[A Case of Bacterial Meningitis in Which Occurrence of Ataxie Optique Led to Detection of a Small Subdural Abscess and Pialitis].

We report the case of a 69-year-old man with bacterial meningitis who presented with ataxie optique in the peripheral part of the left visual field in both hands. A detailed neurological examination with contrast-enhanced brain MRI in the early stage of the clinical course identified a small subdural abscess and pialitis in the right parietal area. A favorable outcome was obtained with antibiotic therapy alone. In a case with higher brain dysfunction of unknown cause in the clinical course of bacterial meningitis, a detailed neurological examination may be helpful to identify the causative site. (Received September 25, 2023; Accepted October 31, 2023; Published March 1, 2024).

Cascade process mediated by left hippocampus and left superior frontal gyrus affects relationship between aging and cognitive dysfunction.

BACKGROUND: Cognitive function declines with age and has been shown to be associated with atrophy in some brain regions, including the prefrontal cortex. However, the details of the relationship between aging and cognitive dysfunction are not well understood. METHODS: Across a wide range of ages (24- to 85-years-old), this research measured the gray matter volume of structural magnetic resonance imaging data in 39 participants, while some brain regions were set as mediator variables to assess the cascade process between aging and cognitive dysfunction in a path analysis. RESULTS: Path analysis showed that age affected the left hippocampus, thereby directly affecting the left superior frontal gyrus. Furthermore, the gyrus directly affected higher order flexibility and maintenance abilities calculated as in the Wisconsin card sorting test, and the two abilities affected the assessment of general cognitive function. CONCLUSION: Our finding suggests that a cascade process mediated by the left hippocampus and left superior frontal gyrus is involved in the relationship between aging and cognitive dysfunction.

Odors Associated With Autobiographical Memory Induce Visual Imagination of Emotional Scenes as Well as Orbitofrontal-Fusiform Activation.

Specific odors can induce memories of the past, especially those associated with autobiographical and episodic memory. Odors associated with autobiographical memories have been found to elicit stronger activation in the orbitofrontal cortex, hippocampus, and parahippocampus compared with odors not linked to personal memories. Here, we examined whether continuous odor stimuli associated with autobiographical memories could activate the above olfactory areas in older adults and speculated regarding whether this odor stimulation could have a protective effect against age-related cognitive decline. Specifically, we used functional magnetic resonance imaging to investigate the relationship between blood oxygen levels in olfactory regions and odor-induced subjective memory retrieval and emotions associated with autobiographical memory in older adults. In our group of healthy older adults, the tested odors induced autobiographical memories that were accompanied by increasing levels of retrieval and the feeling of being "brought back in time." The strength of the subjective feelings, including vividness of the memory and degree of comfort, impacted activation of the left fusiform gyrus and left posterior orbitofrontal cortex. Further, our path model suggested that the strength of memory retrieval and of the emotions induced by odor-evoked autobiographical memories directly influenced neural changes in the left fusiform gyrus, and impacted left posterior orbitofrontal cortex activation through the left fusiform response.

Volume of the right supramarginal gyrus is associated with a maintenance of emotion recognition ability.

Emotion recognition is known to change with age, but associations between the change and brain atrophy are not well understood. In the current study atrophied brain regions associated with emotion recognition were investigated in elderly and younger participants. Group comparison showed no difference in emotion recognition score, while the score was associated with years of education, not age. We measured the gray matter volume of 18 regions of interest including the bilateral precuneus, supramarginal gyrus, orbital gyrus, straight gyrus, superior temporal sulcus, inferior frontal gyrus, insular cortex, amygdala, and hippocampus, which have been associated with social function and emotion recognition. Brain reductions were observed in elderly group except left inferior frontal gyrus, left straight gyrus, right orbital gyrus, right inferior frontal gyrus, and right supramarginal gyrus. Path analysis was performed using the following variables: age, years of education, emotion recognition score, and the 5 regions that were not different between the groups. The analysis revealed that years of education were associated with volumes of the right orbital gyrus, right inferior frontal gyrus, and right supramarginal gyrus. Furthermore, the right supramarginal gyrus volume was associated with the emotion recognition score. These results suggest that the amount of education received contributes to maintain the right supramarginal gyrus volume, and indirectly affects emotion recognition ability.

Sex Differences in the Relationship of Serum Vitamin B1 and B12 to Dementia Among Memory Clinic Outpatients in Japan.

