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OBJECTIVE: Although growing evidence suggests that perivascular space (PVS) serves as a clearance route for amyloid and tau, the association between enlarged PVS (EPVS) and Alzheimer disease is highly inconsistent across studies. As the conventional visual rating systems for EPVS were insufficient to predict amyloid/tau/neurodegeneration (A/T/N) status, we developed a new rating scale for EPVS located in the temporal lobe (T-EPVS). METHODS: EPVS located in the basal ganglia (BG-EPVS), centrum semiovale (CS-EPVS), and T-EPVS was visually rated in 272 individuals (healthy controls, n = 96; mild cognitive impairment, n = 106; dementia, n = 70) who underwent structural magnetic resonance imaging (MRI) and dual positron emission tomography scans (18 F-flortaucipir and 18 F-florbetaben). T-EPVS and BG-EPVS were defined as high degree when the counts in any hemisphere were >10, and the CS-EPVS cutoff was >20. Logistic regression models were constructed to investigate whether the regional EPVS burden was predictive of A/T/N status. The derived models were externally validated in a temporal validation cohort (n = 195) that underwent MRI studies using a different scanner. RESULTS: Compared with those with low-degree T-EPVS (23/136, 16.9%), individuals with high-degree T-EPVS/CS-EPVS but low-degree BG-EPVS were more likely to exhibit amyloid positivity (46/56, 82.1%). High-degree T-EPVS burden (odds ratio [OR] = 7.251, 95% confidence interval [CI] = 3.296-15.952) and low-degree BG-EPVS (OR = 0.241, 95% CI = 0.109-0.530) were predictive of amyloid positivity. Although high-degree T-EPVS was associated with tau positivity, the association was no longer significant after adjusting for amyloid and neurodegeneration status. INTERPRETATION: Investigating the burden and topographic distribution of EPVS including T-EPVS may be useful for predicting amyloid status, indicating that impaired perivascular drainage may contribute to cerebral amyloidosis. ANN NEUROL 2023;93:965-978.
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Amiloidosis , Disfunción Cognitiva , Humanos , Imagen por Resonancia Magnética , Amiloidosis/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Tomografía de Emisión de Positrones , Lóbulo Temporal/diagnóstico por imagenRESUMEN
BACKGROUND: Nigrosome 1 (NG1), a small cluster of dopaminergic cells in the substantia nigra and visible in the susceptibility map-weighted magnetic resonance image (SMwI), is severely affected in Parkinson's disease (PD). However, the degree of nigrostriatal degeneration according to the visibility of NG1 has not yet been well elucidated. METHODS: We consecutively recruited 138 PD and 78 non-neurodegenerative disease (non-ND) patients, who underwent both 18 F-FP-CIT positron emission tomography (PET) and SMwI. Three neurologists and one radiologist evaluated the visibility of NG1 in SMwI. The participants were thereby grouped into visible, intermediate, and non-visible groups. Nigrostriatal dopaminergic input was calculated using the specific binding ratio (SBR) of the 18 F-FP-CIT PET. We determined the threshold of regional SBR for discriminating NG1 visibility and the probability for NG1 visibility according to regional SBR. RESULTS: Visual rating of NG1 showed excellent interobserver agreements as well as high sensitivity and specificity to differentiate the PD group from the non-ND group. NG1 was visible in seven patients (5.1%) in the PD group, who had relatively short disease duration or less severe loss of striatal dopamine. The threshold of putaminal SBR reduction on the more affected side for the disappearance of NG1 was 45.5%, and the probability for NG1 visibility dropped to 50% after the reduction of putaminal SBR to 41% from the normal mean. CONCLUSIONS: Almost half loss of nigrostriatal dopaminergic input is required to dissipate the hyperintensity of NG1 on SMwI, suggesting its utility in diagnosing PD only after the onset of the motor symptoms.
