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1.
Neuropharmacology ; : 110166, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39374769

RESUMEN

Excessive activation of mTOR has been observed in the brains of mouse models for Dravet syndrome. We aim to confirm whether that the overactivation of mTOR contributes to the neuropathological changes leading to epileptogenesis and neurobehavior deficits to support a novel pharmacological therapeutic approach for Dravet syndrome. The mTOR inhibitor everolimus, as a clinical antiseizure medication, was utilized to investigate whether mTOR is involved in hyperthermia-induced seizures, anxiety-like, and autism-like behaviors, as well as to explore potential pathogenic mechanisms in Scn1aE1099X/+ mice, a model of Dravet syndrome. First, we found that mTOR signaling was upregulated in hippocampus tissues and neural cultures derived from Scn1aE1099X/+ mice prior to seizure onset. Behaviorally, everolimus increased the seizure threshold and improved anxiety-like and autism-like behaviors in Scn1aE1099X/+ mice. Electrophysiologically, everolimus reduced the frequency of spontaneous excitatory postsynaptic currents in dentate granule neurons from Scn1aE1099X/+ mice. Biochemically, everolimus prevented hyperthermia-induced phosphorylation of hippocampal S6 ribosome in hippocampus, and it delayed hyperthermia-induced increase of cytosolic Ca2+ level in primary neuronal cultures derived from Scn1aE1099X/+ mice. Our results provide the evidence that overactivated mTOR as an important neuropathological change which regulates seizure threshold, impairments of neurobehavior, neuronal glutamatergic transmission and intracellular Ca2+ levels in Scn1aE1099X/+ mice. Inhibition of mTOR is a potential pharmacological therapeutic approach.

2.
Proc Natl Acad Sci U S A ; 121(42): e2401950121, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39378086

RESUMEN

Anthropogenic activities emit ~2,000 Mg y-1 of the toxic pollutant mercury (Hg) into the atmosphere, leading to long-range transport and deposition to remote ecosystems. Global anthropogenic emission inventories report increases in Northern Hemispheric (NH) Hg emissions during the last three decades, in contradiction with the observed decline in atmospheric Hg concentrations at NH measurement stations. Many factors can obscure the link between anthropogenic emissions and atmospheric Hg concentrations, including trends in the reemissions of previously released anthropogenic ("legacy") Hg, atmospheric sink variability, and spatial heterogeneity of monitoring data. Here, we assess the observed trends in gaseous elemental mercury (Hg0) in the NH and apply biogeochemical box modeling and chemical transport modeling to understand the trend drivers. Using linear mixed effects modeling of observational data from 51 stations, we find negative Hg0 trends in most NH regions, with an overall trend for 2005 to 2020 of -0.011 ± 0.006 ng m-3 y-1 (±2 SD). In contrast to existing emission inventories, our modeling analysis suggests that annual NH anthropogenic emissions must have declined by at least 140 Mg between the years 2005 and 2020 to be consistent with observed trends. Faster declines in 95th percentile Hg0 values than median values in Europe, North America, and East Asian measurement stations corroborate that the likely cause is a decline in nearby anthropogenic emissions rather than background legacy reemissions. Our results are relevant for evaluating the effectiveness of the Minamata Convention on Mercury, demonstrating that existing emission inventories are incompatible with the observed Hg0 declines.

3.
Noncoding RNA Res ; 9(4): 1351-1362, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39247145

RESUMEN

Prostate cancer (PCa) has the highest frequency of diagnosis among solid tumors and ranks second as the primary cause of cancer-related deaths. Non-coding RNAs (ncRNAs), such as microRNAs, long non-coding RNAs and circular RNAs, frequently exhibit dysregulation and substantially impact the biological behavior of PCa. Compared with circulating ncRNAs, ncRNAs loaded into exosomes are more stable because of protection by the lipid bilayer. Furthermore, exosomal ncRNAs facilitate the intercellular transfer of molecules and information. Increasing evidence suggests that exosomal ncRNAs hold promising potential in the progression, diagnosis and prognosis of PCa. This review aims to discuss the functions of exosomal ncRNAs in PCa, evaluate their possible applications as clinical biomarkers and therapeutic targets, and provide a comprehensive overview of the ncRNAs regulatory network in PCa. We also identified ncRNAs that can be utilized as biomarkers for diagnosis, staging, grading and prognosis assessment in PCa. This review offers researchers a fresh perspective on the functions of exosomal ncRNAs in PCa and provides additional options for its diagnosis, progression monitoring, and prognostic prediction.

