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1.
Eur J Nucl Med Mol Imaging ; 51(6): 1530-1543, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38189910

RESUMO

PURPOSE: Noninvasive quantifying activated hepatic stellate cells (aHSCs) by molecular imaging is helpful for assessing disease progression and therapeutic responses of liver fibrosis. Our purpose is to develop platelet-derived growth factor receptor ß (PDGFRß)-targeted radioactive tracer for assessing liver fibrosis by positron emission tomography (PET) imaging of aHSCs. METHODS: Comparative transcriptomics, immunofluorescence staining and flow cytometry were used to evaluate PDGFRß as biomarker for human aHSCs and determine the correlation of PDGFRß with the severity of liver fibrosis. The high affinity affibody for PDGFRß (ZPDGFRß) was labeled with gallium-68 (68Ga) for PET imaging of mice with carbon tetrachloride (CCl4)-induced liver fibrosis. Binding of the [68Ga]Ga-labeled ZPDGFRß ([68Ga]Ga-DOTA-ZPDGFRß) for aHSCs in human liver tissues was measured by autoradiography. RESULTS: PDGFRß overexpressed in aHSCs was highly correlated with the severity of liver fibrosis in patients and CCl4-treated mice. The 68Ga-labeled ZPDGFRß affibody ([68Ga]Ga-DOTA-ZPDGFRß) showed PDGFRß-dependent binding to aHSCs. According to the PET imaging, hepatic uptake of [68Ga]Ga-DOTA-ZPDGFRß increased with the accumulation of aHSCs and collagens in the fibrotic livers of mice. In contrast, hepatic uptake of [68Ga]Ga-DOTA-ZPDGFRß decreased with spontaneous recovery or treatment of liver fibrosis, indicating that the progression and therapeutic responses of liver fibrosis in mice could be visualized by PDGFRß-targeted PET imaging. [68Ga]Ga-DOTA-ZPDGFRß also bound human aHSCs and visualized fibrosis in patient-derived liver tissues. CONCLUSIONS: PDGFRß is a reliable biomarker for both human and mouse aHSCs. PDGFRß-targeted PET imaging could be used for noninvasive monitoring of liver fibrosis in mice and has great potential for clinical translation.


Assuntos
Radioisótopos de Gálio , Cirrose Hepática , Tomografia por Emissão de Pósitrons , Receptor beta de Fator de Crescimento Derivado de Plaquetas , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/metabolismo , Animais , Tomografia por Emissão de Pósitrons/métodos , Humanos , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Camundongos , Masculino , Células Estreladas do Fígado/metabolismo , Compostos Heterocíclicos com 1 Anel/química
2.
BMC Cancer ; 24(1): 57, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38200410

RESUMO

BACKGROUND: Anus preservation has been a challenge in the treatment of patients with low rectal adenocarcinoma (within 5 cm from the anal verge) because it is difficult to spare the anus with its functioning sphincter complex under the safe margin of tumour resection. Patients with dMMR/MSI-H can achieve a favourable complete response (CR) rate by using a single immune checkpoint inhibitor. For patients with pMMR/MSS/MSI-L, intensified neoadjuvant three-drug chemotherapy may be the preferred option for anal preservation. In addition, the watch and wait (W&W) strategy has been proven safe and feasible for patients with rectal cancer who achieve a clinical complete response (cCR). Therefore, we initiated this clinical trial to explore the optimal neoadjuvant treatment pattern for patients with low locally advanced rectal cancer (LARC) with different MMR/MSI statuses, aiming to achieve a higher cCR rate with the W&W strategy and ultimately provide more patients with a chance of anus preservation. METHODS: This is a randomised, controlled, open-label, multicentre phase III trial. Patients with clinical stage T2-4 and/or N + tumours located within 5 cm from the anal verge are considered eligible. Based on the results of pathological biopsy, the patients are divided into two groups: dMMR/MSI-H and pMMR/MSS. Patients in the dMMR/MSI-H group will be randomly allocated in a 1:1 ratio to either arm A (monoimmunotherapy) or arm B (short-course radiotherapy followed by monoimmunotherapy). Patients in the pMMR/MSS group will be initially treated with long-term pelvic radiation with concurrent capecitabine combined with irinotecan. Two weeks after the completion of chemoradiotherapy (CRT), the patients will be randomly allocated in a 1:1 ratio to arm C (XELIRI six cycle regime) or arm D (FOLFIRINOX nine cycle regime). The irinotecan dose will be adjusted according to the UGT1A1-genotype. After treatment, a comprehensive assessment will be performed to determine whether a cCR has been achieved. If achieved, the W&W strategy will be adopted; otherwise, total mesorectal excision (TME) will be performed. The primary endpoint is cCR with the maintenance of 12 months at least, determined using digital rectal examination, endoscopy, and rectal MRI or PET/CT as a supplementary method. DISCUSSION: APRAM will explore the best anus preservation model for low LARC, combining the strategies of consolidation chemotherapy, immunotherapy, and short-course radiotherapy, and aims to preserve the anus of more patients using W&W. Our study provides an accurate individual treatment mode based on the MMR/MSI status for patients with low LARC, and more patients will receive the opportunity for anus preservation under our therapeutic strategy, which would transform into long-term benefits. TRIAL REGISTRATION: Clinicaltrials.gov NCT05669092 (Registered 28th Nov 2022).


