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1.
Bone Joint Res ; 13(9): 452-461, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39231531

RESUMO

Aims: The presence of facet tropism has been correlated with an elevated susceptibility to lumbar disc pathology. Our objective was to evaluate the impact of facet tropism on chronic lumbosacral discogenic pain through the analysis of clinical data and finite element modelling (FEM). Methods: Retrospective analysis was conducted on clinical data, with a specific focus on the spinal units displaying facet tropism, utilizing FEM analysis for motion simulation. We studied 318 intervertebral levels in 156 patients who had undergone provocation discography. Significant predictors of clinical findings were identified by univariate and multivariate analyses. Loading conditions were applied in FEM simulations to mimic biomechanical effects on intervertebral discs, focusing on maximal displacement and intradiscal pressures, gauged through alterations in disc morphology and physical stress. Results: A total of 144 discs were categorized as 'positive' and 174 discs as 'negative' by the results of provocation discography. The presence of defined facet tropism (OR 3.451, 95% CI 1.944 to 6.126) and higher Adams classification (OR 2.172, 95% CI 1.523 to 3.097) were important predictive parameters for discography-'positive' discs. FEM simulations showcased uneven stress distribution and significant disc displacement in tropism-affected discs, where loading exacerbated stress on facets with greater angles. During varied positions, notably increased stress and displacement were observed in discs with tropism compared to those with normal facet structure. Conclusion: Our findings indicate that facet tropism can contribute to disc herniation and changes in intradiscal pressure, potentially exacerbating disc degeneration due to altered force distribution and increased mechanical stress.

2.
Heliyon ; 10(18): e37871, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39315135

RESUMO

As hair dyeing gains popularity across all age groups, concerns about the potential damage caused by chemical treatments are also on the rise. Chemical dyes have a multifaceted impact on hair fibers, affecting their morphology, physical structure, and protein composition. In a comprehensive study, we investigated the alterations in morphological and mechanical properties, as well as the chemical composition of hair fibers following continuous dyeing. Our analysis employed various techniques, including atomic force microscopy (AFM), Fourier transform infrared (FT-IR) spectroscopy, and tensile strength measurements. To assess the cumulative damage resulting from repeated dyeing, we progressively increased the number of dyeing up to 10. Surprisingly, even a single dyeing session inflicted noticeable harm on the hair. However, the detrimental effects escalated significantly when hair underwent three or more consecutive dye treatments. While the mechanical properties and protein composition exhibited non-linear changes with increasing the number of dyeing, we observed that nanoscale damage to the cuticle surface intensified proportionally with the number of dyeing. These results highlight the critical need to consider the impacts of hair dyeing practices on both the health and the structural integrity of hair.

3.
J Vasc Surg ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39303864

RESUMO

OBJECTIVE: Although diabetes has been shown to be negatively associated with development of abdominal aortic aneurysm (AAA), patients with diabetes may still develop aneurysms. In this study we examined risk factors for development of AAA in patients with diabetes. METHODS: Adults over 50 years with diabetes who underwent health screening between 2009 and 2012 were followed for incident AAA until December 31, 2019. Cox proportional hazard regression models were used to calculate multivariate hazard ratios (HR) and 95% confidence intervals (CI) for risk factors associated with AAA. RESULTS: Among 1,913,066 participants (55.3% men), 6,996 AAA cases were identified during a mean follow-up of 7.7 years. Increased AAA risk was observed for age ≥ 65 years (HR 2.69, 95% CI 2.55-2.83), men (HR 1.81, 95% CI 1.69-1.94), smoking (ex-smoker ≥ 20 pack-years, HR 1.75, 95% CI 1.61-1.89; current smoker < 20 pack-years, HR 1.76, 95% CI 1.59-1.94; current smoker ≥ 20 pack-years, HR 2.40, 95% CI 2.23-2.59), abdominal obesity (HR 1.30, 95% CI 1.23-1.38), and comorbidities: hypertension (HR 1.63, 95% CI 1.53-1.73), dyslipidemia (HR 1.35, 95% CI 1.29-1.42), chronic kidney disease (HR 1.52, 95% CI 1.44-1.61), cardiovascular disease (HR 1.71, 95% CI 1.58-1.86). Heavy (HR 0.67, 95% CI 0.61-0.74) and mild alcohol consumption (HR 0.78, 95% CI 0.74-0.83), overweight (HR 0.87, 95% CI 0.81-0.93) and obesity (HR 0.81, 95% CI 0.75-0.87), longer diabetes duration (≥ 5 years: HR 0.74, 95% CI 0.70-0.78), and using ≥ 3 oral hypoglycemic agents (HR 0.84, 95% CI 0.79-0.90) were associated with decreased AAA risk, while insulin use was associated with a marginally increased risk (HR 1.09, 95% CI 1.00-1.18). Among the oral hypoglycemic agents, metformin (HR 0.95, 95% CI 0.90-1.00), thiazolidinedione (HR 0.87, 95% CI 0.79-0.97), and sulfonylurea (HR 0.88, 95% CI 0.83-0.93) were associated with decreased risk of AAA. CONCLUSIONS: Although diabetes is associated with decreased AAA risk, those with comorbid cardiometabolic diseases, abdominal obesity, and smoking history should be aware of increased AAA risk. Further studies are warranted to verify the potential use of oral hypoglycemic agents for reducing AAA risk.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39297854

