RESUMO
ABSTRACT: Shibata, K, Yamaguchi, T, Takizawa, K, and Nosaka, K. Comparison in repetitions to failure between concentric-only and eccentric-only dumbbell arm curl exercise at four different relative intensities. J Strength Cond Res 37(9): 1754-1760, 2023-The repetitions to failure (RF) were compared between concentric-only (CON) and eccentric-only (ECC) arm curl exercise for different intensities based on CON and ECC 1 repetition maximum (1RM), respectively, with 2 different inter-repetition rests. Sixteen healthy male, university students (19-22 years) participated in 6 sessions. In sessions 1 and 2, CON and ECC 1RM strength were determined. In sessions 3 to 6, CON and ECC dumbbell arm curl exercises were performed until momentary failure at the intensity of either 70, 80, 90 or 95% of CON and ECC 1RM, respectively, with the inter-repetition rest of 3 seconds (R3) for one arm and 6 seconds (R6) for the other arm in a pseudo-randomized order. A significant ( p < 0.01) muscle contraction type × intensity interaction effect was evident for both R3 and R6 conditions. RF was greater ( p < 0.01) in ECC than in CON at 70% (34.2 ± 13.3 vs 20.9 ± 5.4), 80% (22.0 ± 6.7 vs 11.6 ± 2.7), 90% (10.1 ± 3.1 vs 5.2 ± 1.3), and 95% (6.8 ± 2.1 vs 2.7 ± 0.8) for R3. RF was also greater ( p < 0.01) for ECC than for CON at 80% (24.5 ± 8.1 vs 15.6 ± 3.6), 90% (10.8 ± 2.8 vs 7.2 ± 1.8) and 95% (6.7 ± 2.4 vs 3.9 ± 1.5) for R6, with greater ( p < 0.05) RF for R6 than R3. Significant ( p < 0.01) correlations in RF were evident between CON and ECC for R3 ( r = 0.86) and R6 ( r = 0.76). Equations to estimate 1RM were derived for CON and ECC at R3 and R6 (e.g., ECC 1RM = Load × 110.0/[110.5-RF] for R3). These results suggest that fatigue is less in ECC than in CON performed at the same relative intensity.
Assuntos
Terapia por Exercício , Contração Muscular , Humanos , Masculino , Contração Muscular/fisiologia , Músculo Esquelético/fisiologiaRESUMO
ABSTRACT: Shibata, K, Takizawa, K, Nosaka, K, and Mizuno, M. Effects of prolonging eccentric phase duration in parallel back-squat training to momentary failure on muscle cross sectional area, squat one repetition maximum, and performance tests in university soccer players. J Strength Cond Res 35(3): 668-674, 2021-This study aimed to compare 2 squat training programs repeated until momentary failure with different eccentric phase duration (2 seconds vs. 4 seconds) on the changes in muscle cross-sectional area, squat 1 repetition maximum (1RM), squat jump (SJ), and countermovement jump (CMJ) height, agility (T-test), and Yo-Yo intermittent recovery test (YY-IR2). Male university soccer players (19.9 ± 0.9 years, 172.2 ± 3.8 cm, 66.1 ± 6.6 kg) were randomly assigned to one of the 2 groups; CON for 2 seconds and ECC for 4 seconds (C2/E4, n = 11) or CON for 2 seconds and ECC for 2 seconds (C2/E2, n = 11). They performed parallel back-squat exercises twice a week for 6 weeks using 75% 1RM weight to momentary failure in each set for 3 sets with each protocol. Outcome measurements were taken before (Pre) and after 3 (Mid; 1RM, SJ, and CMJ only), and at 6 weeks (Post). One repetition maximum increased more (p < 0.05) for C2/E2 (Pre: 95.9 ± 12.2 kg, Mid: 108.2 ± 15.4 kg, Post: 113.6 ± 14.8 kg) than C2/E4 (95.5 ± 12.9 kg, 102.7 ± 15.6 kg, 105.5 ± 14.9 kg, respectively). Cross-sectional area (50% of the thigh length: 3.5 ± 2.8%), SJ (6.7 ± 8.9%) and CMJ height (6.3 ± 8.6%) increased similarly between C2/E2 and C2/E4, but no significant changes in T-test or YY-IR2 were evident in either group. These results suggest that increasing the ECC phase duration during squat exercises does not produce greater training effects when compared with a shorter ECC phase-duration program with momentary failure.
