Detection of Cadmium in Human Biospecimens by a Cadmium-Selective Whole-Cell Biosensor Based on Deoxyviolacein.

Cadmium poses a severe health risk, impacting various bodily systems. Monitoring human exposure is vital. Urine and blood cadmium serve as critical biomarkers. However, current urine and blood cadmium detection methods are expensive and complex. Being cost-effective, user-friendly, and efficient, visual biosensing offers a promising complement to existing techniques. Therefore, we constructed a cadmium whole-cell biosensor using CadR10 and deoxyviolacein pigment in this study. We assessed the sensor for time-dose response, specific response to cadmium, sensitivity response to cadmium, and stability response to cadmium. The results showed that (1) the sensor had a preferred signal-to-noise ratio when the incubation time was 4 h; (2) the sensor showed excellent specificity for cadmium compared to the group 12 metals and lead; (3) the sensor was responsive to cadmium down to 1.53 nM under experimental conditions and had good linearity over a wide range from 1.53 nM to 100 µM with good linearity (R2 = 0.979); and (4) the sensor had good stability. Based on the excellent results of the performance tests, we developed a cost-effective, high-throughput method for detecting urinary and blood cadmium. Specifically, this was realized by adding the blood or urine samples into the culture system in a particular proportion. Then, the whole-cell biosensor was subjected to culture, n-butanol extraction, and microplate reading. The results showed that (1) at 20% urine addition ratio, the sensor had an excellent curvilinear relationship (R2 = 0.986) in the range of 3.05 nM to 100 µM, and the detection limit could reach 3.05 nM. (2) At a 10% blood addition ratio, the sensor had an excellent nonlinear relationship (R2 = 0.978) in the range of 0.097-50 µM, and the detection limit reached 0.195 µM. Overall, we developed a sensitive and wide-range method based on a whole-cell biosensor for the detection of cadmium in blood and urine, which has the advantages of being cost-effective, ease of operation, fast response, and low dependence on instrumentation and has the potential to be applied in the monitoring of cadmium exposure in humans as a complementary to the mainstream detection techniques.

Single-cell and whole-transcriptome sequencing of lymph node metastasis-related gene signature: A large-scale pan-cancer cohort, machine learning and experimental study.

BACKGROUND: Lymph node metastasis (LNM) is an independent prognostic factor in numerous types of cancer. Therefore, a LNM-related gene-based nomogram may precisely predict survival and drug sensitivity, and reveal the mechanism underlying LNM. MATERIALS AND METHODS: Gene sequencing profiles of pan-cancer data (33 cancer types) were acquired from The Cancer Genome Atlas UCSC Xena database. Patients were classified into primary (N = 10,071) and testing (N = 5,036) cohorts. The lymph node score (LNscore) was established via single-cell RNA sequencing, whole-transcriptome sequencing, machine learning, and Cox regression analyses. A novel prognosis model, formulated by incorporating the LNscore and clinical characteristics, was evaluated using the concordance index, calibration curve, and decision curve analysis. Moreover, patients were assigned into high- and low-risk groups according to the median LNscore. We investigated these two groups for survival prognosis, functional enrichment, immune infiltration, and drug sensitivity. In addition, we silenced and overexpressed insulin like growth factor 2 mRNA binding protein 2 (IGF2BP2). We also analyzed the behavior of breast cancer (BRCA) cells regarding lymphatic metastasis and lymphangiogenesis in vitro. IGF2BP2 stimulated the proliferation of BRCA cells via 5-Ethynyl-2'-deoxyuridine and Cell Counting Kit-8 experiments. RESULTS: A LNM-related set of 12 genes was identified and utilized to determine the LNscore. The concordance-index of both cohorts in the LNscore-based model was >0.7. The immune landscape revealed that the sensitivity to immunotherapy might be better in the high-risk group versus the low-risk group. In addition, we discovered that IGF2BP2 was overexpressed in BRCA tissues and significantly associated with poor survival. Functional analysis indicated that IGF2BP2 promoted BRCA cell migration and proliferation. Additionally, IGF2BP2 accelerated lymphatic metastasis and lymphangiogenesis in vivo. CONCLUSIONS: A novel LNscore-based model was established via comprehensive analysis of LNM-related genes. This model can accurately predict patient survival and drug sensitivity, and reveal the mechanism of LNM in the pan-cancer setting.