RESUMO

BACKGROUND: Thrombus aspiration (TA) is used to decrease large thrombus burden (LTB), but it can cause distal embolization. OBJECTIVES: The aim of this study was to investigate the impact of TA failure on defective myocardial perfusion in patients with ST-segment elevation myocardial infarction (STEMI) and LTB. METHODS: In total, 812 consecutive patients with STEMI and LTB (thrombus grade ≥3) were enrolled, who underwent manual TA during the primary percutaneous coronary intervention. TA failure was defined as the absence of thrombus retrieval, presence of prestenting thrombus residue, or distal embolization. The final TIMI (Thrombolysis In Myocardial Infarction) flow grades and other myocardial perfusion parameters of the failed TA group were matched with those of the successful TA group. RESULTS: The proportion of final TIMI flow grade 3 was lower (74.6% vs 82.2%; P = 0.011) in the failed TA group (n = 279 [34.4%]) than in the successful TA group (n = 533 [65.6%]). The failed TA group also had lower myocardial blush grade, lower ST-segment resolution, and a higher incidence of microvascular obstruction than the successful TA group. TA failure was independently associated with low final TIMI flow grade (risk ratio: 1.525; 95% CI: 1.048-2.218; P = 0.027). Old age, Killip class ≥III, vessel tortuosity, calcification, and a culprit vessel other than the left anterior descending coronary artery were associated with TA failure. CONCLUSIONS: TA failure is associated with reduced myocardial perfusion in patients with STEMI and LTB. Advanced age, hemodynamic instability, hostile coronary anatomy such as tortuosity or calcification, and non-left anterior descending coronary artery status might attenuate TA performance. (Gangwon PCI Prospective Registry [GWPCI]; NCT02038127).

5.
Artigo em Inglês | MEDLINE | ID: mdl-39313241

RESUMO

Backgrounds/Aims: Minimally invasive pancreatoduodenectomy (MIPD), such as totally laparoscopic pancreatoduodenectomy (TLPD) or robot-assisted pancreatoduodenectomy (RAPD), is increasingly performed worldwide. This study aimed to compare the perioperative outcomes of TLPD and RAPD, and compare the oncologic outcomes between MIPD and open pancreatoduodenectomy (OPD) for malignant disease. Methods: This retrospective study was conducted at two hospitals that followed similar oncological surgical principles, including the extent of resection. RAPD was performed at Seoul National University Hospital, and TLPD at Seoul National University Bundang Hospital. Patient demographics, perioperative outcomes, and oncological outcomes were analyzed. Propensity score matching (PSM) analysis was performed to compare oncologic outcomes between MIPD and OPD. Results: Between 2015 and 2020, 332 RAPD and 178 TLPD were performed. The rates of Clavian-Dindo grade ≥ 3 complications (19.3% vs. 20.2%, p = 0.816), clinically relevant postoperative pancreatic fistula (9.9% vs. 11.8%, p = 0.647), and open conversions (6.6% vs. 10.5%, p = 0.163) were comparable between the two groups. The mean operation time (341 minutes vs. 414 minutes, p < 0.001) and postoperative hospital stay were shorter in the RAPD group (11 days vs. 14 days, p = 0.034). After PSM, the 5-year overall survival rate was comparable between MIPD and OPD for overall malignant disease (58.4% vs. 55.5%, p = 0.180). Conclusions: Both RAPD and TLPD are safe and feasible, and MIPD has clinical outcomes that are comparable to those of OPD. Although RAPD exhibits some advantages, its perioperative outcomes are similar to those associated with TLPD. A surgical method may be selected based on the convenience of surgical movements, medical costs, and operator experience.