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Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/complicaciones , Dopamina/metabolismo , Tropanos/metabolismo , Tomografía de Emisión de Positrones/métodos , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/metabolismo , Tomografía Computarizada de Emisión de Fotón Único/métodos , Sustancia Negra/diagnóstico por imagen , Sustancia Negra/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismoRESUMEN
Bickerstaff's brainstem encephalitis is a rare autoimmune disorder that presents with ataxia, ophthalmoplegia, disturbance of consciousness and quadriplegia. A 45-year-old man with a history of ulcerative colitis (UC) taking mesalazine (5-aminosalicylic acid) visited the emergency room presenting with ataxia, ophthalmoplegia and a progressively worsening cognitive impairment. Cerebrospinal fluid analysis showed mild elevation in protein and white blood cell count and increased intracranial pressure. Anti-GQ1b autoantibodies were found positive in the patient's serum and contrast-enhanced brain magnetic resonance imaging showed diffuse leptomeningeal enhancement and pontine lesions. Based on these findings and the patient's clinical course and history, he was diagnosed with Bickerstaff's brainstem encephalitis. Mesalazine was discontinued and high-dose steroid pulse therapy was started, followed by intravenous immunoglobulin, which resulted in gradual improvement of the neurologic symptoms. When an ulcerative colitis patient presents with progressive cognitive impairment, quadriplegia and disturbance of consciousness and gait, Bickerstaff brainstem encephalitis should be considered in the differential diagnosis and prompt immunotherapy may lead to favorable prognosis.
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Enfermedades Autoinmunes del Sistema Nervioso , Colitis Ulcerosa , Encefalitis , Oftalmoplejía , Masculino , Humanos , Persona de Mediana Edad , Tronco Encefálico/diagnóstico por imagen , Tronco Encefálico/patología , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/patología , Mesalamina , Encefalitis/complicaciones , Encefalitis/diagnóstico , Cuadriplejía , Ataxia/complicaciones , GangliósidosRESUMEN
BACKGROUND: Clear guidelines for a patient with suspected COVID-19 infection are unavailable. Many countries rely on assessments through a national hotline or telecommunications, but this only adds to the burden of an already overwhelmed health care system. In this study, we developed an algorithm and a web application to help patients get screened. OBJECTIVE: This study aims to aid the general public by developing a web-based application that helps patients decide when to seek medical care during a novel disease outbreak. METHODS: The algorithm was developed via consultations with 6 physicians who directly screened, diagnosed, and/or treated patients with COVID-19. The algorithm mainly focused on when to test a patient in order to allocate limited resources more efficiently. The application was designed to be mobile-friendly and deployed on the web. We collected the application usage pattern data from March 1 to March 27, 2020. We evaluated the association between the usage pattern and the numbers of COVID-19 confirmed, screened, and mortality cases by access location and digital literacy by age group. RESULTS: The algorithm used epidemiological factors, presence of fever, and other symptoms. In total, 83,460 users accessed the application 105,508 times. Despite the lack of advertisement, almost half of the users accessed the application from outside of Korea. Even though the digital literacy of the 60+ years age group is half of that of individuals in their 50s, the number of users in both groups was similar for our application. CONCLUSIONS: We developed an expert-opinion-based algorithm and web-based application for screening patients. This innovation can be helpful in circumstances where information on a novel disease is insufficient and may facilitate efficient medical resource allocation.
