Behavioral disturbances in geropsychiatric inpatients across dementia types.

The objective of this study was to compare differences in behavioral, psychiatric, and cognitive status among geropsychiatric inpatients with Alzheimer's, vascular, alcohol-induced, and mixed dementia. Participants included 150 patients with dementia consecutively admitted to an acute geropsychiatric inpatient unit. Measures included the Mini-Mental State Examination, Cohen-Mansfield Agitation Inventory, Cumulative Illness Rating Scale, Basic and Independent Activities of Daily Living, Positive and Negative Syndrome Scale for Schizophrenia, and the Initiation/Perseveration subscale of the Dementia Rating Scale. No significant differences existed in the character or severity of agitation among patients with Alzheimer's, vascular, alcohol-related and mixed dementia. Interestingly, patients with vascular dementia compared to patients with other dementias admitted for behavioral disturbances were less cognitively impaired and more medically burdened.

Biochemical characterization of gapB-encoded erythrose 4-phosphate dehydrogenase of Escherichia coli K-12 and its possible role in pyridoxal 5'-phosphate biosynthesis.

One step in de novo pyridoxine (vitamin B6) and pyridoxal 5'-phosphate biosynthesis was predicted to be an oxidation catalyzed by an unidentified D-erythrose-4-phosphate dehydrogenase (E4PDH). To help identify this E4PDH, we purified the Escherichia coli K-12 gapA- and gapB-encoded dehydrogenases to homogeneity and tested whether either uses D-erythrose-4-phosphate (E4P) as a substrate. gapA (gap1) encodes the major D-glyceraldehyde-3-phosphate dehydrogenase (GA3PDH). The function of gapB (gap2) is unknown, although it was suggested that gapB encodes a second form of GA3PDH or is a cryptic gene. We found that the gapB-encoded enzyme is indeed an E4PDH and not a second GA3PDH, whereas gapA-encoded GA3PDH used E4P poorly, if at all, as a substrate under the in vitro reaction conditions used in this study. The amino terminus of purified E4PDH matched the sequence predicted from the gapB DNA sequence. Purified E4PDH was a heat-stable tetramer with a native molecular mass of 132 kDa. E4PDH had an apparent Km value for E4P [Kmapp(E4P)] of 0.96 mM, an apparent kcat catalytic constant for E4P [kcatapp(E4P)] of 200 s-1, Kmapp(NAD+) of 0.074 mM, and kcatapp(NAD+) of 169 s-1 in steady-state reactions in which NADH formation was determined. From specific activities in crude extracts, we estimated that there are at least 940 E4PDH tetramer molecules per bacterium growing in minimal salts medium plus glucose at 37 degrees C. Thin-layer chromatography confirmed that the product of the E4PDH reaction was likely the aldonic acid 4-phosphoerythronate. To establish a possible role of E4PDH in pyridoxal 5'-phosphate biosynthesis, we showed that 4-phosphoerythronate is a likely substrate for the 2-hydroxy-acid dehydrogenase encoded by the pdxB gene. Implications of these findings in the evolution of GA3PDHs are also discussed. On the basis of these results, we propose renaming gapB as epd (for D-erythrose-4-phosphate dehydrogenase).

Increased detection of anaerobic bacteria with use of fiberoptic light.

The use of fiberoptic light in association with a movable stereoscope and gloveless chamber has greatly enhanced our ability to detect and manipulate minute bacterial colonies on plates used for primary cultures of anaerobes as early as 24 hours postinoculation. Additional benefits resulting from this association are ease in screening anaerobic plates, increased work space within the chamber, and an additional light source that can be used independent of the stereoscope.

The spectrum of olfactory neural tumors. A light-microscopic immunohistochemical and ultrastructural analysis.

Twenty-eight malignant olfactory neural tumors representative of the histologic spectrum commonly designated as olfactory neuroblastoma were subdivided into two groups: Group I closely resembling classical neuroblastoma (20 cases), and Group II exhibiting neuroendocrine features (eight cases). Immunohistochemically, the tumors were analyzed by using antibodies to keratin, neurofilament protein, S-100, and neuron specific enolase. Neuron specific enolase was the most consistently positive in both groups. Single S-100 positive cells, within or at the edges of tumor nests, often corresponded ultrastructurally to Schwann cells at the tumor-stroma interface. Keratin and neurofilament proteins were expressed singly or together by a small number of cases in both groups. All 11 tumors examined ultrastructurally exhibited neuronal processes containing dense-core granules. The results indicate the following: (a) the reliable diagnostic utility of electron microscopy; (b) the frequent occurrence of Schwann cells in these tumors despite their inconspicuousness by light microscopy; and (c) the unexpected expression of keratin by tumors in both groups. The single or coexpression of keratin-neurofilament protein may define a subset of these tumors for which the clinical significance is presently unclear.