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2.
Acute Med Surg ; 11(1): e954, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38655507

RESUMEN

Background: Factor Xa inhibitors are direct oral anticoagulants that are extremely useful in clinical applications, safe, and do not require dose adjustment. It is desirable to be able to monitor their effects in the event of hemorrhagic complications requiring neutralization. However, it is difficult to monitor their activity and neutralization using conventional coagulation tests. Case Presentation: We report three patients taking factor Xa inhibitors who underwent rotational thromboelastography (ROTEM) monitoring before and after neutralization with andexanet alfa. All three patients had hemorrhagic complications that required neutralization of their factor Xa inhibitors using andexanet alfa. One ROTEM parameter, the EXTEM clotting time (EXTEM-CT), was immediately shortened after andexanet alfa bolus administration, without subsequent extension of the EXTEM-CT assessed 4 h after the bolus dose. Conclusion: ROTEM parameters, particularly EXTEM-CT, might be useful for monitoring neutralization of factor Xa inhibitors.

3.
EMBO Rep ; 25(3): 1176-1207, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38316902

RESUMEN

For mucociliary clearance of pathogens, tracheal multiciliated epithelial cells (MCCs) organize coordinated beating of cilia, which originate from basal bodies (BBs) with basal feet (BFs) on one side. To clarify the self-organizing mechanism of coordinated intracellular BB-arrays composed of a well-ordered BB-alignment and unidirectional BB-orientation, determined by the direction of BB to BF, we generated double transgenic mice with GFP-centrin2-labeled BBs and mRuby3-Cep128-labeled BFs for long-term, high-resolution, dual-color live-cell imaging in primary-cultured tracheal MCCs. At early timepoints of MCC differentiation, BB-orientation and BB-local alignment antecedently coordinated in an apical microtubule-dependent manner. Later during MCC differentiation, fluctuations in BB-orientation were restricted, and locally aligned BB-arrays were further coordinated to align across the entire cell (BB-global alignment), mainly in an apical intermediate-sized filament-lattice-dependent manner. Thus, the high coordination of the BB-array was established for efficient mucociliary clearance as the primary defense against pathogen infection, identifying apical cytoskeletons as potential therapeutic targets.


Asunto(s)
Cuerpos Basales , Citoesqueleto , Ratones , Animales , Microtúbulos , Cilios , Células Epiteliales
4.
STAR Protoc ; 5(1): 102844, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38277267

RESUMEN

cIPAD is a fluorescent indicator that allows the visualization of trans-interactions of clustered protocadherin (Pcdh), a cell adhesion molecule that mediates neuronal self-recognition. We describe steps for using HEK293T cells to visualize Pcdh trans-interactions across cells as a preliminary experiment before using dissociated mouse neurons. We then detail procedures for visualizing Pcdh trans-interactions between processes originating from the same neurons, which are considered as Pcdh-mediated neuronal self-recognition. For complete details on the use and execution of this protocol, please refer to Kanadome et al.1.


Asunto(s)
Cadherinas , Protocadherinas , Humanos , Animales , Ratones , Cadherinas/genética , Cadherinas/metabolismo , Células HEK293 , Neuronas/metabolismo , Adhesión Celular
5.
bioRxiv ; 2023 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-37790358

RESUMEN

By the use of a novel experimental system, the step-wheel, we investigated the neural underpinnings of complex and continuous movements. We recorded neural activities from the dorsolateral striatum and found neurons sensitive to movement rhythm parameters. These neurons responded to specific combinations of interval, phase, and repetition of movement, effectively forming what we term "rhythm receptive fields." Some neurons even responsive to the combination of movement phases of multiple body parts. In parallel, cortical recordings in sensorimotor areas highlighted a paucity of neurons responsive to multiple parameter combinations, relative to those in the striatum. These findings have implications for comprehending motor coordination deficits seen in brain disorders including Parkinson's disease. Movement encoding by rhythm receptive fields should streamline the brain's capacity to encode temporal patterns, help to resolve the degrees of freedom problem. Such rhythm fields hint at the neural mechanisms governing effective motor control and processing of rhythmic information.

