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We report a strategy for the camera-enabled non-contact colourimetric reaction monitoring and optimisation of amide bond formation, mediated by coupling reagents. For amide bond formation in solution phase, investigation of reactions mediated by HATU, PyAOP, and DIC/Oxyma evidenced correlations between colour parameters extracted from video data and conversion to amide product measured by off-line HPLC analysis of concentration. These correlations, supported by mutual information analysis, were further investigated using video recordings of solid phase peptide synthesis (SPPS), co-analysed by off-line HPLC to track remaining unreacted substrate in solution. An optimisation method of coupling time in SPPS was derived from ΔE (a measurement of colour contrast), giving comparable isolated peptide yield and purity at 65-95% reduced overall reaction time. The same colour data enabled data-rich monitoring of reaction rate attenuation, consisted with computationally-derived measures of amino acid steric bulk. These findings provide a foundation for exploring the use of camera technology and computer vision towards automated and online mechanistic profiling of SPPS.
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This Letter introduces sub-Nyquist sampling vertical scanning white light interferometry (SWLI) using deep learning. The method designs Envelope-Deep Residual Shrinkage Networks with channel-wise thresholds (E-DRSN-cw), a network model extracting oversampling envelopes from undersampled signals. The model improves the training efficiency, accuracy, and robustness by following the soft thresholding nonlinear layer approach, pre-padding undersampled interference signals with zeros, using LayerNorm for augmenting inputs and labels, and predicting regression envelopes. Simulation data train the network, and experiments demonstrate its superior performance over classical methods in the accuracy and the robustness. The E-DRSN-cw provides a swift measurement solution for SWLI, removing the need for prior knowledge.
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Presumptive (or 'spot') tests have served forensic scientists, law enforcement, and legal practitioners for over a hundred years. Yet, the intended design of such tests, enabling quick identification of drugs by-eye, also hides their full potential. Here, we report the development and application of time-resolved imaging methods of reactions attending spot tests for amphetamines, barbiturates, and benzodiazepines. Analysis of the reaction videos helps distinguish drugs within the same structural class that, by-eye, are judged to give the same qualitative spot test result. It is envisaged that application of these results will bridge the existing suite of field and lab-based confirmatory forensic tests, and support a broader range of colorimetric sensing technologies.
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We report a computer vision strategy for the extraction and colorimetric analysis of catalyst degradation and product-formation kinetics from video footage. The degradation of palladium(ii) pre-catalyst systems to form 'Pd black' is investigated as a widely relevant case study for catalysis and materials chemistries. Beyond the study of catalysts in isolation, investigation of Pd-catalyzed Miyaura borylation reactions revealed informative correlations between colour parameters (most notably ΔE, a colour-agnostic measure of contrast change) and the concentration of product measured by off-line analysis (NMR and LC-MS). The breakdown of such correlations helped inform conditions under which reaction vessels were compromised by air ingress. These findings present opportunities to expand the toolbox of non-invasive analytical techniques, operationally cheaper and simpler to implement than common spectroscopic methods. The approach introduces the capability of analyzing the macroscopic 'bulk' for the study of reaction kinetics in complex mixtures, in complement to the more common study of microscopic and molecular specifics.
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A software platform for the computer vision-enabled analysis of mixing phenomena of relevance to process scale-up is described. By bringing new and known time-resolved mixing metrics under one platform, hitherto unavailable comparisons of pixel-derived mixing metrics are exemplified across non-chemical and chemical processes. The analytical methods described are applicable using any camera and across an appreciable range of reactor scales, from development through to process scale-up. A case study in nucleophilic aromatic substitution run on a 5 L scale in a stirred tank reactor shows how camera and offline concentration analyses can be correlated. In some cases, it can be shown that camera data hold the power to predict reaction progress.
