Graphene, a truly two-dimensional (2D) and fully π-conjugated honeycomb network, exhibits many unique physical and chemical properties that are interesting in a wide range of areas. Since its ...discovery in 2004, graphene has been extensively studied in many different fields including nano-electronics, composite materials, energy research, catalysis and so on. Based on the fascinating action of members in the carbon family, notably zero dimensional (0D) fullerenes and one dimensional (1D) carbon nanotubes (CNTs) in biomedical areas, increasing number of reports have explored the potential of graphene for different biomedical and biotechnical applications since 2008. This manuscript aims to provide a summary of current research progress of graphene-based carbon materials in biosensing, drug (gene) delivery and tissue engineering, and discusses the opportunities and challenges in this rapidly growing field.
Summary Background Human infections with different avian influenza viruses—eg, H5N1, H9N2, and H7N9—have raised concerns about pandemic potential worldwide. We report the first human infection with a ...novel reassortant avian influenza A H10N8 virus. Methods We obtained and analysed clinical, epidemiological, and virological data from a patient from Nanchang City, China. Tracheal aspirate specimens were tested for influenza virus and other possible pathogens by RT-PCR, viral culture, and sequence analyses. A maximum likelihood phylogenetic tree was constructed. Findings A woman aged 73 years presented with fever and was admitted to hospital on Nov 30, 2013. She developed multiple organ failure and died 9 days after illness onset. A novel reassortant avian influenza A H10N8 virus was isolated from the tracheal aspirate specimen obtained from the patient 7 days after onset of illness. Sequence analyses revealed that all the genes of the virus were of avian origin, with six internal genes from avian influenza A H9N2 viruses. The aminoacid motif GlnSerGly at residues 226–228 of the haemagglutinin protein indicated avian-like receptor binding preference. A mixture of glutamic acid and lysine at residue 627 in PB2 protein—which is associated with mammalian adaptation—was detected in the original tracheal aspirate samples. The virus was sensitive to neuraminidase inhibitors. Sputum and blood cultures and deep sequencing analysis indicated no co-infection with bacteria or fungi. Epidemiological investigation established that the patient had visited a live poultry market 4 days before illness onset. Interpretation The novel reassortant H10N8 virus obtained is distinct from previously reported H10N8 viruses. The virus caused human infection and could have been associated with the death of a patient. Funding Emergency Research Project on human infection with avian influenza H7N9 virus, the National Basic Research Program of China, and the National Mega-projects for Infectious Diseases.
Supramolecular nanomedicines, which use supramolecular design to improve the precision and effectiveness of pharmaceutical practice and optimize pharmacokinetic profiles, have gathered momentum to ...battle cancer and other incurable diseases, for which traditional small‐molecular and macromolecular drugs are less effective. However, the lack of clinical approval of supramolecular assembly‐based medicine underscores the challenges facing this field. A 2D nanodisc‐based supramolecular structure is formed by a non‐ionic heptamethine cyanine (Cy7) dye, which generates fluorescence self‐quenching but unique photothermal and photoacoustic properties. These Cy7‐based supramolecular nanodiscs exhibit passive tumor‐targeting properties to not only visualize the tumor by near‐infrared fluorescence imaging and photoacoustic tomography but also induce photothermal tumor ablation under irradiation. Due to the nature of organic small molecule, they induce undetectable acute toxicity in mice and can be eliminated by the liver without extrahepatic metabolism. These findings suggest that the self‐assembling cyanine discs represent a new paradigm in drug delivery as single‐component supramolecular nanomedicines that are self‐delivering and self‐formulating, and provide a platform technology for synergistic clinical cancer imaging and therapy.
A two‐dimensional nanodisc‐based supramolecular structure is formed by using a nonionic heptamethine cyanine dye. The nanodiscs exhibit unique photothermal and photoacoustic properties to make imaging‐guided tumor therapy a reality. This strategy represents a new paradigm in drug delivery; single‐component supramolecular nanomedicines that are self‐delivering and self‐formulating, providing a technology platform for synergistic clinical cancer imaging and therapy.
