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1.
Nature ; 603(7901): 434-438, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35296844

RESUMEN

Oxidation can deteriorate the properties of copper that are critical for its use, particularly in the semiconductor industry and electro-optics applications1-7. This has prompted numerous studies exploring copper oxidation and possible passivation strategies8. In situ observations have, for example, shown that oxidation involves stepped surfaces: Cu2O growth occurs on flat surfaces as a result of Cu adatoms detaching from steps and diffusing across terraces9-11. But even though this mechanism explains why single-crystalline copper is more resistant to oxidation than polycrystalline copper, the fact that flat copper surfaces can be free of oxidation has not been explored further. Here we report the fabrication of copper thin films that are semi-permanently oxidation resistant because they consist of flat surfaces with only occasional mono-atomic steps. First-principles calculations confirm that mono-atomic step edges are as impervious to oxygen as flat surfaces and that surface adsorption of O atoms is suppressed once an oxygen face-centred cubic (fcc) surface site coverage of 50% has been reached. These combined effects explain the exceptional oxidation resistance of ultraflat Cu surfaces.

2.
EMBO J ; 41(8): e109365, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35285539

RESUMEN

Tissue homeostasis requires lineage fidelity of stem cells. Dysregulation of cell fate specification and differentiation leads to various diseases, yet the cellular and molecular mechanisms governing these processes remain elusive. We demonstrate that YAP/TAZ activation reprograms airway secretory cells, which subsequently lose their cellular identity and acquire squamous alveolar type 1 (AT1) fate in the lung. This cell fate conversion is mediated via distinctive transitional cell states of damage-associated transient progenitors (DATPs), recently shown to emerge during injury repair in mouse and human lungs. We further describe a YAP/TAZ signaling cascade to be integral for the fate conversion of secretory cells into AT1 fate, by modulating mTORC1/ATF4-mediated amino acid metabolism in vivo. Importantly, we observed aberrant activation of the YAP/TAZ-mTORC1-ATF4 axis in the altered airway epithelium of bronchiolitis obliterans syndrome, including substantial emergence of DATPs and AT1 cells with severe pulmonary fibrosis. Genetic and pharmacologic inhibition of mTORC1 activity suppresses lineage alteration and subepithelial fibrosis driven by YAP/TAZ activation, proposing a potential therapeutic target for human fibrotic lung diseases.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas Señalizadoras YAP , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Aminoácidos Esenciales , Animales , Diferenciación Celular , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Ratones
3.
Nat Chem Biol ; 19(8): 972-980, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36894722

RESUMEN

Although several high-fidelity SpCas9 variants have been reported, it has been observed that this increased specificity is associated with reduced on-target activity, limiting the applications of the high-fidelity variants when efficient genome editing is required. Here, we developed an improved version of Sniper-Cas9, Sniper2L, which represents an exception to this trade-off trend as it showed higher specificity with retained high activity. We evaluated Sniper2L activities at a large number of target sequences and developed DeepSniper, a deep learning model that can predict the activity of Sniper2L. We also confirmed that Sniper2L can induce highly efficient and specific editing at a large number of target sequences when it is delivered as a ribonucleoprotein complex. Mechanically, the high specificity of Sniper2L originates from its superior ability to avoid unwinding a target DNA containing even a single mismatch. We envision that Sniper2L will be useful when efficient and specific genome editing is required.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , ADN/genética
4.
J Am Chem Soc ; 146(22): 15045-15052, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38768128

RESUMEN

Chiral Pb-free metal-halide semiconductors (MHSs) have attracted considerable attention in the field of spintronics due to various interesting spin-related properties and chiral-induced spin selectivity (CISS) effect. Despite their excellent chemical and structural tunability, the material scope and crystal structure of Pb-free chiral MHSs exhibiting the CISS effect are still limited; chiral MHSs that have metal-halide structures of octahedra and tetrahedra are only reported. Here, we report a new class of chiral MHSs, of which palladium (Pd)-halides are formed in 1D square-pyramidal structures or 0D square-planar structures, with a general formula of ((R/S-MBA)2PdBr4)1-x((R/S-MBA)2PdCl4)x (MBA = methylbenzylammonium; x = 0, 0.25, 0.5, 0.75, and 1) for the first time. The crystals adopt the 1D helical chain of Pd-halide square-pyramid (for x = 0, 0.25, 0.5, and 0.75) and 0D structure of Pd-halide square-plane (for x = 1). All the Pd-halides are distorted by the interaction between the halide and the chiral organic ammonium and arranged in a noncentrosymmetric position. Circular dichroism (CD) for ((R/S-MBA)2PdBr4)1-x((R/S-MBA)2PdCl4)x indicates that chirality was transferred from chiral organic ammonium to Pd-halide inorganics. ((R-MBA)2PdBr4)1-x((R-MBA)2PdCl4)x (x = 0, 0.25, 0.5, and 0.75) shows a distortion index of 0.127-0.128, which is the highest value among the previously reported chiral MHSs to the best of our knowledge. We also find that (R/S-MBA)2Pd(Br1-xClx)4 crystals grow along the out-of-plane direction during spin coating and have high c-axis orientation and crystallinity, and (R/S-MBA)2Pd(Br1-xClx)4 (x = 0 and 0.5) crystals exhibit a CISS effect in polycrystalline bulk films. These results demonstrate the possibility of a new metal-halide series with square-planar structures or square-pyramidal structures for future spintronic applications.

