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INTRODUCTION: We investigated the effectiveness of lenvatinib (LEN) after disease progression following first-line treatment with atezolizumab plus bevacizumab (Atez/Bev) in patients with unresectable hepatocellular carcinoma (HCC). METHODS: One hundred and ten HCC patients treated with Atez/Bev as first-line systemic chemotherapy were enrolled and underwent dynamic computerized tomography/magnetic resonance imaging to determine the treatment response. We evaluated the treatment efficacy and prognosis after second-line LEN treatment, especially in elderly patients. RESULTS: Of the 110 study patients, 88 patients (80%) were determined to have progressive disease (PD) during the observation periods, and 40 patients received second-line LEN therapy. The 40 patients included 13 patients who were unable to continue LEN until the initial evaluation due to adverse events (AE). The 27 patients who were able to continue LEN therapy (Group A) were significantly younger at initiation of Atez/Bev than those who could not continue (71 vs. 77 years old, p = 0.013). Comparing the OS and PFS between Group A and 44 patients that included 13 patients who were unable to continue LEN and 31 patients did not receive the second-line treatment (Group B), the former had significantly better OS than Group B (31.1 vs. 17.8 months, p = 0.035). CONCLUSIONS: The tolerability of second-line LEN therapy was lower in elderly patients, and the OS from the start of Atez/Bev therapy was different depending on the tolerability of second-line LEN therapy.
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Spinal cord injury (SCI) is damage or trauma to the spinal cord, which often results in loss of function, sensation, or mobility below the injury site. Transcranial direct current stimulation (tDCS) is a non-invasive and affordable brain stimulation technique used to modulate neuronal circuits, which changes the morphology and activity of microglia in the cerebral cortex. However, whether similar morphological changes can be observed in the spinal cord remains unclear. Therefore, we evaluated neuronal population activity in layer 5 (L5) of M1 following SCI and investigated whether changes in the activities of L5 neurons affect microglia-axon interactions using C57BL/6J mice. We discovered that L5 of the primary motor cortex (corticospinal neurons) exhibited reduced synchronized activity after SCI that correlates with microglial morphology, which was recovered using tDCS. This indicates that tDCS promotes changes in the morphological properties and recovery of microglia after SCI. Combining immunotherapy with tDCS may be effective in treating SCI.
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Camundongos Endogâmicos C57BL , Microglia , Córtex Motor , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal , Estimulação Transcraniana por Corrente Contínua , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/fisiopatologia , Animais , Microglia/metabolismo , Estimulação Transcraniana por Corrente Contínua/métodos , Camundongos , Córtex Motor/fisiopatologia , Modelos Animais de Doenças , Masculino , Medula Espinal/fisiopatologia , Medula Espinal/patologia , FemininoRESUMO
OBJECTIVE: Ikigai is a Japanese concept of a life worth living and related to eudaimonic well-being. Supporting the pursuit of ikigai is of central importance to recovery-oriented psychiatric rehabilitation for people with serious mental illnesses (SMI). While research suggests that work, leisure, and social relationships are potential sources of ikigai, people with SMI have restricted access to these as they encounter systemic barriers to participating in such activities. This study investigated how people with SMI in Japan pursued sources of ikigai in the face of barriers. METHODS: A total of 21 community-living individuals who had SMI and were recruited from community psychiatric rehabilitation service providers in Japan participated in the study. Photo-elicitation interviews were conducted, and the interview transcripts were analyzed using reflexive thematic analysis. RESULTS: Three themes were generated: (a) self-determination as a key to ikigai, (b) explorations needed to identify sources of ikigai, and (c) navigating the challenges to engage in the explorations. It was found that a self-determined activity tends to be a source of ikigai. However, participants had to grapple with challenges because identifying a source of ikigai involved the exploration of their personal interests, and the exploration could not be continued without managing the stigma of mental illness. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Results suggest that ikigai cannot be achieved instantly. To achieve eudaimonic well-being outcomes, psychiatric rehabilitation professionals should allow consumers to choose activities based on their personal interests and encourage them to try out various activities while they provide continued support to overcome stigma. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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17O-labeled water is a T2-shortening contrast agent used in proton MRI and is a promising method for visualizing cerebrospinal fluid (CSF) dynamics because it provides long-term tracking of water molecules. However, various external factors reduce the accuracy of 17O-concentration measurements using conventional signal-intensity-based methods. In addition, T2 mapping, which is expected to provide a stable assessment, is generally limited to temporal-spatial resolution. We developed the T2-prepared based on T2 mapping used in cardiac imaging to adapt to long T2 values and tested whether it could accurately measure 17O-concentration in the CSF using a phantom. The results showed that 17O-concentration in a fluid mimicking CSF could be evaluated with an accuracy comparable to conventional T2-mapping (Carr-Purcell-Meiboom-Gill multi-echo spin-echo method). This method allows 17O-imaging with a high temporal resolution and stability in proton MRI. This imaging technique may be promising for visualizing CSF dynamics using 17O-labeled water.