Assuntos
Adenocarcinoma , Neoplasias Encefálicas , Neoplasias Colorretais , Síndromes Neoplásicas Hereditárias , Neoplasias Pancreáticas , Neoplasias Retais , Humanos , Canal Anal , Protocolos de Quimioterapia Combinada Antineoplásica , Irinotecano , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase III como Assunto
3.
Int J Mol Sci ; 25(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474024

RESUMO

Traumatic brain injury (TBI) is defined as an injury to the brain by external forces which can lead to cellular damage and the disruption of normal central nervous system functions. The recently approved blood-based biomarkers GFAP and UCH-L1 can only detect injuries which are detectable on CT, and are not sensitive enough to diagnose milder injuries or concussion. Exosomes are small microvesicles which are released from the cell as a part of extracellular communication in normal as well as diseased states. The objective of this study was to identify the messenger RNA content of the exosomes released by injured neurons to identify new potential blood-based biomarkers for TBI. Human severe traumatic brain injury samples were used for this study. RNA was isolated from neuronal exosomes and total transcriptomic sequencing was performed. RNA sequencing data from neuronal exosomes isolated from serum showed mRNA transcripts of several neuronal genes. In particular, mRNAs of several olfactory receptor genes were present at elevated concentrations in the neuronal exosomes. Some of these genes were OR10A6, OR14A2, OR6F1, OR1B1, and OR1L1. RNA sequencing data from exosomes isolated from CSF showed a similar elevation of these olfactory receptors. We further validated the expression of these samples in serum samples of mild TBI patients, and a similar up-regulation of these olfactory receptors was observed. The data from these experiments suggest that damage to the neurons in the olfactory neuroepithelium as well as in the brain following a TBI may cause the release of mRNA from these receptors in the exosomes. Hence, olfactory receptors can be further explored as biomarkers for the diagnosis of TBI.


Assuntos
Concussão Encefálica , Lesões Encefálicas Traumáticas , Lesões Encefálicas , Vesículas Extracelulares , Neurônios Receptores Olfatórios , Receptores Odorantes , Humanos , Lesões Encefálicas Traumáticas/metabolismo , Vesículas Extracelulares/metabolismo , Neurônios Receptores Olfatórios/metabolismo , RNA , Biomarcadores , RNA Mensageiro , Perfilação da Expressão Gênica
4.
Molecules ; 29(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474592

RESUMO

This article reports three new two-photon absorption (TPA) materials that are quinolinium-carbazole derivates. They are 3-(N-methyl-4-ethylquinolinium iodide)-9-ethylcarbazole (M4), 3-(N-methyl-4-ethylquinolinium iodide)-9-ethylcarbazole (H2), and 3-(N-methyl-4-ethylquinolinium iodide)-9-ethylcarbazole (H4). Their TPA cross-sections are 491, 515, and 512 GM, respectively. Under the excitation of near-infrared light, their fluorescence emission is about 650 nm. The compounds can stain nucleic acid DNA with the same level of nuclear localization as Hoechst 33342. Under continuous irradiation with a near-infrared laser, the three new compounds showed less fluorescence decay than DAPI, and the average fluorescence decay rates were 0.016%/s, 0.020%/s, and 0.023%/s. They are expected to become new two-photon fluorescent probes of nucleic acid DNA because of their excellent performance.


Assuntos
Iodetos , Fótons , Fluorescência , Carbazóis , DNA , Raios Infravermelhos , Sondas de Ácido Nucleico , Corantes Fluorescentes
5.
Toxicol Appl Pharmacol ; 428: 115675, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34389318

RESUMO

Ammonia (NH3) is a recognized environmental contaminant around the world and has adverse effects on animal and human health. However, the mechanism of the renal toxicity of NH3 is not well understood. Pigs are considered an ideal model for biomedical and toxicological research because of the similarity to humans in physiological and biochemical basis. Therefore, in this study, twelve pigs were selected as research objects and randomly divided into two groups, namely the control group and the NH3 group. The formal experiment lasted 30 days. The effects of excessive NH3 inhalation on the kidney of fattening pig were evaluated by chemical analysis, ELISA, transcriptome analysis and real-time quantitative PCR (qRT-PCR) from the renal antioxidant level, renal function, blood ammonia content and gene level. Our results showed that excessive NH3 exposure could cause an increase in blood NH3 content, a reduction in renal GSH-Px, SOD and GSH, as well as an increase in MDA levels and an increase in serum creatinine, urea and uric acid levels. In addition, transcriptome analysis showed that NH3 exposure caused changes in 335 differentially expressed genes (DEGs) (including 126 up-regulated DEGs and 109 down-regulated DEGs). Some highly expressed DEGs were enriched into GO terms associated with immune function, oxidative stress, and apoptosis and were verified by qRT-PCR. The qRT-PCR results were comsistent with the transcriptome results. Our results indicated that NH3 exposure could cause changes in renal transcriptional profiles and kidney function, and induce kidney damage in the fattening pigs through oxidative stress, immune dysfunction and apoptosis. Our present study provides novel insights into the immunotoxicity mechanism of NH3 on kidney.


