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BACKGROUND: Atrial fibrillation (AF) is a strong risk factor for Alzheimer's disease (AD) independent of ischemic stroke. However, the clinicopathological impact of AF on the severity of AD has not been well elucidated. We aimed to investigate the clinical differences between dementia patients with AF and those without AF by means of imaging data. METHODS: Following approval from the institutional ethics committee, patients with newly diagnosed AD or amnestic mild cognitive impairment (aMCI) were retrospectively screened (n = 170, 79.5 ± 7.4 years old). Cognitive function was assessed using the Mini-Mental State Examination (MMSE). Based on the MRI data, the cerebral volume, cerebral microbleeds (CMBs), periventricular white matter lesions (WMLs), and deep WMLs were evaluated. The regional cerebral blood flow (rCBF) was measured using 123I-IMP SPECT. RESULTS: Of the patients, 14 (8.2%) and 156 (91.8%) had AF (AF group) and sinus rhythm (SR group), respectively. The AF group had significantly lower MMSE scores than the SR group (average [standard deviation (SD)]: 19.4 [4.4] and 22.0 [4.4], respectively; p = 0.0347). Cerebral volume and CMBs did not differ between the two groups. The periventricular WMLs, but not the deep WMLs, were significantly larger in the AF group than in the SR group (mean [SD] mL: 6.85 [3.78] and 4.37 [3.21], respectively; p = 0.0070). However, there was no significant difference in rCBF in the areas related to AD pathology between the two groups. CONCLUSION: AD and aMCI patients with AF showed worse cognitive decline along with larger periventricular WMLs compared to those with SR, although the reduction of rCBF was not different between patients with AF and SR. The white matter lesions may be a more important pathology than the impairment of cerebral blood flow in dementia patients with AF. A larger study is needed to confirm our findings in the future.
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Doença de Alzheimer , Fibrilação Atrial , Disfunção Cognitiva , Humanos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/patologia , Encéfalo/patologia , Estudos Retrospectivos , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Imageamento por Ressonância Magnética/métodosRESUMO
BACKGROUND AND PURPOSE: In terms of the gut-brain axis, constipation has been considered to be an important factor of neurodegenerative diseases, although the exact mechanism is still controversial. Herein, we aimed to investigate the contribution of constipation to the progression of dementia in a retrospective study. METHODS: Patients of Alzheimer's disease(AD) and amnestic mild cognitive impairment were consecutively screened between January 2015 and December 2020, and those of whom brain MRI and neuropsychological tests were performed twice were enrolled in this study. Participants were classified into with constipation (Cons[+], n = 20) and without constipation (Cons[-], n = 64) groups. Laboratory data at the first visit were used. Regression analysis was performed in MMSE, ADAS-Cog, and the volumes of hippocampus on MRI-MPRAGE images and deep white matter lesions (DWMLs) on MRI-FLAIR images obtained at two different time points. RESULTS: The main finding was that the Cons[+] group showed 2.7 times faster decline in cognitive impairment compared with the Cons[-] group, that is, the liner coefficients of ADAS-Cog were 2.3544 points/year in the Cons[+] and 0.8592 points/year in the Cons[-] groups. Ancillary, changes of DWMLs showed significant correlation with the time span (p < 0.01), and the liner coefficients of DWMLs were 24.48 ml/year in the Cons[+] and 14.83 ml/year in the Cons[-] group, although annual rate of hippocampal atrophy was not different between the two groups. Moreover, serum homocysteine level at baseline was significantly higher in the Cons[+] group than Cons[-] group (14.6 ± 6.4 and 11.5 ± 4.2 nmol/ml, respectively: p = 0.03). CONCLUSION: There is a significant correlation between constipation and faster progression of AD symptoms along with expansion of DWMLs.