6.
Alzheimers Res Ther ; 16(1): 202, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267169

RESUMO

BACKGROUND: Plasma neurofilament light chain (NfL) is a blood biomarker of neurodegeneration, including Alzheimer's disease. However, its usefulness may be influenced by common conditions in older adults, including amyloid-ß (Aß) deposition and cardiometabolic risk factors like hypertension, diabetes mellitus (DM), impaired kidney function, and obesity. This longitudinal observational study using the Alzheimer's Disease Neuroimaging Initiative cohort investigated how these conditions influence the prognostic capacity of plasma NfL. METHODS: Non-demented participants (cognitively unimpaired or mild cognitive impairment) underwent repeated assessments including the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) scores, hippocampal volumes, and white matter hyperintensity (WMH) volumes at 6- or 12-month intervals. Linear mixed-effect models were employed to examine the interaction between plasma NfL and various variables of interest, such as Aß (evaluated using Florbetapir positron emission tomography), hypertension, DM, impaired kidney function, or obesity. RESULTS: Over a mean follow-up period of 62.5 months, participants with a mean age of 72.1 years (n = 720, 48.8% female) at baseline were observed. Higher plasma NfL levels at baseline were associated with steeper increases in ADAS-Cog scores and WMH volumes, and steeper decreases in hippocampal volumes over time (all p-values < 0.001). Notably, Aß at baseline significantly enhanced the association between plasma NfL and longitudinal changes in ADAS-Cog scores (p-value 0.005) and hippocampal volumes (p-value 0.004). Regarding ADAS-Cog score and WMH volume, the impact of Aß was more prominent in cognitively unimpaired than in mild cognitive impairment. Hypertension significantly heightened the association between plasma NfL and longitudinal changes in ADAS-Cog scores, hippocampal volumes, and WMH volumes (all p-values < 0.001). DM influenced the association between plasma NfL and changes in ADAS-Cog scores (p-value < 0.001) without affecting hippocampal and WMH volumes. Impaired kidney function did not significantly alter the association between plasma NfL and longitudinal changes in any outcome variables. Obesity heightened the association between plasma NfL and changes in hippocampal volumes only (p-value 0.026). CONCLUSION: This study suggests that the prognostic capacity of plasma NfL may be amplified in individuals with Aß or hypertension. This finding emphasizes the importance of considering these factors in the NfL-based prognostic model for neurodegeneration in non-demented older adults.


Assuntos
Peptídeos beta-Amiloides , Biomarcadores , Proteínas de Neurofilamentos , Humanos , Feminino , Masculino , Idoso , Proteínas de Neurofilamentos/sangue , Estudos Longitudinais , Peptídeos beta-Amiloides/sangue , Prognóstico , Biomarcadores/sangue , Fatores de Risco Cardiometabólico , Tomografia por Emissão de Pósitrons , Idoso de 80 Anos ou mais , Disfunção Cognitiva/sangue , Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico por imagem , Hipocampo/patologia , Hipocampo/diagnóstico por imagem , Imageamento por Ressonância Magnética
7.
Sci Rep ; 14(1): 21215, 2024 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261511