Assuntos
Amônia/toxicidade , Apoptose/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Terapia de Imunossupressão/métodos , Rim/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Amônia/administração & dosagem , Animais , Antioxidantes/metabolismo , Apoptose/fisiologia , Poluentes Ambientais/administração & dosagem , Poluentes Ambientais/toxicidade , Feminino , Exposição por Inalação/efeitos adversos , Rim/metabolismo , Rim/patologia , Estresse Oxidativo/fisiologia , Medição de Risco , Suínos
6.
Appl Microbiol Biotechnol ; 105(4): 1447-1460, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33528691

RESUMO

Due to their potent immune stimulation, tumor necrosis factor alpha (TNFα) variants with tumor-homing activity are attractive as novel antitumor drugs. The promising antitumor effect of NGR-TNFα in clinical trials triggered extensive interest in developing novel tumor-homing TNFα variants in recent years. Owing to its promising antitumor effect, NGR-TNFα is usually used as a control for newly developed tumor-homing TNFα variants. In our previous works, we produced a pericyte-targeting Z-TNFα at high levels using the Escherichia coli (E. coli) M15-pQE30 system. To further compare Z-TNFα and NGR-TNFα, we attempted to express NGR-TNFα using the same system. Surprisingly, native NGR-TNFα was expressed at a low (~ 0.2 mg/L) level in E. coli M15 containing the pQE30 plasmid. However, a single nucleotide mutation of C to G, resulting in a substitution of leucine (L) with valine (V) at the start of TNFα, increased the expression of NGR-TNFα by ~ 100 times through improving transcription. In addition, the amino acid substitution showed a little impact on the receptor binding, in vitro cytotoxicity, and in vivo antitumor effect of NGR-TNFα. As fusing NGR to the N-terminus of TNFα with a valine substitution did not reduce the protein yield, the TNFα gene with a C > G mutation might be used to prepare novel tumor-homing TNFα when the native TNFα-based variant is expressed at an extremely low level in E. coli. Notably, in addition to the mutated valine, the impact of N-terminal additional amino acids provided by pQE30 vector on the function of TNFα variant must be carefully evaluated. KEY POINTS : • A single nucleotide mutation increased the expression of NGR-TNFα by two orders. • Nucleotide mutation-induced amino acid substitution did not reduce NGR-TNFα activity.


Assuntos
Escherichia coli , Fator de Necrose Tumoral alfa , Linhagem Celular Tumoral , Escherichia coli/genética , Galanina/análogos & derivados , Mutação , Nucleotídeos , Oligopeptídeos/genética , Substância P/análogos & derivados , Transcrição Gênica , Fator de Necrose Tumoral alfa/genética
7.
Ecotoxicol Environ Saf ; 226: 112854, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34619474

RESUMO

Glyphosate (GLY) is the most widely used broad-spectrum, non-selective herbicide in the world, whose main degradation product is aminomethyl phosphonic acid (AMPA). Because of long-term and large-scale use, residual GLY and AMPA in the environment pose great environmental and human health threats. The purpose of this study is to evaluate the effects and mechanism of residual low-concentrations of GLY and AMPA in the environment on the development of zebrafish embryos. Zebrafish embryos were exposed to 0, 1, 10, 100, and 700 ng·mL-1 GLY and AMPA for 72 h (from 2 to 74 h post-fertilization). With increasing exposure dose, heart rates of both embryos and larvae showed a rising trend and obvious arrhythmia appeared. Defects in cardiac development and function of zebrafish juveniles may be related to altered transcription levels of cardiac development genes (TBX5, NKX2.5, BMP4) and apoptosis genes (Bcl-2, Bax). In addition, pericardial edema and bone deformation of zebrafish embryos may be caused by inhibition of Na+/K+-ATPase and Ca2+-ATPase after exposure to GLY and AMPA. The present results demonstrated that at typical environmental residual concentrations of GLY and AMPA had similar developmental toxicity in zebrafish embryos.