5.
BMC Med ; 22(1): 130, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38519982

RESUMEN

BACKGROUND: Comprehensive data on patients at high risk of sudden cardiac death (SCD) in emerging countries are lacking. The aim was to deepen our understanding of the SCD phenotype and identify risk factors for death among patients at high risk of SCD in emerging countries. METHODS: Patients who met the class I indication for implantable cardioverter-defibrillator (ICD) implantation according to guideline recommendations in 17 countries and regions underrepresented in previous trials were enrolled. Countries were stratified by the WHO regional classification. Patients were or were not implanted with an ICD at their discretion. The outcomes were all-cause mortality and SCD. RESULTS: We enrolled 4222 patients, and 3889 patients were included in the analysis. The mean follow-up period was 21.6 ± 10.2 months. There were 433 (11.1%) instances of all-cause mortality and 117 (3.0%) cases of SCD. All-cause mortality was highest in primary prevention (PP) patients from Southeast Asia and secondary prevention (SP) patients from the Middle East and Africa. The SCD rates among PP and SP patients were both highest in South Asia. Multivariate Cox regression modelling demonstrated that in addition to the independent predictors identified in previous studies, both geographic region and ICD use were associated with all-cause mortality in patients with high SCD risk. Primary prophylactic ICD implantation was associated with a 36% (HR = 0.64, 95% CI 0.531-0.802, p < 0.0001) lower all-cause mortality risk and an 80% (HR = 0.20, 95% CI = 0.116-0.343, p < 0.0001) lower SCD risk. CONCLUSIONS: There was significant heterogeneity among patients with high SCD risk in emerging countries. The influences of geographic regions on patient characteristics and outcomes were significant. Improvement in increasing ICD utilization and uptake of guideline-directed medical therapy in emerging countries is urgent. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02099721.


Asunto(s)
Desfibriladores Implantables , Humanos , Factores de Riesgo , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/prevención & control , África , Medio Oriente
6.
Cardiovasc Diabetol ; 23(1): 46, 2024 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-38281993

RESUMEN

BACKGROUND: Underweight imposes significant burden on cardiovascular outcomes in patients with diabetes mellitus. However, less is known about the impact of serial change in body weight status measured as body mass index (BMI) on the risk of sudden cardiac arrest (SCA). This study investigated the association between SCA and temporal change in BMI among patients with diabetes mellitus. METHODS: Based on Korean National Health Insurance Service database, participants with diabetes mellitus who underwent health examination between 2009 and 2012 and had prior health examination data (four years ago, 2005-2008) were retrospectively analyzed. BMI was measured at baseline (2005-2008) and 4-year follow-up health examination (2009-2012). Patients were classified in four groups according to the body weight status and its temporal change: sustained non-underweight, sustained underweight, previous underweight, and newly developed underweight. Primary outcome was defined as occurrence of SCA. RESULTS: A total of 1,355,746 patients with diabetes mellitus were included for analysis, and SCA occurred in 12,554 cases. SCA was most common in newly developed underweight (incidence rate = 4.45 per 1,000 person-years), followed by sustained underweight (incidence rate = 3.90), previous underweight (incidence rate = 3.03), and sustained non-underweight (incidence rate = 1.34). Adjustment of covariates resulted highest risk of SCA in sustained underweight (adjusted hazard ratio = 2.60, 95% confidence interval [2.25-3.00], sustained non-underweight as a reference), followed by newly developed underweight (2.42, [2.15-2.74]), and previous underweight (2.12, [1.77-2.53]). CONCLUSIONS: In diabetes mellitus, sustained underweight as well as decrease in body weight during 4-year follow-up imposes substantial risk on SCA. Recovery from underweight over time had relatively lower, but yet increased risk of SCA. Both underweight and dynamic decrease in BMI can be associated with increased risk of SCA.


