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1.
BMC Neurol ; 24(1): 119, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605286

RESUMO

BACKGROUND: Ischemic stroke in young adults can be caused by a variety of etiologies including the monogenic disorders. Visceral heterotaxy is a condition caused by abnormal left-right determinations during embryonic development. We aimed to determine the cause of a young ischemic stroke patient with visceral heterotaxy. CASE PRESENTATION: We performed neurological, radiological, and genetic evaluations in a 17-year-old male patient presenting ischemic stroke and visceral heterotaxy to determine the underlying cause of this rare disease combination. Brain magnetic resonance imaging (MRI) showed evidence of embolic stroke, abdominal computed tomography (CT) showed visceral heterotaxy, and echocardiogram showed cardiac anomaly with right-to-left-shunt (RLS). Whole genome sequencing (WGS) revealed a heterozygous missense variant (NM_018055.5: c.1016 T > C, p.(Met339Val)) in the NODAL gene, which is essential to the determination of the left-right body axis. CONCLUSIONS: Our study highlights the importance of evaluating genetic etiology in young ischemic stroke and the need for stroke risk management in visceral heterotaxy patients with RLS. To the best of our knowledge, we report the first genetically-confirmed case of visceral heterotaxy with young embolic stroke reported to date.


Assuntos
Anormalidades Cardiovasculares , AVC Embólico , Síndrome de Heterotaxia , Acidente Vascular Cerebral , Masculino , Feminino , Gravidez , Adulto Jovem , Humanos , Adolescente , Síndrome de Heterotaxia/genética , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/genética , Imageamento por Ressonância Magnética
2.
J Physiol Sci ; 74(1): 23, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561668

RESUMO

Cardiac glycosides, known as inhibitors of Na+,K+-ATPase, have anti-cancer effects such as suppression of cancer cell proliferation and induction of cancer cell death. Here, we examined the signaling pathway elicited by cardiac glycosides in the human hepatocellular carcinoma HepG2 cells and human epidermoid carcinoma KB cells. Three kinds of cardiac glycosides (ouabain, oleandrin, and digoxin) inhibited the cancer cell proliferation and decreased the expression level of thyroid adenoma-associated protein (THADA). Interestingly, the knockdown of THADA inhibited cancer cell proliferation, and the proliferation was significantly rescued by re-expression of THADA in the THADA-knockdown cells. In addition, the THADA-knockdown markedly decreased the expression level of L-type amino acid transporter LAT1. Cardiac glycosides also reduced the LAT1 expression. The LAT1 inhibitor, JPH203, significantly weakened the cancer cell proliferation. These results suggest that the binding of cardiac glycosides to Na+,K+-ATPase negatively regulates the THADA-LAT1 pathway, exerting the anti-proliferative effect in cancer cells.


Assuntos
Glicosídeos Cardíacos , Neoplasias da Glândula Tireoide , Humanos , Glicosídeos Cardíacos/farmacologia , Glicosídeos Cardíacos/metabolismo , Glicosídeos/farmacologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Ouabaína/farmacologia , Proteínas de Neoplasias/metabolismo
3.
World J Gastroenterol ; 30(10): 1368-1376, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38596494

