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Background: The interrelation between infections, subjective cognitive decline (SCD), and dementia development is recognized, but not fully understood. This study explored the combined effect of specific infections and SCD on the risk of dementia. Objectives: To assess the influence of Helicobacter pylori, herpes simplex virus, varicella-zoster virus, and human papillomavirus on dementia risk in individuals with varying cognitive statuses, especially focusing on those with and without SCD. Methods: A cohort of 1,100,540 participants aged 66 years from the Korean National Health Insurance Service was divided into cognitively preserved (CP, n = 825,405) and SCD (n = 275,135) groups. This study analyzed the effects of single, dual, and triple infections on the risk of overall dementia, Alzheimer's disease (AD), and vascular dementia (VaD) using incidence rates and hazard ratios. Results: The SCD group consistently showed a doubled risk of dementia, particularly AD, regardless of the number of infections. In the initial data, both the presence and number of infections, especially in the CP group, were associated with an increased dementia incidence and risk; however, this correlation disappeared after adjusting for covariates, hinting at a possible protective effect. Conclusion: Our findings emphasize that, while SCD is a steadfast risk factor for dementia, the role of infections is layered, subject to various influences, and requires more comprehensive exploration to fully understand their impact on dementia development.
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Background: Alzheimer's disease (AD) encompasses a spectrum that may progress from mild cognitive impairment (MCI) to full dementia, characterized by amyloid-beta and tau accumulation. Transcranial direct current stimulation (tDCS) is being investigated as a therapeutic option, but its efficacy in relation to individual genetic and biological risk factors remains underexplored. Objective: To evaluate the effects of a two-week anodal tDCS regimen on the left dorsolateral prefrontal cortex, focusing on functional connectivity changes in neural networks in MCI patients resulting from various possible underlying disorders, considering individual factors associated to AD such as amyloid-beta deposition, APOE ϵ4 allele, BDNF Val66Met polymorphism, and sex. Methods: In a single-arm prospective study, 63 patients with MCI, including both amyloid-PET positive and negative cases, received 10 sessions of tDCS. We assessed intra- and inter-network functional connectivity (FC) using fMRI and analyzed interactions between tDCS effects and individual factors associated to AD. Results: tDCS significantly enhanced intra-network FC within the Salience Network (SN) and inter-network FC between the Central Executive Network and SN, predominantly in APOE ϵ4 carriers. We also observed significant sex*tDCS interactions that benefited inter-network FC among females. Furthermore, the effects of multiple modifiers, particularly the interaction of the BDNF Val66Met polymorphism and sex, were evident, as demonstrated by increased intra-network FC of the SN in female Met non-carriers. Lastly, the effects of tDCS on FC did not differ between the group of 26 MCI patients with cerebral amyloid-beta deposition detected by flutemetamol PET and the group of 37 MCI patients without cerebral amyloid-beta deposition. Conclusions: The study highlights the importance of precision medicine in tDCS applications for MCI, suggesting that individual genetic and biological profiles significantly influence therapeutic outcomes. Tailoring interventions based on these profiles may optimize treatment efficacy in early stages of AD.
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BACKGROUND: Dementia, a growing global health issue, affects older adults and specific groups like long-term cancer survivors. The link between cancer survival and dementia is debated. Multiple myeloma (MM), a common blood cancer in older adults, is often linked with cognitive issues. This study investigated dementia incidence in long-term MM survivors using Korean national data. METHODS: A retrospective case-control study used data from the Korea National Health Insurance Service (KNHIS), covering about 50 million Koreans. Patients diagnosed with MM between 2009 and 2020 formed the case cohort, while the control cohort included matched individuals without MM using propensity-score matching. Analyzing baseline characteristics, comorbidities, and socioeconomic status, the primary outcome was dementia incidence identified via ICD-10 codes. Statistical methods included Kaplan-Meier plots, cause-specific and Fine-Gray subdistribution hazard models, and a 3-year landmark analysis for immortal time bias. RESULTS: The study included 33,864 patients, with 16,932 in each cohort. The overall cumulative dementia incidence was lower in the MM cohort compared to controls. However, in the first 3 years, MM patients had a higher dementia risk (HR: 1.711, 95% CI, 1.562-1.874) than controls. After 3 years, the risk significantly decreased (HR: 0.625, 95% CI, 0.560-0.696). Age-specific analysis showed a consistent pattern, particularly among MM patients aged 70-79, where dementia risk increased post-3 years. CONCLUSION: This study reveals a lower long-term dementia risk in MM survivors compared to non-MM individuals. Further prospective studies are needed to confirm these findings and explore the underlying mechanisms.