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Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/patologia , Estudos Retrospectivos , Disfunção Cognitiva/patologia , Testes Neuropsicológicos , Imageamento por Ressonância Magnética , Constipação Intestinal , Progressão da DoençaRESUMO
Both objective and perceived social isolations were associated with future cognitive decline and increase risk of Alzheimer's disease (AD). However, the impacts of perceived social isolation depending on different clinical stages of AD have not been elucidated. The aim of this study was to investigate the influence of perceived social isolation or loneliness on brain structure and future cognitive trajectories in patients who are living with or are at risk for AD. A total of 176 elderly patients (mean age of 78 years) who had complaint of memory problems (39 subjective cognitive decline [SCD], 53 mild cognitive impairment [MCI], 84 AD) underwent structural MRI and neuropsychological testing. Loneliness was measured by one binary item question "Do you often feel lonely?." Voxel-based morphometry was conducted to evaluate regional gray matter volume (rGMV) difference associated with loneliness in each group. To evaluate individual differences in cognitive trajectories based on loneliness, subgroup analysis was performed in 51 patients with AD (n = 23) and pre-dementia status (SCD-MCI, n = 28) using the longitudinal scores of Alzheimer's Disease Assessment Scale-cognitive component-Japanese version (ADAS-Jcog). Whole brain VBM analysis comparing lonely to non-lonely patients revealed loneliness was associated with decreased rGMV in bilateral thalamus in SCD patients and in the left middle occipital gyrus and the cerebellar vermal lobules I - V in MCI patients. Annual change of ADAS-Jcog in patients who reported loneliness was significantly greater comparing to these non-lonely in SCD-MCI group, but not in AD group. Our results indicate that perceived social isolation, or loneliness, might be a comorbid symptom of patients with SCD or MCI, which makes them more vulnerable to the neuropathology of future AD progression.
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Doença de Alzheimer , Disfunção Cognitiva , Idoso , Doença de Alzheimer/diagnóstico , Encéfalo/patologia , Cognição , Disfunção Cognitiva/diagnóstico , Humanos , Isolamento SocialRESUMO
Nutritional supplementation with medium-chain triglycerides (MCTs) has the potential to increase memory function in elderly patients with frailty and dementia. Our aim was to investigate the effects of MCT on cognitive and gait functions and their relationships with focal brain metabolism and functional connectivity even in healthy older adults. Participants were blindly randomized and allocated to two groups: 18 g/day of MCT oil and matching placebo formula (control) administered as a jelly stick (6 g/pack, ingested three times a day). Gait analysis during the 6-m walk test, cognition, brain focal glucose metabolism quantified by 18F-fluorodeocyglucose positron emission tomography, and magnetic resonance imaging-based functional connectivity were assessed before and after a 3-month intervention. Sixty-three healthy, normal adults (females and males) were included. Compared with the control group, the MCT group showed better balance ability, as represented by the lower Lissajous index (23.1 ± 14.4 vs. 31.3 ± 18.9; P < 0.01), although no time × group interaction was observed in cognitive and other gait parameters. Moreover, MCT led to suppressed glucose metabolism in the right sensorimotor cortex compared with the control (P < 0.001), which was related to improved balance (r = 0.37; P = 0.04) along with increased functional connectivity from the ipsilateral cerebellar hemisphere. In conclusion, a 3-month MCT supplementation improves walking balance by suppressing glucose metabolism, which suggests the involvement of the cerebro-cerebellar network. This may reflect, at least in part, the inverse reaction of the ketogenic switch as a beneficial effect of long-term MCT dietary treatment.