RESUMO

BACKGROUND: Colorectal cancer (CRC) is a global health concern, with advanced-stage diagnoses contributing to poor prognoses. The efficacy of CRC screening has been well-established; nevertheless, a significant proportion of patients remain unscreened, with > 70% of cases diagnosed outside screening. Although identifying specific subgroups for whom CRC screening should be particularly recommended is crucial owing to limited resources, the association between the diagnostic routes and identification of these subgroups has been less appreciated. In the Japanese cancer registry, the diagnostic routes for groups discovered outside of screening are primarily categorized into those with comorbidities found during hospital visits and those with CRC-related symptoms. AIM: To clarify the stage at CRC diagnosis based on diagnostic routes. METHODS: We conducted a retrospective observational study using a cancer registry of patients with CRC between January 2016 and December 2019 at two hospitals. The diagnostic routes were primarily classified into three groups: Cancer screening, follow-up, and symptomatic. The early-stage was defined as Stages 0 or I. Multivariate and univariate logistic regressions were exploited to determine the odds of early-stage diagnosis in the symptomatic and cancer screening groups, referencing the follow-up group. The adjusted covariates were age, sex, and tumor location. RESULTS: Of the 2083 patients, 715 (34.4%), 1064 (51.1%), and 304 (14.6%) belonged to the follow-up, symptomatic, and cancer screening groups, respectively. Among the 2083 patients, CRCs diagnosed at an early stage were 57.3% (410 of 715), 23.9% (254 of 1064), and 59.5% (181 of 304) in the follow-up, symptomatic, and cancer screening groups, respectively. The symptomatic group exhibited a lower likelihood of early-stage diagnosis than the follow-up group [P < 0.001, adjusted odds ratio (aOR), 0.23; 95% confidence interval (95%CI): 0.19-0.29]. The likelihood of diagnosis at an early stage was similar between the follow-up and cancer screening groups (P = 0.493, aOR for early-stage diagnosis in the cancer screening group vs follow-up group = 1.11; 95%CI = 0.82-1.49). CONCLUSION: CRCs detected during hospital visits for comorbidities were diagnosed earlier, similar to cancer screening. CRC screening should be recommended, particularly for patients without periodical hospital visits for comorbidities.


Assuntos
Colonoscopia , Neoplasias Colorretais , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Estudos Retrospectivos , Modelos Logísticos , Detecção Precoce de Câncer
4.
Intern Med ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38403773

RESUMO

Post-transplant lymphoproliferative disorders (PTLDs) are lymphoproliferative diseases that occur after solid organ transplantation or hematopoietic stem cell transplantation (HSCT). The development of PTLD is often associated with reactivation of Epstein-Barr virus (EBV). A 26-year-old woman with a history of HSCT and total-body irradiation developed spinal cord hemorrhage from a radiation-induced cavernous hemangioma (RICH) shortly after the development of classical Hodgkin lymphoma PTLD with EBV reactivation. Although little is known about the factors leading to hemorrhagic events from spinal cord RICH, we suspect that EBV reactivation may have been a factor contributing to the hemorrhage in the present case.

5.
J Mol Diagn ; 26(2): 85-95, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38008286

RESUMO

Hereditary repeat diseases are caused by an abnormal expansion of short tandem repeats in the genome. Among them, spinocerebellar ataxia (SCA) is a heterogeneous disease, and currently, 16 responsible repeats are known. Genetic diagnosis is obtained by analyzing the number of repeats through separate testing of each repeat. Although simultaneous detection of candidate repeats using current massively parallel sequencing technologies has been developed to avoid complicated multiple experiments, these methods are generally expensive. This study developed a cost-effective SCA repeat panel [Flongle SCA repeat panel sequencing (FLO-SCAp)] using Cas9-mediated targeted long-read sequencing and the smallest long-read sequencing apparatus, Flongle. This panel enabled the detection of repeat copy number changes, internal repeat sequences, and DNA methylation in seven patients with different repeat expansion diseases. The median (interquartile range) values of coverage and on-target rate were 39.5 (12 to 72) and 11.6% (7.5% to 16.5%), respectively. This approach was validated by comparing repeat copy number changes measured by FLO-SCAp and short-read whole-genome sequencing. A high correlation was observed between FLO-SCAp and short-read whole-genome sequencing when the repeat length was ≤250 bp (r = 0.98; P < 0.001). Thus, FLO-SCAp represents the most cost-effective method for conducting multiplex testing of repeats and can serve as the first-line diagnostic tool for SCA.