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BACKGROUND: Diabetic retinopathy (DR), a chronic and progressive microvascular complication of diabetes mellitus, substantially threatens vision and is a leading cause of blindness among working-age individuals worldwide. Traditional diagnostic methods, such as ophthalmoscopy and fluorescein angiography are nonquantitative, invasive, and time consuming. Analysis of protein biomarkers in tear fluid offers noninvasive insights into ocular and systemic health, aiding in early DR detection. This study introduces a surface acoustic wave (SAW) microchip that rapidly enhances fluorescence in bead-based immunoassays for the sensitive and noninvasive DR detection from human tear samples. RESULTS: The device facilitated particle mixing for immunoassay formation and particle concentration in the droplet, resulting in an enhanced immunofluorescence signal. This detachable SAW microchip allows the disposal of the cover glass after every use, thereby improving the reusability of the interdigital transducer and minimizing potential cross-contamination. A preliminary clinical test was conducted on a cohort of 10 volunteers, including DR patients and healthy individuals. The results demonstrated strong agreement with ELISA studies, validating the high accuracy rate of the SAW microchip. SIGNIFICANCE: This comprehensive study offers significant insights into the potential application of a novel SAW microchip for the early detection of DR in individuals with diabetes. By utilizing protein biomarkers found in tear fluid, the device facilitates noninvasive, rapid, and sensitive detection, potentially revolutionizing DR diagnostics and improving patient outcomes through timely intervention and management of this vision-threatening condition.
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Retinopatía Diabética , Lágrimas , Humanos , Lágrimas/química , Retinopatía Diabética/diagnóstico , Inmunoensayo/métodos , Sonido , Técnicas Biosensibles/instrumentación , Biomarcadores/análisis , Propiedades de SuperficieRESUMEN
OBJECTIVE: The hippocampus plays a critical role in cognitive networks. The anterior hippocampus is vulnerable to early-life stress and socioeconomic status (SES) with alterations persisting beyond childhood. How SES modifies the relationship between early hippocampal development and cognition remains poorly understood. This study examined associations between SES, structural and functional development of neonatal hippocampus, and 18-month cognition in very preterm neonates. METHODS: In total, 179 preterm neonates were followed prospectively. Structural and resting-state functional MRI were obtained early-in-life and at term-equivalent age (median 32.9 and 41.1 weeks post-menstrual age) to calculate anterior and posterior hippocampal volumes and hippocampal functional connectivity strength. Eighteen-month cognition was assessed via Bayley-III. Longitudinal statistical analysis using generalized estimating equations, accounting for birth gestational age, post-menstrual age at scan, sex, and motion, was performed. RESULTS: SES, measured as maternal education level, modified associations between anterior but not posterior hippocampal volumes and 18-month cognition (interaction term p = 0.005), and between hippocampal connectivity and cognition (interaction term p = 0.05). Greater anterior hippocampal volumes and hippocampal connectivity were associated with higher cognitive scores only in the lowest SES group. Maternal education alone did not predict neonatal hippocampal volume from early-in-life and term. INTERPRETATION: SES modified the relationship between neonatal hippocampal development and 18-month cognition in very preterm neonates. The lack of direct association between maternal education and neonatal hippocampal volumes indicates that socio-environmental factors beyond the neonatal period contribute to modifying the relationship between hippocampal development and cognition. These findings point toward opportunities to more equitably promote optimal neurodevelopmental outcomes in very preterm infants.