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Infecciones por Coronavirus/diagnóstico , Tamizaje Masivo/métodos , Tamizaje Masivo/estadística & datos numéricos , Aplicaciones Móviles , Neumonía Viral/diagnóstico , Autocuidado/métodos , Autocuidado/estadística & datos numéricos , Adulto , Anciano , Algoritmos , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/epidemiología , Brotes de Enfermedades , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/epidemiología , Derivación y Consulta , República de Corea/epidemiología , SARS-CoV-2 , Adulto JovenRESUMEN
Background: Degeneration of cholinergic basal forebrain (BF) neurons characterizes Alzheimer's disease (AD). However, what role the BF plays in the dynamics of AD pathophysiology has not been investigated precisely. Objective: To investigate the baseline and longitudinal roles of BF along with core neuropathologies in AD. Methods: In this retrospective cohort study, we enrolled 113 subjects (38 amyloid [Aß]-negative cognitively unimpaired, 6 Aß-positive cognitively unimpaired, 39 with prodromal AD, and 30 with AD dementia) who performed brain MRI for BF volume and cortical thickness, 18F-florbetaben PET for Aß, 18F-flortaucipir PET for tau, and detailed cognitive testing longitudinally. We investigated the baseline and longitudinal association of BF volume with Aß and tau standardized uptake value ratio and cognition. Results: Cross-sectionally, lower BF volume was not independently associated with higher cortical Aß, but it was associated with tau burden. Tau burden in the orbitofrontal, insular, lateral temporal, inferior temporo-occipital, and anterior cingulate cortices were associated with progressive BF atrophy. Lower BF volume was associated with faster Aß accumulation, mainly in the prefrontal, anterior temporal, cingulate, and medial occipital cortices. BF volume was associated with progressive decline in language and memory functions regardless of baseline Aß and tau burden. Conclusions: Tau deposition affected progressive BF atrophy, which in turn accelerated amyloid deposition, leading to a vicious cycle. Also, lower baseline BF volume independently predicted deterioration in cognitive function.
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Enfermedad de Alzheimer , Péptidos beta-Amiloides , Prosencéfalo Basal , Cognición , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Proteínas tau , Humanos , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/diagnóstico por imagen , Masculino , Femenino , Anciano , Proteínas tau/metabolismo , Prosencéfalo Basal/patología , Prosencéfalo Basal/metabolismo , Prosencéfalo Basal/diagnóstico por imagen , Péptidos beta-Amiloides/metabolismo , Estudios Retrospectivos , Cognición/fisiología , Estudios Transversales , Anciano de 80 o más Años , Estudios Longitudinales , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estudios de CohortesRESUMEN
BACKGROUND: Parkinson's disease (PD) manifests as a wide variety of clinical phenotypes and its progression varies greatly. However, the factors associated with different disease progression remain largely unknown. METHODS: In this retrospective cohort study, we enrolled 113 patients who underwent 18F-FP-CIT PET scan twice. Given the negative exponential progression pattern of dopamine loss in PD, we applied the natural logarithm to the specific binding ratio (SBR) of two consecutive 18F-FP-CIT PET scans and conducted linear mixed model to calculate individual slope to define the progression rate of nigrostriatal degeneration. We investigated the clinical and dopamine transporter (DAT) availability patterns associated with the progression rate of dopamine depletion in each striatal sub-region. RESULTS: More symmetric parkinsonism, the presence of dyslipidemia, lower K-MMSE total score, and lower anteroposterior gradient of the mean putaminal SBR were associated with faster progression rate of dopamine depletion in the caudate nucleus. More symmetric parkinsonism and lower anteroposterior gradient of the mean putaminal SBR were associated with faster depletion of dopamine in the anterior putamen. Older age at onset, more symmetric parkinsonism, the presence of dyslipidemia, and lower anteroposterior gradient of the mean putaminal SBR were associated with faster progression rate of dopamine depletion in the posterior putamen. Lower striatal mean SBR predicted the development of LID, while lower mean SBR in the caudate nuclei predicted the development of dementia. DISCUSSION: Our results suggest that the evaluation of baseline clinical features and patterns of DAT availability can predict the progression of PD and its prognosis.