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Encéfalo , Marcha , Idoso , Feminino , Glucose , Humanos , Masculino , Redes e Vias Metabólicas , TriglicerídeosRESUMO
Recently, type 2 diabetes mellitus (T2DM) has been reported to be strongly associated with Alzheimer's disease (AD). This is partly due to insulin resistance in the brain. Insulin signaling and the number of insulin receptors may decline in the brain of T2DM patients, resulting in impaired synaptic formation, neuronal plasticity, and mitochondrial metabolism. In AD patients, hypometabolism of glucose in the brain is observed before the onset of symptoms. Amyloid-ß accumulation, a main pathology of AD, also relates to impaired insulin action and glucose metabolism, although ketone metabolism is not affected. Therefore, the shift from glucose metabolism to ketone metabolism may be a reasonable pathway for neuronal protection. To promote ketone metabolism, medium-chain triglyceride (MCT) oil and a ketogenic diet could be introduced as an alternative source of energy in the brain of AD patients.
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Doença de Alzheimer/dietoterapia , Doença de Alzheimer/epidemiologia , Óleo de Coco/uso terapêutico , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/epidemiologia , Dieta Cetogênica/métodos , Óleo de Palmeira/uso terapêutico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Comorbidade , Diabetes Mellitus Tipo 2/metabolismo , Metabolismo Energético , Glucose/metabolismo , Humanos , Insulina/metabolismo , Resistência à Insulina , Cetonas/metabolismoRESUMO
Early brain injury (EBI) is closely linked to the development of delayed cerebral ischemia and poor outcomes after aneurysmal subarachnoid hemorrhage (SAH). This study aimed to evaluate the neuroprotective effect of neurotropin on EBI in a murine model of SAH. Twenty-four C57BL/6N mice were treated with intraperitoneal injections of either saline or 2.4 units of neurotropin at 1 h after SAH induction and for 3 days consecutively. SAH was created by an endovascular perforation method. In addition to the assessment of cerebral infarction and survival rate, motor and neurocognitive functions were also measured after SAH. Compared to the saline control group, the neurotropin group showed better recovery from locomotive and neurological declines after SAH. The neurotropin group also showed lower rates of post-SAH acute cerebral infarction and better memory and route-learning scores (p < 0.05). Meanwhile, there was no significant between-group differences in the overall mortality, hemodynamic parameters, or body weights. In conclusion, post-event treatment with neurotropin could be protective against EBI, lowering the incidence of ischemia and improving some motor and neurocognitive functions after SAH.
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OBJECTIVE: Optimizing cardiac stroke volume during high-risk surgical anesthesia is of particular interest with regard to a therapeutic target to reduce the incidence of postoperative complications. However, intensive fluid management in critically ill small animals with pulmonary hypertension (PH) has been empirically performed, and thus it can be challenging. Stroke volume variation (SVV) has been used as a dynamic preload predictor of fluid responsiveness. We hypothesized that if SVV exhibited robust reliability in the setting of hemodynamically unstable condition, it would provide more precise information on fluid resuscitation to translate it into veterinary anesthesia. Thus the aim of this study was to investigate the utility of SVV measured by the electrical velocimetry (EV) method for predicting fluid responsiveness in dogs with PH. METHODS: Sixteen dogs undergoing emergency abdominal surgery and diagnosed with PH secondary to myxomatous mitral valve disease (MMVD) on preoperative transthoracic echocardiogram were included. Dogs were randomly assigned to 2 groups with and without inotropic cardiac support with dobutamine. Hemodynamic measurements including stroke volume and SVV derived from the EV device were performed under general anesthesia before (baseline) and after surgery (fluid challenge with a colloid solution defined by a SV increase of ≥ 10%). RESULTS: In both groups, SVV elevated significantly after abdominal surgery compared with baseline. In dobutamine infused group, the SVV values decreased significantly after fluid challenge (P < 0.05) with a greater number of responders than saline infused control group (P < 0.01). Receiver operating curve analysis of SVV confirmed high positive predictive value for dogs during dobutamine infusion (P < 0.05; cut-off value of 15%; specificity 90%, sensitivity 82%). CONCLUSIONS: Noninvasive EV monitoring may be useful for the prediction of fluid responsiveness in critically ill dogs with left-sided heart failure-related PH. This normalization of dynamic preload indices, which could be achieved more precisely under inotropic support, may prevent further detrimental consequence of fluid loading.