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The impact of peptic ulcer disease (PUD) and Helicobacter pylori (H. pylori) eradication therapy on dementia risk in high H. pylori prevalence populations remains uncertain. This study investigates the relationship between PUD, H. pylori eradication, and dementia risk, including Alzheimer's disease (AD), in an elderly South Korean cohort, considering age and eradication timing. Data from the Korean National Health Insurance Service (2002-2015) for individuals aged 55-79 were analyzed. Participants were divided based on PUD and H. pylori therapy status. Propensity score matching was used to evaluate dementia incidence and hazard ratios over 5 and 10 years, alongside the timing of eradication therapy. PUD is linked to higher dementia risk at 5 and 10 years, more for overall dementia than AD, with eradication status not significantly altering the risk. Age-specific analysis showed increased AD risk in the 60s and 70s age groups. Late eradication therapy is correlated with a higher dementia risk. PUD is a risk factor for dementia in elderly South Koreans, particularly with delayed H. pylori therapy. The findings emphasize timely H. pylori management and its potential role in neurodegenerative disease prevention.
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This study aimed to perform clinical and radiographic investigations of the effect of regenerative endodontic procedures (REPs) with and without concentrated growth factor (CGF). Fifty-six non-vital and immature teeth from 56 patients were randomly categorized into two groups. Following chemical and mechanical preparation, REPs with and without CGF as a scaffold was induced in the blood clot (BLC) group and the CGF group. All patients were clinically and radiographically evaluated at 6-month and 12-month intervals to monitor their progress and treatment outcomes. When considering the total number of patients, the follow-up rate was 96.4% (54 out of 56 patients) over a 12-month period. Favorable clinical and radiographic outcomes were observed in 92.6% of patients (25 out of 27) in both the CGF and BLC groups; there were no significant differences between the two groups in these respects (p > 0.05). Notable differences were, however, observed in radiographic measurements relating to the development of root length and radiographic root area when compared between the CGF and BLC groups at both the 6-month and 12-month follow-up intervals (p < 0.05). REPs have been proven to represent a conservative and effective approach for promoting maturogenesis in non-vital and immature teeth. Furthermore, the incorporation of CGF as scaffolds holds promising potential for enhancing the desired biological outcomes of this regenerative technique. These findings highlight the clinical significance and potential benefits of CGF supplementation in REPs, further supporting its application in the field of endodontics.
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Diente Premolar , Péptidos y Proteínas de Señalización Intercelular , Endodoncia Regenerativa , Andamios del Tejido , Diente no Vital , Humanos , Endodoncia Regenerativa/métodos , Péptidos y Proteínas de Señalización Intercelular/uso terapéutico , Masculino , Niño , Femenino , Diente Premolar/diagnóstico por imagen , Diente no Vital/terapia , Diente no Vital/diagnóstico por imagen , Mandíbula/diagnóstico por imagen , Adolescente , Resultado del Tratamiento , Raíz del Diente/diagnóstico por imagenRESUMEN
BACKGROUND: Previous studies suggested an association between cataract surgery and retinal vascular occlusion. However, the association may be attributable to detection bias because postoperative monitoring may be more frequent for those who receive cataract surgery than for those who do not. DESIGN: Population-based cohort study using target trial emulation framework. METHODS: We included patients with cataract aged 50 years and older receiving cataract surgery or nonsurgical interventions identified from the Taiwan National Health Insurance Research Database between 2003 and 2018, matched by propensity score. The primary outcome was retinal vascular occlusion. Cox proportional hazards models were used to compare surgery and control groups. Additional analyses were restricted to patients who had undergone fundoscopic examination within 6 months prior to cataract surgery to address the issue of detection bias. RESULTS: We included 577,129 cataract surgery and control pairs. We found the hazard ratio (HR) for retinal vascular occlusion after cataract surgery was 1.23 (95% confidence interval (CI): 1.17-1.29), compared with the control group. Secondary outcome analyses yielded similar results for retinal artery occlusion (HR: 1.13, 95% CI: 1.02-1.26) and retinal vein occlusion (HR: 1.26, 95% CI: 1.20-1.33). However, no risk of retinal vascular occlusion was observed among patients who had received fundoscopic examinations (HR: 1.06, 95% CI: 0.98-1.15) at baseline. CONCLUSIONS: Our study underscored the importance of conducting complete baseline fundoscopic examinations before cataract surgery to clarify whether postoperative conditions are due to patients' underlying diseases or unintended complications of cataract surgery.
