Functionalized Green Carbon dots for Specific Detection of Copper in Human Serum Samples and Living Cells.

Intracellular copper ion (Cu2+) is irreplaceable and essential in regulation of physiological and biological processes, while excessive copper from bioaccumulation may cause potential hazards to human health. Hence, effective and sensitive recognition is urgently significant to prevent over-intake of copper. In this work, a novel highly sensitive and green carbon quantum dots (Green-CQDs) were synthesized by a low-cost and facile one-step microwave auxiliary method, which utilized gallic acid, carbamide and PEG400 as carbon source, nitrogen source and surface passivation agent, respectively. The decreased fluorescence illustrated excellent linear relationship with the increasing of Cu2+ concentration in a wide range. Substantial surface amino and hydroxyl group introduced by PEG400 significantly improved selectivity and sensitivity of Green-CQDs. The surface amino chelation mechanism and fluorescence internal filtration effect were demonstrated by the restored fluorescence after addition of EDTA. Crucially, the nanosensor illustrated good cell permeability, high biocompatibility and recovery rate, significantly practical application in fluorescent imaging and biosensing of intracellular Cu2+ in HepG-2 cells, which revealed a potential and promising biological applications in early diagnosis and treatment of copper ion related disease.

Dysregulated expression of microRNA involved in resistance to osimertinib in EGFR mutant non-small cell lung cancer cells.

Background: An increasing amount of evidence has confirmed that the altered expression of microRNAs (miRNAs) is critical to the mechanism underlying primary and even acquired resistance to tyrosine kinase inhibitors (TKIs). However, studies on the linkage between the altered miRNAs expression and osimertinib resistance are few, and the effect of miRNAs in this context is still unclear. In the light of this, we hypothesized that the differential expression of multiple miRNAs is the driver in the osimertinib resistance process. Thus, the aim of our study was to find differentially expressed miRNAs in non-small cell lung cancer cells resistant to osimertinib. Methods: An AZD9291(Osimertinib)-resistant cell line model was constructed, and the differential miRNAs between epidermal growth factor receptor (EGFR)-sensitive cell lines A549 and H1975 and the corresponding drug-resistant cell lines were identified via biosynthesis analysis. Results: In the A549 osimertinib-resistant cell line, 93 miRNAs were upregulated and 94 miRNAs were downregulated. In the H1975 osimertinib-resistant cell line, 124 miRNAs were upregulated and 53 miRNAs were downregulated. Finally, 7 significantly different miRNAs were screened using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Conclusions: This study on the mechanism of target therapy in lung cancer systematically and comprehensively examined the miRNAs involved in osimertinib resistance. It was found that miR-708-5p, miR-708-3p, miR-10395-3p, miR-7704 miR-34a-5p, miR-19b-1-5p, and miR-219a-5p may play key roles in osimertinib resistance.

A mitochondria-targeting self-assembled carrier-free lonidamine nanodrug for redox-activated drug release to enhance cancer chemotherapy.

Mitochondria play a vital role in maintaining cellular homeostasis. In recent years, studies have found that mitochondria have an important role in the occurrence and development of tumors, and targeting mitochondria has become a new strategy for tumor treatment. Lonidamine (LND), as a hexokinase inhibitor, can block the energy supply and destroy mitochondria. However, poor water solubility and low mitochondrial selectivity limit its clinical application. To overcome these obstacles, we report redox-activated self-assembled carrier-free nanoparticles (Cy-TK-LND NPs) based on a small molecule prodrug, in which photosensitizer IR780 (Cy) which targets mitochondria is conjugated to LND via a sensitive thioketal (TK) linker. Intracellular oxidative stress induced by laser radiation leads to the responsive cleavage of Cy-TK-LND NPs, facilitating the release of free LND into mitochondria. Subsequently, LND damages mitochondria, triggering the apoptosis pathway. The results show the effective killing effect of Cy-TK-LND NPs on cancer cells in vitro and in vivo. The IC50 value of irradiated Cy-TK-LND NPs is 5-fold lower than that of free LND. Moreover, tumor tissue section staining results demonstrate that irradiated Cy-TK-LND NPs induce necrosis and apoptosis of tumor cells, upregulate cytochrome C and pro-apoptotic Bax, and downregulate anti-apoptotic Bcl-2. Generally, Cy-TK-LND NPs exhibit efficient mitochondria-targeted delivery to improve the medicinal availability of LND. Accordingly, such a carrier-free prodrug-based nanomedicine holds promise as an effective cancer chemotherapy strategy.

Novel Green Fluorescent Probe Stem From Carbon Quantum Dots for Specific Recognition of Tyrosinase in Serum and Living Cells.

Tyrosinase (TYR), an important biomarker for melanoma, offered significant information early detection of melanoma and may decrease the likelihood of mortality. Therefore, this article constructed a highly sensitive and selective green fluorescent functionalized carbon quantum dots (TYR-CQDs) for tyrosinase (TYR) activity detection by one-step hydrothermal protocol utilizing catechol, citric acid and urea as precursors. The prepared TYR-CQDs illustrated excellent linear relationship and broad linear range with a low detection limit, which exhibited high accuracy and recovery in quantitative determination of TYR in human serum samples. Furthermore, the TYR-CQDs had successfully realized intracellular TYR detection owing to excellent biocompatibility, high anti-interference ability and good cellular imaging capability, suggesting the potential biomedical applications in early diagnosis of melanoma and other tyrosinase-related diseases.

