Naked Eye Research Articles

Colorimetric Detection of Sulfur Mustard with 4-(p-Nitrobenzyl)pyridine and Its Derivatives.

In this study, we present a simple, highly sensitive, and selective colorimetric method for detecting sulfur mustard (SM) and its simulants. This method relies on a nucleophilic substitution reaction between derivatives of 4-(p-nitrobenzyl)pyridine (NBP) and SM and subsequent treatment with an external base, resulting in a visible response. This reaction exhibits an impressively low detection threshold by the naked eye, as low as 10 ppm at room temperature. In contrast to the conventional use of NBP for detecting other alkylating agents, such as nitrogen mustard, our approach eliminates the need for prolonged heating or intricate extraction processes. Both computational and experimental investigations underscore the significance of water within our detection medium as it stabilizes crucial episulfonium cation intermediates. Furthermore, we demonstrate the practical applicability of this sensor by incorporating it onto cellulose and silica surfaces, which may provide guidance for the design and development of solid-state SM detectors.

Optimizing diagnosis and surgical decisions for chronic osteomyelitis through radiomics in the precision medicine era

Introduction: Chronic osteomyelitis is a complex clinical condition that is associated with a high recurrence rate. Traditional surgical interventions often face challenges in achieving a balance between thorough debridement and managing resultant bone defects. Radiomics is an emerging technique that extracts quantitative features from medical images to reveal pathological information imperceptible to the naked eye. This study aims to investigate the potential of radiomics in optimizing osteomyelitis diagnosis and surgical treatment.Methods: Magnetic resonance imaging (MRI) scans of 93 suspected osteomyelitis patients were analyzed. Radiomics features were extracted from the original lesion region of interest (ROI) and an expanded ROI delineated by enlarging the original by 5 mm. Feature selection was performed and support vector machine (SVM) models were developed using the two ROI datasets. To assess the diagnostic efficacy of the established models, we conducted receiver operating characteristic (ROC) curve analysis, employing histopathological results as the reference standard. The model’s performance was evaluated by calculating the area under the curve (AUC), sensitivity, specificity, and accuracy. Discrepancies in the ROC between the two models were evaluated using the DeLong method. All statistical analyses were carried out using Python, and a significance threshold of p < 0.05 was employed to determine statistical significance.Results and Discussion: A total of 1,037 radiomics features were extracted from each ROI. The expanded ROI model achieved significantly higher accuracy (0.894 vs. 0.821), sensitivity (0.947 vs. 0.857), specificity (0.842 vs. 0.785) and AUC (0.920 vs. 0.859) than the original ROI model. Key discriminative features included shape metrics and wavelet-filtered texture features. Radiomics analysis of MRI exhibits promising clinical translational potential in enhancing the diagnosis of chronic osteomyelitis by accurately delineating lesions and identifying surgical margins. The inclusion of an expanded ROI that encompasses perilesional tissue significantly improves diagnostic performance compared to solely focusing on the lesions. This study provides clinicians with a more precise and effective tool for diagnosis and surgical decision-making, ultimately leading to improved outcomes in this patient population.

Dose Optimization of Intravenous Indocyanine Green for Malignant Lung Tumor Localization

Background: Intravenously administered indocyanine green (ICG) accumulates in lung tumors, facilitating their detection via a fluorescence spectrum measurement. This method aids in identifying tumor locations that are invisible to the naked eye. We aim to determine the optimal ICG dose and administration method for accurate tumor identification during lung resection surgeries, utilizing a novel ICG fluorescence spectroscopy system for precise tumor localization. Materials and Methods: ICG should be dissolved in the provided solution or distilled water and administered intravenously approximately 24 h before surgery, beginning with an initial dose of 0.5 mg/kg. If the tumor detection rate is insufficient, the dose may be gradually increased to a maximum of 5.0 mg/kg to determine the optimal dosage for effective tumor detection. This fluorescence spectroscopy during surgery may reveal additional lesions that remain undetected in preoperative assessments. The primary endpoint includes the correct diagnostic rate of tumor localization. The secondary endpoints include the measurement of the intraoperative ICG fluorescence spectral intensity in lung tumors, the assessment of the operability and safety of intraperitoneal ICG administrations, the measurement of the ICG fluorescence spectral intensity in surgical specimens, the comparison of the spectral intensity in lung tissues during collapse and expansion, the correlation between ICG camera images and fluorescence spectral intensity, and the comparison of fluorescence analysis results with histopathological findings. The trial has been registered in the jRCT Clinical Trials Registry under the code jRCTs011230037. Results and Conclusions: This trial aims to establish an effective methodology for localizing and diagnosing malignant lung tumors, thereby potentially improving surgical outcomes and refining treatment protocols.