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OBJECTIVE: To evaluate in-hospital fees and surgical outcomes of robot-assisted radical cystectomy (RARC), laparoscopic radical cystectomy (LRC) and open radical cystectomy (ORC) using a Japanese nationwide database. METHODS: All data were obtained from the Diagnosis Procedure Combination database between April 2020 and March 2022. Basic characteristics and perioperative indicators, including in-hospital fees, were compared among the RARC, LRC and ORC groups. Propensity score-matched comparisons were performed to assess the differences between RARC and ORC. RESULTS: During the study period, 2931, 1311 and 2435 cases of RARC, LRC and ORC were identified, respectively. The RARC group had the lowest in-hospital fee (median: 2.38 million yen), the shortest hospital stay (26 days) and the lowest blood transfusion rate (29.5%), as well as the lowest complication rate (20.9%), despite having the longest anesthesia time (569 min) among the three groups (all P < 0.01). The outcomes of LRC were comparable with those of RARC, and the differences in these indicators between the RARC and ORC groups were greater than those between the RARC and LRC groups. In propensity score-matched comparisons between the RARC and ORC groups, the differences in the indicators remained significant (all P < 0.01), with an ~50 000 yen difference in in-hospital fees. CONCLUSIONS: RARC and LRC were considered to be more cost-effective surgeries than ORC due to their superior surgical outcomes and comparable surgical fees in Japan. The widespread adoption of RARC and LRC is expected to bring economic benefits to Japanese society.
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Cistectomia , Laparoscopia , Procedimentos Cirúrgicos Robóticos , Neoplasias da Bexiga Urinária , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cistectomia/economia , Cistectomia/métodos , População do Leste Asiático , Japão , Laparoscopia/economia , Tempo de Internação/estatística & dados numéricos , Tempo de Internação/economia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/economia , Pontuação de Propensão , Procedimentos Cirúrgicos Robóticos/economia , Resultado do Tratamento , Neoplasias da Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/economia , Honorários MédicosRESUMO
Bruton's tyrosine kinase (BTK), a member of the TEC family of kinases, is an essential effector of B-cell receptor (BCR) signaling. Chronic activation of BTK-mediated BCR signaling is a hallmark of many hematological malignancies, which makes it an attractive therapeutic target. Pharmacological inhibition of BTK enzymatic function is now a well-proven strategy for the treatment of patients with these malignancies. We report the discovery and characterization of NX-2127, a BTK degrader with concomitant immunomodulatory activity. By design, NX-2127 mediates the degradation of transcription factors IKZF1 and IKZF3 through molecular glue interactions with the cereblon E3 ubiquitin ligase complex. NX-2127 degrades common BTK resistance mutants, including BTKC481S. NX-2127 is orally bioavailable, exhibits in vivo degradation across species, and demonstrates efficacy in preclinical oncology models. NX-2127 has advanced into first-in-human clinical trials and achieves deep and sustained degradation of BTK following daily oral dosing at 100 mg.
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Inibidores de Proteínas Quinases , Proteínas Tirosina Quinases , Humanos , Tirosina Quinase da Agamaglobulinemia , Inibidores de Proteínas Quinases/efeitos adversos , Transdução de SinaisRESUMO
INTRODUCTION: Atezolizumab plus bevacizumab (Atez/Bev) is the preferred treatment for advanced hepatocellular carcinoma (HCC). However, biomarkers of therapeutic efficacy have remained unclear. We took a retrospective approach to explore the role of prognostic nutritional index (PNI) for predicting the outcomes of Atez/Bev treatment. METHODS: One hundred 25 HCC patients were enlisted; these patients received Atez/Bev treatment and underwent dynamic computerized tomography/magnetic resonance imaging to determine the treatment response on at least one occasion between October 2020 and January 2023, and their PNI before treatment and at the beginning of the second cycle (PNI-2c) was evaluated. RESULTS: During the initial evaluation, 2 (2%), 28 (22%), 70 (56%), and 25 (20%) patients exhibited a complete response, partial response, stable disease, and progressive disease (PD), respectively. Patients with non-PD tended to have higher PNI at baseline and PNI-2c than those with PD (p = 0.245 and 0.122, respectively), with optimal baseline PNI and PNI-2c cut-off values of 42.6 and 40.4, respectively. PNI at baseline could not be used to predict overall survival (OS) or progression-free survival (PFS). However, PNI-2c predicted OS and PFS (PNI-2c ≥ 40.4 vs. < 40.4: 25.3 vs. 16.2 months, p = 0.008 for OS; 12.7 vs. 8.4 months, p = 0.036 for PFS). A multivariate analysis showed a significant association between PNI-2c and OS. CONCLUSIONS: PNI-2c is a predictor of prognosis in HCC patients treated with Atez/Bev therapy.