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Background/Aims: Alcohol-associated liver disease (ALD) is a public health concern. ALD patients often have psychiatric comorbidities, but the effects of psychiatric interventions on ALD are not well-established. This study explores the prognostic impact of psychiatric intervention on ALD within UK Biobank cohort. Methods: This population-based study included 2,417 ALD patients from the UK Biobank cohort. Psychiatric intervention was defined by a consultation with psychiatrists during hospitalization or a history of medication related to alcohol use disorder and psychiatric comorbidities. Survival analysis was conducted, incorporating propensity score matching (PSM), to precisely assess the impact of psychiatric intervention. Results: Among 2,417 ALD patients, those with F10 (mental disorders due to alcohol) codes had poorer survival outcomes. Psychiatric intervention significantly improved the outcomes of both all-cause and liver-related mortality and reduced the incidence of liver cirrhosis. In subgroup or 2-year landmark analyses, psychiatric intervention consistently showed a survival benefit in ALD patients. In the multivariate analysis, psychiatric intervention was identified as a favorable prognostic factor (hazard ratio, 0.780; P = 0.002 after PSM). Conclusions: This study demonstrates the favorable effect of psychiatric intervention in ALD patients with psychiatric comorbidities. These findings emphasize the importance of integrated management for ALD patients to address both their medical and psychiatric aspects. Therefore, we suggest the potential benefits of early psychiatric interventions in improving survival outcomes in ALD.
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Despite the growing interest in precision medicine-based therapies for Alzheimer's disease (AD), little research has been conducted on how individual AD risk factors influence changes in cognitive function following transcranial direct current stimulation (tDCS). This study evaluates the cognitive effects of sequential tDCS on 63 mild cognitive impairment (MCI) patients, considering AD risk factors such as amyloid-beta deposition, APOE ε4, BDNF polymorphism, and sex. Using both frequentist and Bayesian methods, we assessed the interaction of tDCS with these risk factors on cognitive performance. Notably, we found that amyloid-beta deposition significantly interacted with tDCS in improving executive function, specifically Stroop Word-Color scores, with strong Bayesian support for this finding. Memory enhancements were differentially influenced by BDNF Met carrier status. However, sex and APOE ε4 status did not show significant effects. Our results highlight the importance of individual AD risk factors in modulating cognitive outcomes from tDCS, suggesting that precision medicine may offer more effective tDCS treatments tailored to individual risk profiles in early AD stages.
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Enfermedad de Alzheimer , Teorema de Bayes , Cognición , Disfunción Cognitiva , Estimulación Transcraneal de Corriente Directa , Humanos , Enfermedad de Alzheimer/terapia , Estimulación Transcraneal de Corriente Directa/métodos , Masculino , Femenino , Disfunción Cognitiva/terapia , Disfunción Cognitiva/etiología , Anciano , Factores de Riesgo , Péptidos beta-Amiloides/metabolismo , Apolipoproteína E4/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Persona de Mediana EdadRESUMEN
BACKGROUND: Recent studies suggest that 5α-reductase inhibitors (5ARIs) for benign prostate hyperplasia (BPH) result in abnormal retinal anatomical alteration. OBJECTIVE: To compare age-related macular degeneration (AMD) incidence in BPH patients receiving 5ARIs or tamsulosin. DESIGN: Retrospective, population-based cohort study using new-user and active-comparator design. SETTING: General population. SUBJECTS: Males with BPH, newly receiving 5ARIs or tamsulosin from 2010 to 2018. METHODS: Data were extracted from Taiwan's National Health Insurance Research Database. We used Cox proportional hazards model with 1:4 propensity score (PS) matching, based on intention-to-treat analysis to determine the risk of incident AMD. Sensitivity analyses included an as-treated approach and weighting-based PS methods. We also separately reported the risks of incident AMD in patients receiving finasteride and dutasteride to determine risk differences among different 5ARIs. RESULTS: We included 13 586 5ARIs users (mean age: 69 years) and 54 344 tamsulosin users (mean age: 68.37 years). After a mean follow-up of 3.7 years, no differences were observed in the risk of incident AMD between 5ARIs and tamsulosin users [hazard ratio (HR): 1.06; 95% confidence intervals (95% CI): 0.98-1.15], with similar results from sensitivity analyses. However, increased risk of incident age-related macular degeneration was observed in patients receiving dutasteride [HR: 1.13; 95% CI: 1.02-1.25], but not in those receiving finasteride [HR: 0.99; 95% CI: 0.87-1.12], in the subgroup analyses. CONCLUSIONS: We found no difference between 5ARIs and tamsulosin regarding the incidence of AMD in BPH patients. However, the risk profiles for AMD differed slightly between dutasteride and finasteride, suggesting that the potency of androgen inhibition is a factor related to AMD incidence.