Dementia and cognitive impairment are considered to be one of the biggest social and medical problems. While there is a definite relationship between vitamin B and cognitive decline, this has yet to be fully assessed with regard to sex differences. Thus, the present study investigated the relationship of vitamin B1 or vitamin B12 with dementia in accordance with the sex in 188 patients who visited the Memory Clinic at Showa University Hospital in Japan from March 2016 to March 2019. Cognitive function was tested by the Japanese version of the Mini-Mental State Examination (MMSE) and Hasegawa Dementia Scale-Revised (HDS-R). Blood tests were performed to measure the vitamin levels. Logistic regression analysis was used to calculate the odds ratio (OR) for dementia and the 95% confidence interval (CI). Compared to the highest vitamin group (third tertile), the lowest vitamin group (first tertile) exhibited a significantly increased OR for dementia defined by MMSE for vitamin B1 (OR:3.73, 95% CI:1.52-9.16) and vitamin B12 (2.97, 1.22-7.28) among women. In contrast, vitamin levels were not significantly associated with dementia determined by MMSE in men. These findings were similar even when dementia was defined by HDS-R. The present study suggests that vitamin B1 plays a role in preventing development of dementia in women. Future longitudinal studies will need to be undertaken in order to examine whether decreasing vitamin levels occur before or after cognitive impairment, and whether maintaining a higher vitamin level can prevent a worsening of cognitive function and the development of dementia.

Entorhinal cortex and parahippocampus volume reductions impact olfactory decline in aged subjects.

INTRODUCTION: Pathological abnormalities first appear in the medial temporal regions including entorhinal cortex and parahippocampus in patients with Alzheimer's disease. Previous studies showed that olfactory decline in elderly subjects was associated with volume reductions in the left hippocampus and left parahippocampus without cognitive impairment. The aim of this study is to investigate the link between olfaction and volume reductions in the medial temporal regions including the parahippocampus, entorhinal cortex, and hippocampal subfields. METHOD: 27 elderly subjects and 27 young controls were measured olfaction acuity, cognitive function, and structural magnetic resonance imaging. Image processing and gray matter volumetric segmentation were performed with FreeSurfer. Volume data were analyzed with SPSS Statistics software. RESULTS: Interesting results of this study were that volume reduction in the entorhinal cortex was not directly linked with declining olfactory ability. Volume reduction in the left entorhinal cortex was correlated with volume reduction in the left parahippocampus and dentate gyrus. However, left parahippocampus volume reduction had the greatest impact on olfactory decline, and the entorhinal cortex and dentate gyrus might additionally contribute to olfactory decline. CONCLUSION: Our results indicate that olfactory decline may be directly reflected in the medial temporal regions as reduced parahippocampus volumes, rather than as morphological changes in the entorhinal cortex and hippocampus. The parahippocampus may play an important role in the association between memory retrieval and olfactory identification.

Takotsubo syndrome associated with autoimmune limbic encephalitis: a case report.

BACKGROUND: Central nervous system diseases are common triggers of Takotsubo syndrome. We herein report a rare case of Takotsubo syndrome associated with autoimmune limbic encephalitis. CASE PRESENTATION: A 68-year-old Japanese woman presented to our emergency room with disturbed consciousness. At admission, she showed hypoxemia. Left ventriculography showed akinesia in the middle part of the left ventricle and hyperkinesia in the apical and basal parts of the left ventricle, and the diagnosis of midventricular Takotsubo syndrome was established. However, after an improvement in disturbed consciousness and Takotsubo syndrome symptoms, her brother noticed something wrong with her behavior during his visit to the hospital. Subsequently, we consulted the neurology department 1 week after admission. Her brother revealed a history of abnormal behavior by the patient (such as mistaken entry in the wrong apartment in her building or in another person's car) a few days prior to the onset of disturbed consciousness, suggesting disorientation of place. Brain magnetic resonance imaging showed an increased signal in the medial aspect of the temporal lobes, which was most clearly observed on the fluid-attenuated inversion recovery sequence; additionally, a cerebrospinal fluid analysis revealed mild lymphocytic pleocytosis. Finally, we established a diagnosis of midventricular Takotsubo syndrome associated with autoimmune limbic encephalitis. CONCLUSIONS: It is presumed that the dysfunction of limbic system due to autonomic limbic encephalopathy is associated with exaggerated sympathetic stimulation. This likely resulted in Takotsubo syndrome in our patient.

Hippocampus and Parahippocampus Volume Reduction Associated With Impaired Olfactory Abilities in Subjects Without Evidence of Cognitive Decline.