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Polarization remote sensing technology expands the dimensions of the target and enriches its basic information over traditional remote sensing methods. During the imaging process, polarization imaging changes the polarization information of the target by the modulation of the optical system, affecting the detection accuracy. We term the modulation of the polarization state of light by an optical system as polarization aberration, and we found that a lens group combined with mirrors is beneficial in suppressing polarization aberrations. This study analyzed the principles of suppression and the polarization aberration of the optical system before and after suppression. Simulation results show that the diattenuation's average value is reduced by 51.1% and the retardance's average value is reduced by 26.3% after suppression. The corrected polarization cross-coupled energy is reduced by 73.18% in the central field of view and by 69.80% in the fringe field of view. Adding a lens group also effectively suppresses traditional aberrations and expands the field of view.
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The dewatering performance of waste activated sludge (WAS) is generally deteriorated under low temperature due to the increase of viscosity, which would exacerbate the difficulties in sludge treatment and disposal. In this study, the cold-tolerant Bdellovibrio sp. CLL13 was successfully screened for efficient sludge biolysis, and it dramatically improved the sludge dewaterability while no significant biolysis effects were observed for the mesophilic BALO strain at 12 °C. The reduction rates of the sludge capillary suction time (CST), the specific resistance of filtration (SRF), the sludge dry weight, and the fecal coliform bacteria concentration at the optimal reaction time of 14 h were 40.1 ± 0.2%, 69.6 ± 0.7%, 7.7 ± 0.4%, and 78.5 ± 0.4%, respectively, when the mixed liquid suspended solids (MLSS) content was between 10.8 and 29.6 g/L, the input dosage of CLL13 was 8.8 × 106 PFU/mL sludge, and the DO level was 1.2 mg/L. Meanwhile, the viscosity reduction rate, the relative hydrophobicity increasement rate, and the bound water reduction rate were 20.3 ± 1.2%, 6.9 ± 0.7%, and 29.4 ± 1.0%, respectively. The ratios of protein content to polysaccharides content in the extracellular polymeric substances (EPS) decreased significantly. In addition, the degradation of the macromolecular substances in EPS and the increase of the soluble chemical oxygen demand, the total nitrogen, the total phosphorus, and the lactate dehydrogenase levels were observed. Therefore, the cold-tolerant CLL13 induced the sludge biolysis and compromised the negative effects of low temperature on the sludge dewatering performance, which should be beneficial for the efficient WAS biolysis treatment application in the near future under low temperature.
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Bdellovibrio , Aguas del Alcantarillado , Matriz Extracelular de Sustancias Poliméricas , Filtración , Aguas del Alcantarillado/química , Temperatura , Eliminación de Residuos Líquidos , Agua/químicaRESUMEN
Objective: Inflammation plays important role in atherosclerotic cardiovascular diseases (CVDs), but the interaction between the inflammation and lipid profile is largely unrevealed in humans. Patients with rheumatoid arthritis (RA) suffer from a higher risk of CVDs. Decreased total cholesterol (TC) and high-density lipoprotein (HDL) were prevalent in patients with RA. Anti-tumor necrosis factor (TNF) therapies relieve disease activity and decrease CVDs risk in RA, but their comprehensive effects on the lipid profile are unclear. This study aims to investigate the changes in blood lipid profile along time in the patients with RA accepting anti-TNF therapies by meta-analysis. Methods: The MEDLINE, the Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched for eligible literature. Data of lipids were classified into short-, mid-, and long-term according to treatment duration. Meta-analyses were performed to compare the lipid levels before and after treatments. Results: A total of 44 records and 3,935 patients were included in the meta-analyses. Anti-TNF therapies were associated with significant increase in TC [mean difference (MD): +0.14, +0.23, and +0.26 mmol/l, respectively] and HDL (MD): +0.11, +0.12, and +0.11 mmol/l, respectively) in the short-, mid-, and long-term; anti-TNF therapies were associated with increased low-density lipoprotein (LDL) (MD: +0.06 mmol/l) and apolipoprotein A1 (ApoA1) (MD: +0.07 g/l) in the short-term, but not in the mid-term and long-term; triglyceride (TG) and apolipoprotein B (ApoB) do not change significantly in all the periods; proatherosclerotic indexes (TC/HDL, ApoB/ApoA1, and LDL/HDL) tend to decrease in the short- and mid-term, but return to baseline in the long-term after TNF inhibition. Conclusion: Anti-TNF therapies were related to a long-term raised HDL level, which, together with evidence of improved HDL function, may contribute partially to the decreased CVDs risk by TNF inhibition.