Assuntos
Sistemas CRISPR-Cas , Ataxias Espinocerebelares , Humanos , Análise Custo-Benefício , Ataxias Espinocerebelares/diagnóstico , Ataxias Espinocerebelares/genética , Repetições de Microssatélites/genética , Sequenciamento Completo do Genoma , Sequenciamento de Nucleotídeos em Larga Escala
6.
Clin Neurophysiol ; 158: 1-15, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38113692

RESUMO

OBJECTIVE: The aim of this study was to clarify the roles of the cerebellum and basal ganglia for temporal integration. METHODS: We studied 39 patients with spinocerebellar degeneration (SCD), comprising spinocerebellar atrophy 6 (SCA6), SCA31, Machado-Joseph disease (MJD, also called SCA3), and multiple system atrophy (MSA). Thirteen normal subjects participated as controls. Participants were instructed to tap on a button in synchrony with isochronous tones. We analyzed the inter-tap interval (ITI), synchronizing tapping error (STE), negative asynchrony, and proportion of delayed tapping as indicators of tapping performance. RESULTS: The ITI coefficient of variation was increased only in MSA patients. The standard variation of STE was larger in SCD patients than in normal subjects, especially for MSA. Negative asynchrony, which is a tendency to tap the button before the tones, was prominent in SCA6 and MSA patients, with possible basal ganglia involvement. SCA31 patients exhibited normal to supranormal performance in terms of the variability of STE, which was surprising. CONCLUSIONS: Cerebellar patients generally showed greater STE variability, except for SCA31. The pace of tapping was affected in patients with possible basal ganglia pathology. SIGNIFICANCE: Our results suggest that interaction between the cerebellum and the basal ganglia is essential for temporal processing. The cerebellum and basal ganglia and their interaction regulate synchronized tapping, resulting in distinct tapping pattern abnormalities among different SCD subtypes.


Assuntos
Atrofia de Múltiplos Sistemas , Ataxias Espinocerebelares , Degenerações Espinocerebelares , Humanos , Cerebelo , Ataxias Espinocerebelares/patologia , Gânglios da Base/patologia
7.
Nihon Yakurigaku Zasshi ; 158(6): 465-468, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-37914325

RESUMO

Na+,K+-ATPases are essential for maintaining the membrane potential in almost all cells, and their catalytic subunits have four isoforms (α1-α4). Volume-regulated anion channel (VRAC) plays an important role in the cell death signaling pathway in addition to its fundamental role in cell volume maintenance. First, we introduce that disruption of actin filaments cause the dysfunction of VRAC, which elicits resistance to cisplatin in the cancer cells. Next, we summarize the cardiac glycosides-induced signaling pathway mediated by the crosstalk between Na+,K+-ATPase α1-isoform (α1NaK) and VRAC in the membrane microdomain of the cancer cells. In this mechanism, sub-micromolar concentrations of cardiac glycosides bind to the receptor-type α1NaK, and generate VRAC activities concomitantly with a deceleration of cancer cell proliferation. Finally, we summarize the pathophysiological function of α3NaK, which is abnormally expressed in the intracellular vesicles of cancer cells. The cancer cell can survive even under loss of anchorage because they have the avoidance mechanism for anoikis. On cancer cell detachment, we found that intracellular α3NaK is translocated to the plasma membrane and this event contributes to the survival of the cells. Interestingly, cardiac glycosides inhibited the α3NaK translocation and cell survival. Our findings may open up new opportunities for the development of cancer medicines.


Assuntos
Glicosídeos Cardíacos , Neoplasias , Humanos , ATPase Trocadora de Sódio-Potássio/metabolismo , Glicosídeos Cardíacos/farmacologia , Membrana Celular , Íons/metabolismo , Transdução de Sinais , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
9.
Nat Commun ; 14(1): 6499, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37838794