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Inhibidores de 5-alfa-Reductasa , Dutasterida , Finasterida , Degeneración Macular , Hiperplasia Prostática , Tamsulosina , Humanos , Inhibidores de 5-alfa-Reductasa/efectos adversos , Inhibidores de 5-alfa-Reductasa/uso terapéutico , Masculino , Anciano , Hiperplasia Prostática/tratamiento farmacológico , Hiperplasia Prostática/epidemiología , Estudios Retrospectivos , Taiwán/epidemiología , Incidencia , Degeneración Macular/epidemiología , Degeneración Macular/diagnóstico , Degeneración Macular/inducido químicamente , Dutasterida/uso terapéutico , Dutasterida/efectos adversos , Tamsulosina/uso terapéutico , Tamsulosina/efectos adversos , Finasterida/efectos adversos , Finasterida/uso terapéutico , Factores de Riesgo , Persona de Mediana Edad , Medición de Riesgo , Bases de Datos FactualesRESUMEN
To determine a rapid and accurate method for locating the keypoint and "keyhole" in the suboccipital retrosigmoid keyhole approach. (1) Twelve adult skull specimens were selected to locate the anatomical landmarks on the external surface of the skull.The line between the infraorbital margin and superior margin of the external acoustic meatus was named the baseline. A coordinate system was established using the baseline and its perpendicular line through the top point of diagastric groove.The perpendicular distance (x), and the horizontal distance (y) between the central point of the "keyhole" and the top point of the digastric groove in that coordinate system were measured. The method was applied to fresh cadaveric specimens and 53 clinical cases to evaluate its application value. (1) x and y were 14.20 ± 2.63 mm and 6.54 ± 1.83 mm, respectively (left) and 14.95 ± 2.53 mm and 6.65 ± 1.61 mm, respectively (right). There was no significant difference between the left and right sides of the skull (P > 0.05). (2) The operative area was satisfactorily exposed in the fresh cadaveric specimens, and no venous sinus injury was observed. (3) In clinical practice, drilling did not cause injury to venous sinuses, the mean diameter of the bone windows was 2.0-2.5 cm, the mean craniotomy time was 26.01 ± 3.46 min, and the transverse and sigmoid sinuses of 47 patients were well-exposed. We propose a "one point, two lines, and two distances" for "keyhole" localization theory, that is we use the baseline between the infraorbital margin and superior margin of the external acoustic meatus and the perpendicular line to the baseline through the top point of the digastric groove to establish a coordinate system. And the drilling point was 14.0 mm above and 6.5 mm behind the top point of the digastric groove in the coordinate system.