RESUMO

Advances in next-generation sequencing technologies have led to elucidation of sensorineural hearing loss genetics and associated clinical impacts. However, studies on the functional pathogenicity of variants of uncertain significance (VUS), despite their close association with clinical phenotypes, are lacking. Here we identified compound heterozygous variants in ESRRB transcription factor gene linked to DFNB35, specifically a novel splicing variant (NM_004452.4(ESRRB): c.397 + 2T>G) in trans with a missense variant (NM_004452.4(ESRRB): c.1144C>T p.(Arg382Cys)) whose pathogenicity remains unclear. The splicing variant (c.397 + 2T>G) caused exon 4 skipping, leading to premature stop codon formation and nonsense-mediated decay. The p.(Arg382Cys) variant was classified as a VUS due to its particularly higher allele frequency among East Asian population despite disease-causing in-silico predictions. However, functional assays showed that p.(Arg382Cys) variant disrupted key intramolecular interactions, leading to protein instability. This variant also reduced transcriptional activity and altered expression of downstream target genes essential for inner ear function, suggesting genetic contribution to disease phenotype. This study expanded the phenotypic and genotypic spectrum of ESRRB in DFNB35 and revealed molecular mechanisms underlying ESRRB-associated DFNB35. These findings suggest that variants with high allele frequencies can also possess functional pathogenicity, providing a breakthrough for cases where VUS, previously unexplored, could be reinterpreted by elucidating their functional roles and disease-causing characteristics.


Assuntos
Perda Auditiva Neurossensorial , Receptores de Estrogênio , Feminino , Humanos , Masculino , Códon sem Sentido/genética , Frequência do Gene , Predisposição Genética para Doença , Perda Auditiva/genética , Perda Auditiva Neurossensorial/genética , Mutação de Sentido Incorreto , Linhagem , Splicing de RNA/genética , Receptores de Estrogênio/genética
8.
Cancers (Basel) ; 16(17)2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39272949

RESUMO

Single-port robotic-assisted thoracic surgery (SP-RATS) lobectomy using the da Vinci Xi system has been performed by several pioneers. However, due to the severe collisions and the steep learning curve, this approach is not yet widely used. This study aimed to evaluate the feasibility of SP-RATS lobectomy for large-sized non-small cell lung cancer (NSCLC). As we believe that for large-sized tumors it is reasonable to make a slightly larger incision, we performed SP-RATS lobectomy for large-sized NSCLC (greater than 5 cm) through a single incision (6-8 cm). Eleven patients underwent SP-RATS lobectomy using the da Vinci Xi system at our institution from April 2022 to May 2024. The median tumor size on computed tomography and on pathology was 6.6 cm [interquartile range (IQR), 6.1-7.5 cm] and 6 cm [IQR, 5.1-7.1], respectively. The median total operative time was 198 min [IQR, 159-260 min], and the median postoperative length of stay was 4 days [IQR, 4-10 days], with no major postoperative complications (≥grade III on the Clavien-Dindo classification). Our approach may combine the benefits of single-port surgery with those of robotic surgery and is safe, feasible, and may promote better outcomes in patients with large-sized NSCLC.

9.
ACS Nano ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39265148

RESUMO

Ferroelectric HfO2-based thin films have attracted much interest in the utilization of ferroelectricity at the nanoscale for next-generation electronic devices. However, the structural origin and stabilization mechanism of the ferroelectric phase are not understood because the film is typically nanocrystalline with active yet stochastic ferroelectric domains. Here, electron microscopy is used to map the in-plane domain network structures of epitaxially grown ferroelectric Y:HfO2 films in atomic resolution. The ferroelectricity is confirmed in free-standing Y:HfO2 films, allowing for investigating the structural origin for their ferroelectricity by 4D-STEM, high-resolution STEM, and iDPC-STEM. At the grain boundaries of <111>-oriented Pca21 orthorhombic grains, a high-symmetry mixed-(R3m, Pnm21) phase is induced, exhibiting enhanced polarization due to in-plane compressive strain. Nanoscale Pca21 orthorhombic grains and their grain boundaries with mixed-(R3m, Pnm21) phases of higher symmetry cooperatively determine the ferroelectricity of the Y:HfO2 film. It is also found that such ferroelectric domain networks emerge when the film thickness is beyond a finite value. Furthermore, in-plane mapping of oxygen positions overlaid on ferroelectric domains discloses that polarization is suppressed at vertical domain walls, while it is active when domains are aligned horizontally with subangstrom domain walls. In addition, randomly distributed 180° charged domain walls are confined by spacer layers.

