Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Background: As Taiwan’s population ages, falls among older adults have become a critical public health concern. However, limited data exist regarding temporal trends and injury patterns in fall-related emergency department (ED) visits. This study aimed to examine trends in fall-related ED visits and hospitalizations among older adults in Taiwan and to explore injury distributions by age group. Methods: We conducted a retrospective cohort study using data from the National Taiwan University Hospital between 2011 and 2017. Patients aged ≥65 years were compared with those aged 20–64 years. Fall-related visits were identified using chief complaints and the International Classification of Diseases 9th/10th revision (ICD-9/ICD-10) codes. Outcomes included hospitalization rates, length of stay, and 30-day mortality. Results: A total of 22,471 fall-related ED visits were analyzed. While visits among younger adults declined (annual growth rate, -1.34%), visits among older adults increased (2.37% annually), with the steepest rise in those aged ≥85 years. Hospitalization occurred in 27.1% of older adults, nearly double that of younger adults (14.4%). Older adults also had longer hospital stays and higher 30-day mortality rates, findings consistent even when restricted to lower limb fractures. Conclusion Fall-related ED visits and hospitalizations are rising disproportionately among Taiwan’s older population. Targeted prevention strategies and transitional care interventions are urgently needed to address the growing clinical and economic burden of falls in aging societies.

Objective: To develop and validate a clinically actionable prediction model for postoperative pulmonary complications (PPCs) in cardiac surgery patients, focusing on modifiable preoperative risk factors amenable to targeted optimization. Methods: In this prospective observational cohort study, 492 adults undergoing open-chest cardiac surgery between August 15, 2023 and December 31, 2023 were analyzed. Prespecified predictors included gas exchange variables, pulmonary function, inspiratory muscle strength, and physical performance. Univariable and multivariable logistic regression analyses were used to develop the prediction model. Discrimination was assessed by the area under the receiver operating characteristic curve (AUC). Results: A total of 90 patients (14.1%) developed PPCs after surgery. Five independent predictors were identified: elevated arterial PaCO2 (odds ratio [OR] 1.12, 95% confidence interval [CI] 1.00–1.26), oxygen desaturation (SpO2<93%) (OR 12.47, 95% CI 3.51–48.13), reduced gait speed (OR 0.17, 95% CI 0.04–0.71), lower FEV1/FVC ratio (OR 0.96, 95% CI 0.92–1.00), and diminished inspiratory muscle strength (MIP % predicted) (OR 0.96, 95% CI 0.92–0.99). The model demonstrated good discriminative ability with an AUC of 0.86 (95% CI 0.80–0.93) in the training cohort and 0.87 (95% CI 0.74–0.93) in the validation cohort. Conclusion This parsimonious model achieved high predictive accuracy using five modifiable physiological variables. By targeting abnormalities in gas exchange, pulmonary mechanics, muscle strength, and functional reserve, the model offers a practical tool to guide individualized prehabilitation strategies for reducing PPC risk in cardiac surgery patients.

Objective To analyze the epidemiological characteristics of poisonous mushroom-related foodborne disease incidents in Chongqing from 2010 to 2024, and to provide a scientific basis for effective prevention and control of mushroom-related foodborne diseases. Methods Data of poisonous mushroom related foodborne disease incidents reported by the CDCs of 39 districts and counties in Chongqing from 2010 to 2024 were collected, and their epidemic characteristics were analyzed. Results A total of 264 poisonous mushroom poisoning outbreaks were reported in Chongqing from 2010 to 2024, resulting in 1 046 cases of illness, 543 hospitalizations, and 15 deaths, with a mortality rate of 1.43%. The peak of poisoning incidents was from June to October, accounting for 89.02% of the total number of incidents. The top three high-incidence areas were Pengshui Miao Tujia Autonomous County, Dianjiang County, and Nanchuan District. Poisonous mushroom poisoning incidents occurring in household settings, accidental picking and ingestion, and cases involving unidentified mushroom species accounted for 89.02%, 83.33%, and 90.15% of all foodborne disease outbreak incidents, respectively. Conclusion Foodborne disease incidents related to poisonous mushrooms in Chongqing City show an upward trend, and the effectiveness of prevention and control needs to be improved. Based on their seasonal, regional and household clustering characteristics, efforts should be made before the peak season of mushroom poisoning in high-risk areas, targeting key populations with health education, monitoring and early warning, food safety supervision, and medical treatment.