4.
Nano Lett ; 24(38): 11847-11852, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39264273

RESUMEN

The pseudomagnetic field effect may offer unique opportunities for the emergence of intriguing phenomena. To date, investigations into pseudomagnetic field effects on phonons have been limited to sound waves in metamaterials. The revelation of this exotic effect on the atomic vibration of natural materials remains elusive. Our simulations of twisted graphene nanoribbons reveal well-defined Landau spectra and sublattice polarization of phonon states, mimicking the behavior of Dirac Fermions in magnetic fields. Both valley-specified helical edge currents and snake orbits are obtained. Analysis of dynamics indicates that phonon Landau states have extended lifetimes, which are crucial for the realization of Landau-level lasing. Our findings demonstrate the occurrence of the phonon pseudomagnetic field effect in natural materials, which has important implications for the mechanical tuning of phonon quantum states at the atomic scale.

5.
Medicine (Baltimore) ; 103(36): e39088, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39252257

RESUMEN

RATIONALE: Approximately one-fifth ischemic stroke are attributed to cardioembolism. Patients with cardioembolic stroke often develop a more severe disability and a higher risk of stroke recurrence. Cardiac myxoma, although uncommon, can serve as a potentially curable cause of acute embolic strokes. PATIENT CONCERNS: A 55-year-old male patient presented to the emergency department with acute vertigo and unsteady gait, accompanied by left upper limb numbness. Concurrently, purple-like lesions on the left hand were noticed. DIAGNOSES: Brain magnetic resonance imaging showed multiple infarctions in the posterior circulation. Additionally, skin examination showed Janeway lesions, Osler nodes and splinter hemorrhages. There was no evidence of systemic infection. Subsequently, transthoracic echocardiogram revealed a left atrial myxoma. INTERVENTION: Early surgical resection of cardiac myxoma was performed. OUTCOMES: The patient recovered well from the surgery. No recurrent embolic event was reported at 3-month postoperatively. LESSONS: Clinicians should be vigilant for skin manifestations of cardiac embolism. In patients with acute ischemic strokes, the presence of cutaneous embolic phenomena could serve as a warning sign of cardioembolism.


Asunto(s)
Atrios Cardíacos , Neoplasias Cardíacas , Accidente Cerebrovascular Isquémico , Mixoma , Humanos , Masculino , Mixoma/complicaciones , Mixoma/diagnóstico , Mixoma/cirugía , Persona de Mediana Edad , Neoplasias Cardíacas/complicaciones , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirugía , Accidente Cerebrovascular Isquémico/etiología , Atrios Cardíacos/diagnóstico por imagen , Endocarditis/complicaciones , Endocarditis/diagnóstico , Ecocardiografía
6.
ACS Nano ; 18(37): 25478-25488, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39236319

RESUMEN

SnSe, an environmental-friendly group-IV monochalcogenide semiconductor, demonstrates outstanding performance in various applications ranging from thermoelectric devices to solar energy harvesting. Its ultrathin films show promise in the fabrication of ferroelectric nonvolatile devices. However, the microscopic identification and manipulation of point defects in ultrathin SnSe single crystalline films, which significantly impact their electronic structure, have been inadequately studied. This study presents a comprehensive investigation of point defects in monolayer SnSe films grown via molecular beam epitaxy. By combining scanning tunneling microscopy (STM) characterization with first-principles calculations, we identified four types of atomic/molecular vacancies, four types of atomic substitutions, and three types of extrinsic defects. Notably, we have demonstrated the ability to convert a substitutional defect into a vacancy and to reposition an adsorbate by manipulating a single atom or molecule using an STM tip. We have also analyzed the local atomic displacement induced by the vacancies. This work provides a solid foundation for engineering the electronic structure of future SnSe-based nanodevices.

