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.

Objective To comparatively analyze the clinical characteristics of primary bilateral macronodular adrenal hyperplasia(PBMAH)and adrenal cortisol-producing Adenoma(CPA),and enhance the understanding of two diseases.Methods The clinical data of 85 PBMAH patients(PBMAH group)and 195 CPA patients(CPA group)diagnosed at Department of Endocrinology,the First Medical Center of Chinese PLA General Hospital,from September 2014 to August 2024 were retrospectively analyzed.The demographic characteristics,comorbidities,biochemical indicators,adrenocorticotropic hormone-cortisol(ACTH-F)levels,and adrenal imaging features and treatment conditions were compared between the two groups.Results(1)General characteristics:Compared with CPA group,PBMAH group had older age at diagnosis and a higher proportion of male patients.(2)Clinical characteristics:Compared with CPA group,PBMAH group had a longer disease duration,a higher proportion of subclinical Cushing's syndrome(CS),and a higher proportion of hypertension,impaired glucose tolerance/diabetes,bone mass reduction or osteoporosis,with higher serum potassium levels,and the differences were statistically significant(P<0.01).(3)Hormone levels:Both PBMAH and CPA groups showed ACTH-F rhythm disorder,significantly increased cortisol levels and suppressed ACTH.Compared with PBMAH group,CPA group had stronger autonomous cortisol secretion ability,manifested by increased midnight serum cortisol(F0:00),16:00 serum cortisol(F16:00),24-hour urinary free cortisol(24 h UFC)levels and lower 8:00 serum ACTH(ACTH8:00)and 16:00 serum ACTH(ACTH16:00)(P<0.01).After low-dose dexamethasone suppression test(LDDST),CPA group showed lower suppression rates of ACTH and cortisol,and higher proportions of paradoxical elevation in serum cortisol and 24 h UFC compared with PBMAH(P<0.01).Conclusions PBMAH has a longer disease course and higher proportions of comorbid metabolic disorders than CPA,mostly manifested as subclinical Cushing's syndrome.CPA has stronger autonomous cortisol secretion ability,with cortisol less likely to be suppressed after LDDST and more obvious paradoxical elevation of cortisol and 24 h UFC.

Objective To investigate the clinical and pathological characteristics of adrenal cortical carcinoma(ACC),compare differences between hypercortisolism and non-functional ACC,and assess the diagnostic value of indicators such as Ki-67 index.Methods The clinical data of 57 ACC patients admitted to the First Medical Center of Chinese PLA General Hospital from January 2015 to March 2025 were retrospectively analyzed.According to the results of endocrine function assessment,47 of these patients were divided into hypercortisolism group(n=19)and non-functional group(n=28).The differences in clinical and pathological characteristics between the two groups were compared,and non-parametric tests and Spearman correlation analysis were used to explore the relationship between Ki-67 index and tumor stage as well as imaging features.Results Among the 57 patients,there were 20 males and 37 females,with a male-to-female ratio of 1:1.85.The age ranged from 16 to 76 years,and the age at diagnosis was(48.7±13.3)years.The tumor diameter was(10.53±4.14)cm.The tumors were located on the right side in 12 cases(21.1%),on the left side in 34 cases(59.6%),and bilaterally in 11 cases(19.3%).Among them,16 cases(28.1%)were complicated with glucose metabolism disorders,31 cases(54.3%)had hypertension,and 20 cases(35.1%)had hypokalemia.According to ENSAT staging,there were 0 cases in stage Ⅰ,15 cases(26.3%)in stage Ⅱ,24 cases(42.1%)in stage Ⅲ,and 18 cases(31.6%)in stage Ⅳ.Endocrine function assessment was completed in 47 of the 57 patients,including 28 cases(59.6%)of non-functional ACC and 19 cases(40.4%)of hypercortisolism(including 1 case of hypercortisolism combined with increased sex hormone secretion).Compared with non-functional group,hypercortisolism group had a significantly higher prevalence of hypertension(P=0.014),later ENSAT stage(P=0.010),and a higher proportion of hypervascularization(P=0.048).The median Ki-67 index was 20%(10%-40%),showing no significant correlation with either the maximum tumor diameter or SUVmax value,but it was related to ENSAT staging,with Ki-67 index in stageⅣ patients being significantly higher than that in stage Ⅱ(P=0.032).Immunohistochemistry results showed that the positive rate of Inhibin-α was 84.8%,and the positive rate of Melan-A was 40.9%.Conclusions ACC is a rare malignant endocrine tumor.ACC patients with hypercortisolism are more likely to be complicated with hypertension,have later staging,and more common hypervascular manifestations.Clinically,their endocrine function should be prioritized for assessment,and more active treatment strategies should be adopted.Diagnosis should be combined with imaging characteristics(such as hypervascularization)and immunohistochemical indicators(Ki-67,Inhibin-α,Melan-A).The significant increase in Ki-67 is in the advanced stage can serve as an important prognostic indicator to guide individualized treatment.

