Paper-based colorimetric sensor using bimetallic Nickel-Cobalt selenides nanozyme with artificial neural network-assisted for detection of H2O2 on smartphone

Paper-based analytical devices (PADs) integrated with smartphones have shown great potential in various fields, but they also face challenges such as single signal reading, complex data processing and significant environmental impacting. In this study, a colorimetric PAD platform has been proposed using bimetallic nickel-cobalt selenides as highly active peroxidase mimic, smartphone with 3D-printing dark-cavity as a portable detector and an artificial neural network (ANN) model as multi-signal processing tool. Notably, the optimized nickel-cobalt selenides (Ni0.75Co0.25Se with Ni to Co ratio of 3/1) exhibit excellent peoxidase-mimetic activities and are capable of catalyzing the oxidation of four chromogenic reagents in the presence of H2O2. Using a smartphone with image capture function as a friendly signal readout tool, the Ni0.75Co0.25Se based four channel colorimetric sensing paper is used for multi-signal quantitative analysis of H2O2 by determining the Grey, red (R), green (G) and blue (B) channel values of the captured pictures. An intelligent on-site detection method for H2O2 has been constructed by combining an ANN model and a self-programmed easy-to-use smartphone APP with a dynamic range of 5 μM to 2 M. Noteworthy, machine learning-assisted smartphone sensing devices based on nanozyme and 3D printing technology provide new insights and universal strategies for visual ultrasensitive detection in a variety of fields, including environments monitoring, biomedical diagnosis and safety screening.

Engineering Platelet Membrane-Coated Bimetallic MOFs as Biodegradable Nanozymes for Efficient Antibacterial Therapy

Nanocatalytic-based wound therapeutics present a promising strategy for generating reactive oxygen species (ROS) to antipathogen to promote wound healing. However, the full clinical potential of these nanocatalysts is limited by their low reactivity, limited targeting ability, and poor biodegradability in the wound microenvironment. Herein, a bio-organic nanozyme is developed by encapsulating a FeZn-based bimetallic organic framework (MOF) (MIL-88B-Fe/Zn) in platelet membranes (PM@MIL-88B-Fe/Zn) for antimicrobial activity during wound healing. The introduction of Zn in MIL-88B-Fe/Zn modulates the electronic structure of Fe thus accelerating the catalytic kinetics of its peroxidase-like activity to catalytically generate powerful ROS. The platelet membrane coating of MOF innovatively enhanced the interaction between nanoparticles and the biological environment, further developing bacterial-targeted therapy with excellent antibacterial activity against both gram-positive and gram-negative bacteria. Furthermore, this nanozyme markedly suppressed the levels of inflammatory cytokines and promoted angiogenesis in vivo to effectively treat skin surface wounds and accelerate wound healing. PM@MIL-88B-Fe/Zn exhibited superior biodegradability, favourable metabolism and non-toxic accumulation, eliminating concerns regarding side effects from long-term exposure. The high catalytic reactivity, excellent targeting features, and biodegradability of these nanoenzymes developed in this study provide useful insights into the design and synthesis of nanocatalysts/nanozymes for practical biomedical applications.

Oxidase-like V2C MXene nanozyme with inherent antibacterial properties for colorimetric sensing

The microbial environment greatly affects the performance of colourimetric sensors, especially the interference of bacteria in the sample detected. This paper reports the fabrication of an antibacterial colorimetric sensor based on V₂C MXene synthesized via simple intercalation and stripping. The prepared V₂C nanosheets can mimic oxidase activity towards 3,3',5,5'-tetramethylbenzidine (TMB) oxidation without exogenously adding H₂O₂. Further mechanistic studies showed that V₂C nanosheets could effectively activate the oxygen adsorbed on their surface, which in turn causes an increase in the bond length and a decrease in the magnetic moment of oxygen through electron transfer from the nanosheet surface to O₂. The V₂C nanosheets also exhibited excellent broad-spectrum antibacterial activity through the outbreak of reactive oxygen species. Owing to its unique catalytic activity and the inherent antibacterial ability for mimicking oxidase, a colorimetric sensing platform was developed to effectively determine L-cysteine levels at a detection limit of 30.0 nM (S/N = 3). It is impressive that the detection results of L-cysteine in various complex microbial environments are also very satisfactory. This study broadens the biological use of MXene-based nanomaterials through their satisfactory enzymatic activity and provides a simple and efficient colorimetric strategy for detection techniques used in complex microbial environments.