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Cadáver , Senos Craneales , Craneotomía , Humanos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Senos Craneales/anatomía & histología , Senos Craneales/cirugía , Craneotomía/métodos , Procedimientos Neuroquirúrgicos/métodos , Anciano , Adulto Joven , Senos Transversos/anatomía & histología , Senos Transversos/cirugía , Cráneo/anatomía & histología , Cráneo/cirugíaRESUMEN
BACKGROUND: Inflammatory indices derived from complete blood tests have been reported to be associated with poor outcomes in patients with atrial fibrillation (AF). The data about the relationship between inflammatory indices and left atrial appendage thrombus (LAAT) or dense spontaneous echo contrast (SEC) are limited. AIM: To explore the value of inflammatory indices for predicting the presence of LAAT or dense SEC in nonvalvular AF patients. METHODS: A total of 406 patients with nonvalvular AF who underwent transesophageal echocardiography were included and divided into two groups based on the presence (study group) or absence (control group) of LAAT or dense SEC. Inflammatory indices, including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR), were calculated from complete blood analysis. The associations of inflammatory indices with LAAT/dense SEC were analyzed using logistic regression. RESULTS: LAAT and dense SEC were detected in 11 (2.7%) and 42 (10.3%) patients, respectively. The PLR only showed an association with LAAT/dense SEC in the univariate model. Elevated NLR (odds ratio [OR] = 1.48, 95% confidence interval [CI]: 1.11-1.98, P = 0.007) and reduced LMR (OR = 0.59, 95%CI: 0.41-0.83, P = 0.003) were found to be independent risk factors for the presence of LAAT/dense SEC. The areas under the NLR and LMR curves for predicting LAAT/dense SEC were 0.73 (95%CI: 0.66-0.80, P < 0.001) and 0.73 (95%CI: 0.65-0.81, P < 0.001), respectively, while the cutoff values were 2.8 (sensitivity: 69.8%; specificity: 64.0%) and 2.4 (sensitivity: 71.7%; specificity: 60.6%), respectively. CONCLUSION: Increased NLR and decreased LMR may predict LAAT/dense SEC in patients with nonvalvular AF.
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Accurate quantification of amyloid positron emission tomography (PET) is essential for early detection of and intervention in Alzheimer's disease (AD) but there is still a lack of studies comparing the performance of various automated methods. This study compared the PET-only method and PET-and-MRI-based method with a pre-trained deep learning segmentation model. A large sample of 1180 participants in the Catholic Aging Brain Imaging (CABI) database was analyzed to calculate the regional standardized uptake value ratio (SUVR) using both methods. The logistic regression models were employed to assess the discriminability of amyloid-positive and negative groups through 10-fold cross-validation and area under the receiver operating characteristics (AUROC) metrics. The two methods showed a high correlation in calculating SUVRs but the PET-MRI method, incorporating MRI data for anatomical accuracy, demonstrated superior performance in predicting amyloid-positivity. The parietal, frontal, and cingulate importantly contributed to the prediction. The PET-MRI method with a pre-trained deep learning model approach provides an efficient and precise method for earlier diagnosis and intervention in the AD continuum.
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Enfermedad de Alzheimer , Encéfalo , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Humanos , Tomografía de Emisión de Positrones/métodos , Imagen por Resonancia Magnética/métodos , Femenino , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Masculino , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Amiloide/metabolismo , Aprendizaje Profundo , Anciano de 80 o más Años , Persona de Mediana Edad , Curva ROCRESUMEN
The transfer of land plays a crucial role in revitalizing land resources, acting as a catalyst for promoting the high-quality development of agriculture. The land transfer ratio is a crucial metric for assessing the progress of rural land transfer and the effective allocation of rural land resources. Thus, this study examines the rural land transfer ratio across 30 provinces in China from 2005 to 2020. The study explores the distribution characteristics of the ratio using the rank-size rule and trend surface analysis. The LISA space-time transition method is employed to analyze the spatial and temporal dynamics of the rural land transfer ratio and examine its convergence. The study aims to comprehensively analyze the spatial distribution characteristics and evolutionary patterns of rural land transfer in China, illustrating the convergence and influencing factors during the development process. The results indicate that: (1) The rural land transfer ratio in China is generally increasing, with a spatial pattern showing an upward trend from west to east and from north to south. The main spatial contrast is between the eastern and western regions, with a relatively minor distinction between the southern and northern regions. (2) The LISA space-time transition highlights a significant spatial locking effect in China's rural land transfer ratio, suggesting strong spatial integration in its evolution. (3) Clear indications of σ convergence, absolute ß convergence, and club convergence are evident in China's rural land transfer ratio. This suggests a gradual reduction in internal disparities among provinces and regions, where areas with higher land transfer ratios influence spatial spillover effects on adjacent lower areas. (4) Factors such as transportation infrastructure, irrigation, water conservancy construction, and farmers' per capita income collectively influence the spatial and temporal evolution of China's rural land transfer ratio, with dominant driving factors varying across different periods.
