Corpus callosum and subcallosal-periventricular lesions in multiple sclerosis: detection with MR

Examination with magnetic resonance imaging of 40 patients with confirmed diagnoses of multiple sclerosis showed that corpus callosum involvement is common. Thirty percent of the patients had focal callosal lesions similar to those described in the pathology literature. Long, inner callosal-subcallosal lesions were found in 55% of patients. These lesions had signal characteristics similar to those of noncallosal periventricular lesions. Diffuse moderate to severe atrophy of the corpus callosum was noted in 40% of patients, with one exception concurrent with inner callosal lesions. The nature of the inner callosal lesions is not known, since these lesions are not typically described in the literature. These lesions may represent demyelination or increased water content and may be the precursor to atrophy that progresses from the ependymal surface toward the outer fibers of the corpus callosum.     

国产檀香中α-反式香柠烯醇化学结构研究

从国产檀香木Santalum ablum L.分得一个新倍半萜醇,根据光谱(IR,MS,¹H-¹H COSY,¹³C-¹H COSY和¹H-¹H NOESY)解析,确定了它的化学结构和相对立体化学为9(10)-顺,α-反式香柠烯醇[9(10)Z,α-trans-bergamotenol](Ia)。     

Alzheimer disease: quantitative analysis of I-123-iodoamphetamine SPECT brain imaging

To enable a more quantitative diagnosis of senile dementia of the Alzheimer type (SDAT), the authors developed and tested a semiautomated method to define regions of interest (ROIs) to be used in quantitating results from single photon emission computed tomography (SPECT) of regional cerebral blood flow performed with N-isopropyl iodine-123-iodoamphetamine. SPECT/IMP imaging was performed in ten patients with probable SDAT and seven healthy subjects. Multiple ROIs were manually and semiautomatically generated, and uptake was quantitated for each ROI. Mean cortical activity was estimated as the average of the mean activity in 24 semiautomatically generated ROIs; mean cerebellar activity was determined from the mean activity in separate ROIs. A ratio of parietal to cerebellar activity less than 0.60 and a ratio of parietal to mean cortical activity less than 0.90 allowed correct categorization of nine of ten and eight of ten patients, respectively, with SDAT and all control subjects. The degree of diminished mental status observed in patients with SDAT correlated with both global and regional changes in IMP uptake.     

Ultrastructural study of eosinophils from patients with the hypereosinophilic syndrome: a morphological basis of hypodense eosinophils

We investigated the ultrastructural characteristics and the granule major basic protein (MBP) content of hypodense eosinophils from patients with the hypereosinophilic syndrome who had at least 90% hypodense eosinophils in their peripheral blood and compared these cells to normodense eosinophils from normal persons. The hypodense cells (density less than 1.082) contained significantly less MBP than normodense (density greater than 1.082) eosinophils (P less than .001) as measured by radioimmunoassay (RIA). Electron microscopic examination demonstrated a mean of 25.0 +/- 4.4 (X +/- 1 SD) granules per hypodense cell, compared to 30.6 +/- 8.4 granules per cell in the normodense group (P less than .1). The most striking difference between the hypodense and normodense eosinophils was the small individual granule size (X = .14 +/- .05 v .26 +/- .05 micron 2, respectively, P less than .001), and the smaller total granule area (3.2 +/- 1.8 vs 7.7 +/- 3.1 micron 2, respectively, P less than .001). Because the cytoplasmic areas were similar in the two groups, the mean percent area of cytoplasm occupied by granules was significantly lower in the hypodense group (P less than .001). The finding of consistently smaller granules in the presence of equal or fewer granules per cell in the hypodense eosinophils may explain the lower MBP content and thus provide a morphologic basis for the low density of eosinophils in patients with the hypereosinophilic syndrome.     

cDNA cloning and chromosome mapping of the human Fe65 gene: interaction of the conserved cytoplasmic domains of the human beta-amyloid precursor protein and its homologues with the mouse Fe65 protein

Using the yeast two hybrid system, a mouse embryo cDNA library was screened for proteins that interact with the C-terminus of the human beta-amyloid precursor protein (beta PP). A fusion protein was identified that interacts specifically with the cytoplasmic domain of beta PP and does not interact with the beta-amyloid region. The protein encoded by this partial mouse cDNA is identical to the C-terminus of the rat Fe65 protein. This mouse protein also interacts with the homologous C-terminal domains of the mouse amyloid precursor-like proteins, APLP1 and APLP2. These conserved cytoplasmic regions contain a common amino acid motif, Asn-Pro-Thr-Tyr, which has previously been shown to influence both the secretion and internalization of beta PP. Fe65 has been implicated in regulatory and cell signaling mechanisms because it contains two different motifs involved in protein binding, a WW domain (a variant of Src homology 3 domains) and a phosphotyrosine interaction domain (PID). Interestingly, the PID domain binds to the same motif present in the conserved cytoplasmic domains of the beta PP and beta PP-like proteins. RNA analyses reveal that Fe65 is predominantly expressed in brain and in the regions most affected by Alzheimer's disease (AD)-associated neuropathology. The human Fe65 mRNA was cloned from a fetal brain cDNA library. The message encodes a protein of 735 amino acids that is 95% identical to the rat Fe65 protein. The human Fe65 gene was mapped on human metaphase chromosomes to band 11p15 using fluorescence in situ hybridization.      

Pattern of proteinuria in IgA nephropathy

Summary: Proteinuria is one of the bad prognostic indices in IgA nephritis (IgAN). This study compares the pattern of protein excretion in 10 patients with IgAN (IA) with that 5 years later (IB), when they developed renal impairment or hypertension. The pattern of proteinuria was analysed by SDS-PAGE and isoelectric focusing (IEF) and assayed for orosomucoid, α-1-microglobulin, retinol-binding protein, lysozyme, beta-2-microglobulin and N-acetyl-β-D-glucosaminidase activity. The data suggest that the changing pattern of proteinuria from IgA₁ to IgA₂ may reflect hyperfiltration as well as tubular injury.