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Trialkylammonium (most notably N,N,N-trimethylanilinium) salts are known to display dual reactivity through both the aryl group and the N-methyl groups. These salts have thus been widely applied in cross-coupling, aryl etherification, fluorine radiolabelling, phase-transfer catalysis, supramolecular recognition, polymer design, and (more recently) methylation. However, their application as electrophilic methylating reagents remains somewhat underexplored, and an understanding of their arylation versus methylation reactivities is lacking. This study presents a mechanistic degradation analysis of N,N,N-trimethylanilinium salts and highlights the implications for synthetic applications of this important class of salts. Kinetic degradation studies, in both solid and solution phases, have delivered insights into the physical and chemical parameters affecting anilinium salt stability. 1H NMR kinetic analysis of salt degradation has evidenced thermal degradation to methyl iodide and the parent aniline, consistent with a closed-shell SN2-centred degradative pathway, and methyl iodide being the key reactive species in applied methylation procedures. Furthermore, the effect of halide and non-nucleophilic counterions on salt degradation has been investigated, along with deuterium isotope and solvent effects. New mechanistic insights have enabled the investigation of the use of trimethylanilinium salts in O-methylation and in improved cross-coupling strategies. Finally, detailed computational studies have helped highlight limitations in the current state-of-the-art of solvation modelling of reaction in which the bulk medium undergoes experimentally observable changes over the reaction timecourse.
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PURPOSE: The long non-coding RNA cancer susceptibility 19 (CASC19) is recognized as an important regulator in gastric cancer, colorectal cancer, and non-small cell lung cancer. Nevertheless, to the best of our knowledge, the expression status and detailed roles of CASC19 in clear cell renal cell carcinoma (ccRCC) have not been elucidated. Hence, we aimed to determine CASC19 expression in ccRCC and investigate its roles in ccRCC oncogenicity. The molecular mechanisms underlying CASC19 functions in ccRCC were also determined. METHODS: CASC19 expression was measured by using reverse transcription-quantitative polymerase chain reaction. The effects of CASC19 on ccRCC cell proliferation, colony formation, migration, and invasiveness in vitro, as well as on tumor growth in vivo, were examined by the MTT assay, colony formation assay, cell migration and invasiveness assays, and tumor xenograft in nude nice, respectively. RESULTS: CASC19 was overexpressed in ccRCC tissues and cell lines. High expression of CASC19 was closely associated with unfavorable clinicopathological parameters and predicted negative clinical outcomes in patients with ccRCC. Knockdown of CASC19 decreased ccRCC cell proliferation, colony formation, migration, and invasiveness, as well as attenuated tumor growth in vivo. Mechanistically, CASC19 functioned as a competing endogenous RNA and upregulated the expression of ETS proto-oncogene 1 (ETS1) through sponging microRNA-532 (miR-532). Furthermore, rescue assays revealed that inhibiting miR-532 or restoring ETS1 expression partially abolished the impacts of CASC19 knockdown on ccRCC cells. CONCLUSION: The CASC19/miR-532/ETS1 regulatory pathway is crucial for the malignant manifestations of ccRCC, which makes it an attractive target for potential treatments of ccRCC.
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Single-pixel imaging techniques extend the time dimension to reconstruct a target scene in the spatial domain based on single-pixel detectors. Structured light illumination modulates the target scene by utilizing multi-pattern projection, and the reflected or transmitted light is measured by a single-pixel detector as total intensity. To reduce the imaging time and capture high-quality images with a single-pixel imaging technique, orthogonal patterns have been used instead of random patterns in recent years. The most representative among them are Hadamard patterns and Fourier sinusoidal patterns. Here, we present an alternative Fourier single-pixel imaging technique that can reconstruct high-quality images with an intensity correlation algorithm using acquired Fourier positive-negative images. We use the Fourier matrix to generate sinusoidal and phase-shifting sinusoid-modulated structural illumination patterns, which correspond to Fourier negative imaging and positive imaging, respectively. The proposed technique can obtain two centrosymmetric images in the intermediate imaging course. A high-quality image is reconstructed by applying intensity correlation to the negative and positive images for phase compensation. We performed simulations and experiments, which obtained high-quality images, demonstrating the feasibility of the methods. The proposed technique has the potential to image under sub-sampling conditions.