Baicalin attenuates gentamicin-induced cochlear hair cell ototoxicity.

Gentamicin can lead to cochlear hair cells associated ototoxicity by inducing apoptosis and oxidative stress, which can be alleviated by baicalin, one flavonoid extracted from the root of Scutellaria baicalensis. The role of baicalin in protecting gentamicin-induced hearing loss is unclear. Interference with oxidative stress was investigated in this study using House Ear Institute-Organ of Corti1 (HEI-OC1) cells, which were simultaneously treated with baicalin (0-400 µm) and gentamicin (0.2 or 1 mm). MTT was used to assay cell viability and apoptosis was detected with Annexin V-fluorescein isothiocyanate staining. The production of reactive oxygen species was indicated by 2,7-dichlorofluorescein diacetate fluorescence intensity and mitochondrial depolarization was assayed by JC1-mitochondrial membrane potential assay. Poly(ADP-ribose) polymerase (PARP), cleaved-caspase 3 and cleaved-PARP expression were analyzed with western blot. Baicalin improved the viability of HEI-OC1 cells and significantly reduced the oxidative stress and mitochondrial depolarization compared with the gentamicin treatment group. Gentamicin treatment increased the activation of PARP and caspase-3, while such an increase could be downregulated by baicalin. Baicalin attenuates gentamicin-induced cochlear hair cells ototoxicity, and such inhibition may be mediated by the regulation of reactive oxygen species production, mitochondrial depolarization, and caspase-3 and PARP activation.

Conformance Assessment of PD-L1 Expression Between Primary Tumour and Nodal Metastases in Non-Small-Cell Lung Cancer.

INTRODUCTION: Programmed death-ligand 1 (PD-L1) expression as measured by immunohistochemistry (IHC) has been employed to predict the efficacy of anti-PD-1/PD-L1 therapy. Nevertheless, heterogeneous PD-L1 expression represents a challenge for the selection of patients for anti-PD-1/PD-L1 therapy. METHODS: PD-L1 expression using clone 22C3 in 76 resected non-small-cell lung cancer and paired nodal metastases was assessed and classified according to the proportion of immunostained tumour cells using cutoff values of 1%, 5%, and 50%. RESULTS: The concordance rates for PD-L1 expression between primary and metastatic lymph nodes (N1) at these cutoff values were 67.7% (21/31) (Kappa value: 0.455, p<0.000), 60.0% (15/25) (Kappa value: 0.668, p<0.000), and 62.5% (5/8) (Kappa value: 0.497, p<0.000). In 36 paired N1 lymph nodes and N2 lymph nodes, 54.5% (6/11) (Kappa value: 0.625, p<0.000) of cases of PD-L1 expression were coincident at cutoffs of 1%. If stratified by adenocarcinoma and squamous cell carcinoma, 87.5% (14/16) (Kappa value: 0.830, p<0.000) of cases at the 1% cutoff and 46.7% (7/15) (Kappa value: 0.324, p<0.000) of cases at the 1% cutoff were coincident. CONCLUSION: The results of this study demonstrate that the concordance of PD-L1 expression between primary tumour and nodal metastases is low in non-small-cell lung cancer but is high in adenocarcinoma. Our results also suggest that PD-L1 expression in either lymph nodes or tumour tissues does not predict survival. PD-L1 detection in metastatic lymph nodes is not a suitable replacement for PD-L1 detection in the primary lesion.

Risk of venous and arterial thromboembolic events associated with anti-VEGF agents in advanced non-small-cell lung cancer: a meta-analysis and systematic review.

AIMS: To assess the incidence and risk of arterial and venous thromboembolic events (ATEs and VTEs) associated with antivascular endothelial growth factor (VEGF) agents, including VEGF receptor-tyrosine kinase inhibitors and VEGF monoclonal antibodies, in advanced non-small-cell lung cancer (NSCLC) patients. METHODS: We performed a broad search of PubMed for relevant trials. Prospective randomized trials evaluating therapy with or without anti-VEGF agents in patients with advanced NSCLC were included for analysis. Data on VTEs and ATEs were extracted. The overall incidence, Peto odds ratio (Peto OR), and 95% confidence intervals (CIs) were pooled according to the heterogeneity of included trials. RESULTS: A total of 13,436 patients from 23 trials were included for analysis. Our results showed that anti-VEGF agents significantly increased the risk of developing high-grade ATEs (Peto OR: 1.44, 95% CI: 1.00-2.07, P=0.048), but not for all-grade ATEs (Peto OR: 0.94, 95% CI: 0.56-1.59, P=0.82) compared with controls. Additionally, no increased risk of all-grade and high-grade VTEs (Peto OR: 0.94, 95% CI: 0.67-1.31, P=0.71 and Peto OR: 0.95, 95% CI: 0.73-1.22, P=0.67, respectively) was observed in advanced NSCLC patients receiving anti-VEGF agents. CONCLUSION: The use of anti-VEGF agents in advanced NSCLC patients significantly increased the risk of high-grade ATEs, but not for VTEs. Clinicians should be aware of the risk of severe ATEs with administration of these drugs in advanced NSCLC patients.