RESUMO

Previous work has shown that motor skill learning stimulates and requires generation of myelinating oligodendrocytes (OLs) from their precursor cells (OLPs) in the brains of adult mice. In the present study we ask whether OL production is also required for non-motor learning and cognition, using T-maze and radial-arm-maze tasks that tax spatial working memory. We find that maze training stimulates OLP proliferation and OL production in the medial prefrontal cortex (mPFC), anterior corpus callosum (genu), dorsal thalamus and hippocampal formation of adult male mice; myelin sheath formation is also stimulated in the genu. Genetic blockade of OL differentiation and neo-myelination in Myrf conditional-knockout mice strongly impairs training-induced improvements in maze performance. We find a strong positive correlation between the performance of individual wild type mice and the scale of OLP proliferation and OL generation during training, but not with the number or intensity of c-Fos+ neurons in their mPFC, underscoring the important role played by OL lineage cells in cognitive processing.


Assuntos
Treino Cognitivo , Memória de Curto Prazo , Humanos , Camundongos , Animais , Masculino , Oligodendroglia , Camundongos Knockout , Cognição , Bainha de Mielina/fisiologia
10.
J Stroke Cerebrovasc Dis ; 32(11): 107344, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37722223

RESUMO

BACKGROUND: High-risk patent foramen ovale (PFO) could be pathological in cryptogenic stroke (CS), but its clinical characteristics have not been fully studied, especially in elderly patients. METHODS: Patients with CS were enrolled in the CHALLENGE ESUS/CS registry, a multicenter registry of CS patients undergoing transesophageal echocardiography. Clinical characteristics were compared among three groups: high-risk PFO group, large shunt PFO (≥25 microbubbles) or PFO with atrial septal aneurysm (ASA); right-to-left shunt (RLS) group, RLS including PFO with <25 microbubbles or without ASA; and no-RLS group. RESULTS: In total, 654 patients were analyzed: 91, 221, and 342 in the high-risk PFO, RLS, and no-RLS groups, respectively. In multinomial logistic regression analysis, the male sex (odds ratio [OR] 1.825 [1.067-3.122]) was independently associated with high-risk PFO, but hypertension (OR, 0.562 [0.327-0.967]), multiple infarctions (OR, 0.601 [0.435-0.830]), and other cardioaortic embologenic risks (OR, 0.514 [0.294-0.897]) were inversely associated with high-risk PFO compared with non-RLS. In 517 patients aged ≥60 years, multiple infarctions (OR, 0.549 [0.382-0.788]) and other cardioaortic embologenic risks (OR, 0.523 [0.286-0.959]) were inversely associated with high-risk PFO. CONCLUSIONS: High-risk PFO had specific clinical characteristics and possible mechanistic associations, and this trend was consistent among CS patients aged ≥60 years. CLINICAL TRIAL REGISTRATION INFORMATION: http://www.umin.ac.jp/ctr/ (UMIN000032957).

11.
Clin Neurophysiol ; 155: 99-106, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37596134

RESUMO

OBJECTIVE: To elucidate long-term potentiation (LTP)-like effects on the primary motor cortical (M1) in progressive supranuclear palsy (PSP) and its relationships with clinical features. METHODS: Participants were 18 probable/possible PSP Richardson syndrome (PSP-RS) patients and 17 healthy controls (HC). We used quadripulse stimulation (QPS) over the M1 with an interstimulus interval of 5 ms (QPS-5) to induce LTP-like effect and analyzed the correlations between the degree of LTP-like effect and clinical features. We also evaluated cortical excitability using short interval intracortical inhibition (SICI), intracortical facilitation (ICF) and short interval intracortical facilitation (SICF) in 15 PSP patients and 17 HC. RESULTS: LTP-like effect after QPS in PSP was smaller than HC and negatively correlated with Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) score, especially bradykinesia, but not with either age or any scores of cognitive functions. The SICI was abnormally reduced in PSP, but neither ICF nor SICF differed from those of normal subjects. None of these cortical excitability parameters correlated with any clinical features. CONCLUSIONS: LTP induction was impaired in PSP. The degree of LTP could reflect the severity of bradykinesia. The bradykinesia may partly relate with the motor cortical dysfunction. SIGNIFICANCE: The degree of motor cortical LTP could relate with the severity of motor symptoms in PSP.