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Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Bevacizumab , Carcinoma Hepatocelular , Neoplasias Hepáticas , Avaliação Nutricional , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Masculino , Feminino , Bevacizumab/uso terapêutico , Bevacizumab/administração & dosagem , Pessoa de Meia-Idade , Anticorpos Monoclonais Humanizados/uso terapêutico , Prognóstico , Estudos Retrospectivos , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , AdultoRESUMO
OBJECTIVE: We evaluated remission rates and their relationship with baseline characteristics in patients with rheumatoid arthritis treated with the oral Janus kinase inhibitor peficitinib. METHODS: This post hoc analysis of data from two Phase 3 studies (RAJ3 and RAJ4) of peficitinib (100 and 150 mg/day) in Asian rheumatoid arthritis patients investigated clinical disease activity index (CDAI) remission and low disease activity rates from baseline to Week 52. CDAI, Health Assessment Questionnaire-Disability Index, and van der Heijde-modified total Sharp score remission/low disease activity rates at Week 52 were evaluated among patients achieving CDAI remission at Weeks 12/28. Logistic regression analyses explored the relationship between baseline characteristics and CDAI remission/low disease activity rates. RESULTS: CDAI remission rates increased over time in a dose-dependent manner in both peficitinib-treated groups. Most patients achieving CDAI remission at Weeks 12/28 also achieved remission at Week 52. Following the multivariate analysis of demographic and baseline characteristics, factors associated with the achievement of CDAI remission at Week 28 included male sex, low baseline prednisone dose (RAJ3 only), and low baseline Disease Activity Score 28-C-reactive protein (RAJ4 only). CONCLUSIONS: Peficitinib demonstrated persistent efficacy in clinical remission to Week 52. Baseline characteristics associated with CDAI remission were mostly consistent with previous studies using other disease-modifying antirheumatic drugs.
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Adamantano/análogos & derivados , Antirreumáticos , Artrite Reumatoide , Niacinamida/análogos & derivados , Humanos , Masculino , Japão , Resultado do Tratamento , Índice de Gravidade de Doença , Artrite Reumatoide/tratamento farmacológico , Antirreumáticos/efeitos adversos , Indução de RemissãoRESUMO
ABSTRACT: Magnetic resonance imaging (MRI) is a crucial imaging technique for visualizing water in living organisms. Besides proton MRI, which is widely available and enables direct visualization of intrinsic water distribution and dynamics in various environments, MR-WTI (MR water tracer imaging) using 17 O-labeled water has been developed, benefiting from the many advancements in MRI software and hardware that have substantially improved the signal-to-noise ratio and made possible faster imaging. This cutting-edge technique allows the generation of novel and valuable images for clinical use. This review elucidates the studies related to MRI water tracer techniques centered around 17 O-labeled water, explaining the fundamental principles of imaging and providing clinical application examples. Anticipating continued progress in studies involving isotope-labeled water, this review is expected to contribute to elucidating the pathophysiology of various diseases related to water dynamics abnormalities and establishing novel imaging diagnostic methods for associated diseases.
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Imageamento por Ressonância Magnética , Software , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodosRESUMO
Microglial processes survey the brain parenchyma, but it is unknown whether this process is influenced by the cell activity of nearby microglia under physiological conditions. Herein, we showed that microglial process dynamics differ when facilitated by astrocytic activity and pre-synaptic activity. The results revealed distinct microglial process dynamics associated with the activity of other brain cells.