Asunto(s)
Diabetes Mellitus , Delgadez , Humanos , Índice de Masa Corporal , Factores de Riesgo , Estudios Retrospectivos , Delgadez/diagnóstico , Delgadez/epidemiología , Pronóstico , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Peso Corporal , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/etiología
7.
Eur Radiol ; 34(3): 2036-2047, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37656175

RESUMEN

OBJECTIVES: CT reconstruction algorithms affect radiomics reproducibility. In this study, we evaluate the effect of deep learning-based image conversion on CT reconstruction algorithms. METHODS: This study included 78 hepatocellular carcinoma (HCC) patients who underwent four-phase liver CTs comprising non-contrast, late arterial (LAP), portal venous (PVP), and delayed phase (DP), reconstructed using both filtered back projection (FBP) and advanced modeled iterative reconstruction (ADMIRE). PVP images were used to train a convolutional neural network (CNN) model to convert images from FBP to ADMIRE and vice versa. LAP, PVP, and DP images were used for validation and testing. Radiomic features were extracted for each patient with a semi-automatic segmentation tool. We used concordance correlation coefficients (CCCs) to evaluate the radiomics reproducibility for original FBP (oFBP) vs. original ADMIRE (oADMIRE), oFBP vs. converted FBP (cFBP), and oADMIRE vs. converted ADMIRE (cADMIRE). RESULTS: In the test group including 30 patients, the CCC and proportion of reproducible features (CCC ≥ 0.85) for oFBP vs. oADMIRE were 0.65 and 32.9% (524/1595) for LAP, 0.65 and 35.9% (573/1595) for PVP, and 0.69 and 43.8% (699/1595) for DP. For oFBP vs. cFBP, the values increased to 0.92 and 83.9% (1339/1595) for LAP, 0.89 and 71.0% (1133/1595) for PVP, and 0.90 and 79.7% (1271/1595) for DP. Similarly, for oADMIRE vs. cADMIRE, the values increased to 0.87 and 68.1% (1086/1595) for LAP, 0.91 and 82.1% (1309/1595) for PVP, and 0.89 and 76.2% (1216/1595) for DP. CONCLUSIONS: CNN-based image conversion between CT reconstruction algorithms improved the radiomics reproducibility of HCCs. CLINICAL RELEVANCE STATEMENT: This study demonstrates that using a CNN-based image conversion technique significantly improves the reproducibility of radiomic features in HCCs, highlighting its potential for enhancing radiomics research in HCC patients. KEY POINTS: Radiomics reproducibility of HCC was improved via CNN-based image conversion between two different CT reconstruction algorithms. This is the first clinical study to demonstrate improvements across a range of radiomic features in HCC patients. This study promotes the reproducibility and generalizability of different CT reconstruction algorithms in radiomics research.


Asunto(s)
Carcinoma Hepatocelular , Aprendizaje Profundo , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Reproducibilidad de los Resultados , Radiómica , Neoplasias Hepáticas/diagnóstico por imagen , Algoritmos , Tomografía Computarizada por Rayos X/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos
8.
Europace ; 26(4)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38587017

RESUMEN

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , América Latina , Resultado del Tratamiento , Catéteres , Asia , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos
9.
Gastric Cancer ; 27(2): 221-234, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38212543

RESUMEN

BACKGROUND: Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) has been reported to account for approximately 5-16% of all GCs with good prognosis compared to EBV-negative GC. We evaluated the clinicopathological characteristics of EBVaGC including survival rate in South Korea. METHODS: A total of 4,587 patients with GC who underwent EBV in situ hybridization (EBV-ISH) were prospectively enrolled at the Seoul National University Bundang Hospital from 2003 to 2021. Age, sex, smoking status, cancer type and stage, tumor size and location, histological type, molecular features and survival information were analyzed. RESULTS: A total of 456 patients with GC (9.9%) were positive for EBV. The EBVaGC group displayed a higher proportion of males (P < 0.001), a predominant presence in the proximal stomach (P < 0.001), a higher proportion of undifferentiated cancer (P < 0.001), and a lower cancer stage (P = 0.004) than the EBV-negative group. Cox multivariate analyses revealed age (hazard ratio [HR] = 1.025, P < 0.001), tumor size (HR = 1.109, P < 0.001), and cancer stage (stage2 HR = 4.761, P < 0.001; stage3 HR = 13.286, P < 0.001; stage4 HR = 42.528, P < 0.001) as significant risk factors for GC-specific mortality, whereas EBV positivity was inversely correlated (HR = 0.620, P = 0.022). Furthermore, the EBVaGC group displayed statistically significant survival advantages over the EBV-negative cancer group in terms of both overall (P = 0.021) and GC-specific survival (P = 0.007) on the Kaplan-Meier survival curve. However, this effect was evident only in males. CONCLUSIONS: EBVaGC patients showed better prognoses despite their association with proximal location and poorly differentiated histology in male, probably due to the difference in immunity between males and females.