6.
eNeuro ; 10(10)2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37890993

RESUMEN

Functional neural circuits in the cerebral cortex are established through specific neural connections between excitatory and various inhibitory cell types. However, the molecular mechanisms underlying synaptic partner recognition remain unclear. In this study, we examined the impact of clustered protocadherin-γ (cPcdhγ) gene deletion in parvalbumin-positive (PV+) cells on intralaminar and translaminar neural circuits formed between PV+ and pyramidal (Pyr) cells in the primary visual cortex (V1) of male and female mice. First, we used whole-cell recordings and laser-scan photostimulation with caged glutamate to map excitatory inputs from layer 2/3 to layer 6. We found that cPcdhγ-deficient PV+ cells in layer 2/3 received normal translaminar inputs from Pyr cells through layers 2/3-6. Second, to further elucidate the effect on PV+-Pyr microcircuits within intralaminar layer 2/3, we conducted multiple whole-cell recordings. While the overall connection probability of PV+-Pyr cells remained largely unchanged, the connectivity of PV+-Pyr was significantly different between control and PV+-specific cPcdhγ-conditional knock-out (PV-cKO) mice. In control mice, the number of reciprocally connected PV+ cells was significantly higher than PV+ cells connected one way to Pyr cells, a difference that was not significant in PV-cKO mice. Interestingly, the proportion of highly reciprocally connected PV+ cells to Pyr cells with large unitary IPSC (uIPSC) amplitudes was reduced in PV-cKO mice. Conversely, the proportion of middle reciprocally connected PV+ cells to Pyr cells with large uIPSC amplitudes increased compared with control mice. This study demonstrated that cPcdhγ in PV+ cells modulates their reciprocity with Pyr cells in the cortex.


Asunto(s)
Parvalbúminas , Protocadherinas , Ratones , Femenino , Masculino , Animales , Parvalbúminas/metabolismo , Potenciales Postsinápticos Inhibidores , Células Piramidales/fisiología , Corteza Cerebral/metabolismo , Interneuronas/metabolismo
7.
Acute Med Surg ; 10(1): e897, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37841965

RESUMEN

Aim: To determine whether the rewarming rate is associated with neurological outcomes in patients with post-cardiac arrest syndrome treated with targeted temperature management (TTM) at 34°C. Methods: We conducted a retrospective analysis of a nationwide cohort study of out-of-hospital cardiac arrest in Japan. Adult patients who experienced a return of spontaneous circulation and completed TTM at 34°C between June 2014 and December 2019 were divided equally into three groups (slow, moderate, and rapid) according to their rewarming rates from 34°C to 36°C. The rates of favorable neurological outcomes (Cerebral Performance Category of 1-2 after 30 days) were compared among the groups, and the adjusted odds ratios for a favorable neurological outcome were calculated for the groups. Results: We analyzed 348, 357, and 358 patients in the slow, moderate, and rapid groups, respectively. The periods of rewarming from 34°C to 36°C were 41.9 ± 10.5, 22.4 ± 1.8, and 12.2 ± 3.6 h, respectively. The number of favorable neurological outcomes after 30 days was 121 (34.8%), 125 (35.0%), and 147 (41.1%), respectively, with no significant differences among the three groups (p = 0.145). Rapid rewarming was independently associated with a favorable neurological outcome compared with slow rewarming (adjusted odds ratio 1.57 [95% confidence interval 1.04-2.37]; p = 0.031). Conclusions: Rapid rewarming after TTM at 34°C was associated with a more favorable neurological outcome than slow rewarming.

8.
Acute Med Surg ; 10(1): e892, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37753227

RESUMEN

Aim: To determine whether dispatcher-provided cardiopulmonary resuscitation (CPR) instructions improve the outcomes of out-of-hospital cardiac arrest (OHCA). Methods: Cases registered in the Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest (JAAM-OHCA) Registry between June 2014 and December 2019 were included. Cases in which the dispatcher provided CPR instructions to the bystander were included in the "Instructions" group", and cases without CPR instructions were included in the "No Instructions" group. The primary outcome was the proportion of patients with a favorable neurological outcome, defined as a Glasgow-Pittsburgh cerebral performance category scale of 1 to 2 at 1 month after OHCA. Results: Overall, 51,199 patients with OHCA were registered in the JAAM-OHCA Registry during the study period. Of these, 33,745 were eligible for the study, with 16,509 in the Instructions group and 17,236 in the No Instructions group. The proportion of patients with a favorable neurological outcome at 1 month after OHCA was inferior in the Instructions group than in the No Instructions group (2.3% versus 3.0%, p < 0.001). After adjustment for patient background characteristics, no association was found between CPR instructions provided by a dispatcher and favorable neurological outcomes at 1 month after OHCA (adjusted odds ratio, 1.000; 95% confidence interval, 0.869-1.151, p = 0.996). Conclusion: The present study found no clear clinical benefit of dispatcher-provided CPR instructions on the neurological outcomes of cases with OHCA.

