[Overview and assessment of cognitive function in interpreting postoperative cognitive dysfunction].

The most important point for evaluation of the post-operative cognitive dysfunction is that we understand "cognitive function". First we described the definition of the "cognitive function" and second, outlined each function (dysfunction) and introduced the main assessment methods from the view point of neuropsychology. Cognitive function (dysfunction) described in this paper includes consciousness (confusional state, disturbance of consciousness), generalized attention (disorder of generalized attention), memory (amnesia), orientation (disorientation), executive function (dysexecutive syndrome), social cognition (social cognitive impairment), language (aphasia), cognition (agnosia), behavior (apraxia), directed attention (unilateral spatial neglect), and construction (constructional disorder).

Neuropsychological differentiation between Alzheimer's disease and dementia with Lewy bodies in a memory clinic.

OBJECTIVE: The aim of this study was to identify a useful neuropsychological instrument for making a differential clinical diagnosis between Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). METHODS: We examined 402 AD and 38 DLB patients with neuropsychological tests that covered general cognition, frontal lobe cognitive function, non-verbal abstract reasoning, working memory and attention, and verbal memory. Discriminant analysis using a stepwise method was performed to identify the measures best able to discriminate between AD and DLB. RESULTS: The AD patients performed significantly worse than the DLB patients on orientation to time, delayed recall subtests on the Mini-Mental State Examination, and logical memory subtests 1 and 2 of the Revised Wechsler Memory Scale. The DLB patients performed significantly worse than the AD patients on the attention, repetition, and pentagon copying subtests of the Mini-Mental State Examination, the constructional praxis subtests of the Alzheimer's Disease Assessment Scale-cognitive component-Japanese version, the Frontal Assessment Battery total score, Raven's Coloured Progressive Matrices (RCPM) sets A, AB, and B, and backward digit span. Discriminant analyses between AD and DLB established the key variables as Logical Memory 1, Logical Memory 2, backward digit span, RCPM, and delayed recall on the Mini-Mental State Examination. We inferred the AD-DLB discriminant index from the following discriminant analyses: AD-DLB discriminant index = (Backward digit span score + RCPM set B score) - (Logical Memory 1 score + Logical Memory 2 score), which offered a highly favourable value for diagnostic utility. CONCLUSIONS: The AD-DLB discriminant index, consisting of backward digit span, RCPM set B, and logical memory 1 and 2, is useful to differentiate between AD and DLB.

Clinical psychological tests useful for differentiating depressive state with Alzheimer's disease from major depression of the elderly.

BACKGROUND: A depressive state with Alzheimer's disease (AD) is difficult to differentiate from major depression (MD) in many cases. The purpose of this study was to identify differences between the two disorders using a battery of clinically available psychological tests. METHODS: We evaluated depression and apathy using the Geriatric Depression Scale consisting of 30 items (GDS30) and Apathy Scale in 38 patients with AD and 31 with MD who were diagnosed based on clinical symptoms and radiological findings. In addition, the Cornel Medical Index (CMI) was employed to compare the psychological features of the two disorders. RESULTS: In AD patients, the Apathy Scale score was greater than the GDS30 score, suggesting a strong tendency toward apathy. There was a significant difference in the GDS30/Apathy Scale score ratio between the two groups (P < 0.05, OR: 3.11). When examining the downstream mental items of the CMI, the values of tension-category parameters were significantly greater in AD patients, whereas those of depression-category parameters were significantly higher in MD patients. In individual patients, we compared the scores for the two categories, and there was a marked difference (P < 0.001, OR: 10.6). CONCLUSION: These results suggest that the GDS30, Apathy Scale, and CMI are useful for differentiating MD from AD and evaluating their psychological features.

Endogenous α2A-Adrenoceptor-Operated Sympathoadrenergic Tones Attenuate Insulin Secretion via cAMP/TRPM2 Signaling.