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Agricultura , Análisis Espacio-Temporal , China , Conservación de los Recursos Naturales/legislación & jurisprudencia , HumanosRESUMEN
INTRODUCTION: Despite prior research on the association between sarcopenia and cognitive impairment in the elderly, a comprehensive model that integrates various brain pathologies is still lacking. METHODS: We used data from 528 non-demented older adults with or without sarcopenia in the Catholic Aging Brain Imaging (CABI) database, containing magnetic resonance imaging scans, positron emission tomography scans, and clinical data. We also measured three key components of sarcopenia: skeletal muscle index (SMI), hand grip strength (HGS), and the five times sit-to-stand test (5STS). RESULTS: All components of sarcopenia were significantly correlated with global cognitive function, but cortical thickness and amyloid-beta (Aß) retention had distinctive relationships with each measure. In the path model, brain atrophy resulting in cognitive impairment was mediated by Aß retention for SMI and periventricular white matter hyperintensity for HGS, but directly affected by the 5STS. DISCUSSION: Treatments targeting each sub-domain of sarcopenia should be considered to prevent cognitive decline. HIGHLIGHTS: We identified distinct impacts of three sarcopenia measures on brain structure and Aß. Muscle mass is mainly associated with Aß and has an influence on the brain atrophy. Muscle strength linked with periventricular WMH and brain atrophy. Muscle function associated with cortical thinning in specific brain regions. Interventions on sarcopenia may be important to ease cognitive decline in the elderly.
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Encéfalo , Disfunción Cognitiva , Fuerza de la Mano , Imagen por Resonancia Magnética , Neuroimagen , Sarcopenia , Humanos , Sarcopenia/diagnóstico por imagen , Sarcopenia/patología , Disfunción Cognitiva/diagnóstico por imagen , Masculino , Anciano , Femenino , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Fuerza de la Mano/fisiología , Tomografía de Emisión de Positrones , Anciano de 80 o más Años , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/patología , Péptidos beta-Amiloides/metabolismo , Imagen Multimodal , Envejecimiento/patologíaRESUMEN
BACKGROUND: Changing the course duration or timing of subjects in learning pathways would influence medical students' learning outcomes. Curriculum designers need to consider the strategy of reducing cognitive load and evaluate it continuously. Our institution underwent gradual curricular changes characterized by reducing cognitive load since 2000. Therefore, we wanted to explore the impact of this strategy on our previous cohorts. METHODS: This cohort study explored learning pathways across academic years of more than a decade since 2000. Eight hundred eighty-two medical students between 2006 and 2012 were included eventually. Learning outcomes included an average and individual scores of subjects in different stages. Core subjects were identified as those where changes in duration or timing would influence learning outcomes and constitute different learning pathways. We examined whether the promising learning pathway defined as the pathway with the most features of reducing cognitive load has higher learning outcomes than other learning pathways in the exploring dataset. The relationship between features and learning outcomes was validated by learning pathways selected in the remaining dataset. RESULTS: We found nine core subjects, constituting four different learning pathways. Two features of extended course duration and increased proximity between core subjects of basic science and clinical medicine were identified in the promising learning pathway 2012, which also had the highest learning outcomes. Other pathways had some of the features, and pathway 2006 without such features had the lowest learning outcomes. The relationship between higher learning outcomes and cognitive load-reducing features was validated by comparing learning outcomes in two pathways with and without similar features of the promising learning pathway. CONCLUSION: An approach to finding a promising learning pathway facilitating students' learning outcomes was validated. Curricular designers may implement similar design to explore the promising learning pathway while considering potential confounding factors, including students, medical educators, and learning design of the course.
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Cognición , Aprendizaje , Humanos , Estudios de Cohortes , Estudiantes de Medicina/psicología , Curriculum , Femenino , MasculinoRESUMEN
Understanding how widespread species adapt to variation in abiotic conditions across their ranges is fundamental to ecology. Insight may come from studying how among-population variation (APV) in the common garden corresponds with the environmental conditions of source populations. However, there are no such studies comparing native vs non-native populations across multiple life stages. We examined APV in the performance and functional traits of 59 Conyza canadensis populations, in response to drought, across large aridity gradients in the native (North America) and non-native (Eurasia) ranges in three experiments. Our treatment (dry vs wet) was applied at the recruitment, juvenile, and adult life stages. We found contrasting patterns of APV in drought responses between the two ranges. In the native range, plant performance was less reduced by drought in populations from xeric than mesic habitats, but such relationship was not apparent for non-native populations. These range-specific patterns were consistent across the life stages. The weak adaptive responses of non-native populations indicate that they can become highly abundant even without complete local adaptation to abiotic environments and suggest that long-established invaders may still be evolving to the abiotic environment. These findings may explain lag times in invasions and raise concern about future expansions.