7.
Angew Chem Int Ed Engl ; : e202415637, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39327548

RESUMEN

In contrast to the high efficiency of room temperature phosphorescence in crystal states, the generally utilized nanoparticles of organic materials in bioimaging demonstrated sharply decreased performance by orders of magnitude under physiological conditions, badly limiting the realization of their unique advantages. This case, especially for organic red/near-infrared (NIR) phosphorescence materials, is not only the challenge present in reality but more importantly, for the theoretical problem of deeply understanding and avoiding the quenching effect by oxygen and water toward excited triplet states. Herein, thanks to the intelligent molecular design by the introduction of abundant hydrophobic chains and highly-branched structures, bright and persistent red/NIR phosphorescence under physiological conditions has been realized, which demonstrated the shielding effect towards oxygen, and strengthened the intermolecular interactions to suppress the non-radiative transitions. Accordingly, the record phosphorescence intensity of nanoparticles in bioimage, up to 8.21 ± 0.36 × 108 p s-1 cm-2 sr-1, was achieved, to realize the clear phosphorescence imaging of liver and tumors in living mice, even lymph nodes in rabbit models with high SBRs. This work afforded an efficient way to achieve the bright red/NIR phosphorescence nanoparticles, guiding their further applications in biology and medicine.

8.
Aging Clin Exp Res ; 36(1): 193, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39311977

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is a significant health concern, particularly among older adults. Outcomes between laparoscopic and robot-assisted surgeries for right-sided colon cancers in the oldest old population have yet to be evaluated despite increased use of these surgeries. AIM: This study aimed to compare clinical outcomes after robot-assisted right hemicolectomy (RARH) versus laparoscopic right hemicolectomy (LRH) in octogenarian and nonagenarian patients. METHODS: This population-based, retrospective and observational study analyzed the data of adults ≥ 80 years old diagnosed with right-side colon cancer who received RARH or LRH. All data were extracted from the US National Inpatient Sample (NIS) database 2005-2018. Associations between type of surgery and in-hospital outcomes were determined using univariate and multivariable logistic regression and linear regression analysis. RESULTS: Data of 7,550 patients (representing 37,126 hospitalized patients in the U.S.) were analyzed. Mean age of the study population was 84.8 years, 61.4% were females, and 79.1% were non-smokers. After adjusting for relevant confounders, regression analysis showed that patients undergoing RARH had a significantly shorter LOS (adjusted Beta (aBeta), -0.24, 95% CI: -0.32, -0.15) but greater total hospital costs (aBeta, 26.54, 95% CI: 24.64, 28.44) than patients undergoing LRH. No significant differences in mortality, perioperative complications, and risk of unfavorable discharge were observed between the two procedures (p > 0.05). Stratified analyses by frailty status revealed consistent results. CONCLUSIONS: RARH is associated with a significantly shorter LOS but higher total hospital costs than LRH among octogenarians and nonagenarians. Other short-term outcomes for this population are similar between the two procedures, including in-hospital mortality, perioperative complications, and unfavorable discharge. These findings also apply to frail patients.


Asunto(s)
Colectomía , Laparoscopía , Procedimientos Quirúrgicos Robotizados , Humanos , Femenino , Masculino , Colectomía/métodos , Laparoscopía/métodos , Laparoscopía/estadística & datos numéricos , Anciano de 80 o más Años , Procedimientos Quirúrgicos Robotizados/métodos , Procedimientos Quirúrgicos Robotizados/estadística & datos numéricos , Estudios Retrospectivos , Estados Unidos/epidemiología , Pacientes Internos , Tiempo de Internación , Resultado del Tratamiento , Complicaciones Posoperatorias/epidemiología , Neoplasias del Colon/cirugía , Neoplasias del Colon/mortalidad
9.
J Psychosom Res ; 187: 111936, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39306900