Objective To characterize multimodal metabolic disorders in subclinical Cushing's syndrome(SCS)patients with different cortisol levels,providing a reference for clinical diagnosis and treatment.Methods A retrospective analysis was conducted on the clinical data of 165 SCS patients diagnosed at the First Medical Center of Chinese PLA General Hospital due to adrenal masses from January 2014 to October 2024.Using the serum cortisol levels after the midnight 1 mg dexamethasone suppression test(1 mg DST)as the cut-off point,SCS patients were divided into high-level group(1 mg DST-F>138 nmol/L,n=96)and low-level group(50 nmol/L<1 mg DST-F≤138 nmol/L,n=69).The differences in age,gender,body mass index(BMI),blood pressure,glucolipid metabolism indices,electrolytes,hormone levels,and imaging features of adrenal adenoma(such as CT values)were compared between the two groups.Multivariate linear regression was used to analyze the correlation between CT values and metabolic indices.Results Compared with low-level group,patients in high-level group were younger(54.0±11.3 vs.57.7±10.3,P=0.034),while there were no statistically significant differences in gender ratio or BMI between the two groups(P>0.05).Both groups exhibited decreased adrenocorticotropic hormone(ACTH)levels and disrupted circadian rhythm.Compared with low-level group,high-level group showed significantly higher F0:00 levels[250.00(170.07,422.53)nmol/L vs.110.00(82.74,133.90)nmol/L]and 24-hour urinary free cortisol(24 h UFC)[568.40(377.80,875.45)nmol/24 h vs.369.40(265.40,494.69)nmol/24 h](P<0.001),with no significant differences in serum F8:00,or 1 mg DST ACTH0:00 levels(P>0.05).Except for the fasting C-peptide level in the high-level group being higher than that in low-level group[(2.88±1.01)ng/ml vs.(2.46±0.78)ng/ml,P=0.024],there were no significant differences in blood pressure,blood lipids,glycated hemoglobin(HbA1c),fasting blood glucose,fasting insulin,serum electrolytes,uric acid,and other indices between the two groups(P>0.05).The CT value of adrenal adenoma during contrast-enhanced scanning was higher in high-level group[80.00(17.80,93.00)Hu vs.52.00(35.50,75.00)Hu,P=0.006]compared with low-level group.Multivariate linear regression analysis revealed that diastolic blood pressure was positively correlated with CT values of adrenal adenomas in both plain scanning(β=0.49,95%CI 0.09-0.90)and contrast-enhanced scanning(β=2.08,95%CI 0.76-3.39),while triglyceride levels were negatively correlated with plain scanning CT values(β=-5.77,95%CI-10.88--0.66).Conclusion Patients with SCS at different cortisol levels differ in age,fasting C-peptide levels,and CT values.CT values may serve as potential imaging markers to assess metabolic risk in SCS patients.

Objective To summarize the clinical characteristics of primary pigmented nodular adrenocortical disease(PPNAD)and provide a reference for its clinical diagnosis and treatment.Methods A retrospective analysis was conducted on the clinical characteristics,laboratory tests,imaging examinations,treatment plans,and follow-up data of 10 PPNAD patients diagnosed and treated at the First Medical Center of Chinese PLA General Hospital from January 2008 to October 2024.Databases including CNKI,Wanfang Data Knowledge Service Platform,and PubMed were searched,and the clinical characteristics of 120 PPNAD patients reported in the literature were summarized in combination with literature reviews.Results The age at diagnosis of the 10 PPNAD patients ranged from 15 to 55 years,with a median age of onset of 21.5 years.Seven patients had the protein kinase A regulatory subunit 1 alpha(PRKAR1A)gene mutations,meeting the diagnosis criteria for Carney syndrome.One patient presented with hypertension only,while the remaining 9 patients showed typical Cushing's syndrome manifestations such as thin skin and moon face,among whom 5 experienced stagnation of height growth.In 7 patients,the adrenocorticotropic hormone(ACTH)levels were<2.2 pmol/L,with the disrupted circadian rhythm of cortisol,and the cortisol levels at midnight ranged from 243.24 to 679.83 pmol/L.None of the patients showed suppression in the low-dose dexamethasone suppression test,and 8 patients had an increase in urinary free cortisol(UFC)after dexamethasone suppression.Adrenal CT showed that 9 patients presented with unilateral adrenal nodules accompanied by contralateral thickening or bilateral adrenal nodular thickening.All 10 patients underwent initial unilateral adrenalectomy,and during follow-up,4 patients experienced symptom recurrence and underwent contralateral adrenalectomy.Most of the 120 patients reported domestically and internationally showed typical Cushing's syndrome manifestations.Surgical resection of the adrenal gland was the main treatment modality.Gene mutations were predominantly in PRKAR1A,with a few in PDE11A and PRKACA.Conclusions PPNAD is more likely to occur in adolescents.Patients with typical Cushing's syndrome manifestations should undergo screening.Imaging manifestations are atypical,and a definitive diagnosis depends on pathological and genetic diagnoses.Bilateral adrenalectomy combined with long-term postoperative hormone replacement therapy is the standard treatment protocol.Patients who undergo early unilateral adrenalectomy require long-term follow-up,with contralateral adrenalectomy performed when necessary.