This study focuses on the comparison of hybrid methods of estimation of biophysical variables such as leaf area index (LAI), leaf chlorophyll content (LCC), fraction of absorbed photosynthetically ...active radiation (FAPAR), fraction of vegetation cover (FVC), and canopy chlorophyll content (CCC) from Sentinel-2 satellite data. Different machine learning algorithms were trained with simulated spectra generated by the physically-based radiative transfer model PROSAIL and subsequently applied to Sentinel-2 reflectance spectra. The algorithms were assessed against a standard operational approach, i.e., the European Space Agency (ESA) Sentinel Application Platform (SNAP) toolbox, based on neural networks. Since kernel-based algorithms have a heavy computational cost when trained with large datasets, an active learning (AL) strategy was explored to try to alleviate this issue. Validation was carried out using ground data from two study sites: one in Shunyi (China) and the other in Maccarese (Italy). In general, the performance of the algorithms was consistent for the two study sites, though a different level of accuracy was found between the two sites, possibly due to slightly different ground sampling protocols and the range and variability of the values of the biophysical variables in the two ground datasets. For LAI estimation, the best ground validation results were obtained for both sites using least squares linear regression (LSLR) and partial least squares regression, with the best performances values of R2 of 0.78, rott mean squared error (RMSE) of 0.68 m2 m−2 and a relative RMSE (RRMSE) of 19.48% obtained in the Maccarese site with LSLR. The best results for LCC were obtained using Random Forest Tree Bagger (RFTB) and Bagging Trees (BagT) with the best performances obtained in Maccarese using RFTB (R2 = 0.26, RMSE = 8.88 μg cm−2, RRMSE = 17.43%). Gaussian Process Regression (GPR) was the best algorithm for all variables only in the cross-validation phase, but not in the ground validation, where it ranked as the best only for FVC in Maccarese (R2 = 0.90, RMSE = 0.08, RRMSE = 9.86%). It was found that the AL strategy was more efficient than the random selection of samples for training the GPR algorithm.
Mg alloys offer potential advantages over conventional biomedical implant materials because of their biodegradability and biocompatibility, but could be limited by their poor mechanical properties. ...In this study, laser shock peening (LSP), a surface processing technique, was applied to improve the mechanical properties of the AZ31B magnesium (Mg) alloy. It was demonstrated that LSP increased the hardness and yield strength of the Mg alloy. Due to the hardening, LSP significantly improved the wear resistance and fatigue performance of the Mg alloy. In addition, immersion tests carried out in cell culture medium revealed that LSP did not significantly increase Mg2+ release and weight loss. Furthermore, an in vitro cell culture study showed that the LSP-treated samples have cell-compatibility comparable to untreated samples. Thus, the LSP technique could, with further study, advance the clinical utility of Mg alloys in the orthopedic field.
•LSP significantly decreased the coefficient of friction and improved the wear resistance of AZ31B alloy.•LSP significantly improved the tensile strength and fatigue resistance of AZ31B alloy.•LSP-treated samples have cell-compatibility comparable to untreated samples.
Blocking vascular endothelial growth factor pathway can enhance the efficacy of EGFR tyrosine kinase inhibitors in EGFR-mutant NSCLC. ACTIVE is the first phase 3 study conducted in the People’s ...Republic of China evaluating apatinib, a vascular endothelial growth factor receptor 2 tyrosine kinase inhibitor, plus gefitinib as first-line therapy in EGFR-mutant NSCLC.
Treatment-naive patients with stage IIIB or IV nonsquamous NSCLC, an Eastern Cooperative Oncology Group performance status of 0 or 1, and EGFR exon 19 deletion or exon 21 L858R mutation were randomized 1:1 to receive oral gefitinib (250 mg/d), plus apatinib (500 mg/d; apatinib A + gefitinib G group), or placebo (placebo P + gefitinib G group). Stratification factors were mutation type, sex, and performance status. The primary end point was progression-free survival (PFS) by blinded independent radiology review committee (IRRC). Secondary end points were investigator-assessed PFS, overall survival, quality of life (QoL), safety, etc. Next-generation sequencing was used to explore efficacy predictors and acquired resistance.
A total of 313 patients were assigned to the A + G (n = 157) or P + G group (n = 156). Median IRRC PFS in the A + G group was 13.7 months versus 10.2 months in the P + G group (hazard ratio 0.71, p = 0.0189). Investigator- and IRRC-assessed PFS were similar. Overall survival was immature. The most common treatment-emergent adverse events greater than or equal to grade 3 were hypertension (46.5%) and proteinuria (17.8%) in the A + G group and increased alanine aminotransferase (10.4%) and aspartate aminotransferase (3.2%) in the P + G group. QoL in the two groups had no statistical differences. Post hoc analysis revealed PFS benefits tended to favor the A + G group in patients with TP53 exon 8 mutation.
Apatinib + gefitinib as first-line therapy had superior PFS in advanced EGFR-mutant NSCLC versus placebo + gefitinib. Combination therapy brought more adverse events but did not interfere QoL.
NCT02824458.
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•We incorporate the methine groups of heptamethine cyanines into the cyclic frame to construct a new near-infrared (NIR) molecular rotor Mu1.•Mu1 is superior to the traditional ...cyanines with high viscosity response, large stokes shift (˜100 nm), high photo-stability and selectivity.•Mu1 can ratiometrically track mitochondrial viscosity changes in live cells with high spatial and temporal resolution.
We developed a new cyanine-derived near-infrared (NIR) molecular rotor Mu1, which is superior to the traditional cyanines with high viscosity response, large Stokes shift (˜100 nm), and high photo-stability to detect the microscopic viscosity ratiometrically. The time-dependent density functional theory calculations highlighted the structure-optical properties of Mu1 as molecular rotor. Due to the mitochondria-actived fluorescence characteristics, Mu1 was used to track mitochondrial viscosity changes in live cells with high spatial and temporal resolution. This new type of NIR molecular rotor presented herein may open up new opportunities of NIR sensors for biomedical diagnosis and imaging applications.
