Machado-Joseph disease, or spinocerebellar ataxia type 3 (SCA3), represents the most common autosomal dominant cerebellar ataxia worldwide. Despite its progressive and debilitating nature, disease-modifying therapies remain elusive. Repetitive transcranial magnetic stimulation (rTMS) has emerged as a promising non-invasive intervention; however, its clinical application has been hindered by inconsistent protocols and a lack of mechanistic understanding. A recent landmark study published in Brain Stimulation by Chen et al. addressed these challenges by combining a high-dose intermittent theta-burst stimulation (iTBS) protocol with concurrent transcranial magnetic stimulation-electroencephalography (TMS-EEG). This commentary provides an in-depth analysis of their findings, highlighting the restoration of cerebello-cortical inhibition (CBI) as a key therapeutic mechanism. Furthermore, we discuss the broader implications of this work, proposing that future translational research should integrate accelerated iTBS (aiTBS) paradigms, cortical response measurements (CRM), and individualized neuro-navigation to establish a new era of precision neuromodulation for ataxia.

Machado-Joseph disease, or spinocerebellar ataxia type 3 (SCA3), represents the most common autosomal dominant cerebellar ataxia worldwide. Despite its progressive and debilitating nature, disease-modifying therapies remain elusive. Repetitive transcranial magnetic stimulation (rTMS) has emerged as a promising non-invasive intervention; however, its clinical application has been hindered by inconsistent protocols and a lack of mechanistic understanding. A recent landmark study published in Brain Stimulation by Chen et al. addressed these challenges by combining a high-dose intermittent theta-burst stimulation (iTBS) protocol with concurrent transcranial magnetic stimulation-electroencephalography (TMS-EEG). This commentary provides an in-depth analysis of their findings, highlighting the restoration of cerebello-cortical inhibition (CBI) as a key therapeutic mechanism. Furthermore, we discuss the broader implications of this work, proposing that future translational research should integrate accelerated iTBS (aiTBS) paradigms, cortical response measurements (CRM), and individualized neuro-navigation to establish a new era of precision neuromodulation for ataxia.

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: This study aims to explore the influencing factors, formation mechanisms, and treatment methods of labial protuberance in the anterior maxilla during orthodontic treatment, providing a reference for clinical practice. Method: This study reports a case where the absence of upper anterior teeth 11 and 21, and the retraction tilting movement of teeth 12 and 22, resulted in labial protuberance and gingival hyperplasia. Alveolar osteoplasty and gingivoplasty were performed. The specific changes in the alveolar bone during the retraction of the anterior teeth and the characteristics of its remodeling were analyzed. Combined with relevant literature, the factors influencing the formation of labial protuberance in orthodontic patients, mechanisms, and methods for prevention and treatment were summarized. Results: After periodental surgery follow-up for 6 months, the gingival color and shape of teeth 12 and 22 were good, the labial alveolar bone was normal, and the overall condition was stable. A review of the literature showed that labial protuberance is more common in adult orthodontic patients, and the distance (>4 mm) and speed of retraction of anterior teeth are related to its formation, with the main mechanism likely being differential remodeling of the alveolar bone. In adult patients, the number of active osteoblasts and osteoclasts in the alveolar bone decreases, along with a reduction in metabolic activity and overall cellular activity, which diminishes the reactivity of the alveolar bone. After treatment of anterior teeth retraction, there is insufficient labial bone resorption. Moreover, the lack of mechanical stress-mediated periodontal ligament in the interdental space leads to reduced bone remodeling stimulation in this area, resulting in thickening of the labial alveolar bone of the upper anterior teeth. The remodeling rates of cortical and trabecular bone differ, with active trabecular bone proliferation near the tooth root surface and slow cortical bone resorption near the outer surface, which ultimately results in increased bone thickness at the labial cervical region. Specific case analysis indicates that the retraction distance of the upper anterior teeth in this case was about 6 mm. The alveolar bone at the missing sites of teeth 11 and 21, lacking periodontal ligament stimulation, showed less remodeling and absorption, likely appearing as hyperplasia. The prevention of labial bone protrusion mainly involves controlling the speed and distance of retraction of anterior teeth. Smaller labial protuberances generally do not require treatment, but those affecting function and aesthetics can be addressed with periodontal alveolar osteoplasty. Conclusion After the retraction of anterior teeth in orthodontics, a prominent, hard bone protuberance on the labial side can sometimes occur, which may be due to differential remodeling efficiency in different regions of the alveolar bone. For bone protuberance that influences aesthetics or function, periodontal alveolar osteoplasty can be a reliable option.