Introducing fingerprint level 3 features(especially sweat pores)in fingerprint recognition can significantly improve the value of fingerprints.However,conventional fingerprint visualization methods suffer from issues such as poor stability and reproducibility,insufficient resolution,and feature masking in detecting level 3 features.Electrospun membrane has unique advantages in latent fingerprint(LFP)detection due to its excellent adsorption performance and high specific surface area,and thus its application potential in LFP visualization urgently need to be explored.A novel pore visualization method based on core-shell structured PAN-Flu/PVP composite nanofibrous membrane was proposed in this work.Specifically,the PAN-Flu/PVP composite nanofibrous membrane was prepared via coaxial electrospinning technology,with polyacrylonitrile(PAN)loaded with fluorescein(Flu)as the core and polyvinylpyrrolidone(PVP)as the shell.The experimental results showed that the prepared PAN Flu/PVP composite nanofibrous membrane had a porous structure and excellent adsorption performance.Based on the water solubility of the outer shell PVP and the water induced fluorescence enhancement effect of the core Flu,high-resolution visualization of sweat pores could be achieved within 2 s.The optimization experiment showed that the best quality of sweat latent fingerprints was obtained when the Flu content was 4 mg/mL,the spinning time was 1 h,and the sweating time was 2 min.Through repeated fingerprinting and live fingerprint comparison experiment,the strong stability and high reproducibility of the as-produced membrane in displaying fingerprint sweat pores were finally verified.In summary,the development method could quickly,stably and accurately extract the spatial distribution and activity level of fingerprint sweat pores,which was of great significance for improving the utilization and value of fingerprints.

A method was developed for determination of dilauryl thiodipropionate(DLTDP)in fried foods by coupling solid-phase extraction(SPE)pretreatment with reverse-phase liquid chromatography-tandem mass spectrometry(RPLC-MS/MS)detection.Samples were extracted with n-hexane as the solvent,purified using a neutral alumina SPE cartridge,and finally analyzed by RPLC-MS/MS.Quantitative analysis was performed using matrix-matched calibration curves combined with an external standard method under optimal experimental conditions.The results showed that DLTDP exhibited good linearity in the range of 2.0-50.0 μg/L,with a correlation coefficient(R2)≥0.999.The limit of detection(LOD)and the limit of quantification(LOQ)of the method were 0.15 mg/kg and 0.5 mg/kg,respectively.The mean recoveries at three fortification levels(0.5,1.0,and 200 mg/kg)in different samples ranged from 84.8%to 96.8%,with the relative standard deviations(RSDs)all less than 8.0%.The developed method was highly sensitive,accurate and reliable,and easy to operate,making it well suited for the routine quantitative analysis of DLTDP in fried foods.

In this study,an ultraviolet(UV)/fluorescence dual-modal sensor was constructed by combining the catalytic properties of aldehyde dehydrogenase(ALDH)with the fluorescence inner filter effect of bovine serum albumin(BSA),realizing highly sensitive and highly selective detection of acetaldehyde in food.Acetaldehyde could react with oxidized coenzyme I(NAD+)to generate acetic acid and reduced coenzyme I(NADH)under catalytic condition by ALDH,and a quantitative relationship between acetaldehyde concentration and UV signal for UV detection based on the characteristic UV absorption peak of NADH at 340 nm was established.Meanwhile,an acetaldehyde detection channel based on fluorescence signal changes was built on the basis of the property that the fluorescence emission of BSA(as a fluorescent indicator)at 340 nm could be effectively quenched by the generated NADH,thus forming a″one-reaction dual-signal″detection mode.The experimental results showed that the acetaldehyde concentration in the range of 0.01?5.0 mg/L had a good linear relationship with both UV and fluorescence signals,and the limit of detection(LOD)was 0.003 mg/L for the UV mode and 0.005 mg/L for the fluorescence mode,and no significant fluctuations were observed when 50-fold concentrations of acetaldehyde analogs and common interfering substances were added.When the dual-modal sensor was applied to detection of acetaldehyde in food samples such as yogurt and wine,the relative error between its quantitative results and those of high-performance liquid chromatography(HPLC)was less than±4.0%.The dual-modal cross-validation strategy could improve the detection reliability through signal mutual verification,providing an innovative solution for the rapid detection of acetaldehyde contamination in food.

Objective To verify the efficacy of a domestic human DNA quantification kit based on real-time fluorescence quantitative PCR in detecting the total human DNA concentration,male DNA concen-tration in mixed male/female DNA samples,the degree of DNA degradation and inhibitor tolerance.Methods Samples with different concentrations,different male/female ratios,different concentrations of inhibitors,and different degradation degrees were tested using the domestic human DNA quantification kit based on real-time fluorescence quantitative PCR.This kit was compared with a similar product on the market and was applied to the detection of DNA from real cases.Results This human DNA quan-tification kit can effectively detect human DNA as low as 0.001 65 ng/μL,and 6.25 pg/μL of male DNA in mixed samples with a male-to-female ratio of 1∶15 000.Even when the sample contains as high as 400 ng/μL of humic acid or 1 000 μmol/L of hemin alone,the DNA concentration can still be accurately detected.The degradation index can effectively characterize the degradation degree of the sample.This kit has been successfully applied in forensic practice.Conclusion This human DNA quan-tification kit is accurate and reliable in detection.It can accurately reflect the degradation of DNA and inhibitor tolerance.It has good performance in quantitative accuracy,determination of the male/female ratio in mixed samples,and inhibitor tolerance.It has application potential in forensic case examination.

[This corrects the article DOI: 10.11909/j.issn.1671-5411.2017.08.005.].