1407-1418, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36930047

RESUMO

Poly-γ-glutamic acid (PGA) is a naturally degradable hydrophilic linear microbial polymer with moisturizing, immunogenic, cross-linking, and hydrogel water absorption properties similar to hyaluronic acid, a biomaterial that is commonly used as a dermal filler. To explore the development feasibility of cross-linked PGA as a novel dermal filler, we studied the local skin response to PGA fillers and the effect of various cross-linking preparations on the average longevity of dermal injection. Injection site inflammation and the formation of collagen and elastin were also determined. PGA hydrogel particles prepared using 28% PGA and 10% 1,4-butanediol diglycidyl ether showed optimal filler properties, resistance to moist heat sterilization, and an average filling longevity of 94.7 ± 61.6 days in the dermis of rabbit ears. Local redness and swelling due to filler injection recovered within 14.2 ± 3.6 days. Local tissue necrosis or systemic allergic reactions were not observed, and local collagen formation was promoted. Preliminary results suggested that dermal injection of cross-linked PGA particles appeared safe and effective, suggesting that cross-linked PGA particles could be developed as a new hydrogel dermal filler.


Assuntos
Preenchedores Dérmicos , Hidrogéis , Animais , Coelhos , Materiais Biocompatíveis , Butileno Glicóis , Excipientes , Ácido Glutâmico , Ácido Hialurônico , Hidrogéis/farmacologia
14.
Molecules ; 28(4)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36838727

RESUMO

Sclareolide is a sesquiterpene lactone isolated from various plant sources in tons every year and is commercially used as a flavor ingredient in the cosmetic and food industries. Antitumor and antiviral activities of sclareolide have been previously reported. However, biological studies of sclareolide synthetic analogous are few. In view of these, we developed a robust synthetic method that allows the assembly of 36 novel sclareolide-indole conjugates and their derivatives. The synthetic method was based on TiCl4-promoted nucleophilic substitution of sclareolide-derived hemiacetal 4, while electron-rich aryles including indoles, polyphenol ethers, and pyrazolo [1,5-a]pyridine were good substrates. The stereochemistry of the final products was confirmed by single-crystal X-ray diffraction analysis, while the antiproliferative activities of selected final products were tested in K562 and MV4-11 cancer cell lines. Cytometric flow analysis shows that lead compounds 8k- and 10-induced robust apoptosis in MV4-11 cancer cells, while they exhibited weak impact on cell cycle progression. Taken together, our study suggests that sclareolide could be a good template and substrate for the synthesis of novel antiproliferative compounds.


Assuntos
Antineoplásicos , Diterpenos , Antineoplásicos/farmacologia , Indóis/química , Diterpenos/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Relação Estrutura-Atividade , Linhagem Celular Tumoral
15.
Sci Total Environ ; 865: 161238, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36586682

RESUMO

Size-differentiated concentration of bacterial aerosols is essential for investigating their dissemination via the atmosphere. In this study, the number size distribution of bacterial aerosols was measured at a coastal site in southwestern Japan (32.324°N, 129.993°E) using a size-segregated eight-stage (>11, 7.0-11, 4.7-7.0, 3.3-4.7, 2.1-3.3, 1.1-2.1, 0.65-1.1, and 0.43-0.65µm) sampler. The results showed that the distribution differed according to the source areas: terrestrial air, oceanic air, or a combination of the two. The distribution in the long-distance transported terrestrial air from the Asian continent was monomodal, with a peak of 3.3-4.7 µm. The distribution in local land breeze air was bimodal, with the peaks at 0.43-1.1 and 3.3-4.7 µm. A similar bimodal distribution was encountered when the local island air and long-distance transported terrestrial air mixed. In contrast, the size distribution did not show clear peaks in the air from either nearby or remote marine areas. According to the air mass backward trajectories, the further the distance the air moved in the 72 h before arriving at the site, the lower the concentration of total bacterial aerosols. The estimation of dry deposition fluxes of bacterial cells showed that the deposition was dominated by cells larger than 1.1 µm with a relative contribution from 70.5 % to 93.7 %, except for the local land breeze cases, where the contributions in the size ranges larger and smaller than 1.1 µm were similar. These results show the distinctive number size distributions and removal processes of bacterial aerosols in different types of air. In addition, they indicate that size-dependent characteristics of airborne bacteria should be considered when studying their activities and roles in the atmospheric environment.