Assuntos
Desempenho Atlético , Treinamento Resistido , Corrida , Futebol , Humanos , Masculino , Força Muscular , Músculos , UniversidadesRESUMO
ABSTRACT: Shibata, K, Takizawa, K, Tomabechi, N, Nosaka, K, and Mizuno, M. Comparison between two volume-matched squat exercises with and without momentary failure for changes in hormones, maximal voluntary isometric contraction strength and perceived muscle soreness. J Strength Cond Res 35(11): 3063-3068, 2021-The present study compared 2 squat exercises with and without momentary failure (MF) for changes in blood hormones, maximal voluntary isometric contraction (MVC) strength, and perceived muscle soreness (SOR). Ten physically active male students performed squat exercises at 75% of their 1 repetition maximum in 2 conditions. First, they performed each set to MF for 3 sets, and 2 weeks later, performed the same number of repetitions in 6 sets without MF (NMF). The rate of perceived exertion was assessed at 30 minutes after exercise. Blood lactate, serum concentrations of growth hormone (GH), testosterone, insulin-like growth factor 1 (IGF-1) and cortisol, MVC strength, and SOR were measured before and after each exercise. Rate of perceived exertion was higher (p < 0.01) in MF (8.3 ± 1.2) than in NMF (4.1 ± 1.4). Blood lactate was greater (p < 0.01) at 5 minutes after MF (7.2 ± 0.7 mM·L-1) than NMF (3.6 ± 0.7 mM·L-1). At 30 minutes after exercise, GH (MF: 12.3 ± 8.3 ng·ml-1, NMF: 4.4 ± 5.2 ng·ml-1) and cortisol (MF: 19.0 ± 4.3 µg·dl-1, NMF: 14.2 ± 4.6 µg·dl-1) were greater (p < 0.01) for MF than NMF, but no significant differences were observed between conditions for testosterone and IGF-1. Maximal voluntary isometric contraction strength decrease (6.1 ± 8.8%) at 24 hours after exercise was evident only for MF, but SOR at 24 hours after exercise was similar between MF (4.8 ± 3.3 cm) and NMF (2.5 ± 2.4 cm) conditions. These results suggest that mechanical and metabolic stimulus to the muscles were greater for MF than NMF condition.
Assuntos
Contração Isométrica , Mialgia , Exercício Físico/fisiologia , Humanos , Hidrocortisona , Contração Isométrica/fisiologia , Masculino , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , PosturaRESUMO
OBJECTIVE: To investigate the effects of interactions between memory impairment, depressive symptoms, and anosognosia. METHODS: Anosognosia for memory impairment was assessed in 118 patients with Alzheimer's disease (AD), 47 patients with mild cognitive impairment (MCI), and 17 non-diagnosed controls (NC) using a questionnaire and evaluation of the anosognosia score as the discrepancy between ratings of the patient and a relative. Demographic characteristics, such as the relationship of the patient with the relative and the activities of daily living (ADL) were evaluated. Memory impairment was evaluated with the Rivermead Behavioral Memory Test (RBMT), depressive symptoms were evaluated using the Geriatric Depression Scale (GDS) 15 items version. RESULTS: In the MCI group, a stepwise multiple regression analysis showed an interaction between RBMT and GDS scores, and simple slope analysis indicated that scores for RBMT at low GDS (-1 standard deviation) were positively correlated with self-rated memory impairment. In the AD group, the relationship of the patient with the relative, ADL, and GDS and RBMT scores were associated with the anosognosia score. CONCLUSION: Patients with MCI who have no depressive symptoms may be able to more accurately evaluate their memory impairment than those who have depressive symptoms and patients with AD. The evaluation by relatives, depressive symptoms or ADL of patients may distort evaluation of anosognosia for memory impairment in patients with AD or MCI. It seems necessary to include not only depression scale scores but also results of objective memory tests in the patients' medical information for the correct assessment of anosognosia.
