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1.
Plant Dis ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506908

RESUMO

Lotus (Nelumbo nucifera Gaertn.) is a widely cultivated plant in China, and the fruit lotus variety has a high economic value attributed to the exquisite flavor of its fresh seeds. During the summer of 2023, an unidentified blight was observed affecting lotus seedpods in Jiande City, Zhejiang province, with approximately 65% of seedpods impacted in a 130-hectare area. The initial symptoms included dark purple spots on the lotus seedpod surface, which gradually expanded over time. After 5 to 7 days, the entire seedpod turned black, withering, and rendering the lotus seeds inedible. To identify the causal agent, tissues from symptomatic seedpods were excised and disinfected in 75% ethanol for 60 s, and washed twice in sterile distilled water. The disinfected symptomatic tissues (5 × 5 mm) were plated on potato dextrose agar (PDA), incubated at 25 ℃, transferred hyphal tips to obtain pure isolates after 3 days. Fungal colonies exhibiting Botryosphaeriaceae morphology were isolated from 33% of the samples (n = 15). Pure cultures were grown on PDA for both morphological and molecular identification. The colonies displayed a white aerial mycelium, turning olivaceous grey after 7 days. Pycnidia were produced within 3 weeks on PDA with added sterilized healthy lotus seedpod pieces on the surface. Conidia were hyaline, unicellular, ellipsoidal, 12.65 to 20.72 × 3.92 to 9.38 µm in size (mean 16.67 × 6.24 µm, n = 100). To determine the fungal species, genomic DNA was extracted from one representative isolate (ZJUP1112-1), to amplify four gene loci through polymerase chain reactions (PCR): rDNA internal transcribed spacer (ITS) with primers ITS1/ITS4, rDNA large subunit (LSU) with LR0R/LR5, the translation elongation factor 1-alpha gene (tef1) with EF1-728F/EF1-986R, and ß-tubulin gene (tub2) with Bt2a/Bt2b. The PCR products were Sanger sequenced in Zhejiang Shangya biotechnology co., LTD, and the resulting sequences were assembled and deposited in GenBank (ITS: OR740546; LSU: OR740547; tef1: OR776996; tub2: OR776997). BLAST searches indicated the highest nucleotide sequence identity with the reference strains of Neofusicoccum parvum CMW 9081 (ITS: 98.8%, AY236943; LSU: 100%, AY928045; tef1: 99.6%, AY236888; tub2: 99.3%, AY236917). Multi-locus phylogenetic analyses revealed that isolate ZJUP1112-1 formed a highly supported clade with N. parvum. Pathogenicity tests were performed on healthy lotus seedpods using mycelial plugs (5 mm diameter) from actively growing colonies of ZJUP1112-1 that were placed onto the front and side of the seedpods (6 each). Controls received PDA plugs. Treated seedpods were wrapped with parafilm and incubated at 25 ℃ and the experiment was repeated three times. After 5 days, dark purple lesions were observed on the inoculated seedpods, whereas controls remained symptomless. The same isolate was recovered from the margin of resulting lesions and confirmed by morphology, thus fulfilling Koch's postulates. N. parvum is a polyphagous pathogen causing blights and fruit rot on multiple economically important fruit crops, such as cacao (Puig et al. 2019), walnut (Chen et al. 2019), pistachio (Lopez-Moral et al. 2020), chestnut (Seddaiu et al. 2021), blueberry (Spetik et al. 2023) and mango (Polizzi et al. 2022), among others. To the best of our knowledge, this is the first report of N. parvum causing seedpod blight on lotus seedpods in China, which contributes to a better understanding of the pathogens affecting this plant species in China.