The aim of this study was to investigate the relationship between olfactory recognition and morphological changes in olfactory brain regions including the amygdala, hippocampus, rectus, parahippocampus, orbitofrontal cortex, and medial frontal cortex in 27 elderly subjects and 27 younger healthy controls. The specific aim of the study was to determine which brain areas are associated with the initial decline of olfaction in elderly subjects, which occurs before the onset of dementia. All subjects underwent magnetic resonance imaging to measure anatomical brain volume and cortical thickness, and subjects were assessed using tests of olfactory acuity and cognitive function measured with the Montreal Cognitive Assessment. Overall brain volume reductions were observed in elderly subjects compared with young healthy controls, but only reduction in the volume of the left hippocampus was associated with decreased olfactory ability. The parahippocampus of elderly subjects was not different from that of controls; the extent of the reduction of parahippocampus volume varied among individuals, and reduction in this region was associated with olfactory decline. Similarly, parahippocampus thinning was associated with decreased olfactory function. The path analysis showed direct and indirect effects of hippocampus and parahippocampus volume on olfactory ability and that volume reductions in these areas were not associated with cognitive function. Parahippocampus volume reduction and thinning exhibited individual variation; this may be the first appearance of pathological changes and may lead to dysfunction in the connection of olfactory memory to the neocortex. Parahippocampus change may reflect the first sign of olfactory impairment prior to pathological changes in the hippocampus, amygdala and orbitofrontal cortex.

Heart Rate and Respiration Affect the Functional Connectivity of Default Mode Network in Resting-State Functional Magnetic Resonance Imaging.

A growing number of brain imaging studies show functional connectivity (FC) between regions during emotional and cognitive tasks in humans. However, emotions are accompanied by changes in physiological parameters such as heart rate and respiration. These changes may affect blood oxygen level-dependent signals, as well as connectivity between brain areas. This study aimed to clarify the effects of physiological noise on the connectivity between areas related to the default mode network using resting-state functional magnetic resonance imaging (rs-fMRI). Healthy adult volunteers (age range: 19-51 years, mean age: 26.9 ± 9.1 years, 8 males and 8 females) underwent rs-fMRI for 10 min using a clinical 3T scanner (MAGNETOM Trio A Tim System, Siemens) with simultaneously recorded respiration and cardiac output. Physiological noise signals were subsequently removed from the acquired fMRI data using the DRIFTER toolbox. Image processing and analysis of the FC between areas related to the default mode network were performed using DPARSF. Network-Based Statistic (NBS) analysis of the functional connectome of the DMN and DMN-related area was used to perform three groups of comparison: without physiological noise correction, with cardiac noise correction, and with cardiac and respiratory noise correction. NBS analysis identified 36 networks with significant differences in three conditions in FC matrices. Post hoc comparison showed no differences between the three conditions, indicating that all three had the same networks. Among the 36 networks, strength of FC of 8 networks was modified under physiological noise correction. Connectivity between left and right anterior medial frontal regions increased strength of connectivity. These areas are located on the medial cerebral hemisphere, close to the sagittal sinus and arteries in the cerebral hemispheres, suggesting that medial frontal areas may be sensitive to cardiac rhythm close to arteries. The other networks observed temporal regions and showed a decrease in their connectivity strength by removing physiological noise, indicating that physiological noise, especially respiration, may be sensitive to BOLD signal in the temporal regions during resting state. Temporal lobe was highly correlated with anxiety-related respiration changes (Masaoka and Homma, 2000), speech processing, and respiratory sensation. These factors may affect the rs-fMRI signaling sensitivity.

Prevalence of Smoking Among 4 Licensed Types of Nursing Personnel in Japan: An Epidemiological Study.

There is a high prevalence of smoking among nursing personnel, despite the fact that nursing is a health care profession. In Japan there are 4 types of licensed nursing professionals. However, the prevalence of smoking among different types of licensed personnel has not been clarified. We attempted to clarify the prevalence of smoking among the various types of licensed nursing personnel and the factors associated with it. Among the members of the Japanese Nursing Association, 6000 nurses were randomly selected. The participants were sent a questionnaire on smoking habits, personal characteristics, lifestyle habits, and employment status by mail. Current smokers accounted for 1.3% of public health nurses, 4.0% of midwives, 8.2% of registered nurses, and 16.3% of assistant nurses. The license type of nursing personnel was a factor significantly associated with current smoking.

The relationship between thyroid function and cerebral blood flow in mild cognitive impairment and Alzheimer's disease.

The thyroid hormones have been reported to be associated with cognitive decline and Alzheimer's disease. The relationship between thyroid function within the normal range and cerebral blood flow in Alzheimer's disease patients has been shown in a recent study. Mild cognitive impairment is often the first stage of Alzheimer's disease; thus, early diagnosis is important. The present study investigated the relationship between thyroid function and regional cerebral blood flow in patients with mild cognitive impairment and Alzheimer's disease. A total of 122 memory clinic outpatients who underwent thyroid function testing and single photon emission computed tomography were divided into mild cognitive impairment, Alzheimer's disease, and Normal groups. Regional cerebral blood flow was calculated using a three-dimensional stereotactic region of interest template in an automated cerebral perfusion single photon emission computed tomography analysis system. Multiple regression analysis adjusted for age and sex was conducted to examine the relationships between thyroid hormones and regional cerebral blood flow. Thyroid stimulating hormone was significantly associated with regional cerebral blood flow in the bilateral temporal, bilateral pericallosal, and bilateral hippocampal regions in the mild cognitive impairment group. In the Alzheimer's disease group, free triiodothyronine was significantly associated with regional cerebral blood flow in the bilateral parietal, right temporal, and bilateral pericallosal regions. The present study showed the association of thyroid stimulating hormone with regional cerebral blood flow in the mild cognitive impairment group and the association of free triiodothyronine with regional cerebral blood flow in the Alzheimer's disease group. These study findings could contribute to the early diagnosis of mild cognitive impairment at general memory clinics and the prevention of subsequent progression to Alzheimer's disease.