Asunto(s)
Carcinoma , Infecciones por Virus de Epstein-Barr , Neoplasias Gástricas , Femenino , Humanos , Masculino , Neoplasias Gástricas/patología , Herpesvirus Humano 4 , Pronóstico , Carcinoma/complicaciones
10.
Biologicals ; 86: 101768, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38733709

RESUMEN

Plasma-derived medicinal products (PDMPs) are essential in the treatment of acute and chronic life-threatening diseases. The Korea Ministry of Food and Drug Safety has conducted a national lot release (NLR) of PDMPs since 2012 based on a summary protocol review system and lot release testing. However, few studies have investigated the performance or characteristics of the NLR framework. Over the past decade, the NLR of PDMPs was approximately 1000 per year, including mainly albumins, immunoglobulins, fibrin sealant kits, and coagulation factors, among others. The NLR system for PDMPs is similar to that for vaccines, except that PDMPs are manufactured using human plasma, which requires strict safety management. This study describes the status of NLR procedures for PDMPs and outlines the regulatory requirements needed to safely manage plasma for fractionation in Korea. This study can aid national control laboratories and marketing authorization holders in developing regulatory systems that assure the availability of safe and effective PDMPs.


Asunto(s)
Plasma , República de Corea , Humanos , Plasma/química
11.
BMC Public Health ; 24(1): 413, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38331734

RESUMEN

BACKGROUND: Previous studies have predominantly focused on smartphone overdependence among adolescents and young adults. However, as smartphone usage has recently surged among South Korean middle-aged and older adults, the risk of smartphone overdependence cannot be overlooked among this population. Therefore, this study was conducted to examine the smartphone usage pattern and the associated risk of overdependence in this specific age group. METHODS: The data for individuals who aged 50 or older were extracted from the dataset of a nationwide survey, "The Survey on Smartphone Overdependence, 2021," and the usage of each type of smartphone content and risk of smartphone overdependence among individuals in their 50 s and 60 s were investigated. Age-group-based differences in demographic characteristics, Smartphone Overdependence Scale scores, self-awareness of smartphone overdependence, digital literacy, and psychosocial factors were analyzed. Additionally, a multivariable logistic regression analysis was conducted to explore the factors associated with the potential-to-high risk of smartphone overdependence in both age groups. RESULTS: Individuals in their 50s had significantly higher digital literacy, social relations, life satisfaction, and smartphone overdependence scores than those in their 60s, and the percentage of individuals in the high-risk group was also higher in the 50s age group. For both age groups, the most used content was "messenger," "news," and "movies/TV/videos," whereas the least used content was e-learning, gambling, and adult content. The multivariable analysis indicated that, for individuals in their 50s, having a lower educational level was associated with significantly higher odds, whereas having a job and utilizing e-commerce-related contents on smartphone were associated with significantly lower odds of potential-to-high risk for smartphone overdependence. Concerning individuals in their 60s, having a lower educational level and using adult content or gambling were significantly associated with higher odds of potential-to-high risk for smartphone overdependence. CONCLUSION: This study reveals the risk of smartphone overdependence among middle-aged and older adults in South Korea as well as the associated risk factors. This will assist policymakers in developing policies for the appropriate use of smartphones by these age groups.


Asunto(s)
Teléfono Inteligente , Persona de Mediana Edad , Adulto Joven , Adolescente , Humanos , Anciano , Estudios Transversales , Encuestas y Cuestionarios , República de Corea/epidemiología
12.
Eur Spine J ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38955867