Assuntos
Embrião não Mamífero , Peixe-Zebra , Animais , Desenvolvimento Embrionário , Glicina/análogos & derivados , Humanos , Ácidos Fosforosos , Glifosato
8.
Apoptosis ; 25(1-2): 105-119, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894448

RESUMO

Liver fibrosis usually progresses to liver cirrhosis and even hepatocellular carcinoma. Since activated hepatic stellate cells (aHSCs) are responsible for liver fibrosis, reducing the quantity of aHSCs was considered the essential strategy for clinical antihepatofibrotic therapy. Due to the overexpression of TRAIL receptor 2 (DR5) in aHSCs, human TNF-related apoptosis-inducing ligand (hTRAIL) that could induce aHSCs apoptosis might be feasible for antihepatofibrotic therapy. However, the in vivo aHSCs-apoptosis-induction of hTRAIL is limited by its poor cell-targeting and a short half-life. In this study, we found that platelet-derived growth factor receptor ß (PDGFRß) was co-expressed with DR5 in aHSCs. And the ZPDGFRß affibody with high affinity for PDGFRß could bind aHSCs and, thus, accumulate in the fibrotic liver. ZPDGFRß was fused to hTRAIL to produce the fusion protein Z-hTRAIL. Compared to hTRAIL, Z-hTRAIL showed greater in vitro cell binding and apoptosis-induction in aHSCs. In addition, Z-hTRAIL induced apoptosis of aHSCs but spared other normal liver cells. In vivo, Z-hTRAIL accumulated preferentially in fibrotic livers and exerted greater effects than hTRAIL in inducing aHSCs apoptosis and reducing extracellular matrix (ECM) deposition. These results demonstrated that the antihepatofibrotic effect of hTRAIL was improved by PDGFRß-targeted delivery. To enhance its pharmacokinetics, Z-hTRAIL was modified with 10 kDa polyethylene glycol (PEG), which significantly (30-40 times) prolonged its half-life. The PEGylated long-acting Z-hTRAIL was more potent than the native Z-hTRAIL in regressing liver fibrosis. These results suggest that the aHSC-targeting and long-acting Z-hTRAIL might serve as a novel tool for antihepatofibrotic therapy.


Assuntos
Células Estreladas do Fígado/metabolismo , Cirrose Hepática/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Feminino , Células Estreladas do Fígado/citologia , Humanos , Cirrose Hepática/genética , Cirrose Hepática/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética
9.
Plant Cell Environ ; 43(11): 2650-2665, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32744331

RESUMO

Rising tropospheric ozone affects the performance of important cereal crops thus threatening global food security. In this study, genetic variation of wheat regarding its physiological and yield responses to ozone was explored by exposing a diversity panel of 150 wheat genotypes to elevated ozone and control conditions throughout the growing season. Differential responses to ozone were observed for foliar symptom formation quantified as leaf bronzing score (LBS), vegetation indices and yield components. Vegetation indices representing the carotenoid to chlorophyll pigment ratio (such as Lic2) were particularly ozone-responsive and were thus considered suitable for the non-invasive diagnosing of ozone stress. Genetic variation in ozone-responsive traits was dissected by a genome-wide association study (GWAS). Significant marker-trait associations were identified for LBS on chromosome 5A and for vegetation indices (NDVI and Lic2) on chromosomes 6B and 6D. Analysis of linkage disequilibrium (LD) in these chromosomal regions revealed distinct LD blocks containing genes with a putative function in plant redox biology such as cytochrome P450 proteins and peroxidases. This study gives novel insight into the natural genetic variation in wheat ozone response, and lays the foundation for the molecular breeding of tolerant wheat varieties.


Assuntos
Variação Genética/genética , Ozônio/metabolismo , Triticum/genética , Adaptação Fisiológica/genética , Genes de Plantas/genética , Estudos de Associação Genética , Loci Gênicos/genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único/genética
10.
BMC Cancer ; 20(1): 862, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894078

RESUMO

BACKGROUND: The aim of this study is to assess biplane transrectal ultrasonography (TRUS) plus ultrasonic elastosonography (UE) and contrast-enhanced ultrasonography (CEUS) in T staging of rectal cancer. METHODS: Between March 2016 and January 2019, 66 rectal cancer patients who completed biplane TRUS plus UE and CEUS for preoperative workup and were treated by primary total mesorectal excision (TME) were retrospectively analyzed. RESULTS: The accuracy of TRUS plus UE and CEUS in all T staging of rectal cancer was 69.7%. The highest accuracy was achieved in the T3 stage (87.5%), while it was 71.4 and 50.0% in the T1 and T2 stage, respectively. The mean sizes of uT1-T2 lesions and uT3-T4 lesions were 30.0 ± 10.6 mm (range, 10.0-55.0) and 40.2 ± 11.2 mm (range, 14.0-57.0), respectively (p < 0.001). According to the receiver operating characteristic (ROC) curve to predict pT stages (pT1,2 vs. pT3), the optimal cut-off value of lesions in greatest dimension was 28.5 mm by TRUS with areas under the curve (AUC) of 0.769, and the optimal cut-off values of peak systolic velocity (PSV) and resistive index (RI) were 18.8 cm/sec and 0.645, respectively. The AUCs of PSV and RI were 0.588 and 0.555, respectively. CONCLUSIONS: Diagnostic accuracy of TRUS plus UE and CEUS in T staging of rectal cancer does not reach the excellent published study results, especially for patients with early rectal cancer. Tumor sizes, PSV and RI are useful additions for TRUS in T staging of rectal cancer.