[Clinical characteristics and prognosis in papillary thyroid carcinoma patients with recurrent laryngeal nerve invasion]

Objective: To investigate the clinical characteristics and risk factors of postoperative recurrence in papillary thyroid carcinoma (PTC) patients with recurrent laryngeal nerve (RLN) invasion. Methods: The data of PTC patients with recurrent laryngeal nerve invasion treated in Beijing Tongren Hospital, Capital Medical University from January 2006 to December 2019 were retrospectively analyzed. The acoustic parameters were compared between different subgroups. Kaplan-Meier method was used to calculate the overall survival (OS) and the recurrence-free rate (RFS), and univariate and multivariate Cox regression analyses were performed to determine the risk factors for postoperative recurrence. Results: A total of 150 PTC patients were enrolled in the final analysis, including 102 females and 48 males, with an average age of (53.5±13.7) years, and 62 patients (41.3%) aged over 55 years. There were 88 cases with stage Ⅰ, and 62 cases with stage Ⅲ. Fifty-five patients presented with preoperative vocal cord paralysis. There were 75 cases appearing adhesion between tumor or lymph node and recurrent laryngeal nerve while 75 cases presented with direct invasion. The comparisons of acoustic parameters showed that patients with RLN invasion had higher jitter compared with patients without RLN invasion [2.3% (1.4%, 3.2%) vs 1.8% (0.8%, 2.6%), P<0.001]. Moreover, patients with preoperative vocal cord paralysis (VCP) had higher jitter[3.1% (2.2%, 4.6%) vs 2.0% (1.1%, 2.8%), P<0.001] and shimmer [7.1% (4.9%, 9.9%) vs 5.5% (4.2%, 7.3%), P<0.001] and shorter maximum phonation time (MPT) [8.0 (6.0, 10.0) s vs 12.0 (10.0, 15.3) s, P<0.001] compared with patients without preoperative VCP. However, there was no statistical difference in acoustic parameters between cases with RLN adhesion and RLN invasion (all P>0.05). Postoperative follow-up time ranged between 12-196 months, with an average of (65.0±35.9) months. Sixteen patients (10.7%) had recurrence or metastasis, and 8 cases (5.3%) died of recurrence or metastasis. The 5-year OS rate was 95.1%, and the 10-year OS rate was 92.8%. The 5-year RFS rate was 88.9%, and the 10-year RFS rate was 86.2%. Univariate Cox analysis showed that age of onset ≥ 55 years, preoperative recurrent laryngeal nerve palsy, laryngeal, trachea or esophageal invasion were the risk factors for postoperative recurrence of PTC with RLN invasion (all P<0.05). Multivariate Cox analysis showed that age of onset ≥ 55 years (OR=1.060, 95%CI: 1.011-1.110, P=0.015) was an independent risk factor. Conclusions: Age of onset ≥ 55 years is an independent risk factor for postoperative recurrence in PTC patients with RLN invasion. Preoperative acoustic parameters may provide reference for evaluation of RLN function.

Cell Membrane and V2C MXene-Based Electrochemical Immunosensor with Enhanced Antifouling Capability for Detection of CD44

The inactive adsorption and interference of biomolecules in electrochemical biosensors is a topic of intense interest. Directly utilizing native cell membranes to endow electrochemical surfaces with antifouling and biocompatible features is a promising strategy, rather than attempting to synthetically replicate complex biological interface properties. In this study, we present a facial and sensitive sandwich-type antifouling immunoassay through platelet membrane/Au nanoparticle/delaminated V₂C nanosheet (PM/AuNPs/d-V₂C)-modified electrode as the substrate of sensing interface and methylene blue/aminated metal organic framework (MB@NH₂-Fe-MOF-Zn) as an electrochemical signal probe. The biosensor perfectly integrates the high conductivity of AuNPs-loaded V₂C MXene with the excellent loading property of NH₂-Fe-MOF-Zn to improve the electrochemical sensing performance. In addition, the excellent antifouling properties of the homogeneous cell membrane can effectively prevent the non-specific adsorption of model proteins. The obtained antifouling biosensor possesses the capability of ultrasensitive detection of CD44 and CD44-positive cancer cell in complex liquids and exhibits good analytical performance for the analysis of CD44 with a linear range from 0.5 ng/mL to 500 ng/mL. This strategy of developing cell membrane-based biosensing systems with enhanced antifouling capability can be easily expanded to the construction of other complex biosensors, and the advanced biological probes and analytical methods provide a favorable means to accurately quantify biomarkers associated with tumor progression.

Cell membrane-coated nanoparticles as peroxidase mimetics for cancer cell targeted detection and therapy

The development of novel and efficient recognition molecules that can be easily modified by nanomaterials to achieve ultra-sensitive and specific cancer cell analysis is of great significance for its early diagnosis and timely prognosis. Herin, a new nanostructured hybrid based on cell membrane-coated Au cores- ultrathin Pt skins composite nanoparticles (Au@Pt@CM NPs) were developed for in vitro detection and treatment of cancer cells. In this strategy, the Au@Pt NPs acted as the signal transducer, and the cell membrane were used as the cancer-cell recognition tool. The synthesized Au@Pt@CM NPs could catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of the hydrogen peroxide and were demonstrated to have excellent peroxidase-like activity. Coated with the source cancer cell membrane, the nanoparticles achieved highly specific self-recognition to the source cell. Therefore, the colorimetric method based on Au@Pt@CM NPs could detect the cancer cells in the linear range from 50 to 100000 cells/mL with a limit of detection of 5 cells/mL, which is much lower than other colorimetric detection methods. Afterwards, the nanoparticles as a mimetic enzyme were used for therapeutics of cancer cells through the ROS-mediated oxidative damage. Due to the change of the redox state in the cells by the Au@Pt@CM NPs, the hybrid can achieve the growth inhibitory effect and the selective killing effect on cancer cells. It can be expected that this novel hybrid membrane coating method will bring new insight into developing targeted nanomaterials for tumor treatment and detection.