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Abdome/cirurgia , Anestesia , Doenças do Cão/cirurgia , Tratamento de Emergência , Hidratação , Hipertensão Pulmonar/terapia , Hipertensão Pulmonar/veterinária , Procedimentos Cirúrgicos Operatórios , Animais , Cães , Hemodinâmica , Hipertensão Pulmonar/fisiopatologia , Curva ROC , Fatores de Risco , Volume SistólicoRESUMO
Alzheimer's disease (AD) is a common neurodegenerative disease and a major contributor to progressive cognitive impairment in an aging society. As the pathophysiology of AD involves chronic neuroinflammation, the resolution of inflammation and the group of lipid mediators that actively regulate it-i.e., specialized pro-resolving lipid mediators (SPMs)-attracted attention in recent years as therapeutic targets. This review focuses on the following three specific SPMs and summarizes their relationships to AD, as they were shown to effectively address and reduce the risk of AD-related neuroinflammation: maresin 1 (MaR1), resolvin D1 (RvD1), and neuroprotectin D1 (NPD1). These three SPMs are metabolites of docosahexaenoic acid (DHA), which is contained in fish oils and is thus easily available to the public. They are expected to become incorporated into promising avenues for preventing and treating AD in the future.
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Doença de Alzheimer/tratamento farmacológico , Ácidos Docosa-Hexaenoicos/uso terapêutico , Animais , Ácidos Docosa-Hexaenoicos/química , HumanosRESUMO
Background: Decreased bone mineral density (BMD) was associated with poorer cognitive function and increased risk of Alzheimer's disease (AD). However, objective evidence for the relationship between osteoporosis and AD in humans has not been extensively described. Objectives: We aimed to evaluate the relationships between BMD and the cortical volumes of brain regions vulnerable to AD; hippocampus, parahippocampal gyrus, precuneus, posterior cingulate, and angular gyrus, using voxel-based morphometry (VBM), to investigate the association between bone loss and AD. Methods: A cohort of 149 consecutive elderly participants who complained of memory disturbance underwent high-resolution structural brain magnetic resonance imaging (MRI) and dual-energy X-ray absorptiometry (DXA). We used SPM12 software to conduct a voxel-based multiple regression analysis to examine the association between femoral neck BMD values and regional gray matter volume (rGMV) on structural T1-weighted MRI. Results: After adjusting for subject age, gender, total brain volume (TBV), and mini-mental state examination (MMSE) scores, the multiple regression analysis showed significant correlations between BMD loss and rGMV decline in the left precuneus, which is an important neural network hub vulnerable to AD. Conclusion: These data suggest that the bone and brain communicate with each other, as in "bone-brain crosstalk," and that control of BMD factors could contribute to cognitive function and help prevent AD.
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Accelerated bone loss is closely associated with Alzheimer's disease (AD), but the relationship between bone mineral density (BMD) and imaging markers of neurodegeneration remains uncertain. We examined the effect of low bone mass (osteopenia) on regional cerebral blood flow (rCBF) in patients with AD (n = 19) and non-demented aging (n = 12). We enrolled 31 female outpatients diagnosed with osteopenia (age ≥ 65 years) who had both a single-photon emission computed tomography brain scan and dual-energy X-ray absorptiometry bone scan taken at their initial investigation. We analyzed the relationship between osteopenia (-2.5 < T-score < -1) and rCBF in 62 cortical areas measured using the stereotactic extraction estimation analysis on single-photon emission computed tomography (SPECT) (mean Z-scores). We found that the mean Z-scores of 14 cerebral subregions, most of which are often affected early in AD, were significantly lower in the AD group than the non-demented group (P < .001). The age-stratified multivariate regression analysis showed that the decreased rCBF in the left posterior cingulate cortex (PCC) was an independent predictor of osteopenia (r = -0.395; P = .005). BMD and rCBF in the left PCC were significantly correlated in the overall population (r = -0.54; P = .001), as well as the AD group (r = -0.514; P = .02). These imaging data suggest that osteopenia may contribute to neurodegeneration of a brain network hub associated with AD.