RESUMEN

OBJECTIVE: Though the association between peripheral neurophysiological biomarkers and psychological conditions is widely discussed, there is still limited evidence about the ability of peripheral biomarkers to predict psychological outcomes, especially among geriatric populations. METHODS: The study is designed as a prospective cohort study. We collected information from participants aged over 55 years. The participants were evaluated at the start of the study (T0) and 6-9 months later (T1). Information about demographic profiles, peripheral neurophysiological biomarker recordings (including heart rate variability, finger temperature, skin conductance, and electromyogram), and psychological measurements (including Brief Symptom Rating Scale-5, Chinese Happiness Inventory, and Short Portable Mental Status Questionnaire) were collected at T0. At T1, participants reported self-rated questionnaires for psychological outcomes (Patient Health Questionnaire-15, health anxiety questionnaire, Beck Depression Inventory-II, and Beck Anxiety Inventory) and were evaluated with Mini-Mental State Examination by the staff. The association between the peripheral biomarkers and psychological outcomes was evaluated via multiple regression models. RESULTS: A total of 385 participants were included in the study and the average age was 74.49 ± 7.34 years. Both stepwise multiple linear and logistic models showed a significant association between decreased skin conductance and increased/presence of depression at T1. The receiver operating characteristic (ROC) curve analysis of skin conductance for depression was fair (area under curve = 0.812). CONCLUSIONS: The ability of skin conductance to predict depression among geriatric populations may facilitate the detection of geriatric depression and future research on the pathophysiology.

10.
bioRxiv ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39211079

RESUMEN

Monocyte-derived macrophages recruited to injured tissues induce a maladaptive fibrotic response characterized by excessive production of collagen by local fibroblasts. Macrophages initiate this programming via paracrine factors, but it is unknown whether reciprocal responses from fibroblasts enhance profibrotic polarization of macrophages. We identify macrophage-fibroblast crosstalk necessary for injury-associated fibrosis, in which macrophages induced interleukin 6 ( IL-6 ) expression in fibroblasts via purinergic receptor P2rx4 signaling, and IL-6, in turn, induced arginase 1 ( Arg1 ) expression in macrophages. Arg1 contributed to fibrotic responses by metabolizing arginine to ornithine, which fibroblasts used as a substrate to synthesize proline, a uniquely abundant constituent of collagen. Imaging of idiopathic pulmonary fibrosis (IPF) lung samples confirmed expression of ARG1 in myeloid cells, and arginase inhibition suppressed collagen expression in cultured precision-cut IPF lung slices. Taken together, we define a circuit between macrophages and fibroblasts that facilitates cross-feeding metabolism necessary for injury-associated fibrosis.

11.
Int J Med Inform ; 191: 105555, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39089210

RESUMEN

OBJECTIVE: Symptoms are significant kind of phenotypes for managing and controlling of the burst of acute infectious diseases, such as COVID-19. Although patterns of symptom clusters and time series have been considered the high potential prediction factors for the prognosis of patients, the elaborated subtypes and their progression patterns based on symptom phenotypes related to the prognosis of COVID-19 patients still need be detected. This study aims to investigate patient subtypes and their progression patterns with distinct features of outcome and prognosis. METHODS: This study included a total of 14,139 longitudinal electronic medical records (EMRs) obtained from four hospitals in Hubei Province, China, involving 2,683 individuals in the early stage of COVID-19 pandemic. A deep representation learning model was developed to help acquire the symptom profiles of patients. K-means clustering algorithm is used to divide them into distinct subtypes. Subsequently, symptom progression patterns were identified by considering the subtypes associated with patients upon admission and discharge. Furthermore, we used Fisher's test to identify significant clinical entities for each subtype. RESULTS: Three distinct patient subtypes exhibiting specific symptoms and prognosis have been identified. Particularly, Subtype 0 includes 44.2% of the whole and is characterized by poor appetite, fatigue and sleep disorders; Subtype 1 includes 25.6% cases and is characterized by confusion, cough with bloody sputum, encopresis and urinary incontinence; Subtype 2 includes 30.2% cases and is characterized by dry cough and rhinorrhea. These three subtypes demonstrate significant disparities in prognosis, with the mortality rates of 4.72%, 8.59%, and 0.25% respectively. Furthermore, symptom cluster progression patterns showed that patients with Subtype 0 who manifest dark yellow urine, chest pain, etc. in the admission stage exhibit an elevated risk of transforming into the more severe subtypes with poor outcome, whereas those presenting with nausea and vomiting tend to incline towards entering the milder subtype. CONCLUSION: This study has proposed a clinical meaningful approach by utilizing the deep representation learning and real-world EMR data containing symptom phenotypes to identify the COVID-19 subtypes and their progression patterns. The results would be potentially useful to help improve the precise stratification and management of acute infectious diseases.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Progresión de la Enfermedad , Registros Electrónicos de Salud , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/diagnóstico , Registros Electrónicos de Salud/estadística & datos numéricos , Pronóstico , Femenino , Masculino , Persona de Mediana Edad , China/epidemiología , Adulto , Anciano
12.
Res Sq ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39184105