Assuntos
Atividades Cotidianas , Agnosia/diagnóstico , Agnosia/fisiopatologia , Doença de Alzheimer/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Depressão/fisiopatologia , Autoavaliação Diagnóstica , Transtornos da Memória/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Família , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Purpose To evaluate pineal volume in patients with Alzheimer disease (AD), patients with mild cognitive impairment (MCI), and healthy control subjects and to correlate the findings with results of cognitive testing and brain parenchymal volumes. Materials and Methods The ethics committee approved this retrospective study. The participants included 63 patients with AD, 33 patients with MCI, and 24 healthy control subjects. There were 36 men and 84 women, with a mean age (±standard deviation) of 76.7 years ± 7.6. The pineal gland volume and pineal parenchymal volume were measured by using three-dimensional volumetric magnetic resonance imaging (T1-weighted magnetization-prepared rapid gradient-echo sequence; spatial resolution, 0.9 × 0.98 × 0.98 mm). With age and total intracranial volume as covariates, analysis of covariance with the Bonferroni post hoc test was performed to compare the pineal volume among the AD, MCI, and control groups. Multiple regression analyses were used to identify predictor variables associated with pineal volume. Results The mean pineal gland volume in patients with AD (72.3 mm3 ± 5.4; 95% confidence interval [CI]: 61.5 mm3, 83.1 mm3) was significantly smaller than that in control subjects (102.1 mm3 ± 9.0; 95% CI: 84.4 mm3, 119.9 mm3) (P = .019). The mean pineal parenchymal volume in patients with AD (63.8 mm3 ± 4.2; 95% CI: 55.4 mm3, 72.1 mm3) was significantly smaller than that in patients with MCI (81.7 mm3 ± 5.8; 95% CI: 70.3 mm3, 93.1 mm3; P = .044) and control subjects (89.1 mm3 ± 6.9; 95% CI: 75.4 mm3, 102.9 mm3; P = .009). Multiple regression analyses demonstrated that the Mini-Mental State Examination score and total intracranial volume were significant independent predictors of both pineal gland volume and pineal parenchymal volume (P < .001). Conclusion Pineal volume reduction showed correlation with cognitive decline and thus might be useful to predict cognitive decline in patients with AD. © RSNA, 2017.
Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/epidemiologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Glândula Pineal/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Feminino , Humanos , Masculino , Glândula Pineal/patologia , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
AIMS: To investigate circadian gene expressions in the mouse bladder urothelium to establish an experimental model and study the functions of the circadian rhythm. METHODS: The gene expression rhythms of the clock genes, mechano-sensors such as Piezo1 and TRPV4, ATP release mediated molecules (ARMM) such as Cx26 and VNUT were investigated in mouse primary cultured urothelial cells (UCs) of wild-type (WT) and Clock mutant (ClockΔ19/Δ19 ) mice using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) and western blotting analysis. The long-term oscillation of the clock genes in UC was investigated by measuring bioluminescence from UC isolated from Period2luciferase knock-in mice (Per2::luc) and Per2::luc with ClockΔ19/Δ19 using a luminometer. The mRNA expression rhythms after treatment with Clock short interfering RNA (siRNA) were also measured to compare differences between Clock point mutations and Clock deficiency. RESULTS: The UCs from WT mice showed the time-dependent gene expressions for clock genes, mechano-sensors, and ARMM. The abundances of the products of these genes also correlated with the mRNA expression rhythms in UCs. The bioluminescence of Per2::Luc in UCs showed a circadian rhythm. By contrast, all the gene expressions rhythms observed in WT mice were abrogated in the ClockΔ19/Δ19 mice. Transfection with Clock siRNA in UCs had the same effect as the Clock mutation. CONCLUSIONS: We demonstrated that the time-dependent gene expressions, including clock genes, mechano-sensors, and ARMM, were reproducible in UCs. These findings demonstrated that UCs have the potential to progress research into the circadian functions of the lower urinary tract regulated by clock genes.