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Doença de Alzheimer/diagnóstico por imagem , Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Giro do Cíngulo/irrigação sanguínea , Giro do Cíngulo/diagnóstico por imagem , Absorciometria de Fóton/tendências , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/fisiopatologia , Doenças Ósseas Metabólicas/epidemiologia , Doenças Ósseas Metabólicas/fisiopatologia , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/tendências , Estudos RetrospectivosRESUMO
BACKGROUND The diagnosis of early non-convulsant status epilepticus (NCSE) can be challenging and can overlap with other critical conditions. Two patients with Alzheimer's disease are reported with clinically suspected NCSE presenting in the emergency setting who were diagnosed using arterial spin-labeling magnetic resonance imaging (ASL-MRI) sequences. CASE REPORT In Case 1, a 69-year-old woman with mild Alzheimer's disease and diabetes presented with acute worsening of cognitive status and fluctuating level of consciousness. In Case 2, a 70-year-old man with mild cognitive impairment due to Alzheimer's disease and hypertension presented with acute loss of consciousness and left hemiparesis, without evidence of hypoglycemia or a hypertensive crisis. In both cases, ASL-MRI perfusion images showed focal cerebral hyperperfusion in the posterior cingulate and parietal associative cortex, which involved neurodegenerative areas associated with epilepsy in early Alzheimer's disease. In both cases, the patients developed generalized tonic-clonic epileptic seizures that lasted for 5 minutes or more, which indicated the emergence of status epilepticus that developed from the initial presentation of NCSE. In both cases, electroencephalogram (EEG) findings confirmed that the seizures were controlled by intravenous administration of antiepileptic drugs. Both patients discharged home from the hospital without recurrence of seizures, between 10-12 days after the onset of symptoms. CONCLUSIONS These two cases have demonstrated that ASL-MRI is feasible as an emergency diagnostic tool in clinically suspected NCSE in patients with Alzheimer's disease.
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Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico por imagem , Estado Epiléptico/diagnóstico por imagem , Estado Epiléptico/etiologia , Idoso , Anticonvulsivantes/uso terapêutico , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Marcadores de Spin , Estado Epiléptico/tratamento farmacológicoRESUMO
BACKGROUND Osteoporosis is a major global public health problem in the current aging era. Osteoporosis is often diagnosed only after patients have a fracture that causes a severe decline in ability to perform activities of daily life. Although the current criterion standard for diagnosing osteoporosis is dual-energy X-ray absorptiometry (DXA), this modality remains less prevalent among general practitioners in geriatric medicine. The aim of this study was to determine the diagnostic utility of visual inspection of lumbar radiography in detecting bone mineral density (BMD) decline. MATERIAL AND METHODS We retrospectively reviewed medical data of 78 patients who underwent both lateral lumbar radiography and DXA. Board-certified radiologists determined the clinical grade of each patient's condition according to the semiquantitative (SQ) method of lumbar fracture assessment. We compared the grades and young adult means of BMD in the lumbar spine and hips as measured using DXA. RESULTS BMD of the femoral neck was significantly lower in patients with severe osteoporosis (grades 2 and 3 as classified using the SQ method) than in those with mild osteoporosis (grades 0 and 1; P<0.05). A receiver operating characteristic curve analysis showed that the SQ method can help predict the decrease in BMD (young adult mean score of <70%) in the femoral neck with moderate accuracy (sensitivity, 0.621; specificity, 0.829; area under the curve, 0.742). CONCLUSIONS These results suggest that lateral lumbar radiography can provide useful information about bone mineral status and can serve as a tool for osteoporosis screening by general practitioners.