Orthokeratology combined with spectacles in moderate to high myopia adolescents.

PURPOSE: Wearing ortho-k lenses overnight may not fully correct their daytime refractory errors of adolescents with moderate to high myopia. There are three common ways to deal with the daytime residual refractive error (RRE): 1) wearing spectacles to correct the RRE; 2) wear ortho-k lenses during the daytime instead of overnight.; 3) not correcting the residual refractive error. According to previous laboratory studies, myopic peripheral refraction is associated with better myopic control. This study had two aims:1) to compare relative peripheral refractive error (RPRE) among these ways after one-month stabilization; 2) to assess the axial length changes over 2 years of ortho-k lens overnight wear combined with spectacle glasses. METHODS: This was a prospective, non-controlled, non-randomized, observational study in which a total of 27 subjects (20 females, 7 males, mean age 12.48 ± 2.23Y) with spherical equivalent refractive error from -5.00 to -8.25D were enrolled. All participants in the study wore orthokeratology (ortho-k) lenses overnight for a minimum of one month. Subsequently, their peripheral refractive error (PRE) was assessed using an open-field autorefractor. During the assessment, the participants underwent three conditions in a random order in a same morning: 1) unaided eye after orthokeratology (referred to as the Unaided-eye condition), 2) wearing glasses to correct any remaining refractive errors after orthokeratology (referred to as the Spec-RE condition), and 3) wearing ortho-k lenses during the daytime (referred to as the Continuous OK wear condition). After testing, all subjects were instructed to wear ortho-k lenses overnight and glasses during the daytime to correct their RRE for the next 2 years, during which time the progression of their axial length was followed up. RESULTS: 1) RPRE in either Unaided-eye or Spec-RE condition subjects were significantly more myopic than those in the Continuous OK wear condition. 2) No difference in RPRE was seen between Unaided-eye and Spec-RE conditions. 3) Axial length growth was 0.05 ± 0.20 mm and 0.17 ± 0.32 mm (mean ± standard deviation) at 1-year and 2-year follow-ups after the initial visit, respectively, which were comparable to mild myopia patients after orthokeratology. 4) After orthokeratology, axial length change had negative correlation with the initial age (p = 0.001, r = -0.616) and residual diopter (p = 0.022). CONCLUSIONS: For myopes above refraction < -5.00D, wearing Ortho-k lenses overnight and glasses to correct the RRE in the daytime is recommended to ensure good visual quality and have more myopic RPRE for potential myopia control.

High-throughput screening of human mercury exposure based on a low-cost naked eye-recognized biosensing platform.

Whole-cell biosensors could be helpful for in situ disease diagnosis. However, their use in analyzing biological samples has been hindered by unstable responses, low signal enhancement, and growth inhibition in complex media. Here, we offered a solution by building a visual whole-cell biosensor for urinary mercury determination. With deoxyviolacein as the preferred signal for the mercury biosensor for the first time, it enabled the quantitative detection of urinary mercury with a favorable linear range from 1.57 to 100 nM. The biosensor can accurately diagnose urine mercury levels exceeding the biological exposure index with 95.8% accuracy. Thus, our study provided a biosensing platform with great potential to serve as a stable, user-friendly, and high-throughput alternative for the daily monitoring or estimating of urinary mercury.

Health-related quality of life for children using orthokeratology (OK), peripheral lenslet designed (PLD) and single-vision (SV) spectacles: based on Child Health Utility 9 Dimensions (CHU9D).