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Cuerpo Estriado , Progresión de la Enfermedad , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Enfermedad de Parkinson , Tomografía de Emisión de Positrones , Humanos , Masculino , Femenino , Anciano , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/complicaciones , Estudios Retrospectivos , Persona de Mediana Edad , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/metabolismo , Cuerpo Estriado/patología , Tropanos , Sustancia Negra/diagnóstico por imagen , Sustancia Negra/metabolismo , Sustancia Negra/patologíaRESUMEN
We propose a novel blood biomarker detection method that uses miRNA super-resolution imaging to enable the early diagnosis of Alzheimer's disease (AD). Here, we report a singlemolecule detection method for visualizing disease-specific miRNA in tissue from an AD mice model, and peripheral blood mononuclear cells (PBMCs) from AD patients. Using optimized Magnified Analysis of Proteome (MAPs), we confirmed that five miRNAs contribute to neurodegenerative disease in the brain hippocampi of 5XFAD and wild-type mice. We also assessed PBMCs isolated from the whole blood of AD patients and a healthy control group, and subsequently analyzed those samples using miRNA super-resolution imaging. We detected more miR-200a-3p expression in the cornu ammonis 1 and dentate gyrus regions of 3 month-old 5XFAD mice than in wild-type mice. Additionally, miRNA super-resolution imaging of blood provides AD diagnosis platform for studying miRNA regulation inside cells at the single molecule level. Our results present a potential liquid biopsy method that could improve the diagnosis of early stage AD and other diseases. [BMB Reports 2023; 56(3): 190-195].
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Enfermedad de Alzheimer , MicroARNs , Enfermedades Neurodegenerativas , Ratones , Animales , MicroARNs/genética , MicroARNs/metabolismo , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Enfermedades Neurodegenerativas/metabolismo , Leucocitos Mononucleares/metabolismo , Hipocampo/diagnóstico por imagen , Hipocampo/metabolismoRESUMEN
BACKGROUND AND OBJECTIVES: Patients with Alzheimer disease (AD) frequently suffer from various sleep disturbances. However, how sleep disturbance is associated with AD and its progression remains poorly investigated. We investigated the association of total sleep time with brain amyloid and tau burden, cortical atrophy, cognitive dysfunction, and their longitudinal changes in the AD spectrum. METHODS: In this retrospective cohort study, we enrolled participants on the AD spectrum who were positive on 18F-florbetaben (FBB) PET. All participants underwent the Pittsburgh Sleep Quality Index, brain MRI, FBB PET, 18F-flortaucipir (FTP) PET, and detailed neuropsychological testing. In addition, a subset of participants completed follow-up assessments. We analyzed the association of total sleep time with the baseline and longitudinal FBB-standardized uptake value ratio (SUVR), FTP-SUVR, cortical thickness, and cognitive domain composite scores. RESULTS: We examined 138 participants on the AD spectrum (15 with preclinical AD, 62 with prodromal AD, and 61 with AD dementia; mean age 73.4 ± 8.0 years; female 58.7%). Total sleep time was longer in the AD dementia group (7.4 ± 1.6 hours) compared with the preclinical (6.5 ± 1.4 hours; p = 0.026) and prodromal groups (6.6 ± 1.4 hours; p = 0.001), whereas other sleep parameters did not differ between groups. Longer total sleep time was not associated with amyloid accumulation but rather with tau accumulation, especially in the amygdala, hippocampus, basal forebrain, insular, cingulate, occipital, inferior temporal cortices, and precuneus. Longer total sleep time predicted faster tau accumulation in Braak regions V-VI (ß = 0.016, p = 0.007) and disease progression to mild cognitive impairment or dementia (hazard ratio = 1.554, p = 0.024). Longer total sleep time was also associated with memory deficit (ß = -0.19, p = 0.008). DISCUSSION: Prolonged total sleep time was associated with tau accumulation in sleep-related cortical and subcortical areas as well as memory dysfunction. It also predicted faster disease progression with tau accumulation. Our study highlights the clinical importance of assessing total sleep time as a marker for disease severity and prognosis in the AD spectrum.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Amiloide/metabolismo , Péptidos beta-Amiloides/metabolismo , Proteínas Amiloidogénicas , Atrofia/patología , Encéfalo/patología , Progresión de la Enfermedad , Tomografía de Emisión de Positrones , Estudios Retrospectivos , Sueño , Proteínas tau/metabolismo , MasculinoRESUMEN