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Vértebras Lombares/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Osteoporose/diagnóstico , Radiografia/métodos , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Feminino , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Análise de Regressão , Adulto JovemRESUMO
BACKGROUND Convincing evidence regarding gait and balance function in elderly women with low bone mineral density (BMD) and/or osteoporosis is limited. In the present study, we aimed to compare the gait characteristics in elderly women with and without low BMD and to analyze plausible parameter(s) for predicting low BMD. MATERIAL AND METHODS We retrospectively analyzed prospectively collected data of 26 consecutive postmenopausal women aged >65 years who were admitted to our geriatric outpatient service. They were assigned to 2 groups, with (n=14) and without (n=12) low BMD based on T-score (0.05). Receiver operating characteristic curve analysis demonstrated that LI can predict low BMD in the femur neck with moderate accuracy (area under the curve=0.75, 95% confidence interval 0.55-0.95; P=0.031). The optimal cut-off value was 17%, with 67% specificity and 86% sensitivity. CONCLUSIONS These results suggest that elderly women with low BMD may walk with asymmetrical trunk movement, but they are able to generate gait patterns similar to healthy peers. The LI may provide valuable quantitative information for preventing fractures in subjects with osteoporosis.
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Acelerometria/instrumentação , Doenças Ósseas Metabólicas/fisiopatologia , Marcha/fisiologia , Idoso , Feminino , Humanos , Projetos Piloto , Curva ROC , Velocidade de CaminhadaRESUMO
CASE: Non-convulsive status epilepticus (NCSE) is among the differential diagnoses of decreased consciousness, but often presents a diagnostic challenge. A 65-year-old woman was admitted to our emergency department with bradylalia. No abnormal finding was detected by computed tomography or magnetic resonance imaging. Subsequently, acquired arterial spin-labeling images showed hyperperfusion in the right hemisphere. OUTCOME: After the examination, the patient began experiencing left hemifacial seizures, which were relieved by diazepam; however, she was still agitated. Ictal confusion due to NCSE was suspected. Electroencephalography revealed periodic, generalized epileptiform activities with brief seizures of facial muscles by intermittent photic stimulation. Another supportive case of NCSE detected by arterial spin-labeling from a 56-year-old right-handed man has also been presented. CONCLUSION: Arterial spin-labeling magnetic resonance perfusion imaging provides valuable information regarding cerebral perfusion status in NCSE patients in emergency/acute settings.
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Early brain injury and related cardiac consequences play a key role in the devastating outcomes after subarachnoid hemorrhage (SAH). We reported that rapamycin exerts neuroprotection against cortical hypoxia early after SAH, but its mechanism is poorly understood. This in vivo study aimed to determine the potential role of the transcription factor STAT3 in the rapamycin-mediated neuroprotection in a mouse model of SAH. Forty C57BL/6 N mice were treated with an intracerebroventricular injection of rapamycin or vehicle (control) given after SAH induction by a filament perforation method, with or without STAT3 (Stattic) or ERK (PD98059) inhibitor pretreatment. Cerebral blood flow signals (%vascularity), brain tissue oxygen saturation (SbtO2), and cardiac output (CO) were analyzed using an ultrasound/photoacoustic imaging system. Clinically relevant neurocardiac depression was notable in severe SAH mice. Rapamycin improved %vascularity, SbtO2, and CO on day 1 after SAH onset. The beneficial effects of rapamycin on cerebral blood flow and oxygenation persisted until day 3, resulting in a significant reduction in post-SAH new cerebral infarctions and survival, as well as improved neurological functions, compared to the control group. All of the effects were attenuated by pretreatment with Stattic or PD98059. These data suggest that ERK and JAK/STAT3 pathways play an important role in the neurocardiac protection by rapamycin after SAH. We propose that rapamycin is a novel pharmacological strategy to target STAT3 activation, with a possible crosstalk through the ERK pathway, for the treatment of post-SAH early brain injury.