Objective To report a case of tibial synovial sarcoma and review relevant literature to enhance understanding of this disease.Methods The clinical data of a patient with tibial synovial sarcoma treated at Kaifeng Central Hospital were retrospectively analyzed.A literature search was conducted in domestic and international databases,including China National Knowledge Infrastructure(CNKI),Wanfang Data,PubMed,Web of Science,and Embase,up to July 2024.Relevant literature was comprehensively reviewed to summarize the imaging and pathological characteristics,treatment,and prognosis of synovial sarcoma.Results A 29-year-old female patient was admitted with left lower extremity pain.X-ray examination revealed a proximal tibia space-occupying lesion suggestive of malignancy,and a mid-tibial space-occupying lesion considered benign.Contrast-enhanced computed tomography(CT)and plain magnetic resonance imaging(MRI)of the proximal tibial lesion also suggested malignancy.Ultrasound-guided biopsy of the proximal tibial tumor revealed a poorly differentiated malignant tumor.Immunohistochemistry results indicated monophasic synovial sarcoma,requiring genetic testing for definitive diagnosis.The patient underwent wide resection of the proximal left tibial malignancy with tumor-type artificial joint replacement,combined with curettage and bone cement filling for the left mid-tibial lesion under anesthesia.Postoperative pathology of space-occupying lesions in the proximal tibia confirmed monophasic synovial sarcoma,and fluorescence in situ hybridization(FISH)demonstrated a rupture of the synovial sarcoma translocation gene(SYT)(i.e.,SS18 positive).There was no recurrence or metastasis found in the patient during the reexamination 6 months after postoperative chemotherapy.As of July 2024,15 cases of genetically confirmed primary intraosseous synovial sarcoma have been reported internationally.Symptoms included pain and swelling,with a medical history of 1-2 years.The X-ray and CT findings showed osteolytic destruction with bone cortical discontinuity.In 13 cases,the intraosseous masses extended to the extraosseous area;in 2 cases,punctate calcifications were detected within the masses.Plain MRI scan showed iso-signal or hypo-signal on T1WI and hyper-signal,iso-signal,and hypo-signal on fat-suppressed T2WI,and enhanced MRI scan demonstrated heterogeneous enhancement.Pathological examination showed spindle-shaped cells under microscopy.Immunohistochemistry results showed positive epithelial membrane antigen(EMA),broad-spectrum cytokeratin(AE1/AE3),Ewing's sarcoma marker(CD99),and transducin-like enhancer of Split 1(TLE1).Twelve patients underwent surgical treatment;6 patients received adjuvant chemotherapy after surgery,of whom 4 developed local recurrence or distant metastasis at initial diagnosis,and 3 died during follow-up.Among the 6 patients who did not receive adjuvant chemotherapy,3 suffered from recurrence or distant metastasis.Conclusions Primary intraosseous synovial sarcoma is a rare malignant tumor with non-specific clinical manifestations.Imaging features typically include osteolytic destruction and intraosseous masses extending extraosseously,suggesting an intraosseous origin.Pathology and immunohistochemistry aid diagnosis,but definitive confirmation relies on further genetic testing.At present,the main treatment regimens for synovial sarcoma involve comprehensive therapies such as surgery and adjuvant chemotherapy,and the prognosis of patients is poor.

This article reports a first case of combined infection with severe fever with thrombocytopenia syndrome(SFTS)and scrub typhus in Dalian City.The patient was admitted to the hospital due to recurrent fever for 7 days and loss of consciousness for 1 day.Pathogen metagenomic sequencing(mNGS),SFTSV quantitative PCR,and enzyme-linked immunosorbent assay(ELISA)IgM tests were performed,showing positive results for Orientia tsutsugamushi and SFTSV nucleic acids.Based on clinical manifestations and epidemiological history,the patient was diagnosed with combined infections.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

Mutations in the cyclin-dependent kinase-like 5 gene (CDKL5) cause a severe neurodevelopmental disorder, yet the impact of truncating mutations remains unclear. Here, we introduce the Cdkl5^492stop mouse model, mimicking C-terminal truncating mutations in patients. 492stop/Y mice exhibit altered dendritic spine morphology and spontaneous seizure-like behaviors, alongside other behavioral deficits. After creating cell lines with various Cdkl5 truncating mutations, we found that these mutations are regulated by the nonsense-mediated RNA decay pathway. Most truncating mutations result in CDKL5 protein loss, leading to multiple disease phenotypes, and offering new insights into the pathogenesis of CDKL5 disorder.
Animals ; Disease Models, Animal ; Mice ; Protein Serine-Threonine Kinases/deficiency* ; Mutation/genetics* ; Epileptic Syndromes/genetics* ; Humans ; Dendritic Spines/pathology* ; Spasms, Infantile/genetics* ; Male ; Seizures/genetics* ; Mice, Inbred C57BL