2.
Plant Dis ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386298

RESUMO

In June 2023, a sudden outbreak root rot and vine decline symptoms was observed during a watermelon (Citrullus lanatus T.) variety demonstration trial located in Taizhou City, Zhejiang Province, China, with an incidence rate ranging from 75% to 100% and an affected area of nearly 2,000 square meters. The disease initially appeared with a rapid and alarming invasion of root rot and vine decline symptoms within watermelon plants. Affected plants exhibited rapid deterioration, showing symptoms of wilting, yellowing and eventual demise, predominantly during the pre-harvest stage. Notably, numerous black, spherical, erumpent perithecia were clearly visible on the watermelon's root epidermis, a characteristic trait of the disease. Symptomatic plant samples were rigorously disinfected with 75% ethanol, and plated on potato dextrose agar medium for incubation at 25°C, successfully isolate two potential strains. These isolates were inoculated in oatmeal agar and incubated in a 25℃ light incubator. After 30 days, mature perithecia, the same as those found on the watermelon's root epidermis, reached a diameter of 500 µm. Each perithecium contained several pear-shaped asci, 56 to 108.5 µm in length and 30.5 to 46.4 µm in width, typically holding 1, rarely 2 ascospores. These characteristics align precisely with the typical strains of Monosporascus cannonballus Pollack and Uecker (1974). Additionally, sequencing the internal transcribed spacer region of ribosomal DNA (ITS) gene (White et al., 1990), large subunit ribosomal RNA (LSU) gene (Rehner and Samuels 1995), and beta-tubulin (TUB) gene (Glass and Donaldson, 1995) were performed. BLAST analysis indicated the highest nucleotide sequence identity with M. cannonballus CBS 586.93 reference sequence (ITS: 100%, JQ771930; TUB: 98.99%, JQ907292). Representative sequences of isolate ZJUP0990-2 from these regions were deposited in GenBank (Accession No.: OR357656 for ITS; OR474500 for LSU; OR365762 for TUB). A multigene phylogenomic analysis (ITS-LSU-TUB) was undertaken to ascertain the exact phylogenetic position of M. cannonballus within the genus Monosporascus. The amalgamation of both morphological and molecular insights consistently reaffirmed the accurate classification of the causative agent as M. cannonballus. To validate the pathogenicity of M. cannonballus, a controlled greenhouse experiment was conducted using watermelon (cv. Nabite) as the subject. Mycelium fragments, harvested from the edge of the colony ZJUP0990-2, were inoculated into oat liquid medium and cultivated under dark conditions at a consistent temperature of 30°C for 7 days. After 20 days, the inoculated plants exhibited root rot and wilting, mirroring the symptoms observed during the field outbreak. In contrast, the control plants did not exhibit any signs of disease. M. cannonballus was successfully re-isolated from the symptomatic roots of the inoculated plants, satisfying Koch's postulates. This experiment was repeated three times. This pathogenic fungus has previously been documented as a menace to melons in various regions including Mexico (Chew-Madinaveitia et al., 2012) and Brazil (Sales et al., 2004), as well as watermelons in Brazil (Sales et al., 2010), northern Mexico (Gaytan-Mascorro et al., 2012), and Saudi Arabia (Karlatti et al., 1997). To our knowledge, this is the first reported presence of M. cannonballus on watermelons in China. This new disease poses a serious threat to watermelon production, potentially leading to severe economic losses and impacting food security.

3.
Front Cell Infect Microbiol ; 13: 1282902, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029240

RESUMO

Objectives: This study summarizes the epidemiological characteristics, species distribution, and drug sensitivity of clinical nontuberculous mycobacteria (NTM) isolates at the Public Health Clinical Center of Chengdu, China, from January 2017 to December 2022. Methods: We retrospectively analyzed data from patients with clinically isolated NTM strains. Chi-square analysis assessed the rate of Mycobacterium strain isolation over 6 years. Results: The number of samples tested for Mycobacterium tuberculosis (MTB) and/or NTM increased each year, while MTB detection decreased and NTM detection rose significantly each year (P=0.03). The average age of NTM patients was 51 ± 17.53 years, with a 14.1% HIV infection rate. The predominant isolates were Mycobacterium avium-intracellulare (MAC) and M. chelonae/M. abscessus, with 96.4% of cases being of Han ethnicity. Amikacin, moxifloxacin, and clarithromycin were effective against M. avium and M. intracellulare; linezolid, amikacin, and cefoxitin were effective against M. chelonae/M. abscessus. Over 90% of NTM cases originated from the respiratory tract. Conclusion: The NTM isolation rate in Southwest China has risen in recent years, primarily among elderly patients with a high HIV co-infection rate. The main NTM isolates were MAC and M. chelonae/M. abscessus. Amikacin, moxifloxacin, clarithromycin, and linezolid exhibited strong antibacterial activity against SGM, while amikacin and linezolid displayed relatively better antibacterial activity against RGM. The prevalence of NTM infection may be positively associated with regional economic development and health conditions.