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A series of NHC-containing [C^N]- or [C^C']-type palladacyclic complexes of the general formula [PdBr(iPr2-bimy)(L^X)] (5-8, 11, 12, iPr2-bimy = 1,3-diisopropylbenzimidazolin-2-ylidene) have been synthesized and fully characterized. Using these complexes, the donating abilities of monoanionic chelators were probed for the first time. The [C^N]-type palladacycles 5-8 were prepared from acetato-bridged dipalladium complexes [Pd(µ-CH3COO)(C^N)]2 (1-4) and iPr2-bimy·H+Br-as precursors. In the case of the [C^C']-type NHC palladacycles (11, 12), the hetero-bis(NHC) complexes trans-[PdBr2(iPr2-bimy)(trz)] (8, 9, trz = 1,2,3-triazolin-5-ylidene) containing the iPr2-bimy probe were first prepared followed by acetate-assisted cyclopalladations. The 13Ccarbene NMR signals of the iPr2-bimy ligands in all complexes (i.e. HEP and HEP2 values) are found to rationally reflect the donating abilities of the incorporated trz or [L^X]-type chelators with the exception of the Bzpy ligand (Bzpy = 2-(2-pyridinylmethyl)phenyl-C,N). This has been attributed to its larger bite angle, the resulting varied coordination geometry and the lack of electronic delocalization between the two donor units. The donicities of [L^X]-type chelators studied in this work were found to surpass those of all other bidentate ligands evaluated by HEP2 thus far.
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Two coordination polymers with formula of [Tb(3-SBA) (IP)OH(H2O)] · H2O(1) and [Tb(dpdc)1.5 (IP) (H2O)]n (2) (3-SBA==3-sulfobenzoate, dpdc=2,2'-diphenyldicarboxylate and IP=1H-imidazo[4,5-f][1,10]-phenanthroline) have been synthesised under hydrothermal condition and characterizated by X-ray single crystal diffraction. The complex 1 possesses a 1D chain structure constructed from Tb(III) ions by 3-SBA ligands and OH groups. Complex 2 shows a 1D chain structure constructed from Tb(III) ions by dpdc ligands. The two complexes display the characteristic (5)D4-->7Fj (J=6-3) transitions at 492, 544,584 and 619 nm of Tb(III) ion, respectively. No emission from the ligand could be observed, which indicates that the ligands absorb and transfer energy efficiently to central Tb( M) ion. The emission decay curves reveal a monoexponential behaviour yielding the lifetime values of 0.287 ms for 1 and 0.439 ms for 2. The quantum yields of luminescence are 9.28% for 1 and 7.07% for 2.
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Entire C-genotype small hepatitis B surface (SHBs) sequences were isolated from 139 nucleos(t)ide analogues (NA)-naïve and 74 lamivudine (LMV)-treated chronic hepatitis B (CHB) patients. The conservation and variability of total 226 amino acids (AAs) within the sequences were determined individually, revealing significant higher mutant isolate rate and mutation frequency in LMV-treated cohort than those in the NA-naïve one (P=0.009 and 0.0001, respectively). Three absolutely conserved fragments (s16-s19, s176-s181 and s185-s188) and seven moderately conserved regions (a few AA sites acquiring increased variability after LMV-treatment) were identified. The significant mutation rate increase after LMV-treatment occurred primarily in major hydrophilic region (except 'a' determinant) and transmembrane domain 3/4, but not in other upstream functional regions of SHBs. With little influence on immune escape-associated mutation frequencies within 'a' determinant, LMV-monotherapy significantly induced classical LMVr-associated mirror changes sE164D/rtV173L, sI195M/rtM204V and sW196L/S/rtM204I, as well as non-classical ones sG44E/rtS53N, sT47K/A/rtH55R/Q and sW182stop/rtV191I outside 'a' determinant. Interestingly, another newly-identified truncation mutation sC69stop/rtS78T decreased from 7.91% (11/139) in NA-naïve cohort to 2.70% (2/74) in LMV-treated one. Altogether, the altered AA conservation and diversity in SHBs sequences after LMV-treatment in genotype-C HBV infection might shed new insights into how LMV-therapy affects the SHBs variant evolution and its antigenicity.