Template-Regulated Bimetallic Sulfide Nanozymes with High Specificity and Activity for Visual Colorimetric Detection of Cellular H2O2

For the past several decades, most of the research studies on nanozymes have been aimed at improving their catalytic activity and diversity; however, developing nanozymes with strong catalytic activity and great specificity remains a challenge. Herein, a simple and efficient template synthesis method was used to synthesize bimetallic sulfide nanoparticles, NiCo₂S₄ NPs, and prove that they have excellent peroxidase-like activity with good specificity. By regulating polyvinyl pyrrolidone (PVP) and hexadecyl trimethyl ammonium bromide as the templating agent, we have obtained the NiCo₂S₄ (PVP) NPs with a high Ni/Co ratio, thus exhibiting superior peroxidase activity. In addition, the NiCo₂S₄ NPs selectively catalyzed and oxidized colorless 3,3,5,5-tetramethylbenzidine (TMB). On being treated with H₂O₂, TMB turns blue while other substrates did not undergo the oxidation reaction under the same conditions, such as 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium (ABTS) and dopamine. The high specificity of NiCo₂S₄ NPs is due to the strong electrostatic driving coordination between negatively charged NiCo₂S₄ NPs and positively charged TMB. Due to the peroxidase activity of the developed NiCo₂S₄ NPs, a simple, low-cost, and reliable colorimetric method was established. Simultaneously, this method for in situ quantitative monitoring of H₂O₂ produced by MDA-MB-231 cells was also achieved. This study has provided a theoretical basis for the improvement of the activity and specificity of bimetallic sulfide nanozymes and may offer guidance for the further reasonable design of related materials.

Single-particle fibrinogen detection using platelet membrane-coated fluorescent polystyrene nanoparticles

Fibrinogen participates in many physiological processes and is a biomarker for a variety of diseases. On this account, the development of a sensitive method for fibrinogen assay is particularly important. Herein, we demonstrate a new color-coded single-particle detection (SPD) method for fibrinogen detection by using platelet membrane-coated fluorescent polystyrene nanoparticles (PNPs) as the probes. Due to the specific interactions between fibrinogen and integrin receptors on platelet membranes, PNPs can form aggregated structures in the presence of fibrinogen. Therefore, colocalization events between green and red PNPs and the corresponding Pearson's correlation coefficient vary with the concentrations of fibrinogen. The sensing ability shows a linear range of 30-300 μg mL^-1 and a limit of detection (LOD) of 3.9 μg mL^-1 (11.3 nM) for fibrinogen detection. Moreover, it has been validated that the proposed biosensor can selectively detect fibrinogen and shows a good performance in real sample applications.

Excellent humidity sensor based on ultrathin HKUST-1 nanosheets

An excellent humidity sensor based on ultrathin HKUST-1 nanosheets was developed and some insights for the morphology–activity relationship were provided.

[A single-arm prospective study on induction chemotherapy and subsequent comprehensive therapy for advanced hypopharyngeal squamous cell carcinoma: report of 260 cases in a single center]

Objective: To study the significance of induction chemotherapy and subsequent comprehensive therapy for overall survival rate (OS) and larynx dysfunction-free survival rate (LDFS) in patients with advanced hypopharyngeal carcinoma. Methods: Patients who met the inclusion criteria with the diagnoses of advanced hypopharyngeal carcinoma between 2011 and 2017 received 2 or 3 cycles of TPF regimen induction chemotherapy. Patients who attained complete response (CR) received radical chemotherapy. Patients who attained partial response (PR) and the reduction of tumor volume was more than 70% were defined as large PR and received concurrent chemoradiotherapy. When the tumor volume reduction of PR patients was less than 70%, they were defined as small PR. (CR+large PR) group was defined as effective group. Patients who did not reach CR and large PR were defined as uneffective group and underwent radical surgery and received adjuvant radiotherapy as appropriate after the surgery. The end points of the study were OS, progression-free survival (PFS) and LDFS. Chi-square (χ(2)) test was used for correlation analysis. Survival analysis was performed by the Kaplan-Meier method with a Log-rank test. Cox proportional hazards model was used for univariate and multivariate survival analysis. Results: A total of 260 patients were enrolled in the study. The follow-up period ranged from 5 to 83 months, with an average of 24.7 months. The 3-year and 5-year OS rate was 46.0% and 32.6%, respectively. The 3-year and 5-year PFS rate was 41.0% and 26.6%, respectively. The 3-year and 5-year LDFS rate was 37.9% and 24.8%, respectively. Poor outcome of induction chemotherapy, advanced N stage, strong positive Ki-67 immunohistochemistry (all P<0.001) were negative prognostic factors. The advanced clinical stage was positively related to the poor outcome of induction chemotherapy (P=0.015). There was no significant difference in OS and PFS between the large PR group and the small PR group (all P>0.005). Conclusion: TPF regimen induction chemotherapy and subsequent comprehensive therapy for patients with advanced hypopharyngeal carcinoma may improve the quality of life of patients, with high OS rate and LDFS rate.