Facial Emotion Recognition using Convolutional Neural Network

Emotion is an expression that human use in expressing their feelings. It can be express through facial expression, body language and voice tone. Humans' facial expression is a major way in conveying emotion since it is the most powerful, natural and universal signal to express humans' emotion condition. However, humans' facial expression has similar patterns, and it is very confusing in recognizing the expression using naked eye. For instance, afraid and surprised is very similar to one another. Thus, this will lead to confusion in determining the facial expression. Hence, this study aims to develop a application for emotion recognition that can recognize emotion based on facial expression in real-time. The Deep Learning based technique, Convolutional Neural Network (CNN) is implemented in this study. The Mobile Net algorithm is deployed to train the model for recognition. There are four types of facial expressions to be recognized which are happy, sad, surprise, and disgusting. Keywords: Facial Emotion Recognition, Deep Learning, CNN, Image Processing.

Developing new Hydrazine Carbothioamide Molecules for Selective Colorimetric/Fluorometric Detection of Environmentally Essential Hg2+ and Ag+ Metal Ions in Mixed Aqueous Media

Developing new Hydrazine Carbothioamide Molecules for Selective Colorimetric/Fluorometric Detection of Environmentally Essential Hg2+ and Ag+ Metal Ions in Mixed Aqueous Media

Feasibility experiment of a novel deformable self-assembled magnetic anastomosis ring (DSAMAR) for gastrointestinal anastomosis through a natural orifice

Although the application of magnetic compression anastomosis is becoming increasingly widespread, the magnets used in earlier studies were mostly in the shape of a whole ring. Hence, a deformable self-assembled magnetic anastomosis ring (DSAMAR) was designed in this study for gastrointestinal anastomosis. Furthermore, its feasibility was studied using a beagle model. The designed DSAMAR comprised 10 trapezoidal magnetic units. Twelve beagles were used as animal models, and DSAMARs were inserted into the stomach and colon through the mouth and anus, respectively, via endoscopy to achieve gastrocolic magnamosis. Surgical time, number of failed deformations, survival rate of the animals, and the time of magnet discharge were documented. A month later, specimens of the anastomosis were obtained and observed with the naked eye as well as microscopically. In the gastrocolic anastomosis of the 12 beagles, the procedure took 65–120 min. Although a deformation failure occurred during the operation in one of the beagles, it was successful after repositioning. The anastomosis was formed after the magnet fell off 12–18 days after the operation. Naked eye and microscopic observations revealed that the anastomotic specimens obtained 1 month later were well-formed, smooth, and flat. DSAMAR is thus feasible for gastrointestinal anastomosis under full endoscopy via the natural orifice.

A Multimode Optical Sensor for Selective and Sensitive Detection of Harmful Heavy Metal Cr(VI) in Fresh Water and Sea Water.

Water pollution originating from heavy metals has shown great impacts on the ecological environment and human health due to their extremely low biodegradability. Hexavalent chromium Cr(VI), as one harmful heavy metal with strong oxidation, high biological permeability, and high carcinogenicity, is becoming an increasingly serious threat to human health. Therefore, conveniently but accurately, monitoring the Cr(VI) level in water to maintain its normal level and ensuring the stability of the ecosystem and human health become very valuable. However, most of these heavy metal sensors reported are turn-off type single-emission sensors. In this work, a ratiometric fluorescence/colorimetry/smartphone triple-mode turn-on optical sensor for Cr(VI) was developed based on a multifunctional metal-organic framework platform. The detection limits for these three mutual verification modes were only 1.28, 4.89, and 68.4 nM, respectively. Additionally, the color changes of the detection system under sunlight can also be observed directly by the naked eye. The accuracy and practicability of this multimode sensor were further proved by the detection of Cr(VI) in actual water and seawater samples, and the recovery rate ranged from 97.308 to 104.041%.

