Evolution of a Radially Aligned Microstructure in Boron-Doped Li[Ni0.95Co0.04Al0.01]O2 Cathode Particles.

Boron (B) (1.5 mol %) is introduced into Li[Ni0.95Co0.04Al0.01]O2 (NCA95) to create a radially oriented microstructure with a strong crystallographic texture. The cathode microstructure allows dissipation of the abrupt lattice strain near the charge end and improves the cycling stability of the NCA95 cathode (88% capacity retention after 100 cycles at 0.5 C). Transmission electron microscopy (TEM) analysis of the B-doped NCA95 cathode during lithiation reveals that the highly oriented microstructure is provided by a hydroxide precursor. Boron prevents random agglomeration of the primary particles and keeps them elongated through (003) faceting. The selected-area electron diffraction analysis shows that the structure of the lithiated oxide undergoes subtle structural changes even after the crystal structure is fully converted from P3̅m1 to R3̅m at 600 °C. Li+/Ni2+ intermixing is prevalent due to the slow oxidation of Ni2+ to Ni3+. Li+ and Ni2+ do not randomly occupy the Ni and Li layers; instead, these ions occupy their sites in an ordered pattern, forming a superlattice. The superlattice gradually disappears as the lithiation temperature is increased. One peculiar structural feature observed during lithiation is the prevalence of twin defects that preexist in the hydroxide precursor as growth twins. The twin defects, which could serve as nucleation sites for intraparticle cracks, also gradually anneal out during lithiation. TEM analysis substantiates the importance of the hydroxide precursor microstructure in a coprecipitation process and provides a basis for choosing the appropriate lithiation temperature and soaking time to obtain the desired cathode structure and primary particle morphology.

Relationship between clinical phenotypes and cognitive impairment in Parkinson's disease (PD).

Most patients with idiopathic PD (IPD) show variable degrees of cognitive decline. The purpose of this study was to evaluate the relationship between the predominant motor symptom at the time of disease onset and the level of cognitive function in patients with IPD. A total of 159 patients with IPD were enrolled in this study. The patients' initial motor symptoms were classified into three types: tremor-dominant (TD), bradykinesia and rigidity-dominant (BRD), gait and postural instability-dominant (GPD). Disease severity was rated according to the Hoehn-Yahr classification (H&Y stage). Overall cognitive status was evaluated using the Korean versions of the Mini-Mental State Examination (K-MMSE) and the Modified Mini-Mental State (3MS) tests. The GPD group showed the lowest scores of the K-MMSE/3MS, and the patients with TD showed the best performance in the cognitive analysis (p<0.05). The patients who were older at disease onset showed worse cognitive performance than those the patients who were younger at disease onset (p<0.05). There was no difference in cognitive status according to H&Y stages. The accurate classification of initial motor symptoms and the detailed history, including the exact onset age of IPD, may allow us to predict cognitive decline in IPD.

Relationship between brachial-ankle pulse wave velocity and cognitive function in an elderly community-dwelling population with metabolic syndrome.

Arterial stiffness (AS) and metabolic syndrome (MS) may correlate with poor cognitive function in elderly people. However, few studies have evaluated this relationship in a healthy, community-dwelling elderly population. Our aim was to evaluate a relationship between the AS measured by pulse wave velocity (PWV) and cognitive function and to know whether the relationship is influenced by the presence of MS. Our study population was community-dwelling healthy people in Geumsan province, Republic of Korea. A total of 370 participants without a history of cerebrovascular disease were evaluated with the Korean version of the mini-mental state examination (K-MMSE) and have measured the brachial-ankle PWV (baPWV). Correlation between baPWV and cognitive status and effect of MS were measured. Negative correlation between PWV and cognitive function was found in the older subjects (> or = 60 years of age) with MS (r=-0.38; p<0.05). In the receiver operating characteristic (ROC) curve, the cut-off score was 1800.8 cm/s with 67% sensitivity and 78% specificity. Aging (older than 60 years) and the presence of MS may affect synergistically cognitive decline in the elderly population. The baPWV can be a useful predictor for cognitive decline in elderly healthy community-dwelling population with MS.

Relation between the clock drawing test (CDT) and structural changes of brain in dementia.

The CDT is a useful screening instrument for assessing cognition. The aim of this study is to identify which structural change of the brain is related with the CDT performance. Eighty-four patients with memory impairment were enrolled. The Korean versions of the mini-mental state examination (K-MMSE) and the modified mini-mental state (3MS) test, and the Seoul Neuropsychological Screening Battery (SNSB) were given to every subject. Four CDT scoring methods were used. The cerebral white matter hyperintensity (WMH), cortical atrophy (CA), ventricular enlargement (VE), and medial temporal lobe atrophy (MTA) were rated by two neurologists who were kept "blind" to the clinical information. The cognitive and executive functions were significantly correlated with the CDT performance. The degree of WMH and MTA showed an inverse relation with the CDT performance. The periventricular WMH (PVH) contributed more to impairment of CDT, than that of the deep WMH (DWMH). This study suggests that a combination of executive dysfunction via the frontal-subcortical disruption due to the PVH and memory impairment due to the MTA might be responsible for further worsening on the CDT.

Successful anticoagulation for bilateral central retinal vein occlusions accompanied by cerebral venous thrombosis.

BACKGROUND: Concurrent development of retinal venous drainage and cerebral venous thrombosis has not been reported. Case Description We describe a 23-year-old man with bilateral central retinal vein occlusions and cerebral venous thrombosis. Initially observed bilateral hemorrhagic retinopathy and thrombus in the right transverse sinus of the patient began to resolve after 2 weeks of low-molecular-weight heparin. Hemorrhagic retinopathy progressively improved to previous visual acuity and the right lateral sinus remained patent by maintenance of anticoagulation with warfarin. CONCLUSION: The present case shows effectiveness of low-molecular-weight heparin for the initial management of hemorrhagic retinopathy of central retinal vein occlusion combined with cerebral venous thrombosis.

Classification and Serial Evolution of PLEDs.

BACKGROUND AND PURPOSE: Periodic lateralized epileptiform discharges (PLEDs) are defined as spikes or sharp waves occurring at an approximately regular interval. PLEDs are subdivided into PLEDs proper and PLEDs plus in Reiher's classification, but since this does not sufficiently reflect the pleomorphism of PLEDs, we propose a new subclassification scheme of PLEDs, and discuss the relationship between them and clinical prognoses. METHODS: Thirty-seven patients who had at least two available EEGs were included in this study. Each patient had structural brain lesions identified in brain CT/MRI: 237 EEGs from 37 patients were reviewed and the patterns of PLEDs were classified by electroencephalographic characteristics based on Reiher's classification. PLEDs proper of class 3 were subclassified into four categories: (1) simple, (2) benign, (3) vigorous, and (4) suppressed. RESULTS: Most of the PLEDs that started with the vigorous or suppressed pattern of class 3 evolved into the simple or benign pattern of class 3 and subsequently changed into class 1 or class 2, finally intermingling with the neighboring background waves. PLEDs that started with the benign or simple pattern of class 3 rapidly changed into class 1 or 2. Patients showing the benign or simple pattern of class 3 exhibited a better clinical prognosis. CONCLUSIONS: PLEDs have five distinctive classes, and over time they evolve from malignant PLEDs plus to benign PLEDs proper before finally disappearing. It appears that those of class 3 have more diverse patterns, with the vigorous and suppressed patterns being the more malignant forms of PLEDs in this class.