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Sequías , Especies Introducidas , Variación Biológica Poblacional , Adaptación Fisiológica , Ecosistema , Estadios del Ciclo de Vida , AguaRESUMEN
Proper topographically organized neural connections between the thalamus and the cerebral cortex are mandatory for thalamus function. Thalamocortical (TC) fiber growth begins during the embryonic period and completes by the third trimester of gestation, so that human neonates at birth have a thalamus with a near-facsimile of adult functional parcellation. Whether congenital neocortical anomaly (e.g., lissencephaly) affects TC connection in humans is unknown. Here, via diffusion MRI fiber-tractography analysis of long-term formalin-fixed postmortem fetal brain diagnosed as lissencephaly in comparison with an age-matched normal one, we found similar topological patterns of thalamic subregions and of internal capsule parcellated by TC fibers. However, lissencephaly fetal brain showed white matter structural changes, including fewer/less organized TC fibers and optic radiations, and much less cortical plate invasion by TC fibers - particularly around the shallow central sulcus. Diffusion MRI fiber tractography of normal fetal brains at 15, 23, and 26 gestational weeks (GW) revealed dynamic volumetric change of each parcellated thalamic subregion, suggesting coupled developmental progress of the thalamus with the corresponding cortex. Moreover, from GW23 and GW26 normal fetal brains, TC endings in the cortical plate could be delineated to reflect cumulative progressive TC invasion of cortical plate. By contrast, lissencephaly brain showed a dramatic decrease in TC invasion of the cortical plate. Our study thus shows the feasibility of diffusion MRI fiber tractography in postmortem long-term formalin-fixed fetal brains to disclose the developmental progress of TC tracts coordinating with thalamic and neocortical growth both in normal and lissencephaly fetal brains at mid-gestational stage.
Asunto(s)
Corteza Cerebral , Imagen de Difusión Tensora , Lisencefalia , Vías Nerviosas , Tálamo , Humanos , Tálamo/diagnóstico por imagen , Tálamo/patología , Tálamo/embriología , Corteza Cerebral/patología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/embriología , Lisencefalia/patología , Lisencefalia/diagnóstico por imagen , Vías Nerviosas/patología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/embriología , Imagen de Difusión Tensora/métodos , Feto/patología , Feto/diagnóstico por imagen , Edad Gestacional , Femenino , Masculino , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Sustancia Blanca/embriología , Imagen de Difusión por Resonancia Magnética/métodosRESUMEN
Introduction: Essential tremor (ET) comprises motor and non-motor-related features, whereas the current neuro-pathogenetic basis is still insufficient to explain the etiologies of ET. Although cerebellum-associated circuits have been discovered, the large-scale cerebral network connectivity in ET remains unclear. This study aimed to characterize the ET in terms of functional connectivity as well as network. We hypothesized that the resting-state network (RSN) within cerebrum could be altered in patients with ET. Methods: Resting-state functional magnetic resonance imaging (fMRI) was used to evaluate the inter- and intra-network connectivity as well as the functional activity in ET and normal control. Correlation analysis was performed to explore the relationship between RSN metrics and tremor features. Results: Comparison of inter-network connectivity indicated a decreased connectivity between default mode network and ventral attention network in the ET group (p < 0.05). Differences in functional activity (assessed by amplitude of low-frequency fluctuation, ALFF) were found in several brain regions participating in various RSNs (p < 0.05). The ET group generally has higher degree centrality over normal control. Correlation analysis has revealed that tremor features are associated with inter-network connectivity (|r| = 0.135-0.506), ALFF (|r| = 0.313-0.766), and degree centrality (|r| = 0.523-0.710). Conclusion: Alterations in the cerebral network of ET were detected by using resting-state fMRI, demonstrating a potentially useful approach to explore the cerebral alterations in ET.