Bright Red Bioluminescence from Semisynthetic NanoLuc (sNLuc).

Red-shifted bioluminescence is highly desirable for diagnostic and imaging applications. Herein, we report a semisynthetic NanoLuc (sNLuc) based on complementation of a split NLuc (LgBiT) with a synthetic peptide (SmBiT) functionalized with a fluorophore for BRET emission. We observed exceptional BRET ratios with diverse fluorophores, notably in the red (I674/I450 > 14), with a brightness that is sufficient for naked eye detection in blood or through tissues. To exemplify its utility, LgBiT was fused to a miniprotein that binds HER2 (affibody, ZHER2), and the selective detection of HER2+ SK-BR-3 cells over HER2- HeLa cells was demonstrated.

MRI radiomics captures early treatment response in patient-derived organoid endometrial cancer mouse models

BackgroundRadiomics can capture microscale information in medical images beyond what is visible to the naked human eye. Using a clinically relevant mouse model for endometrial cancer, the objective of this study was to develop and validate a radiomic signature (RS) predicting response to standard chemotherapy.MethodsMice orthotopically implanted with a patient-derived grade 3 endometrioid endometrial cancer organoid model (O-PDX) were allocated to chemotherapy (combined paclitaxel/carboplatin, n=11) or saline/control (n=13). During tumor progression, the mice underwent weekly T2-weighted (T2w) magnetic resonance imaging (MRI). Segmentation of primary tumor volume (vMRI) allowed extraction of radiomic features from whole-volume tumor masks. A radiomic model for predicting treatment response was derived employing least absolute shrinkage and selection operator (LASSO) statistics at endpoint images in the orthotopic O-PDX (RS_O), and subsequently applied on the earlier study timepoints (RS_O at baseline, and week 1-3). For external validation, the radiomic model was tested in a separate T2w-MRI dataset on segmented whole-volume subcutaneous tumors (RS_S) from the same O-PDX model, imaged at three timepoints (baseline, day 3 and day 10/endpoint) after start of chemotherapy (n=8 tumors) or saline/control (n=8 tumors).ResultsThe RS_O yielded rapidly increasing area under the receiver operating characteristic (ROC) curves (AUCs) for predicting treatment response from baseline until endpoint; AUC=0.38 (baseline); 0.80 (week 1), 0.85 (week 2), 0.96 (week 3) and 1.0 (endpoint). In comparison, vMRI yielded AUCs of 0.37 (baseline); 0.69 (w1); 0.83 (week 2); 0.92 (week 3) and 0.97 (endpoint). When tested in the external validation dataset, RS_S yielded high accuracy for predicting treatment response at day10/endpoint (AUC=0.85) and tended to yield higher AUC than vMRI (AUC=0.78, p=0.18). Neither RS_S nor vMRI predicted response at day 3 in the external validation set (AUC=0.56 for both).ConclusionsWe have developed and validated a radiomic signature that was able to capture chemotherapeutic treatment response both in an O-PDX and in a subcutaneous endometrial cancer mouse model. This study supports the promising role of preclinical imaging including radiomic tumor profiling to assess early treatment response in endometrial cancer models.

Research status of colloidal gold detection technology in medicine

Research status of colloidal gold detection technology in medicine

Reproducibility of Naked Eye Single Tube Red cell Osmotic Fragility Test (NESTROFT) as a screening test for the detection of b thalassemia and Hemoglobin E traits with the variation of reading time