Makorin ring finger protein 3 (MKRN3) was identified as an inhibitor of puberty initiation with the report of loss-of-function mutations in association with central precocious puberty. Consistent with this inhibitory role, a prepubertal decrease in Mkrn3 expression was observed in the mouse hypothalamus. Here, we investigated the mechanisms of action of MKRN3 in the central regulation of puberty onset. We showed that MKRN3 deletion in hypothalamic neurons derived from human induced pluripotent stem cells was associated with significant changes in expression of genes controlling hypothalamic development and plasticity. Mkrn3 deletion in a mouse model led to early puberty onset in female mice. We found that Mkrn3 deletion increased the number of dendritic spines in the arcuate nucleus but did not alter the morphology of GnRH neurons during postnatal development. In addition, we identified neurokinin B (NKB) as an Mkrn3 target. Using proteomics, we identified insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) as another target of MKRN3. Interactome analysis revealed that IGF2BP1 interacted with MKRN3, along with several members of the polyadenylate-binding protein family. Our data show that one of the mechanisms by which MKRN3 inhibits pubertal initiation is through regulation of prepubertal hypothalamic development and plasticity, as well as through effects on NKB and IGF2BP1.
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Células Madre Pluripotentes Inducidas , Pubertad Precoz , Humanos , Femenino , Ratones , Animales , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Hipotálamo/metabolismo , Pubertad , Hormona Liberadora de Gonadotropina/metabolismo , Pubertad Precoz/genética , Pubertad Precoz/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
INTRODUCTION: Almost half of the nigral neurons are already lost during the preclinical period of Parkinson's disease (PD), and then the speed of neuronal loss is slowly attenuated during the subsequent progression. We sought to establish long-term temporal trajectory models for the dopaminergic input to the striatal subregions and a 4D-temporal trajectory model for the dopamine transporter positron emission tomography (PET). METHODS: We selected 83 patients in PD spectrum who underwent dopamine transporter PET scan twice and 71 age-matched healthy controls. We created temporal trajectories of specific binding ratios of the striatal subregions by integrating function between baseline values and their annual change rates and also created 4D-temporal trajectory model by applying the same method for each striatal voxel. Using the PET data of additional 100 PD patients, we estimated an individual time point in the 4D-temporal trajectory model for the validation. RESULTS: Degenerative loss of striatal dopaminergic input first appeared in the posterior dorsal putamen in the more affected side at 14.4 years before the clinical onset, and subsequently in the posterior ventral and anterior putamen, and finally in the caudate. The time delay between the initiation of dopaminergic loss in the more and less affected posterior dorsal putamen was 6.1 years. The estimated individual time points within the entire disease course were correlated with the motor severity. CONCLUSION: Our temporal trajectory model demonstrated a sequential loss of dopaminergic input in the striatal subregions in PD and may be beneficial for the evaluation of individual status of disease progression.
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Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Enfermedad de Parkinson , Humanos , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Tomografía de Emisión de Positrones/métodosRESUMEN
BACKGROUND: The clinical features of Alzheimer's disease (AD) vary substantially depending on whether the onset of cognitive deficits is early or late. The amount and distribution patterns of tau pathology are thought to play a key role in the clinical characteristics of AD, which spreads throughout the large-scale brain network. Here, we describe the differences between tau-spreading processes in early- and late-onset symptomatic individuals on the AD spectrum. METHODS: We divided 74 cognitively unimpaired (CU) and 68 cognitively impaired (CI) patients receiving 18F-flortaucipir positron emission tomography scans into two groups by age and age at onset. Members of each group were arranged in a pseudo-longitudinal order based on baseline tau pathology severity, and potential interregional tau-spreading pathways were defined following the order using longitudinal tau uptake. We detected a multilayer community structure through consecutive tau-spreading networks to identify spatio-temporal changes in the propagation hubs. RESULTS: In each group, ordered tau-spreading networks revealed the stage-dependent dynamics of tau propagation, supporting distinct tau accumulation patterns. In the young CU/early-onset CI group, tau appears to spread through a combination of three independent communities with partially overlapped territories, whose specific driving regions were the basal temporal regions, left medial and lateral temporal regions, and left parietal regions. For the old CU/late-onset CI group, however, continuation of major communities occurs in line with the appearance of hub regions in the order of bilateral entorhinal cortices, parahippocampal and fusiform gyri, and lateral temporal regions. CONCLUSION: Longitudinal tau propagation depicts distinct spreading pathways of the early- and late-onset AD spectrum characterized by the specific location and appearance period of several hub regions that dominantly provide tau.