Dicer1 promotes Aβ clearance via blocking B2 RNA-mediated repression of apolipoprotein E

Metabolism of β-amyloid is critical for healthy brain. Decreased clearance of β-amyloid is associated with ensued accumulation of amyloid peptide, culminating in formation of senile plaques, a neuropathological hallmark of Alzheimer's disease(AD). Apolipoprotein E (APOE), a lipoprotein for phospholipid and cholesterol metabolism, is predominantly synthesized by glia in the central nervous system, controlling Aβ aggregation and metabolism. By use of stereotactic injection and a Morris water maze, we found that delivery of Dicer1-expressing adenovirus into the hippocampus of an animal model of AD mice APPswe/PSEN1deltaE9 significantly improved spatial memory. The effect was associated with reduced amyloid peptides in the hippocampus which were analyzed with immunofluorescence and enzyme-linked immunosorbent assay. With western blot, quantitative real-time PCR, fluorescence in situ hybridization, and northern blot,Dicer1 overexpression increased apolipoprotein E (APOE) and concomitantly decreased B2 RNA in the hippocampus of the AD mice and in astrocyte cultures whereas transfection of B2 Mm2 RNA decreased APOE mRNA and protein levels in astrocyte cultures. Further, human or mouse APOE mRNA was found containing Alu RNA or its equivalent, B2 Mm2 RNA, locating downstream of its 3'-untranslated region (UTR), respectively. The 3'-UTR or 3'-UTR in conjunction with the downstream Alu/B2 RNA were cloned into a luciferase reporter; with dual-luciferase assay, we found that simultaneous transfection of Dicer1 siRNA or Alu/B2 RNA decreased the corresponding luciferase activities which suggest that Alu RNA mediated APOE mRNA degradation. Altogether, Dicer1 expression mediated amyloid peptide clearance by increasing APOE via blocking B2 RNA-mediated APOE mRNA degradation.

[Analysis for potential targeting genes of TPF regimen induction chemotherapy in hypopharyngeal squamous cell carcinoma]

Objective: To analyze the differentially expressed genes related to the chemosensitivity with the TPF regimen for hypopharyngeal squamous cell carcinoma and to measure potential functional targeting genes expressions. Methods: Twenty-nine patients with primary hypopharyngeal cancer who underwent induction chemotherapy with TPF from January 2013 to December 2017 in Beijing Tongren Hospital were enrolled for microarray analysis, including 28 males and 1 female, aged from 43 to 73 years old. Among them, 16 patients were sensitive to chemotherapy while 13 patients were non-sensitive. Illumina Human HT-12 Bead Chip was applied to analyze the gene expressions and online bioinformatics analysis was used to analyze the differentially expressed genes. Reverse transcription and quantitative real-time PCR (RT-qPCR) was used to measure the mRNA expression of potential functional genes of TPF induction chemotherapy in 43 samples, 29 from original patients and 14 from additional patients. Graphpad prism 7.0 software was used for statistical analysis. Results: A total of 1 381 significantly differentially expressed genes were screened out. By GO analysis, up-regulated genes included sequestering in extracellular matrix, chemokine receptor binding and potassium channel regulator activity; down-regulated genes included regulation of angiogenesis, calcium ion binding and natural killer cell activation involved in immune response. With KEGG database analysis, down-regulated pathways included ECM-receptor interaction and peroxisome and up-regulated pathways included Glutathione metabolism and PPAR signaling pathway. The expressions of CD44 and IL-6R were significantly different and appeared biologically significant. CD44 was significantly upregulated in insensitive tissues (0.54±0.06) compared with sensitive tissues (0.33±0.04)(P<0.01). IL-6R was significantly downregulated in insensitive tissues (0.44±0.03) compared with sensitive tissues. (0.68±0.03) (P<0.01). Conclusion: CD44 and IL-6R may be potentially functional genes of TPF induction chemotherapy in hypopharyngeal squamous cell carcinoma.