Assuntos
Infecções por HIV , Infecções por Mycobacterium não Tuberculosas , Tuberculose , Humanos , Idoso , Adulto , Pessoa de Meia-Idade , Micobactérias não Tuberculosas , Claritromicina/farmacologia , Amicacina/farmacologia , Linezolida/farmacologia , Linezolida/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Moxifloxacina/farmacologia , Estudos Retrospectivos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Tuberculose/epidemiologia , China/epidemiologia , Testes de Sensibilidade Microbiana
4.
Plants (Basel) ; 12(20)2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37896099

RESUMO

Tomato pith necrosis (TPN) is a highly destructive disease caused by species of the Pseudomonas genus and other bacteria, resulting in a significant reduction in tomato yield. Members of the genus Bacillus are beneficial microorganisms extensively studied in the rhizosphere. However, in most cases, the potential of Bacillus members in controlling TPN and their impact on the rhizosphere microbial composition remain rarely studied. In this study, Bacillus velezensis ZN-S10 significantly inhibited the growth of Pseudomonas viridiflava ZJUP0398-2, and ZN-S10 controlled TPN with control efficacies of 60.31%. P. viridiflava ZJUP0398-2 significantly altered the richness and diversity of the tomato rhizobacterial community, but pre-inoculation with ZN-S10 mitigated these changes. The correlation analysis revealed that ZN-S10 maybe inhibits the growth of nitrogen-fixing bacteria and recruits beneficial bacterial communities associated with disease resistance, thereby suppressing the occurrence of diseases. In summary, the comparative analysis of the rhizosphere microbiome was conducted to explore the impact of ZN-S10 on the composition of rhizosphere microorganisms in the presence of pathogenic bacteria, aiming to provide insights for further research and the development of scientific and eco-friendly control strategies for this disease.

5.
Huan Jing Ke Xue ; 44(9): 5242-5252, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699842

RESUMO

This study explores the pollution characteristics, risks, and sources of heavy metals in small-scale areas. Rongcheng District, Jieyang City, Guangdong Province was considered as the study area and enrichment factor (EF), pollution load index (PLI), potential ecological risk index (RI), and US EPA health risk assessment model were used to evaluate its environmental risk. Moreover, the source apportionment of heavy metals was analyzed through correlation analysis, the characteristic of spatial distribution, and a PMF model. The results showed that the mean concentrations of ω(Cr), ω(Hg), ω(As), ω(Pb), ω(Ni), ω(Cd), ω(Cu), and ω(Zn) were 54.87, 0.25, 8.35, 56.00, 15.38, 0.35, 30.56, and 124.23 mg·kg-1, respectively. The mean concentrations of all elements exceeded the local soil background value. In terms of EF level, Cr, As, Pb, and Ni showed negligible accumulation; Zn and Cu showed minor accumulation; and Hg and Cd showed moderate accumulation. The mean value of the pollution load index was 2.37, with a severe pollution level, and the eight elements were in different pollution levels. In total, the study region suffered severe ecological risk, Hg and Cd presented strong ecological risk, and other elements presented slight ecological risk. The non-carcinogenic risks under the three exposure paths were within the acceptable level. The carcinogenic risks (CR) of adults and children were 9.81E-05 and 5.59E-04, respectively, and Cr and As were the main contributors of CR. The results showed that the four sources of heavy metals were transportation sources (37.02%), parent material sources (18.53%), atmospheric deposition sources (26.49%), and industrial sources (17.96%).