Assuntos
Endossonografia , Neoplasias Retais/diagnóstico , Reto/diagnóstico por imagem , Ultrassom Focalizado Transretal de Alta Intensidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cintilografia/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Reto/patologia , Estudos Retrospectivos
11.
BMC Genet ; 21(1): 45, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32326905

RESUMO

BACKGROUND: Development of wheat cultivars with multiple disease resistance and high quality are major objectives in modern wheat breeding programs. Gene stacking is an efficient approach to achieve this target. In this study, we pyramided yellow rust resistance gene (Yr26), powdery mildew resistance gene (ML91260) and high-molecular-weight glutenin subunits Dx5 + Dy10 into the dwarf mutant of an elite wheat cultivar, Xiaoyan22. RESULTS: Six pyramided wheat lines were obtained by molecular marker-assisted selection (MAS) and field evaluation of disease resistance. The desirable agronomic traits of pyramided lines, their identity with the original cultivar Xiaoyan22 except for plant height, tiller number and disease resistance, was achieved in this study. Meanwhile, the yield of pyramided lines is higher than Xiaoyan22 in the field test. In addition, analysis of flour quality indicated that the dough stability time of pyramided lines was longer than that of Xiaoyan22. CONCLUSIONS: Six pyramided wheat lines with two disease resistance and high quality were achieved in this study. It is feasible to improve multiple agronomic traits simultaneously by rational application of MAS.


Assuntos
Resistência à Doença/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Triticum/genética , Basidiomycota/patogenicidade , Genes de Plantas , Glutens/genética , Doenças das Plantas/microbiologia , Triticum/microbiologia
12.
Biomacromolecules ; 21(10): 4017-4029, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-32804484

RESUMO

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an attractive antitumor drug candidate for precision cancer therapy due to its superior selective cytotoxicity in a variety of tumor cells. However, the clinical application of TRAIL in cancer therapy has been limited by its poor tumor-homing capacities and short half-life. Herein, we designed a tridomain TRAIL variant, Z-ABD-TRAIL, by sequentially fusing the platelet-derived growth factor receptor beta (PDGFRß)-specific affibody ZPDGFRß and an albumin-binding domain (ABD) to the N-terminus of TRAIL. The fusion protein Z-ABD-TRAIL was produced as a soluble protein with high yield in Escherichia coli (E. coli). The ZPDGFRß domain provided Z-ABD-TRAIL with PDGFRß-binding properties and thus promoted its tumor homing via the engagement of PDGFRß-expressing pericytes on tumor microvessels. ABD-mediated binding of Z-ABD-TRAIL to albumin in the blood endowed TRAIL with long-lasting (>72 h for Z-ABD-TRAIL vs <0.5 h for TRAIL) abilities to kill tumor cells. Although the in vitro cytotoxicity of Z-ABD-TRAIL in tumor cells was similar to that of the parent TRAIL, the in vivo tumor uptake, apoptosis-inducing ability, and antitumor effect of Z-ABD-TRAIL were much greater than those of TRAIL, indicating that ZPDGFRß-mediated tumor homing and ABD-introduced albumin binding significantly improved the pharmacodynamics of TRAIL. In addition, repeated injection of high-dose Z-ABD-TRAIL showed no obvious acute toxicity in mice. These results demonstrate that the newly designed tridomain Z-ABD-TRAIL is a promising agent for precision cancer therapy.


Assuntos
Escherichia coli , Ligante Indutor de Apoptose Relacionado a TNF , Albuminas , Animais , Apoptose , Linhagem Celular Tumoral , Preparações de Ação Retardada , Camundongos , Ligante Indutor de Apoptose Relacionado a TNF/genética
13.
Analyst ; 144(4): 1245-1252, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30539190

RESUMO

We report three new types of two-photon-absorption compounds, which contain a carbazole center core linked to two quinolinium units. Their action two-photon absorption cross-sections are 287.13, 267.75, and 236.25 GM. Under near-infrared excitation, their fluorescence emissions are observed at approximately 650 nm. The new compounds can stain deoxyribonucleic acid (DNA) with the same level of nuclear localization as that of Hoechst 33342. Under continuous irradiation with a near-infrared laser, the fluorescence decays of the three new compounds were less than those of 4,6-diamidino-2-phenylindole; the average fluorescence decay rates were 0.014, 0.015, and 0.014% s-1. They are expected to become new two-photon fluorescent probes of DNA.