Integrated analysis of different mRNA and miRNA profiles in human hypopharyngeal squamous cell carcinoma sensitive and resistant to chemotherapy

The purpose of this study was to identify potential miRNAs and mRNAs involved in chemotherapy insensitivity in hypopharyngeal squamous cell carcinoma (HSCC) and to explore the underlying mechanisms involved to provide diagnostic markers and therapeutic targets for HSCC. We used microarrays to identify differences in both the mRNA and miRNA expression profiles between a group (twelve patients) sensitive to chemotherapy and a resistant group (nine patients). We then employed bioinformatics tools to examine the functions and pathways involved. The genes and miRNAs most related to chemotherapy sensitivity in HSCC were screened. Finally, a miRNA-mRNA-phenotype network was constructed with an integrated analysis based on the identified miRNAs and mRNAs. Nine differentially expressed miRNAs and one hundred differentially expressed mRNAs were identified, and the functions of these genes and miRNAs were predicted. Bioinformatics analysis revealed a regulatory network consisting of eight genes and two miRNAs that influenced HSCC chemosensitivity. According to our analysis, CCL4L1 may be a potential molecular marker for HSCC chemotherapy, and excess CCL4L1 leads to the upregulation of PRAME and the downregulation of miR-375, thus decreasing HSPB8 expression and promoting chemotherapy sensitivity. Our work provides reliable data for further studies investigating the mechanism of HSCC chemotherapy sensitivity.

[Clinical observation of isolated immunoglobulin G4-related sclerosing cholangitis and immunoglobulin G4 sclerosing cholangitis combined autoimmune pancreatitis]

Objective: To compare and analyze patient's general condition, laboratory testing and therapeutic responses of isolated immunoglobulin G4- related sclerosing cholangitis (IgG4-SC) and immunoglobulin G4 sclerosing cholangitis combined autoimmune pancreatitis (IgG4-SC/AIP). Methods: A retrospective study was conducted on IgG4-SC patients who attended outpatient and inpatients department of our hospital from April 2014 to March 2018 and their demographic characteristics, laboratory testing, and therapeutic responses were statistically analyzed. Normal distribution of continuous variables was compared with t-test, non-normal distribution of continuous variables was compared using the Mann-Whitney U test, and the categorical variables were compared with χ (2) test. Results: 29 IgG4-SC patients were included, including 19-isolated IgG4-SC and 10 IgG4-SC combined AIP (IgG4-SC/AIP). The average age of onset in the isolated IgG4-SC group was (46.06±19.03) years which was lower than IgG4-SC/AIP group (62.60±15.11), t = -2.360, P < 0.05. The median IgG4 in IgG4-SC/AIP patients is higher than that in isolated IgG4-SC, respectively 10.87 (3.73 ~ 20.13) and 3.14 (2.37 ~ 4.78)g/L(U = 159.000, P < 0.05). IgG4/IgG ratio is higher in IgG4-SC/AIP, than that in isolated IgG4-SC, respectively 0.62(0.23 ~ 0.86) and 0.16(0.10 ~ 0.21), U = 130.000, P < 0.05. Liver cirrhosis was more common in isolated IgG4-SC group (47%) than the IgG4-SC/AIP group (0), χ (2) = 9.637, P < 0.05. The median biochemical response time of isolated IgG4-SC group was 3.00 (2.00 to 4.00) months, which was longer than 1.00 (1.00 to 1.25) months of IgG4-SC/AIP group, U = 30.000, P < 0.05. The biochemical recurrence rate of isolated IgG4-SC group was 32%, which was lower than that of IgG4-SC/AIP (χ (2) = 6.461, P < 0.05). Conclusion: Serum IgG4 level and IgG4/IgG ratio were higher in patients with IgG4-SC/AIP group, and therapeutic responses in isolated IgG4-SC patients were worse than that of IgG4-SC/AIP patients. The efficacy of glucocorticoid monotherapy and immunosuppressive agents combined with glucocorticoid therapy demonstrated no considerable difference in IgG4-SC patients.

[A preliminary analysis on potentially targeted genes of induced chemotherapy in supraglottic laryngeal squamous cell carcinoma]

OBJECTIVE

To analyze the differentially expressed genes produced by paclitaxel, cisplatin and 5-fluorouracil(TPF) regimen induction chemotherapy and the potentially functionally targeted genes of the induced chemotherapy in supraglottic laryngeal squamous cell carcinoma.

METHODS

A total of 11 tissue samples from patients diagnosed as supraglottic carcinoma who didn't receive any treatment before were analyzed with microarray. The patients were divided into two groups based on their responses to the induction chemotherapy: 7 were sensitive to chemotherapy and 4 were non-sensitive. Gene expressions were detected by Illumina Human HT-12 BeadChip. The bioinformatics analysis online was used to analyze the differentially expressed genes.

RESULTS

A total of 1 554 differentially expressed genes related to chemosensitivity were found. Analyzed with GO database, the up-regulated genes included the functional sets of biological adhesion, immune system development and stem cell proliferation, and the down-regulated genes included the functional sets of cell junction organization, phosphorus metabolic process and cell morphogenesis involved in differentiation. Analyzed with KEGG database, the up-regulated pathways included p53, cell adhesion and Ras signaling pathways, and the down-regulated pathways included focal adhesion, endocytosis and ErbB signaling pathways. There were statistically significant differences in the expressions of MAPK10, PIK3R5 and JUN genes, which had biological significance, between sensitive patients and non-sensitive patients.

CONCLUSION

MAPK10, PIK3R5 and JUN may be considered as potentially functional genes of the induced chemotherapy in supraglottic carcinoma.