Leaf chlorophyll content (LCC) provides valuable information about the nutrition and photosynthesis statuses of crops. Vegetation index-based methods have been widely used in crop management studies ...for the non-destructive estimation of LCC using remote sensing technology. However, many published vegetation indices are sensitive to crop canopy structure, especially the leaf area index (LAI), when crop canopy spectra are used. Herein, to address this issue, we propose four new spectral indices (The red-edge-chlorophyll absorption index (RECAI), the red-edge-chlorophyll absorption index/optimized soil-adjusted vegetation index (RECAI/OSAVI), the red-edge-chlorophyll absorption index/ the triangular vegetation index (RECAI/TVI), and the red-edge-chlorophyll absorption index/the modified triangular vegetation index(RECAI/MTVI2)) and evaluate their performance for LCC retrieval by comparing their results with those of eight published spectral indices that are commonly used to estimate LCC. A total of 456 winter wheat canopy spectral data corresponding to physiological parameters in a wide range of species, growth stages, stress treatments, and growing seasons were collected. Five regression models (linear, power, exponential, polynomial, and logarithmic) were built to estimate LCC in this study. The results indicated that the newly proposed integrated RECAI/TVI exhibited the highest LCC predictive accuracy among all indices, where R2 values increased by more than 13.09% and RMSE values reduced by more than 6.22%. While this index exhibited the best association with LCC (0.708** ≤ r ≤ 0.819**) among all indices, RECAI/TVI exhibited no significant relationship with LAI (0.029 ≤ r ≤ 0.167), making it largely insensitive to LAI changes. In terms of the effects of different field management measures, the LCC predictive accuracy by RECAI/TVI can be influenced by erective winter wheat varieties, low N fertilizer application density, no water application, and early sowing dates. In general, the newly developed integrated RECAI/TVI was sensitive to winter wheat LCC with a reduction in the influence of LAI. This index has strong potential for monitoring winter wheat nitrogen status and precision nitrogen management. However, further studies are required to test this index with more diverse datasets and different crops.
The identification of the first human polyomavirus BK (BKV) has been over half century, The previous epidemiological and phylogenetic studies suggest that BKV prevailed and co-evolved with humans, ...leading to high seroprevalence all over the world. In general, BKV stays latent and symptomless reactivation in healthy individuals. BKV has been mainly interlinked with BKV-associated nephropathy (BKVAN) in kidney-transplant recipients and hemorrhagic cystitis (HC) in hematopoietic stem cell transplant recipients (HSCTRs). However, the mechanisms underlying BKV latency and reactivation are not fully understood and lack of extensive debate. As Merkel cell polyomavirus (MCV) was identified as a pathogenic agent of malignant cutaneous cancer Merkel cell carcinoma (MCC) since 2008, linking BKV to tumorigenesis of urologic tumors raised concerns in the scientific community. In this review, we mainly focus on advances of mechanisms of BKV latency and reactivation, and BKV-associated diseases or tumorigenesis with systematical review of formerly published papers following the PRISMA guidelines. The potential tumorigenesis of BKV in two major types of cancers, head and neck cancer and urologic cancer, was systematically updated and discussed in depth. Besides, BKV may also play an infectious role contributing to HIV-associated salivary gland disease (HIVSGD) presentation. As more evidence indicates the key role of BKV in potential tumorigenesis, it is important to pay more attention on its etiology and pathogenicity
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China is one of the countries with the richest snake biodiversity in the world. However, about one‐third of all 236 species are now considered threatened, partially due to the intense human ...overexploitation. Despite that, to date, no study has explicitly investigated the patterns and processes of extinction and threats of Chinese snakes, or between human exploited and unexploited snake subgroups. We addressed the following three questions: 1) which snake families proportionally include more human exploited species than expected by chance? 2) Which species traits and extrinsic factors are correlated with their extinction risk? 3) Are there differences between human exploited and unexploited species in terms of patterns and processes of extinction? We found that the family Elapidae contained a significantly higher number of exploited species. Considering eight species traits and four extrinsic factors, we performed phylogenetic correlation tests, finding that small geographic range size, large body length, oviparous reproduction, diurnal activity and high human exploitation were important in determining the extinction risk of all Chinese snakes. Moreover, human exploited snakes had a higher percentage of threatened species and large‐bodied species than unexploited snakes. Extinction risk of human exploited species was related to body length, reproduction mode and activity period, whereas that of human unexploited species were associated with geographic range size, microhabitat and annual temperature. Overall, we highlight the phylogenetic non‐random exploitation of snakes, and different factors underlying species response to human overexploitation. We suggest that conservation priority should be given to exploitation‐prone families and species with extinction‐prone traits, as identified in this study. Moreover, human exploited and unexploited species should be managed considering different strategies since their extinction risk was associated with different ecological traits. Conservation actions should also focus on preventing human threats, such as human overexploitation and habitat loss, for the effective preservation of Chinese snakes.
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