Background: Though 0.36% NaCl buffered solution has been used as an effective reagent for carrying out Naked Eye Single Tube Red cell Osmotic Fragility Test (NESTROFT) as a screening test for the detection of b thalassemia and Hemoglobin E traits, reading time for its interpretation is yet to be settled. Methods: This cross -sectional analytic study was done at Department of Pediatric Hematology and Oncology, BSMMU from January 2006-June 2007. NESTROFT was performed in 3 separate tubes for each of the 100 subjects (with â thalassemia trait and HbE trait and normal hemoglobin) with 0.36% NaCl buffered solution and reading was taken at different time at 5-minute, 15-minuteand 30-minute. Results were recorded as positive and negative. Hb electrophoresis, Hemogram with RBC indices for each sample and iron profile of selected subjects were done. Results: Among the 100 study subjects, 48 were carriers (18 were â thalassemia traits, 30 were Hb E traits). Age range was 1 to 52 yrs. Mean Hemoglobin concentration, MCV, MCH of both b thalassemia and Hb E carrier were significantly lower than normal subjects (p values <. 001). At 5-minute observation, NESTROFT was positive in 17 out of 18 â thalassemia traits with a sensitivity of 94.4%, 24 out of 30 HbE traits gave positive result with a sensitivity of 80%. Among the 52 normal subjects 35 gave negative result with a specificity of 67%. Positive predictive value and negative predictive value for detection of b thalassemia traits and HbE traits were 50% & 97% and 58% and 85%respectively. Result of NESTROFT interpreted at 15-minute and 30-minute did not show any change. Conclusion: From this study it may be concluded that for interpretation of NESTROFT reading at 5-minute would be optimum. BANGLADESH J CHILD HEALTH 2022; VOL 46 (3) : 130-137

Solid-Emission-Tunable Squaraine with Thermal-Promoted Aggregate-State Transitions for Fast Thermal History Sensing.

Determining thermal history is crucial in many industrial processes, but reliable and sensitive organic thermal history indicators are currently absent. Herein, we report on the development of a squaraine-based fluorescent molecule, DPEA-SQ, for the detection of thermal exposure histories up to 436 K. DPEA-SQ forms multiple single crystals (DPEA-SQ-I, DPEA-SQ-II, and DPEA-SQ-III) with different conformations and aggregate-state packing modes, contributing to their different fluorescence wavelengths, lifetimes, and efficiencies. Interestingly, DPEA-SQ-I and DPEA-SQ-III undergo aggregate-state structural transitions to form the thermodynamically more stable DPEA-SQ-II, which are accompanied by changes in their fluorescence. By taking advantage of similar aggregate-state structural transformations during heating, a high-temperature thermal exposure history of up to 436 K is recorded and reflected by their fluorescence. To demonstrate the potential practical applications of DPEA-SQ, a DPEA-SQ-Powder/PDMS film is prepared and coated on an electric circuit board, which enables real-time monitoring of localized overheating by the naked eye. Additionally, the fluorescence peaks of DPEA-SQ-Powder and DPEA-SQ-Powder/PDMS films remain unchanged after storage at 373 K for 52 days, demonstrating high aggregate-state stability. The fast and reliable responses of this system make it an excellent candidate for the detection of overtemperature traces in electronic components and circuit diagnosis.

A near-infrared fluorescent probe for the detection of Cu2+ in Chinese herbal medicine and imaging in living cells

Copper is one of the common among the heavy metal pollution in Chinese herbal medicine (CHM). So, it is essential to develop rapid and accurate testing method to quantify the Cu2+ content in CHM. Herein, we prepared a coordination-based near-infrared fluorescent probe (NRh6G-FA) by introducing a hemicyanine dye in rhodamine 6G scaffold. NRh6G-FA had a high sensitivity, anti-interference performance, fast response (within 60 s), visualization (from light yellow to green) for Cu2+ and excellent sensing performance for the detection of Cu2+ at low concentrations (LOD = 0.225 μM). The most likely mechanism was verified on the basis of Job’s plot, ESI-HRMS and DFT calculations. NRh6G-FA could be successfully applied for the detection and “naked eye” recognition of Cu2+ in CHM samples. Moreover, NRh6G-FA was used to visualize Cu2+ in living MCF-7 cells by confocal fluorescence imaging.

A new oligo(N,O-donor)-like ratiometric fluorescent probe with FRET effect for dual-channel recognition of B4O72- ions in practical water samples

B4O72- ions are widely found in various production and living environments, and can cause serious effects on human health. For this reason, it is necessary to develop a high-efficiency method for the detection of B4O72- ions. Here a oligo(N,O-donor)-like dual-channel ratiometric fluorescence probe H3L was designed and synthesized for the detection of B4O72- ions in environmental samples. The recognition of B4O72- is based on the FRET effect by the probe H3L, the naphthalene ring partially serves as an energy donor, benzene ring partially serves as an energy acceptor, and phenolic oxygen acts as a reaction site for B4O72-. The probe H3L mainly displays the blue fluorescence of the donor; the presence of the B4O72- ions turns on the FRET effect, which will lead to yellow fluorescence of the benzene ring acceptor, enabling a ratiometric fluorescence recognition process. The probe has a large Stokes red shift (Δλ = 123 nm), which makes the emission wavelength after red shift more than 500 nm, and the obvious colourless to yellow color change can be observed by naked eyes, which solves the background fluorescence interference problem of short-wavelength fluorescence probe. At the same time, the probe has high selectivity and high sensitivity (low detection limit of 17.3 nM). In addition, we have successfully used this probe to detect B4O72- ions in actual samples. These results showed that the probe has a broad application prospect.