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Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Disfunción Cognitiva/metabolismo , Humanos , Imagen por Resonancia Magnética/métodos , Tomografía de Emisión de Positrones/métodos , Proteínas tau/metabolismoRESUMEN
Despite recent studies suggesting a declining incidence and prevalence of dementia on a global scale, epidemiologic results with respect to Alzheimer's disease (AD) are lacking due to the methodological limitations inherent to conducting large-scale cohort investigations of this topic. The aim of the current study was to investigate the incidence and prevalence of AD in Korea. We conducted a secondary analysis within the National Health Insurance System (NHIS) database, a unique resource that reports medical information for the entire Korean population. AD diagnoses as well as evaluations of vascular risks were defined based on International Statistical Classification of Diseases (ICD-10) codes along with prescription records. The cut-off age for diagnosing AD was defined as the age of the patient's highest Youden index. In this study, the incidence and prevalence of AD in the Korean population aged 40 years or older showed an overall increase between 2006 and 2015. Although both older and younger age groups showed an increase in the incidence and prevalence of AD, the highest increase was observed in older age groups. Based on the highest Youden's index value (sensitivity + specificity - 1), the cut-off value for the diagnosis of AD was 69 years with an area under the curve (AUC) of 0.92. We found that the incidence of AD was higher in individuals with underlying vascular risks. However, in recent years, the prevalence of AD was conversely found to be lower in individuals with hypertension or dyslipidemia. Despite efforts toward reducing the number of AD cases through educational, policy, and various public health and preventive medicine interventions, the incidence and prevalence of AD continues to grow in Korea. Efforts aimed at early diagnosis and the modification of underlying risks may be critical to reducing the socioeconomic burden of AD.
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Gonadotropin-releasing hormone (GnRH) regulates gonadal function via its stimulatory effects on gonadotropin production by pituitary gonadotrope cells. GnRH is released from the hypothalamus in pulses and GnRH pulse frequency differentially regulates follicle-stimulating hormone (FSH) and luteinizing hormone (LH) synthesis and secretion. The GnRH receptor (GnRHR) is a G protein-coupled receptor that canonically activates Gαâq/11-dependent signaling on ligand binding. However, the receptor can also couple to Gαâs and in vitro data suggest that toggling between different G proteins may contribute to GnRH pulse frequency decoding. For example, as we show here, knockdown of Gαâs impairs GnRH-stimulated FSH synthesis at low- but not high-pulse frequency in a model gonadotrope-derived cell line. We next used a Cre-lox conditional knockout approach to interrogate the relative roles of Gαâq/11 and Gαâs proteins in gonadotrope function in mice. Gonadotrope-specific Gαâq/11 knockouts exhibit hypogonadotropic hypogonadism and infertility, akin to the phenotypes seen in GnRH- or GnRHR-deficient mice. In contrast, under standard conditions, gonadotrope-specific Gαâs knockouts produce gonadotropins at normal levels and are fertile. However, the LH surge amplitude is blunted in Gαâs knockout females and postgonadectomy increases in FSH and LH are reduced both in males and females. These data suggest that GnRH may signal principally via Gαâq/11 to stimulate gonadotropin production, but that Gαâs plays important roles in gonadotrope function in vivo when GnRH secretion is enhanced.