10.
Comput Biol Med ; 182: 109078, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39265476

RESUMO

This study advances the automation of Parkinson's disease (PD) diagnosis by analyzing speech characteristics, leveraging a comprehensive approach that integrates a voting-based machine learning model. Given the growing prevalence of PD, especially among the elderly population, continuous and efficient diagnosis is of paramount importance. Conventional monitoring methods suffer from limitations related to time, cost, and accessibility, underscoring the need for the development of automated diagnostic tools. In this paper, we present a robust model for classifying speech patterns in Korean PD patients, addressing a significant research gap. Our model employs straightforward preprocessing techniques and a voting-based machine learning approach, demonstrating superior performance, particularly when training data is limited. Furthermore, we emphasize the effectiveness of the eGeMAPSv2 feature set in PD analysis and introduce new features that substantially enhance classification accuracy. The proposed model, achieving an accuracy of 84.73 % and an area under the ROC (AUC) score of 92.18 % on a dataset comprising 100 Korean PD patients and 100 healthy controls, offers a practical solution for automated diagnosis applications, such as smartphone apps. Future research endeavors will concentrate on enhancing the model's performance and delving deeper into the relationship between high-importance features and PD.

11.
Investig Clin Urol ; 65(5): 466-472, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39249919

RESUMO

PURPOSE: This study aims to prospectively analyze the effects of anticholinergic therapy using imidafenacin on detrusor overactivity occurring after robot-assisted radical prostatectomy (RARP). MATERIALS AND METHODS: Patients were followed-up at outpatient visits 2-4 weeks post-surgery (visit 2) to confirm the presence of urinary incontinence. Those confirmed with urinary incontinence were randomly assigned in a 1:1 ratio to the anticholinergic medication group (imidafenacin 0.1 mg twice daily) or the control group. Patients were followed-up at 1, 3, and 6 months post-surgery for observational assessments, including the International Prostate Symptom Score (IPSS) and Overactive Bladder Symptom Score (OABSS). RESULTS: A total of 49 patients (25 in the treatment group and 24 in the control group) were randomized for the study. There were no differences observed between the groups in terms of age, comorbidities, prostate size, or pathological staging. According to the IPSS questionnaire results, there was no statistically significant difference between the medication and control groups (p=0.161). However, when comparing storage and voiding symptoms separately, there was a statistically significant improvement in storage symptom scores (p=0.012). OABSS also revealed statistically significant improvement in symptoms from 3 months post-surgery (p=0.005), which persisted until 6 months post-surgery (IPSS storage: p=0.023, OABSS: p=0.013). CONCLUSIONS: In the case of urinary incontinence that occurs after RARP, even if the function of the intrinsic sphincter is sufficiently preserved, if urinary incontinence persists due to changes in the bladder, pharmacological therapy using imidafenacin can be beneficial in managing urinary incontinence.


Assuntos
Imidazóis , Prostatectomia , Neoplasias da Próstata , Incontinência Urinária , Humanos , Masculino , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Imidazóis/uso terapêutico , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Incontinência Urinária/etiologia , Estudos Prospectivos , Idoso , Neoplasias da Próstata/cirurgia , Pessoa de Meia-Idade , Bexiga Urinária Hiperativa/tratamento farmacológico , Bexiga Urinária Hiperativa/etiologia , Recuperação de Função Fisiológica , Complicações Pós-Operatórias/tratamento farmacológico , Resultado do Tratamento , Esquema de Medicação , Antagonistas Colinérgicos/uso terapêutico , Antagonistas Colinérgicos/administração & dosagem , Antagonistas Colinérgicos/efeitos adversos , Agentes Urológicos/uso terapêutico , Agentes Urológicos/administração & dosagem , Procedimentos Cirúrgicos Robóticos/efeitos adversos
12.
Pancreatology ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39256133