9.
Proc Natl Acad Sci U S A ; 120(38): e2301003120, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37695902

RESUMEN

Clustered protocadherin (Pcdh) functions as a cell recognition molecule through the homophilic interaction in the central nervous system. However, its interactions have not yet been visualized in neurons. We previously reported PcdhγB2-Förster resonance energy transfer (FRET) probes to be applicable only to cell lines. Herein, we designed γB2-FRET probes by fusing FRET donor and acceptor fluorescent proteins to a single γB2 molecule and succeeded in visualizing γB2 homophilic interaction in cultured hippocampal neurons. The γB2-FRET probe localized in the soma and neurites, and FRET signals, which were observed at contact sites between neurites, eliminated by ethylene glycol tetraacetic acid (EGTA) addition. Live imaging revealed that the FRET-negative γB2 signals rapidly moved along neurites and soma, whereas the FRET-positive signals remained in place. We observed that the γB2 proteins at synapses rarely interact homophilically. The γB2-FRET probe might allow us to elucidate the function of the homophilic interaction and the cell recognition mechanism.


Asunto(s)
Neuronas , Protocadherinas , Neuritas , Cuerpo Celular , Comunicación Celular
10.
iScience ; 26(7): 107238, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37534169

RESUMEN

Clustered protocadherin (Pcdh), a cell adhesion protein, is involved in the self-recognition and non-self-discrimination of neurons by conferring diversity on the cell surface. Although the roles of Pcdh in neurons have been elucidated, it has been challenging to visualize its adhesion activity in neurons, which is a molecular function of Pcdh. Here, we present fluorescent indicators, named IPADs, which visualize the interaction of protocadherin-α4 isoform (α4). IPADs successfully visualize not only homophilic α4 trans-interactions, but also combinatorial homophilic interactions between cells. The reversible nature of IPADs overcomes a drawback of the split-GFP technique and allows for monitoring the dissociation of α4 trans-interactions. Specially designed IPADs for self-recognition are able to monitor the formation and disruption of α4 trans-interactions between processes originating from the same neurons. We expect that IPADs will be useful tools for obtaining spatiotemporal information on Pcdh interactions in neuronal self-recognition and non-self-discrimination processes.

11.
iScience ; 26(5): 106765, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37216111

RESUMEN

Motor chunking is important for motor execution, allowing atomization and efficiency of movement sequences. However, it remains unclear why and how chunks contribute to motor execution. To analyze the structure of naturally occurring chunks, we trained mice to run in a complex series of steps and identified the formation of chunks. We found that intervals (cycle) and the positional relationship between the left and right limbs (phase) of steps inside the chunks, unlike those outside the chunks, were consistent across occurrences. Further, licking by the mice was also more periodic and linked to the specific phases of limb movements within the chunk. Based on these findings, we propose the rhythm chunking hypothesis, whereby within chunks, the repetitive movements of many body parts are linked by the rhythm parameters: cycle and phase. The computational complexity of movement may thereby be reduced by adjusting movements as the combination of rhythms.

13.
Cell Rep ; 42(5): 112383, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37086724

RESUMEN

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.


Asunto(s)
Microglía , Corteza Visual , Animales , Neuronas/fisiología , Sinapsis/fisiología , Células Piramidales , Corteza Visual/fisiología , Plasticidad Neuronal/fisiología , Vibrisas/fisiología , Corteza Somatosensorial/fisiología
14.
Ann N Y Acad Sci ; 1523(1): 51-61, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37002535