Assuntos
Proteínas CLOCK/metabolismo , Conexina 26/metabolismo , Canais Iônicos/metabolismo , Proteínas de Transporte de Nucleotídeos/metabolismo , Canais de Cátion TRPV/metabolismo , Urotélio/metabolismo , Animais , Proteínas CLOCK/genética , Células Cultivadas , Ritmo Circadiano/genética , Conexina 26/genética , Expressão Gênica , Canais Iônicos/genética , Camundongos , Proteínas de Transporte de Nucleotídeos/genética , Canais de Cátion TRPV/genética , Urotélio/citologiaRESUMO
Takizawa, K, Yamaguchi, T, and Shibata, K. Warm-up exercises may not be so important for enhancing submaximal running performance. J Strength Cond Res 32(5): 1383-1390, 2018-The purpose of this study was to determine an appropriate warm-up intensity for enhancing performance in submaximal running at 90% vV[Combining Dot Above]O2max (it assumes 3,000-5,000 m in track events). Seven trained male university athletes took part in this study (age: 21.3 ± 2.1 years, height: 169.3 ± 4.7 cm, body mass: 58.4 ± 5.6 kg, V[Combining Dot Above]O2max: 73.33 ± 5.46 ml·kg·min). Each subject ran on a treadmill at 90% vV[Combining Dot Above]O2max until exhaustion after 1 of 4 warm-up treatments. The 4 warm-up treatments were no warm-up, 15 minutes running at 60% vV[Combining Dot Above]O2max, at 70% vV[Combining Dot Above]O2max, and at 80% vV[Combining Dot Above]O2max. The running performance was evaluated by time to exhaustion (TTE). V[Combining Dot Above]O2, and vastus lateralis muscle temperature were also measured. There were no significant differences in TTE among the warm-up exercises (p > 0.05). V[Combining Dot Above]O2 in no warm-up showed slower reaction than the other warm-up exercises. Regarding, the vastus lateralis muscle temperature immediately after warm-up, no warm-up was significantly (p < 0.01) lower compared with the other warm-up exercises. Our results suggested that submaximal running performance was not affected by the presence or absence of a warm-up or by warm-up intensity, although physiological changes occurred.
Assuntos
Desempenho Atlético/fisiologia , Corrida/fisiologia , Exercício de Aquecimento/fisiologia , Atletas , Teste de Esforço , Humanos , Masculino , Força Muscular/fisiologia , Consumo de Oxigênio/fisiologia , Músculo Quadríceps/fisiologia , Adulto JovemRESUMO
BACKGROUND: The Executive Interview (EXIT25), the executive clock-drawing task (CLOX1), and the Frontal Assessment Battery (FAB) are used to assess executive function at the bedside. These tests assess distinct psychometric properties. The aim of this study was to examine differences in the neural correlates of the EXIT25, CLOX1, and FAB based on magnetic resonance imaging. METHODS: Fifty-eight subjects (30 with Alzheimer's disease, 10 with mild cognitive impairment, and 18 healthy controls) participated in this study. Multiple regression analyses were performed to examine the brain regions correlated with the EXIT25, CLOX1, and FAB scores. Age, gender, and years of education were included as covariates. Statistical thresholds were set to uncorrected P-values of 0.001 at the voxel level and 0.05 at the cluster level. RESULTS: The EXIT25 score correlated inversely with the regional grey matter volume in the left lateral frontal lobe (Brodmann areas 6, 9, 44, and 45). The CLOX1 score correlated positively with the regional grey matter volume in the right orbitofrontal cortex (Brodmann area 11) and the left supramarginal gyrus (Brodmann area 40). The FAB score correlated positively with the regional grey matter volume in the right precentral gyrus (Brodmann area 6). The left lateral frontal lobe (Brodmann area 9) and the right lateral frontal lobe (Brodmann area 46) were identified as common brain regions that showed association with EXIT25, CLOX1, and FAB based only a voxel-level threshold. CONCLUSIONS: The results of this study suggest that the EXIT25, CLOX1, and FAB may be associated with the distinct neural correlates of the frontal cortex.