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Cromograninas/fisiología , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/fisiología , Subunidades alfa de la Proteína de Unión al GTP Gs/fisiología , Gonadotrofos/metabolismo , Gonadotropinas/metabolismo , Animales , Castración , Línea Celular , Cromograninas/genética , Femenino , Fertilidad/genética , Fertilidad/fisiología , Hormona Folículo Estimulante de Subunidad beta/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Subunidades alfa de la Proteína de Unión al GTP Gs/genética , Regulación de la Expresión Génica/fisiología , Hormona Liberadora de Gonadotropina/fisiología , Gonadotropinas/genética , Células HEK293 , Humanos , Hormona Luteinizante/genética , Hormona Luteinizante/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores LHRH/genética , Receptores LHRH/fisiología , Maduración Sexual , Transducción de Señal/fisiologíaRESUMEN
Full dynamics of biofluid biomarkers have been unknown in patients with Parkinson's disease (PD). Using data from 396 PD patients and 182 controls in the Parkinson's Progression Markers Initiative (PPMI) database, we estimated long-term temporal trajectories of CSF α-synuclein (α-syn), amyloid-ß (Aß), total tau (t-tau), phosphorylated tau (p-tau) and serum neurofilament light chain (NfL) by integrating function between the baseline levels and annual changes. At baseline, PD patients showed lower CSF α-syn, Aß, t-tau and p-tau levels than those of the controls. In all PD patients, CSF α-syn and Aß decreased in a negative exponential pattern before the onset of motor symptoms, whereas CSF t-tau and p-tau, and serum NfL increased. Patients with cognitive impairment exhibited faster decline of Aß and α-syn and faster rise of t-tau, p-tau and NfL, when compared to those without. Similarly, low Aß group showed earlier decline of α-syn, faster rise of t-tau, p-tau and NfL, and faster decline of cognitive performances, when compared to high Aß group. Our results suggest that longitudinal changes in biomarkers can be influenced by cognitive impairment and Aß burden at baseline. PD patients with Aß pathology may be associated with early appearance of α-synuclein pathology, rapid progression of axonal degeneration and neurodegeneration, and consequently greater cognitive decline.
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Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Enfermedad de Parkinson/psicología , alfa-Sinucleína/líquido cefalorraquídeo , Proteínas tau/líquido cefalorraquídeo , Anciano , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Regulación de la Expresión Génica , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/líquido cefalorraquídeo , Enfermedad de Parkinson/metabolismo , FosforilaciónRESUMEN
To estimate dopaminergic dysfunction in patients with Parkinson disease (PD) during the premotor stage and to investigate the effect of genetic factors on the trajectories. Using longitudinal dopamine transporter single-photon emission computed tomography data from 367 sporadic PD (sPD), 72 LRRK2 (G2019S), and 39 GBA (N370S) PD patients in the Parkinson's Progression Markers Initiative (PPMI) study, we estimated the temporal trajectories of putaminal-specific binding ratios using an integrating function between baseline values and their annual change rates. In order to test reproducibility, we computed another trajectory for sPD using positron emission tomography data of 38 sPD patients at Gangnam Severance Hospital (GSH). Temporal trajectories of sPD were compared between the groups separated by age at onset (AAO) and polygenic load for common PD risk variants, and also compared with genetic PD. sPD patients in both the PPMI and GSH cohorts showed similar onset of dopaminergic degeneration around 10 years before motor onset. Early-onset PD patients exhibited later onset of degeneration and a faster decline in dopaminergic activity during the premotor period than late-onset patients. sPD patients with high polygenic load were associated with earlier onset and slower progression of dopaminergic dysfunction. Compared to the sPD and LRRK2 PD groups, GBA PD patients exhibited faster deterioration of dopaminergic function during the premotor stage. Dopaminergic dysfunction in PD appears to start about 10 years before motor onset. Genetic factors may be contributing to the heterogeneity of dopaminergic deterioration during the premotor stage.