RESUMEN

PURPOSE: Spinal tuberculosis, if not promptly treated, can lead to kyphotic deformity, causing persistent neurological abnormalities and discomfort. Spinal cord compression can occur due to ossification of the ligamentum flavum (OLF) at the apex of kyphosis. Traditional surgical interventions, including osteotomy and fixation, pose challenges and risks. We present a case of thoracic myelopathy in a patient with post-tuberculosis kyphosis, successfully treated with biportal endoscopic spinal surgery (BESS). METHOD: A 73-year-old female with a history of untreated kyphosis presented with walking difficulties and lower limb pain. Imaging revealed a kyphotic deformity of 120° and OLF-induced cord compression at T8-9. UBE was performed under spinal anesthesia. Using the BESS technique, OLF was successfully removed with minimal damage to the stabilizing structures. RESULTS: The patient exhibited neurological improvement after surgery, walking on the first day without gait instability. Follow-up at 1 year showed no kyphosis progression or recurrence of symptoms. BESS successfully resolved the cord compression lesion with minimal blood loss and damage. CONCLUSION: In spinal tuberculosis-related OLF, conventional open surgery poses challenges. BESS emerges as an excellent alternative, providing effective decompression with reduced instrumentation needs, minimal blood loss, and preservation of surrounding structures. Careful patient selection and surgical planning are crucial for optimal outcomes in endoscopic procedures.

13.
Eur Spine J ; 33(1): 324-331, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37558910

RESUMEN

PURPOSE: Adjacent segment disease (ASD) is a common complication in fusion surgery. In the event of solid segmental fusion, previous implants can be removed or preserved during fusion extension for ASD. To compare the surgical outcomes of patients with and without implants and analyzes the risk factors for postoperative mechanical complications. METHODS: Patients who underwent fusion extension for lumbar ASD from 2011 to 2019 with a minimum 2 year follow-up were retrospectively reviewed. Spinopelvic parameters were measured preoperatively and postoperatively. Clinical outcomes and surgical complications were compared between groups with implants preserved and removed. Risk factors for mechanical complications, including clinical, surgical, and radiographic factors were analyzed. RESULTS: Sixty-nine patients (mean age, 69.9 ± 6.9 years) were included. The mean numbers of initial and extended fused segments were 2.8 ± 0.7 and 2.7 ± 0.7, respectively. Previous implants were removed in 43 patients (R group) and preserved in 26 patients (P group). Both groups showed an improvement in clinical outcomes without between-group differences. The operation time was significantly longer in R group (260 vs 207 min, p < 0.001). Mechanical complications occurred in 13 patients (12 in R group and 1 in P group) and reoperation was needed in 3 patients (R group). Implant removal, index fusion surgery including L5-S1, and postoperative sagittal malalignment were risk factors for mechanical complications. CONCLUSION: Implant removal was a risk factor for mechanical complications. Index fusion surgery including L5-S1 and postoperative sagittal malalignment were also risk factors for mechanical complications.


Asunto(s)
Complicaciones Posoperatorias , Fusión Vertebral , Humanos , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Prótesis e Implantes , Reoperación , Factores de Riesgo , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Fusión Vertebral/efectos adversos
14.
Eur Spine J ; 33(1): 61-67, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37294358

RESUMEN

PURPOSE: The purpose of this study was to investigate autophagy in an extruded disc and to compare this activity with the activity in the remaining disc after lumbar disc herniation in the same patient. METHODS: In total, 12 patients (females 4, males 8) with the extruded type of lumbar disc herniation (LDH) were surgically treated. Their mean age was 54.3 ± 15.8 years (range: 29 ~ 78 years). The mean interval from the occurrence of symptoms to the operation was 9.8 ± 9.4 weeks (range: 2 ~ 24 weeks). The extruded discs were excised, and the remaining disc material removed, to prevent recurrence of herniation. Immediately after specimen collection, all tissues were stored at -70 °C prior to analysis. Autophagy was assessed immunohistochemically and via Western blotting for Atg5, Atg7, Atg12, Atg12L1, and Beclin-1. And the relationship between autophagy and apoptosis was investigated by correlation analysis of caspase-3 with autophagy proteins. RESULTS: The expression levels of autophagic markers were significantly increased in the extruded discs compared to the remaining discs within the same patients. The mean expression levels of Atg5, Atg7, Atg12, and Beclin-1 in extruded discs were statistically significantly higher than those in the remaining discs (P < 0.01, P < 0.001, P < 0.01, and P < 0.001 respectively). CONCLUSIONS: The autophagic pathway was more active in extruded disc material than in remaining disc material within the same patient. This may explain spontaneous resorption of the extruded disc after LDH.