Assuntos
Doença de Alzheimer/fisiopatologia , Encéfalo/diagnóstico por imagem , Função Executiva/fisiologia , Lobo Frontal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Testes Neuropsicológicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Encéfalo/fisiopatologia , Feminino , Avaliação Geriátrica/métodos , Humanos , Entrevista Psicológica/métodos , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Desempenho PsicomotorRESUMO
AIMS: The pathophysiologies of nocturia (NOC) and nocturnal polyuria (NP) are multifactorial and their etiologies remain unclear in a large number of patients. Clock genes exist in most cells and organs, and the products of Clock regulate circadian rhythms as representative clock genes. Clock genes regulate lower urinary tract function, and a newly suggested concept is that abnormalities in clock genes cause lower urinary tract symptoms. In the present study, we investigated the voiding behavior of Clock mutant (ClockΔ19/Δ19 ) mice in order to determine the effects of clock genes on NOC/NP. METHODS: Male C57BL/6 mice aged 8-12 weeks (WT) and male C57BL/6 ClockΔ19/Δ19 mice aged 8 weeks were used. They were bred under 12 hr light/dark conditions for 2 weeks and voiding behavior was investigated by measuring water intake volume, urine volume, urine volume/void, and voiding frequency in metabolic cages in the dark and light periods. RESULTS: No significant differences were observed in behavior patterns between ClockΔ19/Δ19 and WT mice. ClockΔ19/Δ19 mice showed greater voiding frequencies and urine volumes during the sleep phase than WT mice. The diurnal change in urine volume/void between the dark and light periods in WT mice was absent in ClockΔ19/Δ19 mice. Additionally, functional bladder capacity was significantly lower in ClockΔ19/Δ19 mice than in WT mice. CONCLUSIONS: We demonstrated that ClockΔ19/Δ19 mice showed the phenotype of NOC/NP. The ClockΔ19/Δ19 mouse may be used as an animal model of NOC and NP. Neurourol. Urodynam. 36:1034-1038, 2017. © 2016 Wiley Periodicals, Inc.
Assuntos
Proteínas CLOCK/genética , Ritmo Circadiano/genética , Noctúria/genética , Poliúria/genética , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The purpose of this study was to clarify the acute effect of dynamic stretching (DS) on relative high-intensity endurance running performance. The endurance running performances of 7 well-trained middle- or long-distance male runners were assessed on a treadmill after 2 types of pretreatment. The pretreatments were nonstretching (NS) and DS treatment. In the DS treatment, DS was performed as 1 set of 10 repetitions as quickly as possible for the 5 muscle groups in lower extremities. The endurance running performances were evaluated by time to exhaustion (TTE) and total running distance (TRD) during running at a velocity equivalent to 90% maximal oxygen uptake (VO2max) in each subject. The oxygen uptake (VO2) during running was measured as an index of running economy (RE). The TTE (928.6 ± 215.0 seconds) after DS treatment was significantly (p < 0.01) more prolonged compared with that (785.3 ± 206.2 seconds) after NS. The TRD (4,301.2 ± 893.8 m) after DS treatment was also significantly (p < 0.01) longer than that (3,616.9 ± 783.3 m) after NS. The changes in the VO2 during running, however, did not significantly (p > 0.05) differ between the pretreatments. The results demonstrated that the DS treatment improved the endurance performance of running at a velocity equivalent to 90% VO2max in well-trained male runners, although it did not change the RE. This running velocity is equivalent to that for a 3,000- or 5,000-m race. Our finding suggests that performing DS during warm-up before a race is effective for improving performance.
Assuntos
Desempenho Atlético/fisiologia , Exercícios de Alongamento Muscular , Resistência Física/fisiologia , Corrida/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Adulto JovemRESUMO
BACKGROUND: The aim of the study was to develop the Japanese versions of Executive Interview (J-EXIT25) and Executive Clock Drawing Task (J-CLOX) and to evaluate the aspects of executive function that these two tests will be examining. METHODS: The concurrent validity and reliability of J-EXIT25 and J-CLOX were first examined in all participants (n = 201). Next, the relationship between the two tests was examined using receiver operating characteristic (ROC), correlation, and regression analyses in healthy participants (n = 45) and participants with mild cognitive impairment (n = 36) and dementia (n = 95). RESULTS: Satisfactory concurrent validity and reliability of J-EXIT25 and J-CLOX were shown. ROC analysis indicated that J-EXIT25 and J-CLOX1 were superior to the Frontal Assessment Battery, but inferior to the Mini-Mental State Examination (MMSE), in discriminating between non-dementia and dementia. J-EXIT25, J-CLOX1, and J-CLOX2 scores were significantly correlated with age, scores on the MMSE, Instrumental Activities of Daily Living (IADL) and Physical Self-Maintenance Scale (PSMS), and care level. In stepwise regression analyses of IADL scores, MMSE and J-EXIT25 were significantly independent predictors in men, and MMSE, age, and J-CLOX1 were significantly independent predictors in women. J-EXIT25, MMSE, and J-CLOX1 were significantly independent predictors in stepwise regression analysis of PSMS scores, and J-EXIT25 was the only significantly independent predictor in stepwise regression analysis of care level. CONCLUSIONS: J-EXIT25 and J-CLOX are valid and reliable instruments for assessment of executive function in older people. The present results suggest that these tests have common and distinct psychometric properties in the assessment of executive function.