Assuntos
Carbazóis/química , Carbazóis/metabolismo , DNA/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Fótons , Compostos de Quinolínio/química , Células 3T3 , Animais , Camundongos , Fenômenos Ópticos
14.
Virol J ; 15(1): 56, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29587789

RESUMO

BACKGROUND: Hendra virus and Nipah virus are zoonotic viruses that have caused severe to fatal disease in livestock and human populations. The isolation of Cedar virus, a non-pathogenic virus species in the genus Henipavirus, closely-related to the highly pathogenic Hendra virus and Nipah virus offers an opportunity to investigate differences in pathogenesis and receptor tropism among these viruses. METHODS: We constructed full-length cDNA clones of Cedar virus from synthetic oligonucleotides and rescued two replication-competent, recombinant Cedar virus variants: a recombinant wild-type Cedar virus and a recombinant Cedar virus that expresses a green fluorescent protein from an open reading frame inserted between the phosphoprotein and matrix genes. Replication kinetics of both viruses and stimulation of the interferon pathway were characterized in vitro. Cellular tropism for ephrin-B type ligands was qualitatively investigated by microscopy and quantitatively by a split-luciferase fusion assay. RESULTS: Successful rescue of recombinant Cedar virus expressing a green fluorescent protein did not significantly affect virus replication compared to the recombinant wild-type Cedar virus. We demonstrated that recombinant Cedar virus stimulated the interferon pathway and utilized the established Hendra virus and Nipah virus receptor, ephrin-B2, but not ephrin-B3 to mediate virus entry. We further characterized virus-mediated membrane fusion kinetics of Cedar virus with the known henipavirus receptors ephrin-B2 and ephrin-B3. CONCLUSIONS: The recombinant Cedar virus platform may be utilized to characterize the determinants of pathogenesis across the henipaviruses, investigate their receptor tropisms, and identify novel pan-henipavirus antivirals. Moreover, these experiments can be conducted safely under BSL-2 conditions.


Assuntos
Efrina-B2/metabolismo , Infecções por Henipavirus/virologia , Henipavirus/fisiologia , Receptores Virais/metabolismo , Fusão Celular , Linhagem Celular , Efeito Citopatogênico Viral , Genes Reporter , Proteínas de Fluorescência Verde/genética , Henipavirus/genética , Henipavirus/metabolismo , Henipavirus/patogenicidade , Infecções por Henipavirus/metabolismo , Interferon Tipo I/genética , Testes de Neutralização , Ligação Proteica , Recombinação Genética , Genética Reversa , Proteínas do Envelope Viral/metabolismo , Tropismo Viral , Internalização do Vírus , Replicação Viral
15.
PLoS Pathog ; 11(12): e1005322, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26646856

RESUMO

Nipah virus (NiV) is a paramyxovirus that infects host cells through the coordinated efforts of two envelope glycoproteins. The G glycoprotein attaches to cell receptors, triggering the fusion (F) glycoprotein to execute membrane fusion. Here we report the first crystal structure of the pre-fusion form of the NiV-F glycoprotein ectodomain. Interestingly this structure also revealed a hexamer-of-trimers encircling a central axis. Electron tomography of Nipah virus-like particles supported the hexameric pre-fusion model, and biochemical analyses supported the hexamer-of-trimers F assembly in solution. Importantly, structure-assisted site-directed mutagenesis of the interfaces between F trimers highlighted the functional relevance of the hexameric assembly. Shown here, in both cell-cell fusion and virus-cell fusion systems, our results suggested that this hexamer-of-trimers assembly was important during fusion pore formation. We propose that this assembly would stabilize the pre-fusion F conformation prior to cell attachment and facilitate the coordinated transition to a post-fusion conformation of all six F trimers upon triggering of a single trimer. Together, our data reveal a novel and functional pre-fusion architecture of a paramyxoviral fusion glycoprotein.


Assuntos
Infecções por Henipavirus/metabolismo , Vírus Nipah/química , Proteínas do Envelope Viral/química , Internalização do Vírus , Cristalografia por Raios X , Eletroforese em Gel de Poliacrilamida , Células HEK293 , Humanos , Mutagênese Sítio-Dirigida , Vírus Nipah/metabolismo , Conformação Proteica , Proteínas do Envelope Viral/metabolismo
16.
BMC Cancer ; 17(1): 182, 2017 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-28279170