Assuntos
Mercúrio , Metais Pesados , Adulto , Criança , Humanos , Cádmio , Chumbo , Carcinógenos , Medição de Risco , Solo
6.
J Acquir Immune Defic Syndr ; 91(S1): S35-S41, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36094513

RESUMO

BACKGROUND: Dolutegravir (DTG) may inhibit organic cation transporter-2 in renal tubules and elevate serum creatinine levels without true renal function deterioration. There are scarce data on the glomerular filtration rate (GFR) equations in Chinese HIV patients with DTG/TDF/3 TC. This retrospective study was to evaluate the changes in creatinine- and cystatin C-based estimated GFR values among Chinese adult HIV patients with initial highly active antiretroviral therapy (HAART) with DTG/TDF/3 TC for 48 weeks. SETTINGS: Retrospective analysis of Chinese adult HIV patients who received initial HAART with DTG/TDF/3 TC between January 2016 and May 2021. METHODS: We compared the changes in creatinine-based and cystatin C-based estimated GFR before and 48 weeks after HAART to determine the optimal tool for renal function estimation. RESULTS: Ninety-five patients [91.58% men; median age, 34 years (interquartile range, 29-44 years)] were enrolled. The median baseline CD4+ cell count was 185 cells/µL [interquartile range, 53-303 cells/µL] and the median baseline viral load was 148,000 copies/mL [interquartile range, 26,800-596,000 copies/mL]. The estimated GFR at 4, 12, and 24 weeks was significantly different than at baseline (P < 0.05) using all 4 equations. Only the GFR estimated using the CKD-EPIcreat and CKD-EPIcys equations was significantly different at 48 weeks of treatment (P < 0.05). The modification of diet in renal disease-based decline of GFR incidence at 4, 12, 24, and 48 weeks of treatment (21.5%, 24.21%, 33.68% and 38.95%, respectively) was higher than that calculated using the other 3 GFR equations. CONCLUSIONS: The modification of diet in renal disease equation may not be optimal for Chinese HIV-1-infected adults receiving DTG + TDF + 3 TC as the initial antiviral therapy. Clinicians must carefully choose the GFR equation for patients with HIV/hepatitis B virus coinfection.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Insuficiência Renal Crônica , Adulto , Creatinina , Cistatina C , Feminino , Taxa de Filtração Glomerular , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis , Humanos , Lamivudina/uso terapêutico , Masculino , Oxazinas , Piperazinas , Piridonas , Estudos Retrospectivos , Tenofovir/uso terapêutico
7.
Nat Commun ; 13(1): 3621, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35750872

RESUMO

Photo-controlled living polymerization has received great attention in recent years. However, despite the great success therein, the report on photo-controlled living cationic polymerization has been greatly limited. We demonstrate here a novel decolorable, metal-free and visible light-controlled living cationic polymerization system by using tris(2,4-dimethoxyphenyl)methylium tetrafluoroborate as the photocatalyst and phosphate as the chain transfer agent (CTA) for polymerization of 4-methoxystyrene. This polymerization reaction under green LED light irradiation shows clear living characteristics including predictable molar mass, low molar-mass dispersity (D = 1.25), and sequential polymerization capability. In addition, the photocatalytic system exits excellent "on-off" photo switchability and shows the longest "off period" of 36 h up to now for photo-controlled cationic polymerization. Furthermore, the residual photo-catalyst is easily deactivated and decolored with addition of a base after the polymerization. The present study has extended the photo-controlled living cationic polymerization systems with new organic photocatalysts, phosphate CTA and polymerizable monomer as well as the new properties of excellent photostability and in-situ decolored capacity.