RESUMEN

Hair follicles (HFs) undergo cyclic phases of growth, regression, and rest in association with hair shafts to maintain the hair coat. Nonsense mutations in the tight junction protein claudin (CLDN)-1 cause hair loss in humans. Therefore, we evaluated the roles of CLDNs in hair retention. Among the 27 CLDN family members, CLDN1, CLDN3, CLDN4, CLDN6, and CLDN7 were expressed in the inner bulge layer, isthmus, and sebaceous gland of murine HFs. Hair phenotypes were observed in Cldn1 weaker knockdown and Cldn3-knockout (Cldn1Δ/Δ Cldn3-/- ) mice. Although hair growth was normal, Cldn1Δ/Δ Cldn3-/- mice showed striking hair loss in the first telogen. Simultaneous deficiencies in CLDN1 and CLDN3 caused abnormalities in telogen HFs, such as an aberrantly layered architecture of epithelial cell sheets in bulges with multiple cell layers, mislocalization of bulges adjacent to sebaceous glands, and dilated hair canals. Along with the telogen HF abnormalities, which shortened the hair retention period, there was an enhanced proliferation of the epithelium surrounding HFs in Cldn1Δ/Δ Cldn3-/- mice, causing accelerated hair regrowth in adults. Our findings suggested that CLDN1 and CLDN3 may regulate hair retention in infant mice by maintaining the appropriate layered architecture of HFs, a deficiency of which can lead to alopecia.


Asunto(s)
Alopecia , Animales , Ratones , Alopecia/genética , Claudina-1/genética , Claudina-1/metabolismo , Claudina-3/genética , Claudina-3/metabolismo , Claudina-4/metabolismo , Mutación , Envejecimiento
15.
Intern Med ; 62(5): 717-722, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36543214

RESUMEN

Objectives Coronavirus disease 2019 (COVID-19) reportedly causes thromboembolic complications due to coagulopathy with hypercoagulability and a hypofibrinolytic state. We evaluated the time-course of coagulopathy in patients with severe COVID-19 from admission to discharge from our intensive-care unit (ICU). Methods We conducted a retrospective study of adults with severe COVID-19 admitted to our ICU between January 20, 2021, and March 31, 2022. We obtained clinical information, laboratory data, and rotational thromboelastometry (ROTEM) parameters at admission and discharge. Results Fifteen patients were included. Fibrinogen and D-dimer values did not change significantly but were above the normal ranges at admission and discharge. Regarding ROTEM parameters, the maximum clot firmness in fibrinogen function (FIBTEM), a marker of hypercoagulability, did not change significantly but was above the normal range at admission and discharge [median (interquartile range), admission vs. discharge: 31 (25-34) mm vs. 31 (27-32) mm, p=0.589]. The maximum lysis at 60 minutes in the extrinsic coagulation pathway (EXTEM) and intrinsic coagulation pathway (INTEM), as markers of the fibrinolytic function, were both significantly lower at discharge than at admission [median (interquartile range), admission vs. discharge: EXTEM, 3 (2-4) vs. 1 (0-2), p=0.011; INTEM, 3 (1-6) vs. 1 (0-2), p=0.008]. Conclusion This study revealed a persistent hypercoagulable state at ICU discharge and a worse hypofibrinolytic state at discharge than at admission. These results may contribute to a better understanding of coagulopathies in the acute to subacute phases of severe COVID-19.


Asunto(s)
Trastornos de la Coagulación Sanguínea , COVID-19 , Trombofilia , Adulto , Humanos , Tromboelastografía/métodos , Estudios Retrospectivos , Pruebas de Coagulación Sanguínea , Fibrinógeno
16.
iScience ; 26(1): 105766, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36582829

RESUMEN

Clustered protocadherin is a family of cell-surface recognition molecules implicated in neuronal connectivity that has a diverse isoform repertoire and homophilic binding specificity. Mice have 58 isoforms, encoded by Pcdhα, ß, and γ gene clusters, and mutant mice lacking all isoforms died after birth, displaying massive neuronal apoptosis and synapse loss. The current hypothesis is that the three specific γC-type isoforms, especially γC4, are essential for the phenotype, raising the question about the necessity of isoform diversity. We generated TC mutant mice that expressed the three γC-type isoforms but lacked all the other 55 isoforms. The TC mutants died immediately after birth, showing massive neuronal death, and γC3 or γC4 expression did not prevent apoptosis. Restoring the α- and ß-clusters with the three γC alleles rescued the phenotype, suggesting that along with the three γC-type isoforms, other isoforms are also required for the survival of neurons and individual mice.