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Astrócitos , Microglia , Humanos , Microglia/fisiologia , EncéfaloRESUMO
The recent outbreaks of Marburg virus disease (MVD) in Guinea, Ghana, Equatorial Guinea, and Tanzania, none of which had reported previous outbreaks, imply increasing risks of spillover of the causative viruses, Marburg virus (MARV) and Ravn virus (RAVV), from their natural host animals. These outbreaks have emphasized the need for the development of rapid diagnostic tests for this disease. Using monoclonal antibodies specific to the viral nucleoprotein, we developed an immunochromatography (IC) assay for the rapid diagnosis of MVD. The IC assay was found to be capable of detecting approximately 102-4 50% tissue culture infectious dose (TCID50)/test of MARV and RAVV in the infected culture supernatants. We further confirmed that the IC assay could detect the MARV and RAVV antigens in the serum samples from experimentally infected nonhuman primates. These results indicate that the IC assay to detect MARV can be a useful tool for the rapid point-of-care diagnosis of MVD.
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Doença do Vírus de Marburg , Marburgvirus , Animais , Anticorpos Monoclonais , Nucleoproteínas , Cromatografia de AfinidadeRESUMO
Oligodendrocytes (OCs) form myelin around axons, which is dependent on neuronal activity. This activity-dependent myelination plays a crucial role in training and learning. Previous studies have suggested that neuronal activity regulates proliferation and differentiation of oligodendrocyte precursor cells (OPCs) and myelination. In addition, deficient activity-dependent myelination results in impaired motor learning. However, the functional response of OC responsible for neuronal activity and their pathological changes is not fully elucidated. In this research, we aimed to understand the activity-dependent OC responses and their different properties by observing OCs using in vivo two-photon microscopy. We clarified that the Ca2+ activity in OCs is neuronal activity dependent and differentially regulated by neurotransmitters such as glutamate or adenosine triphosphate (ATP). Furthermore, in 5-month-old mice models of Alzheimer's disease, a period before the appearance of behavioral abnormalities, the elevated Ca2+ responses in OCs are ATP dependent, suggesting that OCs receive ATP from damaged tissue. We anticipate that our research will help in determining the correct therapeutic strategy for neurodegenerative diseases beyond the synapse.
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OBJECTIVE: A pathological excitatory action of the major inhibitory neurotransmitter γ-aminobutyric acid (GABA) has been observed in epilepsy. Blocking the Cl- importer NKCC1 with bumetanide is expected to reduce the neuronal intracellular Cl- concentration ([Cl- ]i ) and thereby attenuate the excitatory GABA response. Accordingly, several clinical trials of bumetanide for epilepsy were conducted. Although NKCC1 is expressed in both neurons and glial cells, an involvement of glial NKCC1 in seizures has not yet been reported. Astrocytes maintain high [Cl- ]i with NKCC1, and this gradient promotes Cl- efflux via the astrocytic GABAA receptor (GABAA R). This Cl- efflux buffers the synaptic cleft Cl- concentration to maintain the postsynaptic Cl- gradient during intense firing of GABAergic neurons, thereby sustaining its inhibitory action during seizure. In this study, we investigated the function of astrocytic NKCC1 in modulating the postsynaptic action of GABA in acute seizure models. METHODS: We used the astrocyte-specific conditional NKCC1 knockout (AstroNKCC1KO) mice. The seizurelike events (SLEs) in CA1 pyramidal neurons were triggered by tetanic stimulation of stratum radiatum in acute hippocampus slices. The SLE underlying GABAA R-mediated depolarization was evaluated by applying the GABAA R antagonist bicuculline. The pilocarpine-induced seizure in vivo was monitored in adult mice by the Racine scale. The SLE duration and tetanus stimulation intensity threshold and seizure behavior in AstroNKCC1KO mice and wild-type (WT) mice were compared. RESULTS: The AstroNKCC1KO mice were prone to seizures with lower threshold and longer duration of SLEs and larger GABAA R-mediated depolarization underlying the SLEs, accompanied by higher Racine-scored seizures. Bumetanide reduced these indicators of seizure in AstroNKCC1KO mice (which still express neuronal NKCC1), but not in the WT, both in vitro and in vivo. SIGNIFICANCE: Astrocytic NKCC1 inhibits GABA-mediated excitatory action during seizures, whereas neuronal NKCC1 has the converse effect, suggesting opposing actions of bumetanide on these cells.