Assuntos
Luz , Fosfatos , Catálise , Polimerização
9.
PeerJ ; 9: e11615, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178473

RESUMO

BACKGROUND: Cyclocarya paliurus (Batal.) Iljinskaja is a common endemic tree species and used as a Chinese medicine. The main active components in the leaves of this plant are polysaccharides. However, the temporal patterns of gene expression underlying the synthesis of polysaccharides in C. paliurus at different leaf developmental stages and its relationship with the polysaccharide content and antioxidant activities has not been reported to date. METHODS: RNA-seq was used to investigate the biosynthesis pathway of polysaccharides at the four developmental stages of C. paliurus leaves. The content and the antioxidant activities of polysaccharides were measured with typical biochemical methods and the identified correlations were statistically evaluated. RESULTS: Sixty-nine differentially expressed genes were found in the leaves during different developmental stages of C. paliurus. These are associated with glycosyltransferases and belong to 18 families. During different developmental stages of C. paliurus, the polysaccharide content first increased and then decreased, and the UDP-glucose 4-epimerase gene was found to be significantly positively correlated with the polysaccharide content. The clearance rates of DPPH radicals, superoxide anion radicals, hydroxyl radicals, and the reducing power of polysaccharides in the leaves of C. paliurus at different developmental stages showed a dose-dependent relationship with the concentration of polysaccharides. CONCLUSIONS: The smallest fully expanded leaves are suitable for high-quality tea, and leaves with sizes below the largest fully expanded leaves are suitable for industrial production of polysaccharides.

10.
ACS Omega ; 6(13): 9028-9038, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33842773

RESUMO

Flavonoids are a class of commonly occurring natural compounds in the plant kingdom with various biological activities. This study compares the content of flavonoids in Cyclocarya paliurus at different developmental stages to better inform the selection of the optimal picking period. Thus, we analyzed the transcriptome and metabolome of C. paliurus at different developmental stages. The transcriptome analysis revealed 44 genes involved in the biosynthesis of flavonoids in C. paliurus, with 10 differentially expressed genes across the four different developmental stages. The metabolites were separated and identified by a combination of chromatography and mass spectrometry, followed by multi-reaction monitoring mode analysis of triple quadrupole mass spectrometry for complete metabolite quantification. In the flavonoid synthesis pathway, a total of 137 differential flavonoids were detected. The joint transcriptome and metabolome analysis showed that the expression trends in differential metabolites and genes were significantly related. Four MYB transcription factors and two bHLH transcription factors that are closely related to flavonoid biosynthesis were identified. The regulation network of flavonoid biosynthesis in C. paliurus was thus established, providing guidance for follow-up research.

12.
Front Med (Lausanne) ; 8: 736109, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071254

RESUMO

Background: Some patients with comorbidities and rapid disease progression have a poor prognosis. Aim: We aimed to investigate the characteristics of comorbidities and their relationship with disease progression and outcomes of COVID-19 patients. Methods: A total of 718 COVID-19 patients were divided into five clinical type groups and eight age-interval groups. The characteristics of comorbidities were compared between the different clinical type groups and between the different age-interval groups, and their relationships with disease progression and outcomes of COVID-19 patients were assessed. Results: Approximately 91.23% (655/718) of COVID-19 patients were younger than 60 years old. Approximately 64.76% (465/718) had one or more comorbidities, and common comorbidities included non-alcoholic fatty liver disease (NAFLD), hyperlipidaemia, hypertension, diabetes mellitus (DM), chronic hepatitis B (CHB), hyperuricaemia, and gout. COVID-19 patients with comorbidities were older, especially those with chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD). Hypertension, DM, COPD, chronic kidney disease (CKD) and CVD were mainly found in severe COVID-19 patients. According to spearman correlation analysis the number of comorbidities was correlated positively with disease severity, the number of comorbidities and NAFLD were correlated positively with virus negative conversion time, hypertension, CKD and CVD were primarily associated with those who died, and the above-mentioned correlation existed independently of age. Risk factors included age, the number of comorbidities and hyperlipidaemia for disease severity, the number of comorbidities, hyperlipidaemia, NAFLD and COPD for the virus negative conversion time, and the number of comorbidities and CKD for prognosis. Number of comorbidities and age played a predictive role in disease progression and outcomes. Conclusion: Not only high number and specific comorbidities but also age are closely related to progression and poor prognosis in patients with COVID-19. These findings provide a reference for clinicians to focus on not only the number and specific comorbidities but also age in COVID-19 patients to predict disease progression and prognosis. Clinical Trial Registry: Chinese Clinical Trial Register ChiCTR2000034563.