13.
Hum Mol Genet ; 32(16): 2623-2637, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37364041

RESUMO

ß-propellers that bind polyphosphoinositides (PROPPINs) are an autophagy-related protein family conserved throughout eukaryotes. The PROPPIN family includes Atg18, Atg21 and Hsv2 in yeast and WD-repeat protein interacting with phosphoinositides (WIPI)1-4 in mammals. Mutations in the WIPI genes are associated with human neuronal diseases, including ß-propeller associated neurodegeneration (BPAN) caused by mutations in WDR45 (encoding WIPI4). In contrast to yeast PROPPINs, the functions of mammalian WIPI1-WIPI4 have not been systematically investigated. Although the involvement of WIPI2 in autophagy has been clearly shown, the functions of WIPI1, WIPI3 and WIPI4 in autophagy remain poorly understood. In this study, we comprehensively analyzed the roles of WIPI proteins by using WIPI-knockout (single, double and quadruple knockout) HEK293T cells and recently developed HaloTag-based reporters, which enable us to monitor autophagic flux sensitively and quantitatively. We found that WIPI2 was nearly essential for autophagy. Autophagic flux was unaffected or only slightly reduced by single deletion of WIPI3 (encoded by WDR45B) or WIPI4 but was profoundly reduced by double deletion of WIPI3 and WIPI4. Furthermore, we revealed variable effects of BPAN-related missense mutations on the autophagic activity of WIPI4. BPAN is characterized by neurodevelopmental and neurodegenerative abnormalities, and we found a possible association between the magnitude of the defect of the autophagic activity of WIPI4 mutants and the severity of neurodevelopmental symptoms. However, some of the BPAN-related missense mutations, which produce neurodegenerative signs, showed almost normal autophagic activity, suggesting that non-autophagic functions of WIPI4 may be related to neurodegeneration in BPAN.


Assuntos
Fosfatos de Fosfatidilinositol , Saccharomyces cerevisiae , Animais , Humanos , Saccharomyces cerevisiae/metabolismo , Células HEK293 , Fosfatos de Fosfatidilinositol/metabolismo , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia/genética , Mamíferos/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo
15.
Eur J Pharmacol ; 953: 175839, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37301318

RESUMO

We previously reported that brain α7 nicotinic acetylcholine receptors inhibited the rat micturition reflex. To elucidate the mechanisms underlying this inhibition, we focused on the relationship between α7 nicotinic acetylcholine receptors and hydrogen sulphide (H2S) because we found that H2S also inhibits the rat micturition reflex in the brain. Therefore, we investigated whether H2S is involved in the inhibition of the micturition reflex induced by the activation of α7 nicotinic acetylcholine receptors in the brain. Cystometry was performed in male Wistar rats under urethane anesthesia (0.8 g/kg, ip) to examine the effects of icv pre-treated GYY4137 (H2S donor, 1 or 3 nmol/rat) or aminooxyacetic acid (AOAA; non-selective H2S synthesis inhibitor, 3 or 10 µg/rat) on PHA568487 (α7 nicotinic acetylcholine receptor agonist, icv)-induced prolongation of intercontraction intervals. PHA568487 administration at a lower dose (0.3 nmol/rat, icv) had no significant effect on intercontraction intervals, while under pre-treatment with GYY4137 (3 nmol/rat icv), PHA568487 (0.3 nmol/rat, icv) significantly prolonged intercontraction intervals. PHA568487 at a higher dose (1 nmol/rat, icv) induced intercontraction interval prolongation, and the PHA568487-induced prolongation was significantly suppressed by AOAA (10 µg/rat, icv). The AOAA-induced suppression of the PHA568487-induced intercontraction interval prolongation was negated by supplementing H2S via GYY4137 at a lower dose (1 nmol/rat, icv) in the brain. GYY4137 or AOAA alone showed no significant effect on intercontraction intervals at each dose used in this study. These findings suggest a possible involvement of brain H2S in inhibiting the rat micturition reflex induced by activation of brain α7 nicotinic acetylcholine receptors.