Is mitochondrial tRNA Cys G5821A a deleterious mutation?

Although there are increasing reports showed a positive link between mitochondrial tRNACys G5821A mutation and mitochondrial diseases. However, its role remained controversial. In this paper, we took a comprehensive data analysis concerning this mutation and clinical diseases. Our data indicated that this mutation lacked an evolutionary conservation and did not get involved in the thermodynamic change of tRNACys gene. Therefore, based on these observations, we proposed that G5821A mutation is not deleterious mutation.

[Math1 gene therapy for kanamycin and furosemide-induced deaf guinea pigs].

OBJECTIVE: To observe the morphology and function changes of cochlear hair cells before and after math1 gene injection into the cochlea of deaf guinea pigs which were induced by kanamycin and furosemide. To explore the feasibility of Math1 gene for medicine-induced deafness therapy. METHODS: Kanamycin (500 mg/kg) and furosemide (50 mg/kg) were given to the healthy adult guinea pigs intramuscularly and intravenously to establish the deafness model. The guinea pigs whose auditory brainstem response (ABR) threshold > 95 dB SPL were randomly divided into five groups. Blank control group (without any treatment, n = 3), operation control group (right ear scala tympani operation, n = 3), artificial perilymph group (right ear scala tympani injection artificial perilymph, n = 3), virus vector group [right ear scala tympani injection adenovirus which carrying enhanced green fluorescent protein (EGFP) gene (Ad. EGFP) , n = 4], Math1 gene therapy group [right ear scala tympani injection adenovirus which carrying Math1 and EGFP gene (Ad. Math1-EGFP), n = 6]. Each animal received ABR test before and after injection. The cochlear tissue was observed by scanning electronic microscopy. RESULTS: The ABR thresholds of tone burst( 4, 8, 16, 20 kHz ) were not statistically significant in different groups (P > 0.05). The number of hair cells increased in some of severe deaf guinea pigs after the injection of Ad. Math1-EGFP gene. However, there was no obvious difference with morphology and numbers of cochlea hair cells in other groups. CONCLUSIONS: The injection of Math1 gene to cochlea can regenerate or repair the hair cells of medicine-induced deaf guinea pigs, but there was no improvement on the hearing loss.

[Surgical management and prognosis of iatrogenic peripheral facial nerve injury following middle ear surgery].

OBJECTIVE: To discuss the causes, sites, management strategies and curative effects of accidental facial nerve paralysis in the middle ear surgery. METHODS: Forty two cases with peripheral facial nerve paralysis following middle ear surgery who underwent surgical exploration and reanimation were analyzed. Facial nerve decompression, primary end-to-end anastomosis, interpositional nerve grafts with the great auricular nerve and nerve substitution of facial-hypoglossal anastomosis were applied to restoration of the facial nerve function. The facial nerve function was graded according to House-Brackmann (HB) Grade. RESULTS: The most common operation complicating iatrogenic facial nerve injury was mastoidectomy, and the common sites of the injured facial nerve were the tympanic segment and pyramid segment. The facial nerve exploration showed facial nerve edema in nine cases (21.4%), injury of the facial nerve sheath was observed in 10 cases (23.8%), partial nerve fibers transection was found in four cases (9.5%), total nerve fibers transection was detected in 17 cases (40.5%) and two cases (4.8%) with facial nerve anatomical integrity. Facial nerve re-animation methods include facial nerve decompression in 24 cases (57.1%), end-to-end anastomosis in two cases (4.8%), end-to-end anastomosis after nerve transfer in two cases (4.8%), interpositional nerve grafts with the great auricular nerve in 10 cases (23.8%) and facial-hypoglossal nerve anastomosis in four cases (9.5%). The facial nerve function was graded according to House-Brackmann Grade before and after surgery. Twenty eight patients were followed up more than one year. For the 17 cases who received facial nerve decompression, four cases recovered to House-Brackmann Grade I, 11 cases recovered to House-Brackmann Grade II, two cases recovered to House-Brackmann Grade III. For the five cases who underwent the great auricular nerve grafting, three cases recovered to House-Brackmann Grade II, two cases recovered to House-Brackmann Grade III. For the four cases who received facial-hypoglossal nerve anastomosis recovered to House-Brackmann Grade III. For the two cases who underwent the end-to-end anastomosis recovered to House-Brackmann Grade II. CONCLUSIONS: The tympanic segment and pyramid segment are more vulnerable to be injured during mastoid surgery. The injured facial nerve should be explored and repaired. The methods include facial nerve decompression, end-to-end anastomosis, end-to-end anastomosis after nerve transfer, interpositional nerve grafts with the great auricular nerve and facial-hypoglossal nerve anastomosis.