13.
J Clin Virol ; 127: 104366, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32302954

RESUMO

BACKGROUND: In December 2019, Wuhan, China, experienced an outbreak of coronavirus (COVID-19). The number of cases has increased rapidly, but information on the clinical characteristics remains limited. OBJECTIVES: This paper describes the epidemiological and clinical characteristics of COVID-19. Early detection and identification of critically ill patients is necessary to facilitate scientific classification and treatment. STUDY DESIGN: This study included a retrospective, single-center case series of 99 consecutively hospitalized patients with confirmed COVID-19 at Chengdu Public Health Clinical Medical Center in Chengdu, China, from January 16 to February 20, 2020. The final date of follow-up was February 23, 2020. We collected and analyzed epidemiological, demographic, clinical, laboratory, radiological, and treatment data. We compared outcomes of critically ill patients and noncritically ill patients. RESULTS: Of the 99 hospitalized patients with COVID-19, the median age was 49 years (minimum, 3 months; maximum, 87 years) and 51 (52 %) were men; 42 (42 %) had traveled to or lived in Wuhan and 48 (49 %) had come into close contact with patients with new coronavirus pneumonia; 41 (41 %) patients had underlying disease. Common symptoms included fever (85 [86 %]), dry cough (84 [85 %]), and fatigue (72 [73 %]). We analyzed the clinical characteristics of patients. We expressed the measurement data as mean ±â€¯standard deviation. We collected data for age (49.39 ±â€¯18.45 years), number of hospital days (12.32 ±â€¯6.70 days), and laboratory indicators. We compared critically ill and noncritically ill patients: p-values for age, C-reactive protein, high-sensitivity troponin T, prothrombin time, fibrin degradation products, D-Dimer, and CD4+ count were p < 0.001; and p-values for hospital days, white blood cell, neutrophil, lymphocyte, creatine kinase isoenzyme, myoglobin, N-terminal brain natriuretic peptide, and CD8+ count were p < 0.05. CONCLUSIONS: We collected data from a single-center case series of 32 hospitalized patients who were critically ill with confirmed COVID-19 in Chengdu, China, and compared data with 67 noncritically ill patients. Elderly patients had chronic underlying diseases, notably cardiovascular disease. Higher C-reactive protein levels, higher levels of myocardial damage, and higher brain natriuretic peptide levels; lower white blood cells, neutrophils, and lymphocytes; and lower CD4 and CD8 counts could be used for early detection and identification of critically ill patients, and dynamic Data observation was more important than at a single moment.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Hospitalização/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Contagem de Linfócito CD4 , COVID-19 , Criança , Pré-Escolar , China/epidemiologia , Tosse/virologia , Estado Terminal , Fadiga/virologia , Feminino , Febre/virologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Resultado do Tratamento , Adulto Jovem
15.
Pharmaceutics ; 11(9)2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31450749

RESUMO

In this study, curcumin-loaded porous poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) were prepared and surface modified with red blood cell membranes (RBCM) to yield biomimetic RBCM-p-PLGA@Cur NPs. The NPs displayed a visible cell-membrane structure at their exterior and had a uniform size of 162 ± 3 nm. In vitro studies showed that drug release from non-porous PLGA NPs was slow and that much of the drug remained trapped in the NPs. In contrast, release was accelerated from the porous PLGA NPs, and after the RBCM coating, a sustained release over 48 h was obtained. Confocal microscopy and flow cytometry results revealed that the RBCM-p-PLGA NPs led to a greater cellular uptake by H22 hepatocarcinoma cells than the uncoated analogue NPs, but could avoid phagocytosis by macrophages. The drug-free formulations were highly biocompatible, while the drug-loaded systems were effective in killing cancer cells. RBCM-p-PLGA@Cur NPs possess potent anti-tumor activity in a murine H22 xenograft cancer model (in terms of reduced tumor volume and mass, as well as inducing apoptosis of tumor cells), and have no observable systemic toxicity. Overall, our study demonstrates that the use of the RBCM to cloak nanoscale drug delivery systems holds great promise for targeted cancer treatment, and can ameliorate the severe side effects currently associated with chemotherapy.