[Establishment and characterization of a laryngeal squamous cell carcinoma cell line]

Objective: To establish a laryngeal squamous cell carcinoma (LSCC) cell line through primary cell culture and observe its biological characteristics. Methods: Tissue block culture method was used for primary cell culture. After LSCC cells passed 25 times in vitro, the morphology of cells was observed, keratin was stained histochemically, cell cycle was tested by PI-FACS, and the specie of cells was detected by PCR and short tandem repeat(STR) typing. Results: This newly established LSCC cell line was named as TR-LCC-1, most of the cancer cells were polygonal shape, like the cobblestone, loss of contact inhibition and with overlapping growth. Cell size was large and cell pleomorphism was very obvious. Cytokeratin staining was positive. After 6 months of continuous culture in vitro, the TR-LCC-1 cells passed more than 30 times, and cell doubling time was 201.2h. Cell cycle assay indicated that G1 phase accounted for 51.71%, S phase was 44.56%, and G2 phase was 2.28%. Mycoplasma test showed no mycoplasma contamination. Cell species identification identified TR-LCC-1 was human-derived cells. STR detection showed P26 and P6 were same, and they were different from the STR typing of disclosed cells. Conclusion: The establish ment of the new laryngeal squamous carcinoma cell line TR-LCC-1 can be helpful to the research for laryngeal squamous cell cancer.

Self-Assembled Peptide Hydrogel as a Smart Biointerface for Enzyme-Based Electrochemical Biosensing and Cell Monitoring

A self-assembled peptide nanofibrous hydrogel composed of N-fluorenylmethoxycarbonyl-diphenylalanine (Fmoc-FF) was used to construct a smart biointerface. This biointerface was then used for enzyme-based electrochemical biosensing and cell monitoring. The Fmoc-FF hydrogel had two functions. One was as a matrix to embed an enzyme model, horseradish peroxidase (HRP), during the self-assembly of Fmoc-FF peptides. The other was use as a robust substrate for cell adhesion. Experimental data demonstrated that HRP was immobilized in a stable manner within the peptide hydrogel, and that HRP retained its inherent bioactivity toward H2O2. The HRP also can realize direct electron transfer in the Fmoc-FF hydrogel. The resulting third-generation electrochemical H2O2 biosensor exhibited good analytical performance, including a low limit of detection of 18 nM, satisfactory reproducibility, and high stability and selectivity. HeLa cells were then adhered to the HRP/Fmoc-FF hydrogel-modified electrode. The sensitive in situ monitoring of H2O2 released from HeLa cells was realized. This biointerface based on the Fmoc-FF hydrogel was easily prepared, environmentally friendly, and also versatile for integration of other cells and recognized molecules for the monitoring of various cellular biomolecules. The smart biointerface has potential application in broad physiological and pathological investigations.

Emerging technologies to measure neighborhood conditions in public health: implications for interventions and next steps

Adverse neighborhood conditions play an important role beyond individual characteristics. There is increasing interest in identifying specific characteristics of the social and built environments adversely affecting health outcomes. Most research has assessed aspects of such exposures via self-reported instruments or census data. Potential threats in the local environment may be subject to short-term changes that can only be measured with more nimble technology. The advent of new technologies may offer new opportunities to obtain geospatial data about neighborhoods that may circumvent the limitations of traditional data sources. This overview describes the utility, validity and reliability of selected emerging technologies to measure neighborhood conditions for public health applications. It also describes next steps for future research and opportunities for interventions. The paper presents an overview of the literature on measurement of the built and social environment in public health (Google Street View, webcams, crowdsourcing, remote sensing, social media, unmanned aerial vehicles, and lifespace) and location-based interventions. Emerging technologies such as Google Street View, social media, drones, webcams, and crowdsourcing may serve as effective and inexpensive tools to measure the ever-changing environment. Georeferenced social media responses may help identify where to target intervention activities, but also to passively evaluate their effectiveness. Future studies should measure exposure across key time points during the life-course as part of the exposome paradigm and integrate various types of data sources to measure environmental contexts. By harnessing these technologies, public health research can not only monitor populations and the environment, but intervene using novel strategies to improve the public health.

Neighborhood Socioeconomic Deprivation and Geographic Heterogeneity of Tobacco Environment in Missouri