Asunto(s)
Desplazamiento del Disco Intervertebral , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Desplazamiento del Disco Intervertebral/cirugía , Beclina-1 , Vértebras Lumbares/cirugía , Discectomía , Autofagia
15.
Acta Neurochir (Wien) ; 166(1): 143, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38509395

RESUMEN

BACKGROUND: To investigate the incidence and risk factors of coronal vertical vertebral body fracture (CV-VBF) during lateral lumbar interbody fusion (LLIF) for degenerative lumbar disease. METHODS: Clinical data, including age, sex, body mass index, and bone mineral density, were reviewed. Radiological assessments, such as facet joint arthrosis, intervertebral disc motion, index disc height, and cage profiles, were conducted. Posterior instrumentation was performed using either a single or staged procedure after LLIF. Demographic and surgical data were compared between patients with and without VBF. RESULTS: Out of 273 patients (552 levels), 7 (2.6%) experienced CV-VBF. Among the 552 levels, VBF occured in 7 levels (1.3%). All VBF cases developed intraoperatively during LLIF, with no instances caused by cage subsidence during the follow-up period. Sagittal motion in segments adjacent to VBF was smaller than in others (4.6° ± 2.6° versus 6.5° ± 3.9°, P = 0.031). The average grade of facet arthrosis was 2.5 ± 0.7, indicating severe facet arthrosis. All fractures developed due to oblique placement of a trial or cage into the index disc space, leading to a nutcracker effect. These factors were not related to bone quality. CONCLUSIONS: CV-VBF after LLIF occurred in 2.6% of patients, accounting for 1.3% of all LLIF levels. A potential risk factor for VBF involves the nutcracker-impinging effect due to the oblique placement of a cage. Thorough preoperative evaluations and surgical procedures are needed to avoid VBF when considering LLIF in patients with less mobile spine.


Asunto(s)
Osteoartritis , Fracturas Craneales , Fusión Vertebral , Humanos , Cuerpo Vertebral , Estudios Retrospectivos , Factores de Riesgo , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Osteoartritis/etiología , Resultado del Tratamiento
16.
Medicina (Kaunas) ; 60(6)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38929563

RESUMEN

Background: Teriparatide is an anabolic agent for osteoporosis and is believed to improve the bone healing process. Previous studies showed that teriparatide could enhance not only fracture healing but also spine fusion. It has been reported that use of teriparatide could promote the spine fusion process and decrease mechanical complications. However, there was no consensus regarding optimal treatment duration. The purpose of this study was to compare surgical outcomes between short-duration and long-duration teriparatide treatment after lumbar fusion surgery in elderly patients. Materials and Methods: All consecutive patients older than 60 years who underwent 1-level lumbar fusion surgery for degenerative diseases between January 2015 and December 2019 were retrospectively reviewed. Based on the duration of teriparatide treatment (daily subcutaneous injection of 20 µg teriparatide), patients were subdivided into two groups: a short-duration (SD) group (<6 months) and a long-duration (LD) group (≥6 months). Mechanical complications, such as screw loosening, cage subsidence, and adjacent vertebral fractures, were investigated. Postoperative 1-year union rate was also evaluated on computed tomography. Clinical outcomes were recorded using visual analog scale (VAS) and Oswestry Disability Index (ODI). Between-group differences for these radiographic and clinical outcomes were analyzed. Results: Ninety-one patients were reviewed in this study, including sixty patients in the SD group and thirty-one patients in the LD group. Their mean age was 72.3 ± 6.2 years, and 79 patients were female. Mean T-score was -3.3 ± 0.8. Cage subsidence (6.7% vs. 3.2%), screw loosening (28.3% vs. 35.5%), and adjacent vertebral fracture (6.7% vs. 9.7%) were not significantly different between the SD and LD groups. Union rate at 1-year postoperative was 65.0% in the SD group and 87.1% in the LD group (p = 0.028). Both groups showed improvement in VAS and ODI after surgery. However, the differences of VAS from preoperative to 6 months and 1 year postoperative were significantly higher in the LD group. Conclusions: Longer teriparatide treatment after lumbar fusion surgery resulted in a higher union rate at 1-year postoperative than the shorter treatment. Also, it could be more beneficial for clinical outcomes.


Asunto(s)
Fusión Vertebral , Teriparatido , Humanos , Teriparatido/uso terapéutico , Teriparatido/administración & dosificación , Femenino , Masculino , Fusión Vertebral/métodos , Anciano , Estudios Retrospectivos , Resultado del Tratamiento , Conservadores de la Densidad Ósea/uso terapéutico , Conservadores de la Densidad Ósea/administración & dosificación , Vértebras Lumbares/cirugía , Anciano de 80 o más Años , Factores de Tiempo , Persona de Mediana Edad
17.
Circulation ; 145(25): 1839-1849, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35507499