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Bumetanida , Epilepsia , Membro 2 da Família 12 de Carreador de Soluto , Animais , Camundongos , Astrócitos , Bumetanida/farmacologia , Bumetanida/uso terapêutico , Epilepsia/tratamento farmacológico , Ácido gama-Aminobutírico/metabolismo , Neurônios , Receptores de GABA-A/fisiologia , Convulsões , Inibidores de Simportadores de Cloreto de Sódio e Potássio/farmacologia , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêutico , Membro 2 da Família 12 de Carreador de Soluto/genética , Sinapses , Cloretos/metabolismoRESUMO
Microglia are the only immune cells in the central nervous system. It has been shown that microglia actively regulate the number of neurons by participating in the cell death of neural stem cells during development and maturation. In addition, recent optical techniques have enabled in vivo imaging, which has revealed the function of microglia on synapses. Microglia regularly monitor synaptic activity and remove synapses that show abnormal activity in the event of brain infarction or other disorders. During development, microglia contribute to the formation of immature synapses by contacting dendrites during early synapse formation, and they are also involved in the de-synaptic process by selectively removing weakly active synapses through the use of classical complement cascade signaling. Furthermore, these abnormalities are known to contribute to the development of autism during development and to the development of Alzheimer's disease during maturation. In addition to this, microglia also contribute to plastic changes in synapses during the learning process in maturation. Furthermore, by modifying synaptic activity, microglia are known to be involved in changes in the activity of neuronal circuits. In addition to these synaptic functions, microglia are also known to be involved in the permeability of the blood-brain barrier. In this chapter, these functions will be summarized and discussed.
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Doença de Alzheimer , Fenômenos Fisiológicos do Sistema Nervoso , Humanos , Microglia , Sistema Nervoso Central , Barreira HematoencefálicaRESUMO
Brain function relies on both rapid electrical communication in neural circuitry and appropriate patterns or synchrony of neural activity. Rapid communication between neurons is facilitated by wrapping nerve axons with insulation by a myelin sheath composed largely of different lipids. Recent evidence has indicated that the extent of myelination of nerve axons can adapt based on neural activity levels and this adaptive myelination is associated with improved learning of motor tasks, suggesting such plasticity may enhance effective learning. In this study, we examined whether another aspect of myelin plasticity-changes in myelin lipid synthesis and composition-may also be associated with motor learning. We combined a motor learning task in mice with in vivo two-photon imaging of neural activity in the primary motor cortex (M1) to distinguish early and late stages of learning and then probed levels of some key myelin lipids using mass spectrometry analysis. Sphingomyelin levels were elevated in the early stage of motor learning while galactosylceramide levels were elevated in the middle and late stages of motor learning, and these changes were correlated across individual mice with both learning performance and neural activity changes. Targeted inhibition of oligodendrocyte-specific galactosyltransferase expression, the enzyme that synthesizes myelin galactosylceramide, impaired motor learning. Our results suggest regulation of myelin lipid composition could be a novel facet of myelin adaptations associated with learning.
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Galactosilceramidas , Bainha de Mielina , Camundongos , Animais , Bainha de Mielina/metabolismo , Galactosilceramidas/metabolismo , Axônios/metabolismo , Neurônios/metabolismo , Oligodendroglia/fisiologiaRESUMO
BACKGROUND: There is a shortage of general practitioners in Japan. With the revision of educational guidelines, general practice (GP) education has improved. However, the amount of education on GP in medical schools remains inconsistent. This study examined the relationship between medical students' amount of GP-related education and their subsequent choice of GP majors. METHODS: A retrospective cohort study was conducted in a teaching hospital in Japan. Participants were residents in the hospital. The exposure comprised compulsory lectures and training time for community-based medicine in medical schools. The outcome included participants choosing GP majors after their initial 2-year junior residency. RESULTS: Fifty-one participants were included in the final analysis. Of these, 14 majored in GP and 37 in non-GP after their initial 2-year junior residency. Of the participants who took GP lectures for 18 hours or more, 11 chose GP majors, and 18 chose non-GP majors (risk ratio, 2.78; 95% confidence interval [CI], 0.88-8.79). Of the participants who underwent training for 12 days or more, 10 chose GP majors, and 16 chose non-GP majors (risk ratio, 2.40; 95% CI, 0.87-6.68). CONCLUSION: The results do not support the association between the amount of compulsory undergraduate education for community-based medicine and the subsequent increase in the number of residents choosing GP majors in Japan. Educators would do well to explore different approaches, such as improving the quality of education to increase the number of GP residents. Further research is needed to reach more definitive conclusions.