16.
Colloids Surf B Biointerfaces ; 173: 504-511, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30340178

RESUMO

Thermosensitive glucose-functionalized glycopolymers grafted gold nanoparticles (Glyco@GNPs) with good colloidal stability and thermosensitive in aqueous solution were fabricated by reversible addition-fragmentation chain transfer (RAFT) mediated one-pot synthesis. The formation of core-shell morphology with about a 60 nm gold core in diameter and a glycopolymer shell of about 80 nm in thickness was indicated by transmission electron microscopy (TEM). The recognition ability of the Glyco@GNPs toward lectin concannavalin A (Con A) was verified by ultraviolet-visible spectroscopy and dynamic light scattering (DLS). The good cytocompatibility of the glycopolymers and Glyco@GNPs was proven by MTT assay on L-929 cells. Glyco@GNPs could effectively inhibit hepatoma cells SMMC-7721 growth after recognizing Con A was also proved by MTT assay and flow cytometry assay.


Assuntos
Técnicas de Química Sintética , Concanavalina A/análise , Glucose/química , Glicoconjugados/química , Ouro/química , Nanopartículas Metálicas/química , Animais , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Concanavalina A/química , Fibroblastos/efeitos dos fármacos , Glicoconjugados/farmacologia , Hepatócitos/efeitos dos fármacos , Temperatura Alta , Humanos , Nanopartículas Metálicas/ultraestrutura , Metacrilatos/química , Camundongos , Polimerização , Soluções , Compostos de Vinila/química , Água/química
17.
J Neurooncol ; 140(2): 359-366, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30182160

RESUMO

PROPOSE: To explore the value of unmeasurable enhancement pattern of residual cavity in predicting survival at early stage after gross-total resection in high-grade glioma (HGG) patients. METHODS: This retrospective study enrolled consecutive 51 HGG patients with unmeasurable enhancement who underwent gross-total resection followed by concurrent chemoradiotherapy and adjuvant chemotherapy. We evaluated the enhancement patterns of residual cavity on contrast-T1WI made within 1 month after tumor resection (20 ± 3 days). The survival state of different enhancement was compared. RESULTS: Thin-linear, thick-linear and nodular enhancement were observed in 22 patients (43%), 10 patients (20%), and 19 patients (37%), respectively. The progression-free survival of patients with thin-linear (487, 151-887 days) was longer than those patients with thick-linear (277, 133-573 days), and nodular enhancement (210, 120-765 days) (P = 0.002). The overall survival of patients with thin-linear (774, 457-1343 days) was longer than those with thick-linear (462, 320-678 days), and nodular enhancement (326, 234-1393 days) (P = 0.002). There was no significant difference of orthogonal value between thick-linear and nodular enhancement (0.854), neither between grade III and IV with same enhancement patterns (P = 0.540, P = 0.720). CONCLUSIONS: The unmeasurable enhancement patterns in HGG patients within 1 month after gross-total resection, which might be better than the grade of tumor, holds a potential marker in survival state.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Período Pós-Operatório , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/efeitos da radiação , Encéfalo/cirurgia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Criança , Terapia Combinada , Feminino , Seguimentos , Glioma/mortalidade , Glioma/patologia , Glioma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Procedimentos Neurocirúrgicos , Prognóstico , Estudos Retrospectivos , Adulto Jovem
18.
J Neurooncol ; 137(3): 631-638, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29564748