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A critical body weight is necessary for pubertal development, an effect mediated in part by leptin. The potential regulation by leptin of Makorin Ring Finger Protein 3 (MKRN3), in which loss-of-function mutations are the most common genetic cause of central precocious puberty, has not been previously explored. In mice, expression of Mkrn3 in the hypothalamic arcuate nucleus is high early in life and declines before the onset of puberty. Therefore, we aimed to explore if leptin contributes to the decrease in hypothalamic Mkrn3 mRNA levels observed in mice during pubertal development. We first used a leptin-deficient (ob/ob) mouse model. Mkrn3 mRNA levels in the mediobasal hypothalamus (MBH), which includes the arcuate nucleus, and in the preoptic area (POA), both showed a significant decrease with age from postnatal day (PND) 12 to PND30 in ob/ob mice in both males and females, similar to that observed in wild-type mice. To further explore the effects of leptin on Mkrn3 expression, we exposed prepubertal wild-type mice to high levels of leptin from age PND9-12, which did not result in any significant difference in Mkrn3 expression levels in either the MBH or POA. In summary, regulation of Mkrn3 expression by leptin was not observed in either the MBH or the POA, 2 hypothalamic sites important for pubertal maturation. These data suggest that the decline in Mkrn3 at the onset of puberty may occur independently of leptin and support our hypothesis that MKRN3 is a bona fide controller of puberty initiation.
RESUMEN
According to the result of retrospective studies for patients who have not taken medical treatment, most patients experience late enophthalmos and perceive their facial asymmetry. Thus, correct diagnosis method and concrete operative indication were required for medial orbital wall fracture. Retrospective investigation on all patients with facial trauma, who had visited the emergency room between January 1, 2000 and December 31, 2006, was made. Height and longitudinal length of the defect were obtained, and computed tomographic scan of the defect area was obtained. The degree of enophthalmos was measured, and investigation on enophthalmos and presence of facial asymmetry perceived by the patients was made. When the defect area of medial orbital wall fracture was 0.55 cm, late enophthalmos of 1 mm occurred, and patients with late enophthalmos of 1 mm or more perceived their enophthalmos and facial asymmetry. In conclusion, medial orbital wall fracture whose defect area is 0.55 cm or more requires operation.
Asunto(s)
Enoftalmia/etiología , Fracturas Orbitales/complicaciones , Cefalometría , Enoftalmia/psicología , Hueso Etmoides/lesiones , Asimetría Facial/etiología , Asimetría Facial/psicología , Hueso Frontal/lesiones , Humanos , Luxaciones Articulares/clasificación , Luxaciones Articulares/complicaciones , Fracturas Maxilares/clasificación , Órbita/lesiones , Fracturas Orbitales/clasificación , Estudios Retrospectivos , Autoimagen , Fracturas Craneales/clasificación , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: Patients with drug-induced parkinsonism (DIP) may have nigrostriatal dopaminergic degeneration. We studied the clinical features that may indicate nigrostriatal dopaminergic degeneration in patients with DIP. METHODS: Forty-one DIP patients were classified into normal and abnormal [18F] FP-CIT scan groups. Differences in 32 clinical features and drug withdrawal effects were studied. RESULTS: Twenty-eight patients had normal (Group I) and 13 patients had abnormal (Group II) scans. Eight patients of Group I, but none of Group II, had taken calcium channel blockers (p = 0.040). Three patients of Group I and six of Group II had hyposmia (p = 0.018). After drug withdrawal, Group I showed greater improvement in Unified Parkinson's Disease Rating Scale total motor scores and subscores for bradykinesia and tremors than Group II. Only hyposmia was an independent factor associated with abnormal scans, but it had suboptimal sensitivity. CONCLUSION: None of the clinical features were practical indicators of nigrostriatal dopaminergic degeneration in patients with DIP.