RESUMO

BACKGROUND: In this era of oxaliplatin-based adjuvant therapy, the optimal sequence in which chemoradiotherapy should be administered for pathological stage N2 rectal cancer is unknown. The aim of this study was to investigate this sequence. METHODS: In the primary adjuvant concurrent chemoradiotherapy (A-CRT) group (n = 71), postoperative concurrent chemoradiotherapy was administered before adjuvant chemotherapy. In the primary adjuvant chemotherapy (A-CT) group (n = 43), postoperative concurrent chemoradiotherapy was administered during or after adjuvant chemotherapy. Postoperative radiotherapy comprised 45-50.4 Gy in 25-28 fractions. Concurrent chemotherapy comprised two cycles of oral capecitabine (1,600 mg/m2) on days 1-14 and 22-35. Patients receiving adjuvant chemotherapy with four or more cycles of XELOX (oxaliplatin plus capecitabine) or eight or more cycles of FOLFOX (fluorouracil, leucovorin, and oxaliplatin) were included. RESULTS: Between June 2005 and December 2013, data for 114 qualified rectal cancer patients were analyzed. The percentages of patients in whom treatment failed in the A-CRT and A-CT groups were 33.8% and 16.3%, respectively (p = 0.042). More patients had distant metastases in the A-CRT group than in the A-CT group (32.4% vs. 14.3%, p = 0.028). Multivariate analysis indicated that the sequence in which chemoradiotherapy was administered (A-CT vs. A-CRT) was an independent prognostic factor for both estimated disease-free survival [hazard ratio (HR) 0.345, 95% confidence interval (CI) 0.137-0.868, p = 0.024] and estimated distant metastasis-free survival (HR 0.366, 95% CI 0.143-0.938, p = 0.036). CONCLUSIONS: In pathological stage N2 rectal cancer patients, administering adjuvant chemotherapy before chemoradiotherapy led to a lower rate of treatment failure, especially with respect to distant metastasis. Adjuvant chemotherapy prescribed as early as possible might benefit this cohort of patients in this era of oxaliplatin-based adjuvant therapy.


Assuntos
Quimiorradioterapia Adjuvante/métodos , Quimioterapia Adjuvante/métodos , Compostos Organoplatínicos/administração & dosagem , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Capecitabina/administração & dosagem , Capecitabina/uso terapêutico , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/uso terapêutico , Humanos , Leucovorina/administração & dosagem , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Resultado do Tratamento , Adulto Jovem
17.
Mol Pharm ; 14(2): 502-512, 2017 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-28029256

RESUMO

The poor in vivo potencies of most therapeutic proteins might be attributed to their short serum half-lives. PEGylation is a well-established method and has been clinically proven to improve pharmacokinetics. mmTRAIL exhibited supercytotoxicity in a variety of tumor cells, but its serum half-life was less than 10 min in mice. Here, mmTRAIL-5K, mmTRAIL-10K, and mmTRAIL-20K were produced by N-terminus-specific PEGylation of mmTRAIL with 5, 10, or 20 kDa mPEG, respectively. The particle sizes of mmTRAIL-5K, mmTRAIL-10K, and mmTRAIL-20K were 9.09 ± 2.76, 12.62 ± 4.05, and 15.68 ± 4.95 nm, which were higher than the threshold (∼7 nm) of renal clearance. Accordingly, mmTRAIL-5K exhibited a serum half-life of 30 min only 3 times longer than that of mmTRAIL. However, both mmTRAIL-10K and mmTRAIL-20K exhibited similar serum half-lives ranging from 350 to 400 min, indicating that PEGylation with 10 or 20 kDa mPEG significantly improved the pharmacokinetics of mmTRAIL. However, death receptor binding of mmTRAIL-20K was reduced 5- to 8-fold, resulting in a 3-fold reduction of cytotoxicity. Additionally, repeated administration of mmTRAIL-20K elicited both mPEG-specific IgG and IgM antibody responses in rats. In contrast, the receptor binding and cytotoxicity of mmTRAIL-10K were similar to those of mmTRAIL. Repeated administration of mmTRAIL-10K did not obviously stimulate mPEG-specific antibody responses in rats and rhesus monkeys. Of the three PEGylated mmTRAIL analogues, mmTRAIL-10K exerted the greatest tumor suppression in mice bearing human tumor xenografts. These results demonstrated that conjugation of mmTRAIL to 10 kDa mPEG was better than that to 5 or 20 kDa mPEG for enhancing antitumor effects.


Assuntos
Anticorpos/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacocinética , Polietilenoglicóis/química , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Animais , Antineoplásicos/sangue , Linhagem Celular Tumoral , Meia-Vida , Humanos , Imunoglobulina G/metabolismo , Imunoglobulina M/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ligação Proteica/fisiologia , Ratos , Ratos Wistar
18.
J Virol ; 88(9): 4624-31, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24522928