Assuntos
Atividades Cotidianas/psicologia , Transtornos Cognitivos , Função Executiva , Entrevista Psicológica , Psicometria , Autocuidado/psicologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/psicologia , Demência , Feminino , Avaliação Geriátrica/métodos , Humanos , Testes de Inteligência/normas , Entrevista Psicológica/métodos , Entrevista Psicológica/normas , Masculino , Psicometria/métodos , Psicometria/normas , Curva ROC , Análise de Regressão , Reprodutibilidade dos Testes , Fatores Sexuais , Estatística como Assunto , TraduçãoRESUMO
Background: Mild behavioral impairment (MBI) and loneliness are associated with cognitive decline and an increased risk of dementia. Objective: Our aim was to examine the validity of the Japanese version of the MBI checklist (MBI-C) and investigate the relationship between loneliness and MBI. Methods: The participants in this cross-sectional study included 5 cognitively normal persons and 75 persons with mild cognitive impairment. MBI-C and the revised University of California at Los Angeles loneliness scale (LS) were used to assess MBI and loneliness, respectively. Diagnostic performance of MBI-C was examined using receiver operating characteristic analysis. The relationship between MBI-C and LS was examined using multiple linear regression in 67 subjects who were assessed with both scales, with MBI-C total or domain score as the dependent variable and LS as the independent variable, adjusted for age, gender, living situation, presence of visual and hearing impairment, and Mini-Mental State Examination score. Results: Per the Youden index, in this mostly MCI sample, the optimal MBI-C cut-off score was 5.5 with sensitivity 0.917 and specificity 0.949. In multiple linear regression analysis, LS score was detected as a significant predictor of MBI-C total scores, and MBI-C decreased motivation, affective dysregulation, and abnormal thought and perception scores. Conclusions: The caregiver-rated Japanese MBI-C has excellent diagnostic performance. Loneliness is associated with a greater MBI burden, especially in the decreased motivation, affective dysregulation, and abnormal thought and perception domains. Interventions for loneliness in older people may have the potential to improve MBI.
Assuntos
Disfunção Cognitiva , Solidão , Humanos , Idoso , Estudos Transversais , Lista de Checagem , Japão , Testes Neuropsicológicos , Disfunção Cognitiva/psicologiaRESUMO
Microglia survey the brain environment by sensing several types of diffusible molecules, among which extracellular nucleotides released/leaked from damaged cells have central roles. Microglia sense ATP or other nucleotides by multiple P2 receptors, after which they change into several different phenotypes. However, so far, it is largely unknown whether microglia themselves release ATP and, if so, by what mechanism. Here we show that exocytosis is the mechanism by which microglia release ATP. When we stimulated microglia with ionomycin, they released ATP and the release was dependent on Ca²âº, vesicular Hâº-ATPase, or SNAREs but independent of connexin/pannexin hemichannels. VNUT was found to be expressed in microglia and exhibited no colocalization with lysosome. We also visualized the exocytosis of ATP by a quinacrine-based fluorescent time-lapse imaging. Moreover, we found that lipopolysaccharide increased the ionomycin-induced release of ATP, which was dependent on the increase in VNUT. Taken together, our data suggested that exocytosis is the mechanism of ATP release from microglia. When activated, they would release ATP by increasing VNUT-dependent exocytotic mechanisms.