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Sustitución de Aminoácidos , Antivirales/uso terapéutico , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/tratamiento farmacológico , Lamivudine/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Codón sin Sentido , Femenino , Genotipo , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense , Adulto JovenRESUMEN
The present study was aimed to obtain baseline information of basal core promoter A1762T/G1764A and precore G1896A mutations of hepatitis B virus (HBV) in 192 HBeAg-positive chronically-infected Chinese patients, who were potential candidates for antiviral treatment. The detection of these mutations (including minor mutant subpopulations) was achieved by direct sequencing, whose sensitivity for minor mutant subpopulations identification was confirmed by clone sequencing. Patients enrolled were infected with either genotype B (46.35%) or C (53.65%) HBV identified by routine tests in our laboratory. The A1762T/G1764A or G1896A mutations were detected in 125specimens (125/192, 65.10%), in which 77 (77/125, 61.60%) existed as subpopulations. The A1762T/G1764A mutations were found to be more prevalent in genotype C than that in genotype B HBV [62.14% (64/103) vs. 20.22% (18/89), P<0.0001]. There is no statistically significant link between G1896A and genotypes. The emergence of A1762T/G1764A mutations was also found to be associated with an older age, an elevated ALT/AST level, and a lower HBsAg level in serum [wild-type vs. mutant: 4.57 (3.46-5.42) vs. 3.93 (2.51-5.36), P<0.0001]. In conclusion, HBV basal core promoter mutations A1762T/G1764A are associated with genotype C and a low serum HBsAg level in chronically-infected HBeAg-positive Chinese patients.
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Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Mutación Puntual , Regiones Promotoras Genéticas , Adulto , Factores de Edad , Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , China , ADN Viral/genética , Femenino , Genotipo , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/patogenicidad , Hepatitis B Crónica/patología , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
BACKGROUND: Antiviral drug-resistant HBV mutants under a variety of treatment protocols are complex and only partly understood. Here, a population-based cross-sectional study was performed to analyse the profile of resistance mutations in distinct evolutionary pathways refractory to different nucleoside/nucleotide analogues (NAs). METHODS: Serum samples of 199 chronic hepatitis B patients undergoing NA treatment from five hospitals in four northern cities of China were obtained between January 2007 and July 2009. The genotypic resistance of HBV in these samples was characterized. The full-length HBV reverse transcriptase region was amplified, sequenced and analysed with particular focus on the following NA-resistant changes: rtL80, rtI169, rtV173, rtL180, rtA181, rtT184, rtA194, rtS202, rtM204, rtN236 and rtM250. RESULTS: Among 199 HBV isolates, 30 (15.08%) and 169 (84.92%) were genotypes B and C, respectively, and 65 (32.66%) harboured NA-resistant mutations. The prevalence of mutations at rtM204 was 34.33% in 134 patients who had received or who had been exposed to lamivudine-based therapy. Five cases of rtN236 mutations were detected exclusively among 75 patients receiving adefovir-dipivoxil-based therapies. A total of 19 cases of multidrug resistance rtA181 mutations were observed in those with lamivudine-, adefovir-dipivoxil- or telbivudine-based treatment (186 cases), but not in those undergoing entecavir treatment (13 cases). Mutations were not found at rtI169, rtT184, rtA194 or rtS202. rtM204 mutations (27 rtM204I, 15 rtM204V and 5 rtM204I/V cases) were detected at the highest frequency among 65 mutants (72.30% [47/65]) and found to display 16 combination mutation patterns, in which rtM204I and rtM204V were significantly associated with rtL80I/V and rtL180M, respectively (P<0.01). CONCLUSIONS: One-third of the studied population harboured NA-resistant HBV with complicated mutation patterns. Monitoring HBV genotypic resistance mutation markers and patterns is therefore shown to be beneficial for optimizing antiviral therapies and for avoiding clinical deterioration.