Self-powered sandwich-type dual-mode sensor built on open bipolar electrode

Here, we developed a self-powered bipolar electrode (SP-BPE) based dual-mode sensor with electrochromic (EC) and photoelectrochemical (PEC) techniques for the visualized and sensitive detection of bisphenol A (BPA). An open BPE with the molecularly imprinted polymers (MIPs) modified electron injection area and the Prussian blue (PB) coated electrochromic area was fabricated on an indium tin oxide (ITO) glass. A kind of Zr-based metal-organic framework (UiO-66) coated TiO2 heterojunction (TiO2@UiO-66) was used for aptamer (Apt) immobilization and electron generation. BPA was selectively accumulated by MIPs, and subsequently recognized TiO2@UiO-66-Apt quantitatively, resulting in the formation of MIPs/BPA/Apt-TiO2@UiO-66 “sandwich” structure. Under UV-light, electrons were generated from the captured TiO2@UiO-66. For EC visualization measurements, electrons were injected into the PB film, causing a color change without an external power source. The extent of color change was proportional to the number of generated electrons, which correlated with the amount of captured BPA within a concentration range of 10−6–10−11 M. This allowed for the semi-quantification of BPA by naked eyes. For PEC detection, the BPE was used as the working electrode in a three-electrode system. The generated photocurrents signals could be digitally output for BPA with the concentrations ranging from 10−5 to 10−11 M. The SP-BPE sensors showed low background signal, improved selectivity and anti-interference abilities, and have demonstrated excellent performance in quantitative BPA analysis in water samples. They are particularly useful in scenarios where traditional power sources are limited or unavailable, and they offer opportunities for sustainable and environmentally friendly target detection.

Coumarinyl(pyrrolyl)ethenes for the detection of Pd2+, CN− and F− ions, test strips based on them and logic gates

New coumarinyl(pyrrolyl)ethenes with a 1,3-thiazole bridge were synthesized. When irradiated at 365 nm, a hexatriene-cyclohexadiene rearrangement of the ring-opened form into a colored non-fluorescent ring-closed isomer occurs. The back reaction takes place when exposed to visible light at 540 nm. Furthermore, the compound with terminal 2,4-di-tert-butyl-6-hydroxybenzylidene receptor group represents a multifunctional sensor exhibiting selective chromogenic activity towards palladium(II) ions and CN− and F− anions. This probe interacts with Pd2+ cations with a noticeable naked eye effect - a change in the solution color from yellow to orange. The complexation stoichiometry is 1:1 and the detection limit was found to be 4.5 × 10−7 mol L−1. Similarly, CN− and F− anions cause a contrast naked eye effect with a change in the color of the solution from yellow to rose-red. For convenient detection of the above ions, test strips containing 4-(2-(2-(2,4-di-tert-butyl-6-hydroxybenzylidene)hydrazinyl)-5-(2-oxo-2H-chromen-3-yl)thiazol-4-yl)-1,5-dimethyl-1H-pyrrole-2-carbonitrile have been developed. In addition, a combinatorial molecular logic gate was designed based on multi-controllable photoswitching properties of the obtained probe.