RESUMO

UNLABELLED: Hendra virus (HeV) is a zoonotic emerging virus belonging to the family Paramyxoviridae. HeV causes severe and often fatal respiratory and/or neurologic disease in both animals and humans. Currently, there are no licensed vaccines or antiviral drugs approved for human use. A number of animal models have been developed for studying HeV infection, with the African green monkey (AGM) appearing to most faithfully reproduce the human disease. Here, we assessed the utility of a newly developed recombinant subunit vaccine based on the HeV attachment (G) glycoprotein in the AGM model. Four AGMs were vaccinated with two doses of the HeV vaccine (sGHeV) containing Alhydrogel, four AGMs received the sGHeV with Alhydrogel and CpG, and four control animals did not receive the sGHeV vaccine. Animals were challenged with a high dose of infectious HeV 21 days after the boost vaccination. None of the eight specifically vaccinated animals showed any evidence of clinical illness and survived the challenge. All four controls became severely ill with symptoms consistent with HeV infection, and three of the four animals succumbed 8 days after exposure. Success of the recombinant subunit vaccine in AGMs provides pivotal data in supporting its further preclinical development for potential human use. IMPORTANCE: A Hendra virus attachment (G) glycoprotein subunit vaccine was tested in nonhuman primates to assess its ability to protect them from a lethal infection with Hendra virus. It was found that all vaccinated African green monkeys were completely protected against subsequent Hendra virus infection and disease. The success of this new subunit vaccine in nonhuman primates provides critical data in support of its further development for future human use.


Assuntos
Vírus Hendra/imunologia , Infecções por Henipavirus/prevenção & controle , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Adjuvantes Imunológicos/administração & dosagem , Hidróxido de Alumínio/administração & dosagem , Animais , Chlorocebus aethiops , Modelos Animais de Doenças , Vírus Hendra/genética , Infecções por Henipavirus/patologia , Oligodesoxirribonucleotídeos/administração & dosagem , Análise de Sobrevida , Vacinação/métodos , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Proteínas do Envelope Viral/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
19.
Emerg Infect Dis ; 20(3): 372-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24572697

RESUMO

In recent years, the emergence of several highly pathogenic zoonotic diseases in humans has led to a renewed emphasis on the interconnectedness of human, animal, and environmental health, otherwise known as One Health. For example, Hendra virus (HeV), a zoonotic paramyxovirus, was discovered in 1994, and since then, infections have occurred in 7 humans, each of whom had a strong epidemiologic link to similarly affected horses. As a consequence of these outbreaks, eradication of bat populations was discussed, despite their crucial environmental roles in pollination and reduction of the insect population. We describe the development and evaluation of a vaccine for horses with the potential for breaking the chain of HeV transmission from bats to horses to humans, thereby protecting horse, human, and environmental health. The HeV vaccine for horses is a key example of a One Health approach to the control of human disease.


Assuntos
Saúde Ambiental , Vírus Hendra/imunologia , Infecções por Henipavirus/prevenção & controle , Doenças dos Cavalos/prevenção & controle , Vacinas Virais/imunologia , Zoonoses/prevenção & controle , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Feminino , Furões , Cobaias , Vírus Hendra/genética , Doenças dos Cavalos/patologia , Doenças dos Cavalos/virologia , Cavalos , Humanos , Imunização , Testes de Neutralização , Zoonoses/patologia , Zoonoses/virologia
20.
Plant Sci ; 338: 111924, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992899

RESUMO

Tropospheric ozone accelerates senescence and shortens grain filling, consequently affecting the remobilization and allocation efficiency of aboveground biomass and nutrients into grains in cereal crops. This study investigated carbon (C) and nitrogen (N) concentrations repeatedly in shoot biomass during the growth period and in grain after the harvest in eighteen wheat genotypes under control and ozone treatments in open-top chambers. Season-long ozone fumigation was conducted at an average ozone concentration of 70 ppb with three additional acute ozone episodes of around 150 ppb. Although there were no significant differences in straw C and N concentrations between the two treatments, the straw C:N ratio was significantly increased after long-term ozone fumigation, and the grain C:N ratio decreased under elevated ozone without significance. Grain N concentrations increased significantly under ozone stress, whereas N yield declined significantly due to grain yield losses induced by ozone. Moreover, different indicators of N use efficiency were significantly reduced with the exception of N utilization efficiency (NUtE), indicating that elevated ozone exposure reduced the N absorption from soil and allocation from vegetative to reproductive organs. The linear regression between straw C:N ratio and productivity indicated that straw C:N was not a suitable trait for predicting wheat productivity due to the low coefficient of determination (R2). Nitrogen harvest index (NHI) was not significantly affected by ozone stress among all genotypes. However, elevated ozone concentration changed the relationship between harvest index (HI) and NHI, and the reduced regression slope between them indicated that ozone exposure significantly affected the relationship of N and biomass allocation into wheat grains. The cultivar "Jenga" showed optimal ozone tolerance due to less yield reduction and higher NUE after ozone exposure. The genotypes with higher nutrient use efficiencies are promising to cope with ozone-induced changes in nitrogen partitioning.


Assuntos
Ozônio , Triticum , Ozônio/farmacologia , Nitrogênio , Carbono , Estações do Ano , Grão Comestível
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