RESUMEN

Single-cell transcriptomics is valuable for uncovering individual cell properties, particularly in highly heterogeneous systems. However, this technique often results in the analysis of many well-characterized cells, increasing costs and diluting rare cell populations. To address this, we developed PURE-seq (PIP-seq for Rare-cell Enrichment and Sequencing) for scalable sequencing of rare cells. PURE-seq allows direct cell loading from FACS into PIP-seq reactions, minimizing handling and reducing cell loss. PURE-seq reliably captures rare cells, with 60 minutes of sorting capturing tens of cells at a rarity of 1 in 1,000,000. Using PURE-seq, we investigated murine long-term hematopoietic stem cells and their transcriptomes in the context of hematopoietic aging, identifying Egr1 as a potential master regulator of hematopoiesis in the aging context. PURE-seq offers an accessible and reliable method for isolating and sequencing cells that are currently too rare to capture successfully with existing methods.

13.
Int J Mol Sci ; 25(16)2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39201722

RESUMEN

Polycystic ovary syndrome (PCOS) is a prevalent metabolic disorder among women of reproductive age, characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovaries. The pathogenesis of PCOS involves a complex interplay of genetic and environmental factors, including insulin resistance (IR) and resultant hyperinsulinemia. Insulin receptors, primarily in skeletal muscle, liver, and adipose tissue, activate downstream signaling pathways like PI3K-AKT and MAPK-ERK upon binding. These pathways regulate glucose uptake, storage, and lipid metabolism. Genome-wide association studies (GWASs) have identified several candidate genes related to steroidogenesis and insulin signaling. Environmental factors such as endocrine-disrupting chemicals and lifestyle choices also exacerbate PCOS traits. Other than lifestyle modification and surgical intervention, management strategies for PCOS can be achieved by using pharmacological treatments like antiandrogens, metformin, thiazolidinediones, aromatase inhibitor, and ovulation drugs to improve insulin sensitivity and ovulatory function, as well as combined oral contraceptives with or without cyproterone to resume menstrual regularity. Despite the complex pathophysiology and significant economic burden of PCOS, a comprehensive understanding of its molecular and cellular mechanisms is crucial for developing effective public health policies and treatment strategies. Nevertheless, many unknown aspects of PCOS, including detailed mechanisms of actions, along with the safety and effectiveness for the treatment, warrant further investigation.


Asunto(s)
Resistencia a la Insulina , Síndrome del Ovario Poliquístico , Síndrome del Ovario Poliquístico/terapia , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/etiología , Humanos , Femenino , Transducción de Señal/efectos de los fármacos , Animales
15.
Clin Otolaryngol ; 49(6): 785-792, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39115223

RESUMEN

BACKGROUND: This study was designed to evaluate the diagnostic efficacy of the minimum fascia-tumour distance (MFTD) in distinguishing deep-lobe benign parotid tumours from superficial-lobe tumours through both an original study and a meta-analysis. METHODS: In this study, we performed a retrospective analysis of data from 91 patients who had been diagnosed with benign parotid tumours. The MFTD values were sourced from preoperative ultrasound examinations. The locations of these tumours were confirmed through surgical findings. We assessed the diagnostic accuracy of MFTD by utilising receiver operating characteristic (ROC) curves. Additionally, we conducted a systematic review of the pertinent literature and performed a diagnostic meta-analysis to ascertain the overall diagnostic efficacy of MFTD in identifying benign parotid tumours. RESULTS: Patients with tumours in the deep lobe had a significantly greater MFTD than patients with tumours in the superficial lobe. Using a cutoff value of 3.50 mm for MFTD, we found an AUC of 0.93, a sensitivity of 81.8%, and a specificity of 98.8%. Our meta-analysis included seven studies covering a total of 1689 tumours. The pooled values for sensitivity, specificity, and diagnostic odds ratio (OR) of MFTD were 81.0%, 89.0%, and 32.2, respectively. The AUC of the summarised ROC curve of MFTD was 0.90. CONCLUSION: The MFTD demonstrated reliable diagnostic accuracy in identifying deep-lobe benign parotid tumours and may be incorporated into standard evaluations before parotidectomy.