Assuntos
Sulfeto de Hidrogênio , Receptores Nicotínicos , Ratos , Masculino , Animais , Micção , Receptor Nicotínico de Acetilcolina alfa7 , Sulfeto de Hidrogênio/farmacologia , Ratos Wistar , Encéfalo/metabolismo , Reflexo , Receptores Nicotínicos/metabolismo
16.
Int J Mol Sci ; 24(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37175592

RESUMO

This article provides a synopsis of current progress made in fundamental studies of lower urinary tract dysfunction (LUTD) after spinal cord injury (SCI) above the sacral level. Animal models of SCI allowed us to examine the effects of SCI on the micturition control and the underlying neurophysiological processes of SCI-induced LUTD. Urine storage and elimination are the two primary functions of the LUT, which are governed by complicated regulatory mechanisms in the central and peripheral nervous systems. These neural systems control the action of two functional units in the LUT: the urinary bladder and an outlet consisting of the bladder neck, urethral sphincters, and pelvic-floor striated muscles. During the storage phase, the outlet is closed, and the bladder is inactive to maintain a low intravenous pressure and continence. In contrast, during the voiding phase, the outlet relaxes, and the bladder contracts to facilitate adequate urine flow and bladder emptying. SCI disrupts the normal reflex circuits that regulate co-ordinated bladder and urethral sphincter function, leading to involuntary and inefficient voiding. Following SCI, a spinal micturition reflex pathway develops to induce an overactive bladder condition following the initial areflexic phase. In addition, without proper bladder-urethral-sphincter coordination after SCI, the bladder is not emptied as effectively as in the normal condition. Previous studies using animal models of SCI have shown that hyperexcitability of C-fiber bladder afferent pathways is a fundamental pathophysiological mechanism, inducing neurogenic LUTD, especially detrusor overactivity during the storage phase. SCI also induces neurogenic LUTD during the voiding phase, known as detrusor sphincter dyssynergia, likely due to hyperexcitability of Aδ-fiber bladder afferent pathways rather than C-fiber afferents. The molecular mechanisms underlying SCI-induced LUTD are multifactorial; previous studies have identified significant changes in the expression of various molecules in the peripheral organs and afferent nerves projecting to the spinal cord, including growth factors, ion channels, receptors and neurotransmitters. These findings in animal models of SCI and neurogenic LUTD should increase our understanding of pathophysiological mechanisms of LUTD after SCI for the future development of novel therapies for SCI patients with LUTD.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinária Hiperativa , Animais , Bexiga Urinária/fisiologia , Micção/fisiologia , Traumatismos da Medula Espinal/complicações , Medula Espinal
17.
Clin Case Rep ; 11(5): e7187, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37207088

RESUMO

The aim of this clinical report was to describe the improvement of masticatory disorders with the use of digital technology to simultaneously perform prosthodontic treatment of natural teeth and edentulous areas. Computer-guided implant surgery was performed, and crown prostheses and implant superstructures were fabricated simultaneously using digital technology.

18.
Entropy (Basel) ; 25(4)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37190412

RESUMO

Generative design is a system that automates part of the design process, but it cannot evaluate psychological issues related to shapes, such as "beauty" and "liking". Designers therefore evaluate and choose the generated shapes based on their experience. Among the design features, "complexity" is considered to influence "aesthetic preference". Although feature descriptors calculated from curvature can be used to quantify "complexity", the selection guidelines for curvature and feature descriptors have not been adequately discussed. Therefore, this study aimed to conduct a systematic classification of curvature and a feature descriptor of 3D shapes and to apply the results to the "complexity" quantification. First, we surveyed the literature on curvature and feature descriptors and conducted a systematic classification. To quantify "complexity", we used five curvatures (Gaussian curvature, mean curvature, Casorati curvature, shape index, and curvature index) and a feature descriptor (entropy of occurrence probability) obtained from the classification and compared them with the sensory evaluation values of "complexity". The results showed that the determination coefficient between the quantified and sensory evaluation values of "complexity" was highest when the mean curvature was used. In addition, the Casorati curvature tended to show the highest signal-to-noise ratio (i.e., a high determination coefficient irrespective of the parameters set in the entropy calculation). These results will foster the development of generative design of 3D shapes using psychological evaluation.