Assuntos
Poluentes Atmosféricos , Aerossóis/análise , Poluentes Atmosféricos/análise , Atmosfera , Bactérias , Monitoramento Ambiental/métodos , Japão , Tamanho da Partícula , Material Particulado/análise
16.
Sci Total Environ ; 858(Pt 2): 159948, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336053

RESUMO

Source apportionments of urban aerosols identified with positive matrix factorization (PMF) are sensitive to input variables. So far, total elements were frequently included as effective factors in PMF-based source apportionment. We investigated the advances to involve soluble parts of elements in the source apportionment with four data sets of PM2.5 composition observed at a coastal city (Qingdao) in northern China: water-soluble ions plus organic and elemental carbon (IC set), the IC set plus total elements (ICTE set), the IC set plus soluble elements (ICSE set), and the IC set plus both total elements and soluble elements (ICAE set). The apportionments of six sources, including secondary sulfate, secondary nitrate, secondary oxalate, sea salt, biomass burning and dust, were identified with the IC set. In comparison, pollutants from vehicle + coal combustion, ship emissions, waste incineration and industrial activities were also identified with the ICTE, ICSE, or ICAE sets. We found that the PMF solutions of the ICAE set could distinguish aged and fresh dust, and identify fly ash and aged pollutants from industrial sources. The profiles and corresponding time series of vehicle + coal combustion, secondary aerosols, ship emissions, sea salt, and biomass burning emissions identified with the four data sets were very similar, while discrepancies were encountered for waste incineration, dust, and industrial sources. These results indicate the benefits and potentials with total and soluble elements involved in PMF-based source apportionments.


Assuntos
Poluentes Atmosféricos , Material Particulado , Material Particulado/análise , Poluentes Atmosféricos/análise , Emissões de Veículos/análise , Monitoramento Ambiental/métodos , Poeira/análise , Aerossóis/análise , Carvão Mineral/análise , Nitratos/análise , China , Estações do Ano
17.
J Appl Toxicol ; 43(4): 577-588, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36268681

RESUMO

GW117 is new melatonergic antidepressant being developed to show better antidepressant action than agomelatine. The purpose of this study was to evaluate the toxicity and to determine potential target organs after oral (gavage) administration of the test article GW117 for 28 days and to assess the reversibility after a 4-week recovery phase in beagle dogs. Toxicokinetics was also evaluated. Four groups were designed in this study, including the vehicle control group and the GW117 50, 150 and 500 mg/kg/day groups, with 5 dogs/sex/group. Body weight, hematology, clinical chemistry, gross necropsy, organ weight, histopathology, and other indicators were examined. Results showed that animals dosed at ≥150 mg/kg/day showed gastrointestinal reactions (watery feces and dark green/red brown feces), with a dose-response relationship in the incidence and severity grade. Female dogs at 500 mg/kg/day had an increase in organ weight and ratios of the liver at the end of the dosing phase. Histopathology examination showed that some animals at 500 mg/kg/day, especially female animals, had minimal centrilobular hepatocyte hypertrophy in the liver, which reversed after 28-day recovery. With the exception of the above, no GW117-related abnormality was noted. Meanwhile, there were no sexual differences in drug exposure and accumulation after the first and last dosing. The no observed adverse effect dose level (NOAEL) was 150 mg/kg/day, under which mean Cmax and AUC0 → t were 583.5 and 2767.0 ng/ml*h for females and 663.2 and 4046.3 ng/ml*h for males on Day 28.