RESUMEN

BACKGROUND: Catheter ablation as first-line therapy for ventricular tachycardia (VT) at the time of implantable cardioverter defibrillator (ICD) implantation has not been adopted into clinical guidelines. Also, there is an unmet clinical need to prospectively examine the role of VT ablation in patients with nonischemic cardiomyopathy, an increasingly prevalent population that is referred for advanced therapies globally. METHODS: We conducted an international, multicenter, randomized controlled trial enrolling 180 patients with cardiomyopathy and monomorphic VT with an indication for ICD implantation to assess the role of early, first-line ablation therapy. A total of 121 patients were randomly assigned (1:1) to ablation plus an ICD versus conventional medical therapy plus an ICD. Patients who refused ICD (n=47) were followed in a prospective registry after stand-alone ablation treatment. The primary outcome was a composite end point of VT recurrence, cardiovascular hospitalization, or death. RESULTS: Randomly assigned patients had a mean age of 55 years (interquartile range, 46-64) and left ventricular ejection fraction of 40% (interquartile range, 30%-49%); 81% were male. The underlying heart disease was ischemic cardiomyopathy in 35%, nonischemic cardiomyopathy in 30%, and arrhythmogenic cardiomyopathy in 35%. Ablation was performed a median of 2 days before ICD implantation (interquartile range, 5 days before to 14 days after). At 31 months, the primary outcome occurred in 49.3% of the ablation group and 65.5% in the control group (hazard ratio, 0.58 [95% CI, 0.35-0.96]; P=0.04). The observed difference was driven by a reduction in VT recurrence in the ablation arm (hazard ratio, 0.51 [95%CI, 0.29-0.90]; P=0.02). A statistically significant reduction in both ICD shocks (10.0% versus 24.6%; P=0.03) and antitachycardia pacing (16.2% versus 32.8%; P=0.04) was observed in patients who underwent ablation compared with control. No differences in cardiovascular hospitalization (32.0% versus. 33.7%; hazard ratio, 0.82 [95% CI, 0.43-1.56]; P=0.55) or mortality (8.9% versus 8.8%; hazard ratio, 1.40 [95% CI, 0.38-5.22]; P=0.62]) were observed. Ablation-related complications occurred in 8.3% of patients. CONCLUSIONS: Among patients with cardiomyopathy of varied causes, early catheter ablation performed at the time of ICD implantation significantly reduced the composite primary outcome of VT recurrence, cardiovascular hospitalization, or death. These findings were driven by a reduction in ICD therapies. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02848781.


Asunto(s)
Cardiomiopatías , Ablación por Catéter , Desfibriladores Implantables , Taquicardia Ventricular , Cardiomiopatías/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Volumen Sistólico , Taquicardia Ventricular/cirugía , Resultado del Tratamiento , Función Ventricular Izquierda
18.
EMBO J ; 38(24): e101196, 2019 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-31750563

RESUMEN

Parkinson's disease (PD) is neurodegenerative movement disorder characterized by degeneration of midbrain-type dopamine (mDA) neurons in the substantia nigra (SN). The RNA-binding protein Lin28 plays a role in neuronal stem cell development and neuronal differentiation. In this study, we reveal that Lin28 conditional knockout (cKO) mice show degeneration of mDA neurons in the SN, as well as PD-related behavioral deficits. We identify a loss-of-function variant of LIN28A (R192G substitution) in two early-onset PD patients. Using an isogenic human embryonic stem cell (hESC)/human induced pluripotent stem cell (hiPSC)-based disease model, we find that the Lin28 R192G variant leads to developmental defects and PD-related phenotypes in mDA neuronal cells that can be rescued by expression of wild-type Lin28A. Cell transplantation experiments in PD model rats show that correction of the LIN28A variant in the donor patient (pt)-hiPSCs leads to improved behavioral phenotypes. Our data link LIN28A to PD pathogenesis and suggest future personalized medicine targeting this variant in patients.


Asunto(s)
Enfermedad de Parkinson/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/fisiología , Sustancia Negra/metabolismo , Animales , Conducta Animal , Trasplante de Células , Modelos Animales de Enfermedad , Dopamina/metabolismo , Neuronas Dopaminérgicas/fisiología , Células Madre Embrionarias/fisiología , Edición Génica , Predisposición Genética a la Enfermedad , Humanos , Células Madre Pluripotentes Inducidas/fisiología , Células Madre Pluripotentes Inducidas/trasplante , Ratones , Ratones Noqueados , Mutación , Células-Madre Neurales/fisiología , Células-Madre Neurales/trasplante , Enfermedad de Parkinson/genética , Ratas , Trasplante de Células Madre
19.
J Transl Med ; 21(1): 69, 2023 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-36732815