In pancreatic ß-cells, pharmacological concentrations of catecholamines, including adrenaline, have been used to inhibit insulin release and explore the multiple mechanisms involved. However, the significance of these signaling pathways for physiological adrenergic functions in ß-cells is largely unknown. In the process of glucose-induced insulin secretion, opening of background current through nonselective cation channels (NSCCs) might facilitate membrane depolarization by closure of the ATP-sensitive K+ channels. Here, we examined whether physiological insulinostatic adrenaline action is mediated via the transient receptor potential melastatin 2 (TRPM2) channel, a type of NSCC, in ß-cells. Results showed that physiological concentrations of adrenaline strongly suppressed glucose-induced and incretin-potentiated cAMP production and insulin secretion and inhibited NSCCs current and membrane excitability via the α2A-adrenoceptor in wild-type mice; however, insulin secretion was not attenuated in TRPM2-knockout (KO) mice. Administration of yohimbine, an α2-adrenoceptor antagonist, failed to affect glucose tolerance in TRPM2-KO mice, in contrast to an improved glucose tolerance in wild-type mice receiving the antagonist. The current study demonstrated that a physiological concentration of adrenaline attenuates insulin release via coupling of α2A-adrenoceptor to cAMP/TRPM2 signaling, thereby providing a potential therapeutic tool to treat patients with type 2 diabetes.

Proper name anomia after left temporal subcortical hemorrhage.

We report here a patient with proper name anomia following subcortical hemorrhage in the left superior temporal gyrus. Despite the preserved ability to retrieve common names, the patient could not retrieve the names of people, countries, or racehorses, which he could recognize quite well. Semantic knowledge regarding people, countries, and racehorses was also preserved. In addition. the finding that phonological cueing was effective with preservation of the ability to point to photos corresponding to their names suggested that the lexicon of proper names was preserved in this patient. Thus, the output lexicon appeared to be partially disconnected from semantic knowledge. This rare and limited lesion suggested that the superior temporal gyrus plays an important role in connecting semantic knowledge and the output lexicon.

The ß-cell GHSR and downstream cAMP/TRPM2 signaling account for insulinostatic and glycemic effects of ghrelin.

Gastric hormone ghrelin regulates insulin secretion, as well as growth hormone release, feeding behavior and adiposity. Ghrelin is known to exert its biological actions by interacting with the growth hormone secretagogue-receptor (GHSR) coupled to G(q/11)-protein signaling. By contrast, ghrelin acts on pancreatic islet ß-cells via Gi-protein-mediated signaling. These observations raise a question whether the ghrelin action on islet ß-cells involves atypical GHSR and/or distinct signal transduction. Furthermore, the role of the ß-cell GHSR in the systemic glycemic effect of ghrelin still remains to be defined. To address these issues, the present study employed the global GHSR-null mice and those re-expressing GHSR selectively in ß-cells. We here report that ghrelin attenuates glucose-induced insulin release via direct interaction with ordinary GHSR that is uniquely coupled to novel cAMP/TRPM2 signaling in ß-cells, and that this ß-cell GHSR with unique insulinostatic signaling largely accounts for the systemic effects of ghrelin on circulating glucose and insulin levels. The novel ß-cell specific GHSR-cAMP/TRPM2 signaling provides a potential therapeutic target for the treatment of type 2 diabetes.

[Evaluation of SMBG values using various instruments and clinical significance of forearm SMBG measurement].

Whole blood or plasma glucose values were compared between those measured using various instruments for SMBG and automated analyses in samples (antecubital vein) from 20 approximately 70 years old obtained at cookie tests. A good correlation between values in whole blood SMBG and plasma automated analyses values greater than r = 0.94 was observed for instruments A, C, F, and H, and the per cent difference from the automated values was less than 5% for A, B, E and H. Per cent difference of SMBG values by I was -16% in whole blood and -9% in plasma, suggesting the possibility of measuring real values in whole blood. With plasma, a good correlation greater than r = 0.95 was noted for A, C, F and K, and the per cent difference less than 10% was noted for C, E, F and I. A relatively good correlation (r: 0.63 approximately 0.90) between forearm SMBG value and plasma automated values was noted with the % difference of the mean less than 11%. During cookie test, there is no significant difference between forearm SMBG values and antecubital plasma automated values. Values at finger tips are significantly greater by 5 approximately 20% over automated plasma values. In conclusion, whole blood values by most of the SMBG instruments are well correlated with plasma automated values, although some disagreement was noted. Values at forearm are not different from plasma val ues of antecubital vein, while at finger tip SMBG values showed higher levels. The measurement at forearm is therefore recommended, and in addition the pain is less.