RESUMO

BACKGROUND/OBJECTIVES: The prognostic significance of circumferential resection margin (CRM) or circumferential surface (CS) in pancreatic head cancer is controversial. We investigated the survival outcomes according to CRM or CS involvement in pancreatoduodenectomy specimens of pancreatic ductal adenocarcinoma (PDAC). METHODS: A total of 102 pancreatoduodenectomy specimens after upfront surgery for PDAC between 2014 and 2018 were prospectively collected. The superior mesenteric vein/portal vein or superior mesenteric artery margins were classified as CRM, and the anterior or posterior surfaces as CS. Survival outcomes and recurrence were compared according to the CRM/CS status, which was categorized into R10mm, R11mm, and R0 (≥1 mm) by the 0 and 1 mm rules. RESULTS: For CRM, R10mm had significantly lower overall survival (OS) (P < 0.001) and disease-free survival (P < 0.001) rates than R11mm and R0, with no difference between R11mm and R0. For CS, R0 had a significantly higher OS rate (P < 0.001) than R10mm and R11mm, with no difference between R10mm and R11mm. In multivariable analysis, R10mm CRM was an independent risk factor for OS (hazard ratio 2.410, P = 0.003) and DFS (hazard ratio 5.019, P < 0.001). When CRM/CS were analyzed separately, only the R10mm superior mesenteric artery margin was significantly associated with local recurrence (P = 0.012). CONCLUSIONS: The results suggest that CRM involvement defined by the 0 mm rule is more appropriate than the 1 mm rule for predicting survival outcomes, but CS involvement defined by the 0 or 1 mm rules is not prognostically significant.

13.
Psychiatry Investig ; 21(9): 1025-1032, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39317242

RESUMO

OBJECTIVE: This study investigated to what extent a range of depressive symptoms was differentially present depending on age group in Korean population. METHODS: Data was pooled from five nationally representative surveys in which 29,418 respondents aged at least 18 years were interviewed face-to-face using the Korean version of the Composite International Diagnostic Interview. A total of 691 (2.1%) respondents were found to have had at least 1 episode of major depressive disorder (MDD) within the last 12 months. Logistic regression analysis was conducted to identify the association between age groups (18-39 years, 40-59 years, and 60 years or older) and 26 depressive symptoms among the respondents with MDD. RESULTS: Associations were observed between somatic symptoms-including insomnia, awakening 2 h earlier-and cognitive symptoms such as feelings of guilt, thoughts of death, and suicidal ideation with the older age group. Whereas, atypical depressive symptoms such as increased appetite, weight gain, and hypersomnia were associated with the younger age group. When adjusted for sociodemographic factors, symptoms such as depressed mood, awakening 2 h earlier, and feeling guilty in the older age group, and hypersomnia, psychomotor retardation, and worse in the morning in the younger age group still remained statistically significant. Furthermore, fatigue and decreased libido were newly associated with the younger age group. CONCLUSION: The findings of this study revealed distinct patterns of symptomatology in MDD based on age groups. These differences should be considered owing to their potential relevance to treatment response and prognosis in the clinical setting.

14.
PLoS One ; 19(9): e0310185, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39283834

RESUMO

Magnesium is a combustible metal that poses various safety risks, including fires and explosions. However, there are limited safety measures available to prevent and respond to potential fires and explosion incidents in the metal industry. In this study, the combustion process of Mg fires was closely examined using infrared thermal imaging, focusing on the effects of Mg powder size. For the experiment, Mg powder was burned by increasing the temperature to approximately 967.4 K using an ignition unit and controller equipped with a tungsten heater. Moreover, combustion velocity measurement experiments for Mg particle sizes of 75, 100, and 150 µm were conducted using the combustion velocity measurement device presented in the NFPA 484 standard. On combustion of Mg, flames are observed; smoke is emitted as demonstrated by thermal and flow visualization experiments. The combustion velocity measurement experiment results demonstrated that the greater the slope value (combustion velocity) for the combustion length over time, the faster is the combustion velocity, with the 75 µm particle size having the fastest combustion velocity. The results of this experiment can be utilized as references for Mg fire control design and to gain a better understanding of the scope of smoke and fire hazard investigation measures.


Assuntos
Incêndios , Magnésio , Tamanho da Partícula , Pós , Magnésio/química , Incêndios/prevenção & controle , Temperatura , Fumaça , Temperatura Alta
15.
Nat Neurosci ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251890

RESUMO

Brain function requires a constant supply of glucose. However, the brain has no known energy stores, except for glycogen granules in astrocytes. In the present study, we report that continuous oligodendroglial lipid metabolism provides an energy reserve in white matter tracts. In the isolated optic nerve from young adult mice of both sexes, oligodendrocytes survive glucose deprivation better than astrocytes. Under low glucose, both axonal ATP levels and action potentials become dependent on fatty acid ß-oxidation. Importantly, ongoing oligodendroglial lipid degradation feeds rapidly into white matter energy metabolism. Although not supporting high-frequency spiking, fatty acid ß-oxidation in mitochondria and oligodendroglial peroxisomes protects axons from conduction blocks when glucose is limiting. Disruption of the glucose transporter GLUT1 expression in oligodendrocytes of adult mice perturbs myelin homeostasis in vivo and causes gradual demyelination without behavioral signs. This further suggests that the imbalance of myelin synthesis and degradation can underlie myelin thinning in aging and disease.