RESUMEN

BACKGROUND: Recurrence is common in glioblastoma multiforme (GBM) because of the infiltrative, residual cells in the tumor margin. Standard therapy for GBM consists of surgical resection followed by chemotherapy and radiotherapy, but the median survival of GBM patients remains poor (~ 1.5 years). For recurrent GBM, anti-angiogenic treatment is one of the common treatment approaches. However, current anti-angiogenic treatment modalities are not satisfactory because of the resistance to anti-angiogenic agents in some patients. Therefore, we sought to identify novel prognostic biomarkers that can predict the therapeutic response to anti-angiogenic agents in patients with recurrent glioblastoma. METHODS: We selected patients with recurrent GBM who were treated with anti-angiogenic agents and classified them into responders and non-responders to anti-angiogenic therapy. Then, we performed proteomic analysis using liquid-chromatography mass spectrometry (LC-MS) with formalin-fixed paraffin-embedded (FFPE) tissues obtained from surgical specimens. We conducted a gene-ontology (GO) analysis based on protein abundance in the responder and non-responder groups. Based on the LC-MS and GO analysis results, we identified potential predictive biomarkers for anti-angiogenic therapy and validated them in recurrent glioblastoma patients. RESULTS: In the mass spectrometry-based approach, 4957 unique proteins were quantified with high confidence across clinical parameters. Unsupervised clustering analysis highlighted distinct proteomic patterns (n = 269 proteins) between responders and non-responders. The GO term enrichment analysis revealed a cluster of genes related to immune cell-related pathways (e.g., TMEM173, FADD, CD99) in the responder group, whereas the non-responder group had a high expression of genes related to nuclear replisome (POLD) and damaged DNA binding (ERCC2). Immunohistochemistry of these biomarkers showed that the expression levels of TMEM173 and FADD were significantly associated with the overall survival and progression-free survival of patients with recurrent GBM. CONCLUSIONS: The candidate biomarkers identified in our protein analysis may be useful for predicting the clinical response to anti-angiogenic agents in patients with recurred GBM.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Proteómica , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Recurrencia Local de Neoplasia/genética , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Biomarcadores , Proteína de la Xerodermia Pigmentosa del Grupo D
20.
Am J Kidney Dis ; 82(3): 290-299.e1, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-36965829

RESUMEN

RATIONALE & OBJECTIVE: Metformin has been recommended for some patients with advanced chronic kidney disease. However, the value of metformin in kidney transplant recipients (KTRs) with pretransplant diabetes mellitus (DM) or posttransplant DM is uncertain. We investigated the clinical effects of metformin in KTRs. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: A total of 1,995 KTRs with diabetes from 6 tertiary referral centers in the Republic of Korea. EXPOSURE: Metformin usage was defined as the use of metformin for>90 days after kidney transplantation; 1,193 KTRs were metformin users, and 802 KTRs did not use metformin. Changing usage of metformin among those exposed for >90 days was also characterized. OUTCOME: Primary outcomes were all-cause mortality and death-censored graft failure (DCGF). Secondary outcomes were biopsy-proven acute rejection (BPAR) and lactic acidosis events. ANALYTICAL APPROACH: Survival analyses were conducted using multivariable Cox regression and competing risk analyses using Fine and Gray models. Changes in metformin use over time were modeled using a time-varying covariate. Metformin usage, mean daily dose, and hemoglobin A1c (HbA1c) changes were considered in the landmark analysis to address time-varying confounding. RESULTS: Metformin use was associated with a lower risk of DCGF (adjusted hazard ratio [AHR], 0.47 [95% CI, 0.23-0.96], P=0.038); there was no significant association with all-cause mortality (AHR, 0.94 [95% CI, 0.32-2.76], P=0.915) or BPAR (AHR 0.98 [95% CI, 0.62-1.54], P=0.942). In the subgroup analysis, metformin usage was associated with a reduced risk of all-cause mortality and a lower risk of DCGF for both pretransplantation DM and posttransplant DM groups. Metformin usage was associated with a lower risk of BPAR in the posttransplant DM group, although it was less effective in the pretransplantation DM group. There was no confirmed case of metformin-associated lactic acidosis (MALA) in the present cohort. A higher dose of metformin was correlated with lower risks of DCGF and BPAR. LIMITATIONS: Data on newer antidiabetic drugs such as SGLT2 inhibitors are limited, and there is potential limited generalizability to other populations. CONCLUSIONS: Metformin usage may benefit KTRs, as evidenced by its association with a reduced risk of DCGF and the absence of MALA events. Randomized controlled trials are needed to validate these observational findings.


Asunto(s)
Acidosis Láctica , Diabetes Mellitus , Trasplante de Riñón , Metformina , Humanos , Metformina/uso terapéutico , Estudios Retrospectivos , Receptores de Trasplantes , Factores de Riesgo
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