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Arritmias Cardíacas/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Sirolimo/metabolismo , Animais , Encéfalo/metabolismo , Lesões Encefálicas/tratamento farmacológico , Circulação Cerebrovascular/efeitos dos fármacos , Modelos Animais de Doenças , Janus Quinases , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Fator de Transcrição STAT3 , Sirolimo/farmacologia , Hemorragia Subaracnóidea/induzido quimicamente , Hemorragia Subaracnóidea/tratamento farmacológicoRESUMO
We aimed to evaluate the feasibility of a non-invasive method of cerebral blood flow (CBF) measurement using high-frequency power Doppler ultrasound imaging in a mouse model of subarachnoid haemorrhage (SAH). The 3-dimensionally (3D) reconstructed blood flow signals (%vascularity) within the brain volume of the middle cerebral artery territory correlated well with reference parameters, baseline carotid artery blood flow (r2 = 0.52, P < 0.0001) and normalized CBF changes (r2 = 0.74 P < 0.0001). These data suggest that the 3D power Doppler analysis may have the potential for reflecting real-time CBF changes during the acute phase of experimental SAH, which may be applicable to preclinical studies on early brain injury.
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Circulação Cerebrovascular , Imageamento Tridimensional , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/fisiopatologia , Ultrassonografia Doppler , Animais , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiopatologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: Fluid therapy guided by cardiac output measurements is of particular importance for adequate cerebral perfusion and oxygenation in neurosurgical patients. We examined the usefulness of a noninvasive electrical velocimetry (EV) device based on the thoracic bioimpedance method for perioperative hemodynamic monitoring in patients after aneurysmal subarachnoid hemorrhage. PATIENTS AND METHODS: In total, 18 patients who underwent surgical clipping or endovascular coiling for ruptured aneurysms were examined prospectively. Simultaneous cardiac index (CI) measurements obtained with EV (CIEV) and reference transpulmonary thermodilution (CITPTD) were compared. A total of 223 pairs of data were collected. RESULTS: A significant correlation was found between CIEV and CITPTD (r=0.86; P<0.001). Bland and Altman analysis revealed a bias between CIEV and CITPTD of -0.06 L/min/m, with limits of agreement of ±1.14 L/min/m and a percentage error of 33%. Although the percentage error for overall data was higher than the acceptable limit of 30%, subgroup analysis during the postoperative phase showed better agreement (23% vs. 42% during the intraprocedure phase). Four-quadrant plot and polar plot analyses showed fair-to-poor trending abilities (concordance rate of 90% to 91%, angular bias of +17 degrees, radial limits of agreement between ±37 and ±40 degrees, and polar concordance rate of 72% to 75%), including the subgroup analysis. CONCLUSIONS: Absolute CI values obtained from EV and TPTD are not interchangeable with TPTD for perioperative use in subarachnoid hemorrhage patients. However, considering the moderate levels of agreement with marginal trending ability during the early postoperative phase, this user-friendly device can provide an attractive monitoring option during neurocritical care.
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Débito Cardíaco , Procedimentos Endovasculares/métodos , Monitorização Intraoperatória/métodos , Período Perioperatório , Reologia/métodos , Hemorragia Subaracnóidea/cirurgia , Idoso , Ruptura Aórtica/fisiopatologia , Ruptura Aórtica/cirurgia , Impedância Elétrica , Feminino , Hidratação , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/instrumentação , Reologia/instrumentação , Hemorragia Subaracnóidea/fisiopatologia , TermodiluiçãoRESUMO
BACKGROUND The fornix is a white matter tract bundle that acts as the major output of the hippocampus and is an important component of the Papez circuit. We present an instructive imaging case of sudden onset of persistent amnesia due to selective ischemic damage of the anterior fornix. CASE REPORT A 54-year-old Japanese male came to our attention for a sudden onset of retrograde amnesia, associated with severe anterograde amnesia. The brain magnetic resonance imaging demonstrated a bright diffusion restriction, which was associated with swollen fornices bilaterally. His symptoms gradually improved, but episodic memory impairment still persisted after 1 month. The coronal T1-weighted MPRAGE (magnetization-prepared rapid acquisition with gradient echo) sequence clearly showed disruption of the left anterior fornix. Diffusion tensor tracking showed decrease in the density of entire fiber tracts on the Papez circuit as well as location of the left fornix. CONCLUSIONS When dealing with sudden, persistent amnesia associated with small fornix infarction, it is prudent to consider the possibility of tract damage along with limbic system damage using MPRAGE sequence.