Assuntos
Trifosfato de Adenosina/metabolismo , Exocitose/fisiologia , Microglia/metabolismo , Animais , Animais Recém-Nascidos , Células Cultivadas , Microglia/citologia , Ratos , Ratos WistarRESUMO
OBJECTIVES: Postoperative delirium is a common psychiatric disorder among patients who undergo cardiac surgery. Although several studies have investigated risk factors for delirium after cardiac surgery, the association between delirium and cerebral white-matter hyperintensities (WMH) on magnetic resonance (MR) imaging has not been previously studied. The aim of this study was to identify general risk factors for delirium, as well as to examine the specific relationship between WMH and delirium. DESIGN: Retrospective chart review. SETTING: University hospital. PARTICIPANTS: A total of 130 patients who underwent cardiac surgery. MEASUREMENTS: Variables recorded included patient demographics, comorbidities, mental health, laboratory data, surgical information, and cerebrovascular disease. The presence of WMH was assessed using MR images. Two groups of patients were compared (patients with and without delirium) using both univariate and multiple logistic analyses. RESULTS: Delirium occurred in 18 patients (13.8%) and patients with delirium were significantly older than patients who did not develop delirium. The prevalence of severe WMH (Fazekas score = 3) was significantly higher in patients with delirium. Three independent predictors of delirium were identified: abnormal creatinine (odds ratio [OR]: 4.5; 95% confidence interval [CI]: 1.4-13.9), severe WMH (OR: 3.9; 95% CI: 1.2-12.5), and duration of surgery (OR: 1.4; 95% CI: 1.0-1.8). CONCLUSIONS: The results of this study suggest that white-matter abnormality is one of the most important risk factors for development of delirium after cardiac surgery. These factors can be used for prediction and prevention of delirium following cardiac surgery.
Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Delírio/patologia , Fibras Nervosas Mielinizadas/patologia , Complicações Pós-Operatórias/patologia , Idoso , Envelhecimento/patologia , Envelhecimento/psicologia , Estudos de Casos e Controles , Delírio/complicações , Delírio/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Complicações Pós-Operatórias/diagnóstico , Estudos Retrospectivos , Fatores de RiscoRESUMO
BACKGROUND: The aim of this study was to identify the neural correlates of each component of the clock drawing test (CDT) in drug-naïve patients with Alzheimer's disease (AD) using single photon emission computed tomography. METHODS: The participants were 95 drug-naïve patients with AD. The Rouleau CDT was used to score the clock drawings. The score for the Rouleau CDT (R total) is separated into three components: the scores for the clock face (R1), the numbers (R2), and the hands (R3). A multiple regression analysis was performed to examine the relationship of each score (i.e. R total, R1, R2, and R3) with regional cerebral blood flow (rCBF). Age, gender, and education were included as covariates. The statistical threshold was set to a family-wise error (FWE)-corrected p value of 0.05 at the voxel level. RESULTS: The R total score was positively correlated with rCBF in the bilateral parietal and posterior temporal lobes and the right middle frontal gyrus. R1 was not significantly positively correlated with rCBF, R2 was significantly positively correlated with rCBF in the right posterior temporal lobe and the left posterior middle temporal lobe, and R3 was significantly positively correlated with rCBF in the bilateral parietal lobes, the right posterior temporal lobe, the right middle frontal gyrus, and the right occipital lobe. CONCLUSIONS: Various brain regions were associated with each component of the CDT. These results suggest that an assessment of these components is useful for the detection of localization of brain damage.
Assuntos
Doença de Alzheimer/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Testes Neuropsicológicos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Fluxo Sanguíneo Regional , Análise de Regressão , Fatores SocioeconômicosRESUMO
Background: Cancer-associated thrombosis (CAT) is a common complication of cancer and has received increasing attention; the Khorana Risk Score (KRS) is a recommended but insufficient risk assessment model for CAT. We propose a novel Kagoshima-DVT score (KDS) to predict preoperative deep vein thrombosis (DVT). This scoring method scores D-dimer ≥1.5 µg/mL, age ≥60 years, female sex, ongoing glucocorticoids, cancer with high risk of DVT, and prolonged immobility. The purpose of this study was to compare the performance of the KDS and KRS in predicting CAT in patients with gastrointestinal cancer. MethodsâandâResults: In all, 250 patients without a history of thrombosis who received their first chemotherapy for gastrointestinal cancer were divided into low- (48.0%), intermediate- (38.8%), and high-risk (13.2%) groups for CAT development by the KDS. The patients' median age was 67 years and 63.2% were men. In all, 61 (27.1%) patients developed CAT (17.6%, 35.3%, and 36.4% of patients in the low-, intermediate, and high-risk groups, respectively; log-rank P=0.006). The area under the time-dependent receiver operating characteristic curve for CAT occurrence within 1 year was larger for the KDS than KRS (0.653 vs. 0.494). Conclusions: A high KDS at the start of first chemotherapy is a risk indicator for CAT development during chemotherapy. Moreover, the KDS is more useful than the KRS in predicting CAT risk.