Objective To investigate the clinical characteristics of patients with clinical and subclinical Cushing's syndrome caused by primary bilateral macronodular adrenal hyperplasia(PBMAH).Methods A retrospective analysis was performed on the clinical data of 198 patients with Cushing's syndrome caused by PBMAH diagnosed in the First Medical Center of Chinese PLA General Hospital from January 2004 to October 2024.According to clinical manifestations,the patients were classified into clinical type Cushing's syndrome(n=61)and subclinical type Cushing's syndrome(n=137),and the clinical characteristics of the two types were compared.Results The mean age at diagnosis of patients with PBMAH-induced Cushing's syndrome was(53.5±10.4)years,including 118 males and 80 females,with a male-to-female ratio of 1.475:1.Compared with the subclinical type,the clinical type had a higher proportion of females,higher levels of serum cortisol,24-hour urine free cortisol(24 h UFC),and inhibited serum cortisol after low-dose dexamethasone suppression.Additionally,the clinical type had lower plasma ACTH,larger adrenal nodules and a higher risk of surgery(P<0.05)compared with those in subclinical type.The incidences of hypertension,dyslipidemia,obesity,diabetes mellitus,hypokalemia,vitamin D deficiency,osteoporosis,coronary heart disease,and cerebrovascular disease in patients with Cushing's syndrome caused by PBMAH were 87.9%,50.5%,37.1%,36.9%,27.8%,25.9%,18.7%,18.7%and 12.1%,respectively.Among them,compared with subclinical type patients,clinical type patients had higher incidence of hypokalaemia,vitamin D deficiency and osteoporosis(P<0.05),while there were no statistically significant differences in the incidences of other comorbidities between the two types(P>0.05).The results of postoperative follow-up for PBMAH patients showed that the short-term biochemical remission rate of unilateral total adrenalectomy was 41.5%(22/53)and the long-term biochemical remission rate was 32.0%(8/25).The short-term biochemical remission rate of unilateral partial(or nodular)adrenalectomy was 52.9%(9/17),and the long-term biochemical remission rate was 14.3%(1/7).All patients who underwent unilateral total adrenalectomy plus contralateral partial resection developed adrenal insufficiency(3/3),and 1 patient(1/3)relapsed 3.4 years after surgery.Conclusion Clinical and subclinical types of Cushing's syndrome caused by PBMAH have their distinct clinical characteristics.Surgery is an effective treatment for PBMAH,but a certain proportion of patients fail to achieve biochemical remission after non-bilateral total adrenalectomy.

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.

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.

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

As the chip of synthetic biology, enzymes play a vital role in the bio-manufacturing industry. The development of diverse functional enzymes can provide a rich toolbox for the development of synthetic biology. This article reports the construction of an artificial enzyme with the introduction of a non-natural cofactor. By introducing the 4-dimethylaminopyridine (DMAP) cofactor into the optimal protein skeleton via covalent bonds based on a click-chemistry strategy, we successfully constructed a novel artificial enzyme with the DMAP cofactor as the catalytic center. The artificial enzyme successfully catalyzed an unnatural asymmetric Morita-Baylis- Hillman (MBH) reaction between cycloketenone and p-nitrobenzaldehyde, with a conversion rate of 90% and enantioselectivity (e.e.) of 38%. This study not only provides an effective strategy for the design of new artificial enzymes but also establishes a theoretical basis for the development of unnatural biocatalytic MBH reactions.
Biocatalysis ; 4-Aminopyridine/chemistry* ; Enzymes/metabolism* ; Coenzymes/chemistry* ; Benzaldehydes/chemistry* ; Protein Engineering/methods* ; Click Chemistry