RESUMO

To evaluate the prognostic value of fluid-attenuated inversion recovery (FLAIR) signal intensity of postoperative cavity on progression free survival (PFS) and overall survival (OS) in patients with high-grade gliomas (HGG). This study retrospectively enrolled 45 consecutive HGG patients. These patients had chemoradiotherapy after gross-total resection of tumors. Quantitative analysis of the FLAIR signal intensity in postoperative cavity and background was made. We evaluated the threshold value, accuracy, sensitivity, specificity, and survival state with this technique. The patients who progressed and patients who did not progress were 33 and 12 cases separately. The ratio of postoperative cavity and background (C-B) on FLAIR sequence in patients who progressed was higher than that of patients who did not progress (P = 0.014). The PFS of the patients who progressed was shorter than that of patients who did not progress (P = 0.008). The area under ROC curve, threshold, sensitivity, specificity of C-B ratio for predicting tumor progression were 0.875, 62.3, 69.7, 0.84, and 0.50% respectively. The PFS of lower signal group was much longer than that of higher signal group (P = 0.004). The OS of the patients with higher signal was shorter than that of patients with lower signal (P = 0.034). The increase of gray value of FLAIR in postoperative cavity may be used as an imaging marker for predicting tumor progression.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idoso , Encéfalo/cirurgia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/cirurgia , Criança , Progressão da Doença , Feminino , Seguimentos , Glioma/mortalidade , Glioma/patologia , Glioma/cirurgia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Período Pós-Operatório , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Análise de Sobrevida , Adulto Jovem
19.
Langmuir ; 34(9): 3058-3067, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29429347

RESUMO

A novel thermoresponsive hyperbranched multiarm copolymer with a hydrophobic hyperbranched poly[3-ethyl-3-(hydroxymethyl)oxetane] core and many poly(acrylamide- co-acrylonitrile) (P(AAm- co-AN)) arms was for the first time synthesized through a reversible addition-fragmentation chain-transfer polymerization. These copolymers show reversible, sharp, and controlled temperature-responsive phase transitions at the upper critical solution temperature (UCST) in water and electrolyte solution. It is the first report on the hyperbranched copolymers with a UCST transition. Two series copolymers with variable AN content (series A) and variable arm length (series B) were synthesized to study the influence of molecular structure on the UCST transition. It was found that the UCST of copolymers could be raised by increasing the AN content or decreasing the arm length. Most interestingly, the amplification effect of the hyperbranched topological structure leads to a broad change of the UCST from 33.2 to 65.2 °C with the little change of AN content (5.9%). On the basis of variable temperature nuclear magnetic resonance, dynamic light scattering, and transmission electron microscopy, a UCST transition mechanism, in combination with hydrophilic/hydrophobic balance and multimicelle aggregate (MMA), was proposed. This work enriches the UCST copolymer topology and may extend the knowledge on the structure-activity relationship as well as the mechanism of the UCST polymers.

20.
Macromol Rapid Commun ; 38(13)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28233415

RESUMO

This communication describes polymer vesicles self-assembled from hyperbranched polymers (branched polymersomes (BPs)) as scaffolds, conceptually mimicking the natural light-harvesting system in aqueous solution. The system is constructed with hydrophobic 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) as donors encapsulated in the hydrophobic hyperbranched cores of the vesicles and the hydrophilic Rhodamine B (RB) as acceptors incorporated on the surface of the vesicles through the cyclodextrin (CD)/RB host-guest interactions, through which the donors and acceptors are spatially separated to effectively avoid the self-quenching between donors. This vesicular light harvesting system has presented good energy transfer efficiency of about 80% in water, and can be used as the ink to write multiclolor letters. In addition, due to the giant dimension of BPs, the real-time fluorescent images of the vesicles under an optical microscope can be observed to prove the light-harvesting process. It is supposed that such a vesicular light-harvesting antenna can be used to construct artificial photosynthesis systems in the future.


Assuntos
Fotoquímica , Polímeros/síntese química , Água/química , Transferência de Energia , Interações Hidrofóbicas e Hidrofílicas , Luz
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