PURPOSE: This study investigated the health-related quality of life (HRQoL) among children with myopia who used orthokeratology (OK), peripheral lenslet designed (PLD), and single-vision (SV) spectacles. METHODS: This cross-sectional study was conducted between February of 2021 and August of 2022. It involved 211, 231, and 206 respondents with OK, PLD, and SV spectacle lenses, respectively. The HRQoL was presented as utility values using a general preference-based Child Health Utility-nine Dimensions (CHU9D) questionnaire. Descriptive statistical analysis and nonparametric hypothesis testing were used to compare the HRQoL in the OK, PLD, and SV groups. RESULTS: Of the 648 respondents, the average utility scores was 0.936 (95 % confidence interval (CI): 0.929-0.943). Children who wore the PLD spectacles had a significantly higher utility scores (0.955, 95 % CI: 0.946-0.963) than those who wore the SV spectacles (0.926, 95 % CI: 0.913-0.939) and the OK lenses (0.925, 95 % CI: 0.913-0.937) (p < 0.01). The PLD spectacle wearers were less likely to be worried, sad, tired, or annoyed than those who wore OK and SV spectacles (P < 0.05). Self-reported improved eyesight and lessened eye pain and discomfort from myopia correction using PLD spectacles had higher utility values (P < 0.05). CONCLUSIONS: The PLD spectacles had a significantly higher HRQoL than the OK and SV spectacles among children. Having better eyesight and less eye pain/discomfort from myopia correction could improve the HRQoL of children. This data indicates that PLD spectacles may be considered for myopia management in children and adolescents.

Studies on the Digital Inclusion Among Older Adults and the Quality of Life-A Nanjing Example in China.

Digital inclusion can bridge the digital divide and reduce the social exclusion of older adults, yet it is understudied in China. This research examined factors influencing the digital inclusion of older adults in China and the relationship between digital inclusion and quality of life. Data collected from 312 older people (M = 69.6 years old) in Nanjing were included in a multinomial logit model to tackle these questions. Their attitudes toward technology were the most significant factor predicting their digital inclusion. Other factors included party affiliation, living situation, personal average monthly income, occupation, and capacity for instrumental activities of daily living (IADLs). This study shows digital inclusion has a direct impact on quality of life. It also serves as an intermediate variable that affects older people's attitudes toward technology and their IADL capacities. Most importantly, digital inclusion promotes social integration of older adults and improves the quality of their lives. Hence, it should not be ignored. Older people's attitudes toward technology are one of the keys to promoting their digital inclusion.

Enhanced biosynthesis of the natural antimicrobial glyceollins in soybean seedlings by priming and elicitation.

Glyceollins are a class of antimicrobial prenylated pterocarpans produced in soybean seedlings upon fungus elicitation. Priming with reactive oxygen species (ROS) prior to elicitation with Rhizopus oligosporus/oryzae (R) was investigated for its potential to enhance glyceollin production. ROS-priming prior to R-elicitation (ROS + R) increased glyceollin production (8.6 ± 0.9 µmol/g dry weight (DW)) more than 4-fold compared to elicitation without priming (1.9 ± 0.4 µmol/g DW). Furthermore, ROS-priming was superior to two physical primers which were used as benchmark primers, namely slicing (5.0 ± 0.6 µmol glyceollins/g DW) and sonication (4.8 ± 1.0 µmol glyceollins/g DW). Subsequently, the robustness of ROS + R was assessed by applying it to another soybean cultivar, where it also resulted in a significantly higher glyceollin content than R-elicitation without priming. ROS-priming prior to elicitation provides opportunities for improving the yield in large-scale production of natural antimicrobials due to the ease of application and the robustness of the effect across cultivars.

[Determination of n-pentanol in workplace air by solvent desorption gas chromatography].