16.
Nat Methods ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39266749

RESUMO

Spatial transcriptomics (ST) technologies have advanced to enable transcriptome-wide gene expression analysis at submicron resolution over large areas. However, analysis of high-resolution ST is often challenged by complex tissue structure, where existing cell segmentation methods struggle due to the irregular cell sizes and shapes, and by the absence of segmentation-free methods scalable to whole-transcriptome analysis. Here we present FICTURE (Factor Inference of Cartographic Transcriptome at Ultra-high REsolution), a segmentation-free spatial factorization method that can handle transcriptome-wide data labeled with billions of submicron-resolution spatial coordinates and is compatible with both sequencing-based and imaging-based ST data. FICTURE uses the multilayered Dirichlet model for stochastic variational inference of pixel-level spatial factors, and is orders of magnitude more efficient than existing methods. FICTURE reveals the microscopic ST architecture for challenging tissues, such as vascular, fibrotic, muscular and lipid-laden areas in real data where previous methods failed. FICTURE's cross-platform generality, scalability and precision make it a powerful tool for exploring high-resolution ST.

17.
J Extracell Vesicles ; 13(9): e12495, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39254228

RESUMO

Mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) have shown anti-inflammatory potential in multiple inflammatory diseases. In the March 2022 issue of the Journal of Extracellular Vesicles, it was shown that EVs from human MSCs can suppress severe acute respiratory distress syndrome, coronavirus 2 (SARS-CoV-2) replication and can mitigate the production and release of infectious virions. We therefore hypothesized that MSC-EVs have an anti-viral effect in SARS-CoV-2 infection in vivo. We extended this question to ask whether also other respiratory viral infections could be treated by MSC-EVs. Adipose stem cell-derived EVs (ASC-EVs) were isolated using tangential flow filtration from conditioned media obtained from a multi-flask cell culture system. The effects of the ASC-EVs were tested  in Vero E6 cells in vitro. ASC-EVs were also given i.v. to SARS-CoV-2 infected Syrian Hamsters, and H1N1 influenza virus infected mice. The ASC-EVs attenuated SARS-CoV-2 virus replication in Vero E6 cells and reduced body weight and signs of lung injury in infected Syrian hamsters. Furthermore, ASC-EVs increased the survival rate of influenza A-infected mice and attenuated signs of lung injury. In summary, this study suggests that ASC-EVs can have beneficial therapeutic effects in models of virus-infection-associated acute lung injury and may potentially be developed to treat lung injury in humans.


Assuntos
Lesão Pulmonar Aguda , COVID-19 , Vesículas Extracelulares , Vírus da Influenza A Subtipo H1N1 , Células-Tronco Mesenquimais , SARS-CoV-2 , Animais , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo , SARS-CoV-2/fisiologia , COVID-19/terapia , Lesão Pulmonar Aguda/terapia , Lesão Pulmonar Aguda/virologia , Camundongos , Células Vero , Humanos , Chlorocebus aethiops , Infecções por Orthomyxoviridae/terapia , Replicação Viral , Mesocricetus , Modelos Animais de Doenças , Masculino , Influenza Humana/terapia , Feminino
18.
Gland Surg ; 13(8): 1428-1436, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39282023