Asunto(s)
Neoplasias de la Parótida , Humanos , Neoplasias de la Parótida/diagnóstico por imagen , Neoplasias de la Parótida/patología , Neoplasias de la Parótida/diagnóstico , Neoplasias de la Parótida/cirugía , Estudios Retrospectivos , Femenino , Masculino , Diagnóstico Diferencial , Persona de Mediana Edad , Adulto , Fascia/diagnóstico por imagen , Fascia/patología , Curva ROC , Anciano , Ultrasonografía , Glándula Parótida/diagnóstico por imagen , Glándula Parótida/cirugía , Glándula Parótida/patología
16.
Artículo en Inglés | MEDLINE | ID: mdl-39209206

RESUMEN

BACKGROUND & AIMS: A functional cure is an essential endpoint in the management of patients with chronic hepatitis B virus (HBV) infection. We evaluated the cumulative probability and predictors of functional cure in patients with chronic HBV infection after hepatitis B e antigen (HBeAg) seroconversion. METHODS: We retrospectively analyzed 413 (249 males and 164 females) initially HBeAg-positive chronic HBV-infected patients who were followed up for a mean of 26.36 ± 0.53 years. All underwent HBeAg seroconversion during follow-up. A functional cure was defined as durable HBsAg and HBV DNA loss without antiviral treatment for more than 24 weeks. RESULTS: After 10,888 person-years of follow-up, the cumulative probability of functional cure was 14.53% (n = 60). There were 24 (40%) subjects with functional cure after antiviral therapy. The annual functional cure rate was 0.55% per person-year, and increased to 0.96% per person-year after HBeAg seroconversion. In subjects with functional cure, the HBsAg and HBV DNA titers after HBeAg seroconversion were positively correlated with the time to functional cure (P < .001 and < .001, respectively). Multivariate Cox proportional hazards analysis of the cohort revealed that HBeAg seroconversion at <18 years of age, high-genetic-barrier nucleos(t)ide analogue(s) therapy before HBeAg seroconversion, and a serum HBsAg titer <1000 IU/mL at 18 months after HBeAg seroconversion were significant predictors of functional cure (P < .001, .001, and .001, respectively). CONCLUSIONS: In a cohort of chronic HBV-infected patients with long-term follow-up, HBeAg seroconversion in childhood, high-genetic-barrier nucleos(t)ide analogue(s) therapy, and low HBsAg titers after HBeAg seroconversion were significant predictors of functional cure.

17.
Phys Rev Lett ; 133(3): 036204, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39094154

RESUMEN

Solving the Hamiltonian of a system yields the energy dispersion and eigenstates. The geometric phase of the eigenstates generates many novel effects and potential applications. However, the geometric properties of the energy dispersion go unheeded. Here, we provide geometric insight into energy dispersion and introduce a geometric amplitude, namely, the geometric density of states (GDOS) determined by the Riemann curvature of the constant-energy contour. The geometric amplitude should accompany various local responses, which are generally formulated by the real-space Green's function. Under the stationary phase approximation, the GDOS simplifies the Green's function into its ultimate form. In particular, the amplitude factor embodies the spinor phase information of the eigenstates, favoring the extraction of the spin texture for topological surface states under an in-plane magnetic field through spin-polarized STM measurements. This work opens a new avenue for exploring the geometric properties of electronic structures and excavates the unexplored potential of spin-polarized STM measurements to probe the spinor phase information of eigenstates from their amplitudes.