Purpose: To examine neighborhood characteristics associated with geographic distribution of tobacco sale outlets in Missouri. Methods: We obtained the addresses of tobacco outlets in Missouri from the Missouri Department of Mental Health. We geocoded these addresses and computed the outlet density by 5-digit ZIP codes. Using the data from the 2008–2012 American Community Survey, we developed a ZIP Code Tabulation Area (ZCTA)-level socioeconomic deprivation (SED) index. We analyzed the relationships of tobacco outlet density with neighborhood SED index and five separate socioeconomic indicators (%population with less than high school, %population unemployed, %households below the poverty, % population under the poverty, and %African Americans). Results: There were more than 5,000 tobacco retailers within Missouri in January, 2014. The number of tobacco retailers ranged from 0 to 56 (median = 2) per ZIP code, while tobacco outlet density ranged from 0 to 29 per 1,000 persons age 18+ (median: 1.18). Tobacco outlet density was significantly correlated with neighborhood SED (rho = 0.21, P &lt; 0.001). The consistency of quartiles of both variables was also statistically significant (weighted Kappa = 0.11, P &lt; 0.001). Logistic regression analysis indicated that neighborhood SED was associated with more than 3 times higher odds of denser tobacco outlets (&gt;median density) (the most vs. least deprived quartile: odd ratio = 3.24, 95% confidence interval = 2.26–4.65). Similar results were also found for each of the five individual socioeconomic indicators. Conclusion: Geographic distribution of tobacco retailing outlets was strongly associated with neighborhood SED environment. Neighborhoods with greater SED condition were also more likely to have a higher density of tobacco retailing outlets in Missouri. Our finding implies that higher accessibility to tobacco retailing outlets might play an important role in geographic SED disparity in smoking. Future studies should examine the degree to which neighborhood SED effect on smoking behaviors is mediated by higher accessibility to tobacco retailing outlets. This insight can help policy-makers develop appropriate geographic priority to effectively allocate tobacco control programs to reduce cigarette smoking in Missouri.

Hospital and geographic variability in two colorectal cancer surgery outcomes: complications and mortality after complications

BACKGROUND

The purpose of this study was to describe hospital and geographic variation in 30-day risk of surgical complications and death among colorectal cancer (CRC) patients and the extent to which patient-, hospital-, and census-tract-level characteristics increased risk of these outcomes.

METHODS

We included patients at least 66 years old with first primary stage I-III CRC from the 2000-2005 National Cancer Institute's Surveillance, Epidemiology, and End Results data linked with 1999-2005 Medicare claims. A multilevel, cross-classified logistic model was used to account for nesting of patients within hospitals and within residential census tracts. Outcomes were risk of complications and death after a complication within 30 days of surgery.

RESULTS

Data were analyzed for 35,946 patients undergoing surgery at 1,222 hospitals and residing in 12,187 census tracts; 27.2 % of patients developed complications, and of these 13.4 % died. Risk-adjusted variability in complications across hospitals and census tracts was similar. Variability in mortality was larger than variability in complications, across hospitals and across census tracts. Specific characteristics increased risk of complications (e.g., census-tract-poverty rate, emergency surgery, and being African-American). No hospital characteristics increased complication risk. Specific characteristics increased risk of death (e.g. census-tract-poverty rate, being diagnosed with colon (versus rectal) cancer, and emergency surgery), while hospitals with at least 500 beds showed reduced death risk.

CONCLUSIONS

Large, unexplained variations exist in mortality after surgical complications in CRC across hospitals and geographic areas. The potential exists for quality improvement efforts targeted at the hospital and/or census-tract levels to prevent complications and augment hospitals' ability to reduce mortality risk.

Are neighborhood conditions associated with HIV management?

OBJECTIVES

HIV infection has become a manageable chronic disease as a result of treatment advances. Secondary prevention efforts have proved inadequate to reduce the estimated incidence of new HIV infections. Epidemiological data suggest that geographical clustering of new HIV infections is a common phenomenon, particularly in urban areas among populations of low socioeconomic status. This study aimed to assess the relationship between neighbourhood conditions and HIV management and engagement in high-risk behaviours.

METHODS

During routine out-patient HIV clinic visits, 762 individuals from the St Louis metropolitan area completed behavioural assessments in 2008. Biomedical markers were abstracted from their medical records. Multi-level analyses were conducted based on individuals' census tracts.

RESULTS

The majority of the sample were male and African American. In the adjusted models, individuals residing in neighbourhoods with higher poverty rates were more likely to have lower CD4 cell counts and be current smokers. In neighbourhoods with higher rates of unemployment, individuals were less likely to have a current antiretroviral prescription. In more racially segregated neighbourhoods, individuals reported more depressive symptoms.

CONCLUSIONS

Despite the advances in HIV disease management, neighbourhood characteristics contribute to disparities in HIV care. Interventions that address neighbourhood conditions as barriers to HIV management may provide improved health outcomes.

AC electrothermal manipulation of conductive fluids and particles for lab-chip applications

AC electrokinetics has shown great potential for microfluidic functions such as pumping, mixing and concentrating particles. So far, electrokinetics are typically applied on fluids that are not too conductive (<0.02 S/m), which excludes most biofluidic applications. To solve this problem, this paper seeks to apply AC electrothermal (ACET) effect to manipulate conductive fluids and particles within. ACET generates temperature gradients in the fluids, and consequently induces space charges that move in electric fields and produce microflows. This paper reports two new ACET devices, a parallel plate particle trap and an asymmetric electrode micropump. Preliminary experiments were performed on fluids with conductivity at 0.224 S/m. Particle trapping and micropumping were demonstrated at low voltages, reaching approximately 100 microm/s for no more than 8 Vrms at 200 kHz. The fluid velocity was found to depend on the applied voltage as V(4), and the maxima were observed to be approximately 20 microm above the electrodes.