RESUMO
A 55-year-old male underwent surgery for thymus gland tumors six years previously, and for lung and pancreas tumors three years previously, which were pathologically diagnosed as neuroendocrine tumors (NETs). During routine medical checkups, a giant negative T-wave was observed on the electrocardiogram. Echocardiography revealed a tumor at the apex. A surgical biopsy was performed; the tumor was diagnosed as a cardiac metastasis of NETs, and chemotherapy was initiated. Two years later, echocardiography confirmed that the tumor had not increased in size. A 2-year follow-up of NETs cardiac metastasis is rare; we therefore report this case. Learning objective: Neuroendocrine tumors are considered slowly progressing tumors, but despite the presence of cardiac metastasis, accurate diagnosis and appropriate treatment have allowed the patient to survive the disease for more than two years.
RESUMO
Since gonadal female hormones act on and protect neurons, it is well known that the female brain is less vulnerable to stroke or other brain insults than the male brain. Although glial functions have been shown to affect the vulnerability of the brain, little is known if such a sex difference exists in glia, much less the mechanism that might cause gender-dependent differences in glial functions. In this study, we show that in vitro astrocytes obtained from either female or male pups show a gonadal hormone-independent phenotype that could explain the gender-dependent vulnerability of the brain. Female spinal astrocytes cleared more glutamate by GLAST than male ones. In addition, motoneurons seeded on female spinal astrocytes were less vulnerable to glutamate than those seeded on male ones. It is suggested that female astrocytes uptake more glutamate and reveal a stronger neuroprotective effect against glutamate than male ones. It should be noted that such an effect was independent of gonadal female hormones, suggesting that astrocytes have cell-autonomous regulatory mechanisms by which they transform themselves into appropriate phenotypes.
Assuntos
Astrócitos/citologia , Astrócitos/metabolismo , Ácido Glutâmico/metabolismo , Animais , Citoproteção , Feminino , Masculino , Neurônios Motores/citologia , Neurônios Motores/metabolismo , Ratos , Ratos WistarRESUMO
The aim of this study was to examine the effect of toki-shakuyaku-san (TSS) on mild cognitive impairment (MCI) and Alzheimer's disease (AD) using single-photon emission computed tomography (SPECT). All subjects were administered TSS (7.5 g/day) for eight weeks. SPECT and evaluations using the Mini Mental State Examination (MMSE), Neuropsychiatric Inventory, and Physical Self-Maintenance Scale were performed before and after treatment with TSS. Three patients with MCI and five patients with AD completed the study. No adverse events occurred during the study period. After treatment with TSS, regional cerebral blood flow (rCBF) in the posterior cingulate was significantly higher than that before treatment. No brain region showed a significant decrease in rCBF. TSS treatment also tended to improve the score for orientation to place on the MMSE. These results suggest that TSS could be useful for treatment of MCI and AD.
RESUMO
BACKGROUND: There has been a growing need for a cognitive assessment tool that can be used for older adults with schizophrenia in clinical settings. The clock-drawing test (CDT) is a brief cognitive test that covers a wide range of cognitive function. Although it is widely used to assess patients with dementia, limited data are available on its usefulness in older patients with schizophrenia. Thus, we investigated the psychometric properties of the CDT and their relationship with life functions to examine the test's usefulness for assessing cognitive function in older adults with schizophrenia. METHODS: Seventy-three older adults with chronic schizophrenia who had been hospitalized for over 1 year participated in the study. We adopted the executive clock-drawing task for administration and scoring of the CDT, which consists of free-drawn and copy conditions. The Mini-Mental State Examination and the Brief Assessment of Cognition in Schizophrenia were administered. Symptom severity and life functions were assessed with the Positive and Negative Syndrome Scale and the Life Skills Profile, respectively. RESULTS: Both free-drawn and copy scores significantly correlated with the Mini-Mental State Examination score and the Brief Assessment of Cognition in Schizophrenia composite score. These scores also significantly correlated with symptom severity and length of current hospitalization. Stepwise regression analysis showed that only the copy score, together with symptom severity, predicted the Life Skills Profile score. CONCLUSIONS: The CDT can assess cognitive function in older adults with schizophrenia. Moreover, CDT performance is associated with life functions independent from other clinical variables. These results suggest that the CDT is a useful cognitive assessment tool for this population.