OBJECTIVE: To develop a solvent desorption gas chromatographic method for determination of n-pentanol in the workplace air. METHODS: n-Pentanol in the workplace air was collected with activated carbon tubes, desorbed with 2% 2-propanol in carbon disulfide, separated with a nitroterephthalic acid-modified FFAP capillary column, and detected with flame ionization detector. RESULTS: The limit of detection was 0.2 mg/L; the lower limit of quantification was 0.6 mg/L; the linear range was 0.6-4072.0 mg/L. The minimum detectable mass concentration was 0.2 mg/m3 for 1.5 L of air sample. This method was highly repeatable. The relative standard deviations were 2.3%-5.4%. The average desorption efficiencies were 86.9%-94.2%. The absorption efficiencies were 100%. The breakthrough volume was above 8.0 mg in 100-mg activated carbon. The samples in activated carbon tubes could be stored for at least 14 days at room temperature. CONCLUSION: The method is feasible for determination of n-pentanol in the workplace air.

[Determination of ethylene glycol in workplace air by capillary column gas chromatography].

OBJECTIVE: To establish the method of capillary column gas chromatography for determination of ethylene glycol in workplace air. METHODS: Ethylene glycol in workplace air was collected with silicone tube, desorbed with methanol, separated with FFAP (nitroterephthalic acid-modified polyethylene glycol)capillary column, and measured with flame ionization detector. RESULTS: The detection limit of ethylene glycol was 0.41 mg/L, the lower limit of quantification was 1.4 mg/L, the range of measurement was 1.4~163.9 mg/L, and the minimum detectable concentration was 0.3 mg/m3 (1.5 L of air was collected as the sample). This method had a good repeatability, the relative standard deviation was 1.4%~5.2%, the average desorption efficiency was 94.4%~101.7%, and the sampling efficiency was 99.2%~100%. The penetrating capacity of 200 mg silicone was higher than 6.9 mg, and the samples could be preserved for 14 days at room temperature. CONCLUSION: The method has a low detection limit, high accuracy, and good precision, which is feasible for determination of ethylene glycol in workplace air.

[Detecting the isoflurane in the air of workplaces with chromatographic method].

OBJECTIVE: To establish a solvent desorption Gas chromatographic method for detecting the isoflurane in air of workplaces. METHODS: This method is based on "Standardization of methods for determination of toxic substances in workplace air". RESULTS: This method presents the linear relation with the minimum detectable limit 1.0 µg/ml and the minimum detectable concentration 0.07 mg/m(3). The precision (RSD) was 0.5% ∼ 5.0%, the mean dsorption efficiencies were 96.7% ∼ 98.9%, the absorption efficiencies were 92.1% ∼ 100%, the breakthrough volume was 3.7 mg isoflurane/100 mg active carbon. Other volatile organic solvents (Sevoflurane, Enflurane and Ethyl Alcohol) did not interfere the detection. The sample could be stored in the active carbon tube at least for 10 days. CONCLUSION: This method is meet the requirement of GBZ/T 210.4-2008 "Guide for establishing occupational health standards-Part4: Determination methods of air chemicals in workplace" and is feasible for determining the isoflurane in the air of workplaces.

[Simultaneous determination of seven chemicals of halogenated alkanes and aromatic hydrocarbons in the air of workplace by gas chromatography].

OBJECTIVE: To establish a gas chromatographic method for determination of halogenated alkanes and aromatic hydrocarbons including trichloromethane, 1,2-dichloroethane, carbon tetrachloride, benzene, toluene, ethylbenzene and xylene in the air of workplace. METHODS: After the air samples collected with activated carbon tubes and desorbed with CS(2), the target toxicants were separated with FFAP capillary columns and detected with flame ionization detector. RESULTS: The coefficient of correlation was above 0.999 and the lowest detectable concentrations were 0.2 ∼ 3.6 mg/m(3) with the RSD of 1.2% ∼ 4.6%. The desorption efficiencies was 94.9% ∼ 100.7%. CONCLUSION: The method shows lower detection limit, high accuracy and precision. It is feasible for determination of the seven halogenated alkanes and aromatic hydrocarbons in the air of workplace.