18.
Artículo en Inglés | MEDLINE | ID: mdl-39182723

RESUMEN

BACKGROUND: Intermittent theta burst stimulation (iTBS) of the dorsolateral prefrontal cortex (DLPFC) is widely applied as therapeutic intervention in mental health, however understanding of its mechanisms is still incomplete. Prior MRI studies have mainly used offline iTBS or short sequences in concurrent TMS-fMRI. This study investigated a full 600 stimuli iTBS protocol using interleaved TMS-fMRI in comparison with two control conditions in healthy subjects. METHODS: In a crossover design, 18 participants underwent three sessions of interleaved iTBS-fMRI: 1) left DLPFC at 40% resting motor threshold (rMT) intensity, 2) left DLPFC at 80% rMT intensity, and 3) left primary motor cortex (M1) at 80% rMT intensity. We compared immediate blood-oxygen-level-dependent (BOLD) responses during interleaved iTBS-fMRI across these conditions including correlations between individual fMRI BOLD activation and iTBS induced electric field (E-field) strength at the target sites. RESULTS: Whole-brain analysis showed increased activation in several regions following iTBS. Specifically, left DLPFC, as well as bilateral M1, anterior cingulate cortex, and insula showed increased activation during 80% rMT left DLPFC stimulation. Increased BOLD activity in the left DLPFC was not observed with 40% rMT left DLPFC stimulation nor left M1 80% rMT iTBS, whereas activation in other regions was found to overlap between conditions. Of note, BOLD activation and E-field intensities were only correlated for M1 stimulation, but not for the DLPFC conditions. CONCLUSIONS: The study showed dosage and target specific BOLD activation during interleaved TMS-fMRI with 600 stimuli iTBS in healthy subjects. Future studies may use our approach for demonstrating target engagement.

19.
Cell Death Dis ; 15(8): 599, 2024 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-39155279

RESUMEN

Oral squamous cell carcinoma (OSCC) is a prevalent cancer worldwide, exhibiting unique regional prevalence. Despite advancements in diagnostics and therapy, the 5-year survival rate for patients has seen limited improvement. A deeper understanding of OSCC pathogenesis, especially its molecular underpinnings, is essential for improving detection, prevention, and treatment. In this context, noncoding RNAs, such as circular RNAs (circRNAs), have gained recognition as crucial regulators and potential biomarkers in OSCC progression. Our study highlights the discovery of previously uncharacterized circRNAs, including a SNX5 gene-derived circRNA, circSNX5, through deep sequencing of OSCC patient tissue transcriptomes. We established circSNX5's tumor-specific expression and its strong correlation with patient survival using structure-specific and quantitative PCR analyses. In vitro and in vivo experiments underscored circSNX5 RNA's regulatory role in cancer growth and metastasis. Further, our omics profiling and functional assays revealed that ADAM10 is a critical effector in circSNX5-mediated cancer progression, with circSNX5 maintaining ADAM10 expression by sponging miR-323. This novel circRNA-miRNA-mRNA regulatory axis significantly contributes to oral cancer progression and malignancy. Moreover, we discovered that circSNX5 RNA is produced via noncanonical sequential back-splicing of pre-mRNA, a process negatively regulated by the RNA-binding protein STAU1. This finding adds a new dimension to our understanding of exonic circRNA biogenesis in the eukaryotic transcriptome. Collectively, our findings offer a detailed mechanistic dissection and functional interpretation of a novel circRNA, shedding light on the role of the noncoding transcriptome in cancer biology and potentially paving the way for innovative therapeutic strategies.


Asunto(s)
Neoplasias de la Boca , ARN Circular , Nexinas de Clasificación , Humanos , ARN Circular/genética , ARN Circular/metabolismo , Nexinas de Clasificación/metabolismo , Nexinas de Clasificación/genética , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Neoplasias de la Boca/metabolismo , Animales , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Proliferación Celular/genética , Ratones , Ratones Desnudos , MicroARNs/metabolismo , MicroARNs/genética , Masculino , Femenino , Proteína ADAM10/metabolismo , Proteína ADAM10/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo
20.
bioRxiv ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39185152

RESUMEN

Single-cell transcriptomics is valuable for uncovering individual cell properties, particularly in highly heterogeneous systems. However, this technique often results in the analysis of many well-characterized cells, increasing costs and diluting rare cell populations. To address this, we developed PURE-seq (PIP-seq for Rare-cell Enrichment and Sequencing) for scalable sequencing of rare cells. PURE-seq allows direct cell loading from FACS into PIP-seq reactions, minimizing handling and reducing cell loss. PURE-seq reliably captures rare cells, with 60 minutes of sorting capturing tens of cells at a rarity of 1 in 1,000,000. Using PURE-seq, we investigated murine long-term hematopoietic stem cells and their transcriptomes in the context of hematopoietic aging, identifying Egr1 as a potential master regulator of hematopoiesis in the aging context. PURE-seq offers an accessible and reliable method for isolating and sequencing cells that are currently too rare to capture successfully with existing methods.

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