RESUMO

Background: In direct-to-implant breast reconstruction, accurate preoperative breast volume estimation is crucial for surgeons to select the appropriate implant volume, considering the cosmetic outcomes during surgery. We proposed the prediction model for intraoperative implant volume based on the preoperative estimated volume of the contralateral breast obtained through a three-dimensional surface imaging system (3DSI) as surgeons usually choose the implant volume on the breast which should be reconstructed considering symmetricity with the contralateral breast. Methods: We enrolled 97 patients from our single institution who underwent unilateral mastectomy with immediate breast reconstruction using smooth silicone implants between October 2021 and January 2023. Preoperatively, plastic surgeons measured the volume of the contralateral breast using the VECTRA XT 3D imaging system. Data on implant volume and the types of acellular dermal matrix used during surgery, determined by a single surgeon to ensure symmetry, were also collected. Linear regression analysis was utilized to construct the predictive model. Results: In the multiple linear regression analysis with preoperative contralateral breast volume, age, and body mass index as variables, the coefficient of determination of the model expressed as R squared (R2) was 0.554, and except for age, the other variables were statistically significant. When replaced by mastectomy volume instead of age, R2 increased to 0.723 and all variables were significant. Conclusions: 3DSI can be helpful for preoperative surgical planning and postoperative outcome simulation. With our multiple linear regression model, we can predict the intraoperative implant volume using preoperative contralateral breast volume measured by the 3D scans.

19.
Front Aging Neurosci ; 16: 1470919, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39286459

RESUMO

Objective: Tinnitus may be associated with various brain changes. However, the degenerative changes in patients with tinnitus have not been extensively investigated. We aimed to evaluate degenerative, structural, and functional brain changes in patients with mild cognitive impairment (MCI) who also suffer from tinnitus. Materials and methods: This study included participants aged 60 to 80 years with MCI and a hearing level better than 40 dB. The participants were classified into two groups: MCI with tinnitus (MCI-T) and MCI without tinnitus (MCI-NT). All patients underwent Tinnitus Handicap Inventory (THI), 3 T brain MRI, F18-florapronol PET, and F18-FDG PET. Results: The MCI-T group exhibited higher ß-amyloid deposition in the superior temporal gyrus, temporal pole, and middle temporal gyrus compared to the MCI-NT group (p < 0.05 for all). Additionally, the MCI-T group showed increased metabolism in the inferior frontal gyrus, insula, and anterior cingulate cortex (ACC) (p < 0.005 for all). The THI score was strongly correlated with increased volume in the insula, ACC, superior frontal gyrus, supplementary motor area, white matter near the hippocampus, and precentral gyrus (p < 0.05 for all). Moreover, the MCI-T group demonstrated higher metabolic activity in the default mode network (DMN) and lower activity in the executive control network (ECN) (p < 0.05 for all). In the MCI-T group, the posterior DMN was positively correlated with the visual network and negatively with the ECN, whereas in the MCI-NT group, it correlated positively with the ECN. Conclusion: The MCI-T group exhibited greater ß-amyloid accumulation in the auditory cortex and more extensive changes across various brain networks compared with the MCI-NT group, potentially leading to diverse clinical symptoms such as dementia with semantic deficits or depression. Tinnitus in MCI patients may serve as a biomarker for degenerative changes in the temporal lobe and alterations in brain network dynamics.

20.
J Craniofac Surg ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287417

RESUMO

The epidemiology of facial fractures is continuously evolving due to various influencing factors, including social, economic, and technological advancements. Thus, an updated analysis of facial bone fractures is necessary. This study aimed to provide an updated epidemiological analysis of facial bone fractures and assess severity using multiple factors. We retrospectively reviewed patients who underwent facial bone fracture surgery at 3 teaching hospitals in South Korea between January 2015 and December 2020. Data collected included patient demographics (sex and age), trauma mechanism, alcohol intoxication status, and fracture types. Trauma mechanisms were categorized into 7 groups: assault, fall, sports, occupational injury, motor vehicle crash, bicycle, and personal mobility. Severity was assessed using the modified facial injury severity scale. A total of 5953 patients (4437 males and 1516 females) were included, with ages ranging from 1 to 92 years (mean age: 36.37±18.61 y). A steady decline in the number of patients was observed from 2015 to 2020. Falls were the most common cause of facial fractures (2300 cases, 39%), and nasal bone fractures were the most frequent type (3683 cases, 46%). The number of elderly patients (> 60 y) and injuries caused by personal mobility devices increased steadily. Male sex and alcohol intoxication were associated with higher severity scores. Motor vehicle crashes had the highest severity scores (2.246). While the incidence of facial bone fractures has decreased in recent years, the proportion of elderly patients and injuries caused by personal mobility devices is increasing, posing a significant burden on the health care system.

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