19.
Biochem Biophys Res Commun ; 658: 55-61, 2023 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-37023615

RESUMO

Otopetrins (Otop1-Otop3) belong to a newly identified family of proton (H+) channels activated by extracellular acidification. Here, we found that Zn2+ activates the mouse Otop3 (mOtop3) proton channels by using electrophysiological patch-clamp techniques. In mOtop3-expressing human embryonic kidney HEK293T cells, a biphasic inward mOtop3 H+ current comprising a fast transient current followed by a sustained current was observed upon extracellular acidification at pH 5.0. No significant activation of the mOtop3 channel was observed at pH 6.5 and 7.4, but interestingly, Zn2+ dose-dependently induced a sustained activation of mOtop3 under these pH conditions. Increasing the Zn2+ concentration had no effect on the reversal potential of the channel currents, suggesting that Zn2+ does not permeate through the mOtop3. The activation of the mOtop3 channel was specific to Zn2+ among divalent metal cations. Our findings reveal a novel modulatory mechanism of mOtop3 proton channels by Zn2+.


Assuntos
Prótons , Zinco , Animais , Camundongos , Humanos , Concentração de Íons de Hidrogênio , Células HEK293 , Potenciais da Membrana/fisiologia , Cátions Bivalentes , Zinco/farmacologia , Proteínas de Membrana/farmacologia
20.
Life Sci ; 325: 121738, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37121541

RESUMO

AIMS: Nerve growth factor (NGF) has been implicated as a key molecule of pathology-induced changes in C-fiber afferent nerve excitability, which contributes to the emergence of neurogenic detrusor overactivity due to spinal cord injury (SCI). It is also known that the second messenger signaling pathways activated by NGF utilize p38 Mitogen-Activated Protein Kinase (MAPK). We examined the roles of p38 MAPK on electrophysiological properties of capsaicin sensitive bladder afferent neurons with SCI mice. MAIN METHODS: We used female C57BL/6 mice and transected their spinal cord at the Th8/9 level. Two weeks later, continuous administration of p38 MAPK inhibitor (0.51 µg/h, i.t. for two weeks) was started. Bladder afferent neurons were labelled with a fluorescent retrograde tracer, Fast-Blue (FB), injected into the bladder wall three weeks after SCI. Four weeks after SCI, freshly dissociated L6-S1 dorsal root ganglion neurons were prepared and whole cell patch clamp recordings were performed in FB-labelled neurons. After recording action potentials or voltage-gated K+ currents, the sensitivity of each neuron to capsaicin was evaluated. KEY FINDINGS: In capsaicin-sensitive FB-labelled neurons, SCI significantly reduced the spike threshold and increased the number of action potentials during 800 ms membrane depolarization. Densities of slow-decaying A-type K+ (KA) and sustained delayed rectifier-type K+ (KDR) currents were significantly reduced by SCI. The reduction of KA, but not KDR, current density was reversed by the treatment with p38 MAPK inhibitor. SIGNIFICANCE: P38 MAPK plays an important role in hyperexcitability of capsaicin-sensitive bladder afferent neurons due to the reduction in KA channel activity in SCI mice.


Assuntos
Traumatismos da Medula Espinal , Bexiga Urinária , Camundongos , Feminino , Animais , Bexiga Urinária/metabolismo , Capsaicina/farmacologia , Capsaicina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Fator de Crescimento Neural/metabolismo , Camundongos Endogâmicos C57BL , Neurônios Aferentes , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Gânglios Espinais
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