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PURPOSE: To investigate whether deep cervical lymph node (DCLN) ligation alters intracranial cerebrospinal fluid (CSF) tracer dynamics and outflow using a rat model with intrathecal dynamic contrast-enhanced (DCE) MRI. METHODS: Six bilateral DCLN-ligated and six sham-operated rats were subjected to DCE MRI with Gd-BTDO3A, and dynamic T1-weighted images were acquired. ROIs were collected from the CSF at the C1 level (CSF_C1), CSF between the olfactory bulbs (CSF_OB), CSF at the pituitary recess (CSF_PitR), and CSF at the pineal recess (CSF_PinR), upper nasal turbinate (UNT), olfactory bulbs, cerebrum, and the jugular region. Time-intensity curves were evaluated, and the maximum slope, peak timing, peak signal ratio, and elimination half-life for the four CSF ROIs and UNT were calculated and compared. RESULTS: Delayed tracer arrival in the rostral CSF space and the nasal cavity with tracer retention in the ventral CSF space were observed in the ligation group. The maximum slopes were smaller in the ligation group at UNT (sham: 0.075 ± 0.0061, ligation: 0.044 ± 0.0086/min, P = 0.011). A significant difference was not detected in peak timings. The peak signal ratio values were lower in the ligation group at UNT (sham: 2.12 ± 0.19, ligation: 1.72 ± 0.11, P = 0.011). The elimination half-life was delayed in the ligation group at CSF_C1 (sham: 30.5 ± 2.70, ligation: 44.4 ± 12.6 min, P = 0.043), CSF_OB (sham: 30.2 ± 2.67, ligation: 44.8 ± 7.47 min, P = 0.021), and CSF_PitR (sham: 30.2 ± 2.49, ligation: 41.3 ± 7.57 min, P = 0.021). CONCLUSION: The DCLN ligation in rats blocked CSF outflow into the nasal cavity and caused CSF retention.
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The cholinergic efferent network from the medial septal nucleus to the hippocampus is crucial for learning and memory. This study aimed to clarify whether hippocampal cholinergic neurostimulating peptide (HCNP) has a rescue function in the cholinergic dysfunction of HCNP precursor protein (HCNP-pp) conditional knockout (cKO). Chemically synthesized HCNP or a vehicle were continuously administered into the cerebral ventricle of HCNP-pp cKO mice and littermate floxed (control) mice for two weeks via osmotic pumps. We immunohistochemically measured the cholinergic axon volume in the stratum oriens and functionally evaluated the local field potential in the CA1. Furthermore, choline acetyltransferase (ChAT) and nerve growth factor (NGF) receptor (TrkA and p75NTR) abundances were quantified in wild-type (WT) mice administered HCNP or the vehicle. As a result, HCNP administration morphologically increased the cholinergic axonal volume and electrophysiological theta power in HCNP-pp cKO and control mice. Following the administration of HCNP to WT mice, TrkA and p75NTR levels also decreased significantly. These data suggest that extrinsic HCNP may compensate for the reduced cholinergic axonal volume and theta power in HCNP-pp cKO mice. HCNP may function complementarily to NGF in the cholinergic network in vivo. HCNP may represent a therapeutic candidate for neurological diseases with cholinergic dysfunction, e.g., Alzheimer's disease and Lewy body dementia.
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Fator de Crescimento Neural , Neuropeptídeos , Camundongos , Animais , Fator de Crescimento Neural/metabolismo , Neuropeptídeos/metabolismo , Hipocampo/metabolismo , Colinérgicos/metabolismo , Colina O-Acetiltransferase/genética , Colina O-Acetiltransferase/metabolismoRESUMO
Cross-modal plasticity is the repurposing of brain regions associated with deprived sensory inputs to improve the capacity of other sensory modalities. The functional mechanisms of cross-modal plasticity can indicate how the brain recovers from various forms of injury and how different sensory modalities are integrated. Here, we demonstrate that rewiring of the microglia-mediated local circuit synapse is crucial for cross-modal plasticity induced by visual deprivation (monocular deprivation [MD]). MD relieves the usual inhibition of functional connectivity between the somatosensory cortex and secondary lateral visual cortex (V2L). This results in enhanced excitatory responses in V2L neurons during whisker stimulation and a greater capacity for vibrissae sensory discrimination. The enhanced cross-modal response is mediated by selective removal of inhibitory synapse terminals on pyramidal neurons by the microglia in the V2L via matrix metalloproteinase 9 signaling. Our results provide insights into how cortical circuits integrate different inputs to functionally compensate for neuronal damage.