[A cross-sectional study on the effects of microcystin in drinking water to the health of human beings]

OBJECTIVE

To understand the effects of microcystin (MC) in drinking water on health of human beings.

METHODS

In Taixing, a cross-sectional study was conducted in two middle schools with different types of drinking water, from which 111 and 92 students were randomly selected and investigated. Blood samples from all individuals were collected and tested for serum HBsAg, HBeAg, anti-HBe, anti-HBs, anti-HBc with enzyme linked immunoabsorbent assay and for serum alanine aminotransferase (ALT), gamma-glutamyltransferase (gamma-GT) and alkaline phosphatase (ALP) contents by colorimetry. These levels of enzymes in sera were compared after the students were stratified according to the status of HBV infection.

RESULT

With the exclusion of the effect of HBV infection, three enzymes levels in sera between two groups of students showed significant differences (P < 0.01), much higher in exposure group than those in control group.

CONCLUSION

MC was possibly harmful to human beings in drinking water and induced the contents of some enzymes from the liver of human beings to increase in sera.

Factors affecting broadband ultrasound attenuation results of the calcaneus using a gel-coupled quantitative ultrasound scanning system

This study aimed to assess the factors that may influence the distribution and description of broadband ultrasound attenuation (BUA) and to identify specific criteria for diagnostic consideration when collecting BUA reference data. Two hundred Caucasian women (aged 20-79 years) without a history of atraumatic fractures or medicines known to affect bone metabolism were selected for this study. Medical and menstrual history, medication usage, family history of osteoporosis (FHO), physical activity, activities of daily living (ADL), dietary calcium intake, as well as smoking and alcohol consumption were obtained. Broadband ultrasound attenuation (BUA, dB/MHz) was determined in the right foot using a new gel-coupled ultrasound system. BUA was significantly associated with age (p<0.001), body weight (p<0.001), level of physical activity (p = 0.024) and dietary calcium intake (p = 0.023). Smoking, alcohol and coffee consumption and ADL were not associated with BUA (p>0.05). There were no differences in BUA (p>0.05) between those women who reported taking medications or had diseases (known to not affect bone metabolism), were using contraceptives, taking vitamin/mineral supplements and/or had traumatic fractures and their counterparts who did not report these characteristics. Premenopausal women with a FHO had significantly lower BUA values compared with those without a FHO (p = 0.013). When those participants with a FHO were removed from the sample, the peak BUA value was 1.1-4.4% higher and the variability (SD) was reduced by about 3.3-9.3% depending on which age range was used to define the peak BUA value. Consequently, an additional 4.5% of the population were classified as having a T-score <-2. Our results suggest that the impact on BUA of risk factors such as a FHO, body weight, physical activity and dietary calcium intake is similar to that on bone mineral density obtained by dual-energy X-ray absorptiometry (DXA), and thus provides further information on the comparability of quantitative ultrasound and DXA for assessment of risk of fracture. The criteria for calculating the T-score need further study to determine whether young adults with FHO should be included and what cutoff age range should be used in collecting peak values of quantitative ultrasound parameters.

The influence of stress on edentulous maxillary bone with different artificial anterior tooth arrangements by three-dimensional photoelasticity

OBJECTIVE

To investigate the influence of stress on edentulous maxillary bone different artificial anterior tooth arrangements, with the goal to establish theoretical evidence for optimal anterior tooth arrangements in complete denture restoration.

MATERIALS AND METHODS

Three-dimensional photoelasticity experimental stress analysis was conducted. Shear stresses were measured and principal stresses were separated into six different models of maxillary central incisor arrangements.

RESULTS

The value of maximum stresses and the absolute values of principal stresses and positive stresses were obtained. The distribution curve of shear stresses and principal stresses was also shown.

CONCLUSIONS

The horizontal distance between the incisive papilla center and the incisal margin of the maxillary central incisor should be no more than 8 mm, if the anterior mandibular arch is larger than the maxillary arch. The principal stress is a better indicator of stress on edentulous maxillary bone when load is applied at the protrusive occlusal position.

Effects of thrombolytic therapy on recanalization in different starting time of treatment after acute myocardial infarction

OBJECTIVE

To investigate the effects of thrombolytic therapy on recanalization in different starting time of treatment after acute myocardial infarction.

METHODS

172 cases with intravenous thrombolytic agents were divided into 4 groups: < or = 2 hours, > 2-4 hours, > 4-6 hours and > 6-12 hours, according to the different starting time of therapy after onset of symptoms.

RESULTS

The recanalization rates were 78.6%, 74%, 39. 6% and 14.3% in < or = 2 hours, > 2-4 hours, > 4-6 hours and > 6-12 hours, respectively. The recanalization rate within 4 hours was significantly higher than those in the groups of > 4-6 hours AND > 6-12 hours. The time interval from the initiation of thrombolytic therapy to reperfusion was increased as the starting time of thrombolysis after onset of symptoms was delayed.

CONCLUSIONS

Starting time of thrombolysis within 4 hours after onset of acute myocardial infarction is of the best effect on recanalization.