Assuntos
Fígado , Masculino , Cães , Animais , Feminino , Toxicocinética , Nível de Efeito Adverso não Observado
18.
Sci Total Environ ; 864: 161040, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36572311

RESUMO

The dissemination of bioaerosols in the westerly wind from the Asian continent to the northwestern Pacific constantly links the land and marine ecosystems. Several observation campaigns targeting bioaerosols were conducted in the coastal city Qingdao of China (QD), at a coast site of Kumamoto in southwestern Japan (KM), and in the northwestern Pacific (NP) between 2014 and 2016. We compared the concentration of bioaerosols in the range of 1.1-7.0 µm obtained in those campaigns to investigate their variation in the westerly wind. The substantial influence of westerlies on bioaerosol concentration was confirmed in the three areas. In the case of non-dust air, the arrival of the continental air led to a 29 % decrease of bioaerosols at KM while a 57 % increase at NP, indicating that the concentration in non-dust air was lower than the local level in the island air while higher than that in the remote marine air. In case of dust occurrence, bioaerosols in the air decreased with the distance from the Asian continent at KM and NP consecutively, and the arrival of the air caused a 2-fold increase at KM and a 1.7-fold increase at NP. The relative concentration increase rate of bioaerosols (IRRC), defined as the ratio of the increment of bioaerosols caused by long-distance transported air to the local level in each area, decreased rapidly after the air left the continent in the dust cases, which is similar to the decrease of the dry deposition flux of dust reported in the literature. This result indicates that the reduction of bioaerosols in the dusty air was likely dominated by the removal of bioaerosols attached to dust particles.


Assuntos
Poluentes Atmosféricos , Humanos , Aerossóis/análise , Microbiologia do Ar , Poluentes Atmosféricos/análise , Poeira/análise , Ecossistema , Monitoramento Ambiental , Vento
19.
Front Immunol ; 13: 961805, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304470

RESUMO

Immune checkpoint therapy via PD-1 antibodies has shown exciting clinical value and robust therapeutic potential in clinical practice. It can significantly improve progression-free survival and overall survival. Following surgery, radiotherapy, chemotherapy, and targeted therapy, cancer treatment has now entered the age of immunotherapy. Although cancer immunotherapy has shown remarkable efficacy, it also suffers from limitations such as irAEs, cytokine storm, low response rate, etc. In this review, we discuss the basic classification, research progress, and limitations of cancer immunotherapy. Besides, by combining cancer immunotherapy resistance mechanism with analysis of combination therapy, we give our insights into the development of new anticancer immunotherapy strategies.


Assuntos
Imunoterapia , Neoplasias , Terapia Combinada , Fatores Imunológicos , Neoplasias/terapia
20.
Environ Sci Technol ; 56(22): 16453-16461, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36316194

RESUMO

Aerosol iron (Fe) solubility is a key factor for the assessment of atmospheric nutrients input to the ocean but poorly specified in models because the mechanism of determining the solubility is unclear. We develop a deep learning model to project the solubility based on the data that we observed in a coastal city of China. The model has five variables: the size range of particles, relative humidity, and the ratios of sulfate, nitrate and oxalate to total Fe (TFe) contents in aerosol particles. Results show excellent statistical agreements with the solubility in the literature over most worldwide seas and margin areas with the Pearson correlation coefficients (r) as large as 0.73-0.97. The exception is the Atlantic Ocean, where good agreement is obtained with the model trained using local data (r: 0.34-0.66). The model further uncovers that the ratio of oxalate/TFe is the most important variable influencing the solubility. These results indicate the feasibility of treating the solubility as a function of the six factors in deep learning models with careful training and validation. Our model and projected solubility provide innovative options for better quantification of air-to-sea input of aerosol soluble Fe in observational and model studies in the global marine atmosphere.


Assuntos
Atmosfera , Ferro , Aerossóis , Aprendizado de Máquina , Oxalatos , Solubilidade
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