Plant diseases detection and classifications using SympDense- A fine-tuning deep learning model

A nation’s progress is directly linked to the effective functioning of its agricultural sector. The detection and classification of plant disease is an essential component of the agricultural industry. Plant diseases may result in substantial financial losses due to decreased crop production. As per the Food and Agriculture Organization of the United Nations, it is estimated that plant diseases result in a reduction of approximately 10-16% in global crop yields annually. Farmers are traditionally relying on visual inspection, using naked eye observation, as the primary method for detecting plant diseases. This involves a meticulous examination of crops to identify any visible signs of diseases. However, manual disease detection can lead to delayed identification, resulting in significant crop losses. Various methods, coupled with machine learning classifiers, were demonstrated effectiveness in scenarios involving manual feature extraction and limited datasets. However, to handle larger datasets, deep learning models such as Inception V4, ResNet-152, EfficientNet-B5, and DenseNet-201 were studied and implemented. Among these models, DenseNet-201 exhibited superior performance and accuracy compared to the previous methodology. Additionally, A Fine-tuning Deep Learning Model called SympDense was developed, which surpassed other deep learning models in terms of accuracy.

Pandemic Forms.

Narrative structures, though invisible to the naked eye, guide our understanding of pandemics. Like curves and graphs, we can plot them, identify their patterns and organizing principles. These structures act upon our understanding of social and biological events just as much as the rhythms of viral replication and mutation. They order not only themselves but also social and health outcomes. This essay uses narrative precision to expand beyond Charles Rosenberg's influential dramaturgic model and develops new pandemic forms, scaled from the level of an individual line break to the multi-part series: Arc, a form of sequence. Cycle, a form of repetition. Sequel, a form of elongation. Caesura, a form of break. It investigates the potentialities and limitations of these forms, how they intersect, collide, and contradict, and how analysis of these interactions contributes to a deeper understanding of pandemics, their effects, and the diverse perspectives defining their structures. In doing so, it prototypes how literary methods offer conceptual frameworks for pandemic historiography and how a transdisciplinary, medical humanities analysis produces novel understandings at the intersection of health, culture, and society.

A Fluorescent Probe for Hydrazine Based on 4-hydroxycoumarin with High Selectivity and Sensitivity

Background: Therefore, the development of reliable analytical techniques with high selectivity and sensitivity to detect hydrazine is required for the protection of human health and safety. Objectives: Traditional methods for detecting N2H4 are frequently time-consuming, less accurate, and unsuitable for the analysis of living systems. Numerous fluorescent probes for hydrazine have been produced and gained some valuable results recently. The creation of a simple fluorescent probe for hydrazine detection is the goal of this project Method: In this study, 300 µL of probe 3-methyl-2-oxo-2H-chromen-7-yl propionate (MOCP) was mixed with an equivalent amount of the solution of each analyte to obtain the measurement solution. Following a 10-minute room temperature incubation period, the fluorescence spectra of the resultant solution were recorded. Results: The fluorescence intensity of the probe was noticeably enhanced when N2H4 was added to the probe, but almost no fluorescence enhancement was observed when other competitive ions were added. Conclusion: A hydrazine fluorescent probe based on 4-hydroxycoumarin fluorophore was developed. The probe MOCP displayed high sensitivity and selectivity for hydrazine, with a color change from colourless to blue for detection by the naked eye. Moreover, it demonstrated a low detection limit of 20 nM and a fast reaction time of 30 s.

Porphyrin-based Schiff base fluorescent probe: Mercuric ion recognition by naked eye colorimetric analysis and application of test strip detection

(E)-4,4′,4″-(20-(4-(2-(2-hydroxybenzylidene)hydrazine-1-carbonyl)phenyl)porphyrin-5,10,15-triyl)tris(1-methylpyridin-1-ium) (named as Por-SA) was synthesized and developed as a fluorescent chemosensor for recognition towards Hg2+ ions in organic-semi aqueous DMSO(Dimethyl sulfoxide)/H2O (8:2, v/v) solution with high selectivity. The sensing ability of water-soluble Por-SA ligands to detect various cations was investigated in aqueous solutions via colorimetric and spectrophotometric methods. Hg2+ can be identified by naked eye colorimetric analysis, and the color of the solution changes from pink to green under daylight, the fluorescence of solution is significantly quenched under 365 nm UV lamp. The probe coordination mode to Hg2+ by probe was further evaluated by the means of density functional theory calculation (DFT), 1HNMR spectroscopy and Job's plot. Furthermore, the probe Por-SA can recognize Hg2+ with a low limit of detection of 17.3 μM. Probe Por-SA is successfully utilised for detecting the changes of Hg2+ ions in test paper strips. Therefore, Por-SA has the potential to become a universal tool for detecting target metal ions in the environmental and biological fields.