[Normative data on tests for frontal lobe functions: Trail Making Test, Verbal fluency, Wisconsin Card Sorting Test (Keio version)].

Trail Making Test (TMT Part A, B), Verbal fluency test (phonemic, semantic) and Wisconsin Card Sorting Test (Keio version : KWCST) are useful to evaluate frontal lobe functions and are commonly used in clinical settings. However, few normative data for aged Japanese have been reported. We collected normative data on these tests in elderly population, and examined the effects of age and education on the performance of these tests. Seventy-six healthy adults, aged 45 to 74 years, participated in this study. Subjects were classified into three groups by age (45-54, 55-64, 65-74). Fifty-five subjects repeated the same tests after 6 months to examine the test-retest reliability. Performance of the TMT Part A was correlated with age (r= 0.530) and that of Part B was correlated with age (r=0.500) and education (r=-0.340). Performance on both phonemic and semantic fluency was correlated with education (phonemic: r=0.357, semantic: r=0.279). Number of Categories Achieved (CA) of KWCST was correlated with education (r=0.376). The test-retest reliability of all these tests except for semantic verbal fluency and difficulty maintaining set (DMS) of KWCST was good enough for longitudinal studies.

Preserved ability to recognize keywords related to remote events in the absence of retrieval of relevant knowledge: a case of postencephalitic amnesia.

We describe a case of severe anterograde and retrograde amnesia resulting from herpes simplex encephalitis. Magnetic resonance imaging revealed pathological changes in the bilateral hippocampi, parahippocampal gyri, fusiform gyri, medial temporal poles, posterior part of the cingulate gyri, and insula. The patient showed severe amnesia for autobiographical episodic memory in relation to events that had occurred throughout her life, but temporally graded amnesia for autobiographical semantic memory, and severe amnesia without a temporal gradient for public events and famous people. However, using a multiple-choice method, she showed a high level of accuracy when choosing keywords related to public or personal events, although this did not prompt her recollection of the events. An important indication of these results is that, even with severe retrograde amnesia, memories of past events are not completely lost. We propose that an event may be stored in a fragmented form, consisting of many components, and that normal recall of an event may require recombination or reconstruction of these components.

The role of the basal forebrain in episodic memory retrieval: a positron emission tomography study.

Human lesion data indicate that the basal forebrain or orbitofrontal cortex, or both, as well as medial temporal and diencephalic structures, is important for normal memory and that its disruption causes the pure amnesic syndrome, in which episodic memory is grossly impaired while other kinds of memory remain preserved. Among these critical areas, functional imaging studies have so far failed to detect activation of the basal forebrain, although activation in the nearby orbitofrontal cortex has been reported during episodic memory retrieval. We employed positron emission tomography to elucidate the neural basis of episodic memory recall utilizing two types of time cues and successfully detected activity in the basal forebrain for the first time. Specifically, recall of previously memorized words from temporal cues was associated with activity in the basal forebrain, right middle frontal gyrus, right superior temporal gyrus, and posterior cingulate gyrus, whereas their recall from person cues was associated with activity in the left insula, right middle frontal gyrus, and posterior cingulate gyrus. Furthermore, percentage increases of regional blood flow in the basal forebrain were correlated with behavioral data of successful recall. Our results provide clear evidence that the human basal forebrain has a specific role in episodic memory recall, especially that from time-contextual information.