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Amnésia Retrógrada/etiologia , Infarto Cerebral/complicações , Imagem Ecoplanar/métodos , Fórnice/patologia , Sistema Límbico/fisiopatologia , Neuroimagem/métodos , Amnésia Retrógrada/diagnóstico , Infarto Cerebral/diagnóstico por imagem , Fórnice/diagnóstico por imagem , Humanos , Sistema Límbico/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Prognóstico , Medição de RiscoRESUMO
BACKGROUND Fluid resuscitation is a cornerstone of minimizing morbidity and mortality in critically ill patients, but the techniques for predicting fluid responsiveness is still a matter of debate. In this study, we aimed to evaluate the utility of noninvasive stroke volume variation (SVV), pulse pressure variation (PPV), and systolic pressure variation (SPV) as a dynamic predictor for assessing fluid responsiveness during different ventilation modes in anaesthetized, intubated dogs recovering from cardiac surgery. MATERIAL AND METHODS Thirty-six adult Beagle dogs undergoing experimental surgery for isolated right ventricular failure were monitored for SVV, PPV, and SPV simultaneously using electrical velocimetry device. The relationships between each indicator and SVI before and after volume loading were compared in 3 ventilatory modes: assist control (A/C), synchronized intermittent mandatory ventilation (SIMV), and continuous positive airway pressure (CPAP). Responders were defined as those whose stroke volume index increased by ≥10%. RESULTS In all of the indices, the baseline values were greater in responders than in nonresponders (P<0.01) under A/C and SIMV. Receiver operating curve analysis confirmed the best predictive value during A/C [area under the curve (AUC): SVV, 0.90; PPV, 0.88; SPV, 0.85; P<0.05] followed by SIMV (AUC: SVV, 0.86; PPV, 0.83; CPAP, 0.80; P<0.05), with their sensitivities and specificities of ≥7 5%. By contrast, no statistically significance detected in any parameter during CPAP (AUC: SVV, 0.71; PPV, 0.66; CPAP, 0.65; P>0.05). CONCLUSIONS SVV, PPV, and SVV are all useful to predict cardiac response to fluid loading in dogs during A/C and SIMV, while their reliabilities during CPAP are poor.
Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Respiração Artificial/métodos , Animais , Pressão Sanguínea , Cães , Hidratação/métodos , Masculino , Curva ROC , Reologia , Sensibilidade e Especificidade , Volume Sistólico/fisiologiaRESUMO
We evaluated the utility of noninvasive stroke volume variation (SVV) as a functional haemodynamic predictor for fluid responsiveness under different ventilation modes [assist control (A/C), synchronized intermittent mandatory ventilation (SIMV), and continuous positive airway pressure (CPAP)] in 45 anaesthetized dogs, using an electrical velocimetry device. Receiver operating curve analysis confirmed the best predictive value during SVVA/C (12.5% of cut-off value; 75% sensitivity and 86% specificity) followed by SVVSIMV (13.5% of cut-off value; 75% sensitivity and 75% specificity), while no statistically significance detected during SVVCPAP (P > .05). These data suggest that SVV is useful for the prediction of fluid responsiveness in laboratory dogs during A/C and SIMV, while its reliability during CPAP is poor. This article is protected by copyright. All rights reserved.