High serum high-density lipoprotein-cholesterol is associated with memory function and gyrification of insular and frontal opercular cortex in an elderly memory-clinic population.

The issue of whether serum lipid marker values are cognitively and neurologically significant for elderly individuals attending a memory clinic has been controversial. We investigated the associations of serum lipid markers with the memory function and cortical structure in 52 patients aged ≥75 years who had attended our memory clinic based on their subjective memory complaints. None had a history of medication for hyperlipidemia. The Wechsler Memory Scale-Revised (WMS-R) was administered to all patients for the assessment of their memory function. Serum low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDLC), and triglyceride (TG) were measured for each patient. Surface-based morphometry (SBM) was performed for the calculation of each patient's cortical thickness and gyrification index based on structural MRI data. Our analyses revealed that the serum HDLC level was positively and significantly correlated with the WMS-R subtests of visual paired associates I/II and logical memory I (p < 0.05). The serum TG level was negatively correlated with the logical memory I subtest. The SBM results showed positive correlations between the serum HDLC level and the gyrification indices of the bilateral insular and frontal opercular cortices, and those two gyrification indices were positively correlated with the logical memory I and visual paired associates I/II. These results suggest that in these elderly patients, a high serum HDLC level was associated with not only preserved memory function but also gyrification of the insular and frontal opercular cortex. We conclude that elderly individuals' serum lipid markers should be carefully assessed in memory clinic settings, because serum HDLC may be a biomarker for memory function and cortical structure.

Cerebrospinal fluid 5-HIAA concentrations correlate with cardiac uptake of 123I-MIBG during myocardial scintigraphy in drug naïve Parkinson's disease.

We examined the correlations between cerebrospinal fluid (CSF) concentrations of homovanillic acid (HVA) and 5-hydroxyindole acetic acid (5-HIAA) and imaging assessment scores, using 123I-Ioflupane SPECT and 123I-MIBG myocardial scintigraphy in 23 drug naïve PD patients. The CSF 5-HIAA concentration correlated with the H/M ratio of the delayed image (r = 0.458, p < 0.05) and the washout rate (r = - 0.642, p < 0.01) of 123I-MIBG myocardial scintigraphy. These correlations suggest some unclarified pathophysiological links between the central serotonergic and cardiac sympathetic systems.

Left Posterior Orbitofrontal Cortex Is Associated With Odor-Induced Autobiographical Memory: An fMRI Study.

Autobiographical odor memory (AM-odor) accompanied by a sense of realism of a specific memory elicits strong emotions. AM-odor differs from memory triggered by other sensory modalities, possibly because olfaction involves a unique sensory process. Here, we examined the orbitofrontal cortex (OFC), using functional magnetic resonance imaging (fMRI) to determine which OFC subregions are related to AM-odor. Both AM-odor and a control odor successively increased subjective ratings of comfortableness and pleasantness. Importantly, AM-odor also increased arousal levels and the vividness of memories, and was associated with a deep and slow breathing pattern. fMRI analysis indicated robust activation in the left posterior OFC (L-POFC). Connectivity between the POFC and whole brain regions was estimated using psychophysiological interaction analysis (PPI). We detected several trends in connectivity between L-POFC and bilateral precuneus, bilateral rostral dorsal anterior cingulate cortex (rdACC), and left parahippocampus, which will be useful for targeting our hypotheses for future investigations. The slow breathing observed in AM-odor was correlated with rdACC activation. Odor associated with emotionally significant autobiographical memories was accompanied by slow and deep breathing, possibly involving rdACC processing.

Antiangiogenic activity of flavonoids from Melia azedarach.

Three flavonoid glycosides, 1 (rutin: quercetin 3-O-rutinoside), 2 (kaempferol 3-O-robinobioside) and 3 (kaempferol 3-O-rutinoside) were isolated from the subcritical water extracts of Melia azedarach leaves. Strong antiangiogenic activity of these compounds was observed in the in vivo assay using the chorioallantoic membrane (CAM) from growing chick embryos.