17.
Tomography ; 8(6): 2806-2814, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36548526

RESUMEN

This study investigated the relationship between the severity of pneumonia based on chest CT findings and that of pancreatic steatosis assessed using an automated volumetric measurement of the CT fat volume fraction (CT-FVF) of the pancreas, using unenhanced three-dimensional CT in polymerase chain reaction (PCR)-confirmed COVID-19 patients. The study population consisted of 128 patients with PCR-confirmed COVID-19 infection who underwent CT examinations. The CT-FVF of the pancreas was calculated using a histogram analysis for the isolation of fat-containing voxels in the pancreas. The CT-FVF (%) of the pancreas had a significantly positive correlation with the lung severity score on CT (ρ = 0.549, p < 0.01). CT-FVF (%) of the pancreas in the severe pneumonia group was significantly higher than that of the non-severe pneumonia group (21.7% vs. 7.8%, p < 0.01). The area under the curve of CT-FVF (%) of the pancreas in predicting the severity of pneumonia on CT was calculated to be 0.82, with a sensitivity of 88% and a specificity of 68% at a threshold for the severity score of 12.3. The automated volumetric measurement of the CT-FVF of the pancreas using unenhanced CT can help estimate disease severity in patients with COVID-19 pneumonia based on chest CT findings.


Asunto(s)
COVID-19 , Neumonía , Humanos , COVID-19/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Páncreas/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico
18.
Acta Neuropathol Commun ; 10(1): 172, 2022 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-36447271

RESUMEN

CCCTC-binding factor (CTCF) has a key role in higher-order chromatin architecture that is important for establishing and maintaining cell identity by controlling gene expression. In the mature cerebellum, CTCF is highly expressed in Purkinje cells (PCs) as compared with other cerebellar neurons. The cerebellum plays an important role in motor function by regulating PCs, which are the sole output neurons, and defects in PCs cause motor dysfunction. However, the role of CTCF in PCs has not yet been explored. Here we found that the absence of CTCF in mouse PCs led to progressive motor dysfunction and abnormal dendritic morphology in those cells, which included dendritic self-avoidance defects and a proximal shift in the climbing fibre innervation territory on PC dendrites. Furthermore, we found the peculiar lamellar structures known as "giant lamellar bodies" (GLBs), which have been reported in PCs of patients with Werdnig-Hoffman disease, 13q deletion syndrome, and Krabbe disease. GLBs are localized to PC dendrites and are assumed to be associated with neurodegeneration. They have been noted, however, only in case reports following autopsy, and reports of their existence have been very limited. Here we show that GLBs were reproducibly formed in PC dendrites of a mouse model in which CTCF was deleted. GLBs were not noted in PC dendrites at infancy but instead developed over time. In conjunction with GLB development in PC dendrites, the endoplasmic reticulum was almost absent around the nuclei, the mitochondria were markedly swollen and their cristae had decreased drastically, and almost all PCs eventually disappeared as severe motor deficits manifested. Our results revealed the important role of CTCF during normal development and in maintaining PCs and provide new insights into the molecular mechanism of GLB formation during neurodegenerative disease.


Asunto(s)
Enfermedades Neurodegenerativas , Células de Purkinje , Animales , Ratones , Cuerpos Lamelares , Cerebelo , Dendritas
19.
Genome Res ; 32(5): 945-955, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35534232

RESUMEN

De novo mutations accumulate with zygotic cell divisions. However, the occurrence of these mutations and the way they are inherited by somatic cells and germ cells remain unclear. Here, we present a novel method to reconstruct cell lineages. We identified mosaic mutations in mice using deep whole-genome sequencing and reconstructed embryonic cell lineages based on the variant allele frequencies of the mutations. The reconstructed trees were confirmed using nuclear transfer experiments and the genotyping of approximately 50 offspring of each tree. The most detailed tree had 32 terminal nodes and showed cell divisions from the fertilized egg to germ cell- and somatic cell-specific lineages, indicating at least five independent cell lineages that would be selected as founders of the primordial germ cells. The contributions of each lineage to germ cells and offspring varied widely. At the emergence of the germ cell-specific lineages, 10-15 embryonic mutations had accumulated, suggesting that the pregastrulation mutation rate is 1.0 mutation per mitosis. Subsequent mutation rates were 0.7 for germ cells and 13.2 for tail fibroblasts. Our results show a new framework to assess embryonic lineages; further, we suggest an evolutionary strategy for preserving heterogeneity owing to postzygotic mutations in offspring.


Asunto(s)
Células Germinativas , Tasa de Mutación , Animales , Linaje de la Célula/genética , Ratones , Mutación , Cigoto
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