Roles of the apparent diffusion coefficient and tumor volume in predicting tumor grade in patients with choroid plexus tumors

Purpose

To explore the utility of the apparent diffusion coefficient (ADC) and tumor volume to predict histological grade and prognosis in patients with choroid plexus tumors.

Methods

ADC and tumor volumes were retrospectively evaluated in 25 patients with choroid plexus papilloma (CPP; WHO grade 1 [n?=?13]), atypical CPP (aCPP; grade 2 [n?=?8]), or choroid plexus carcinoma (grade 3 [n?=?4]) The prognostic roles of ADC and tumor volume were assessed.

Results

There were significant differences in mean and minimum ADC values, and tumor volume among the WHO grades (p?=?0.033, p?=?0.044, and p?=?0.014, respectively). Receiver-operating characteristic analysis revealed a mean cutoff ADC value ≤?1.397?×?10^?3 mm²/s for aCPP (sensitivity?=?0.667, specificity?=?0.923). Multiple linear regression analysis demonstrated that both mean ADC (β?=???0.455, p?=?0.005) and tumor volume (β?=?0.513, p?=?0.002) were correlated with WHO grade (adjusted R²?=?0.520, p?=?0.005). Kaplan-Meier curve analysis identified poorer survival in patients with WHO grade 2 and 3 tumors than in those with WHO grade 1 disease (p?=?0.049 and p?=?0.012, respectively). A mean ADC?≤?1.397?×?10^?3 mm²/s (p?=?0.001) and tumor volume 21.05 ml (p?=?0.031) predicted significantly poorer survival.

Conclusion

Mean ADC and tumor volume were correlated with WHO grade of choroid plexus tumors. A lower ADC value and a larger tumor volume predicted a poorer prognosis.

     

Double immunostaining with p63 and high-molecular-weight cytokeratins distinguishes borderline papillary lesions of the breast

Papillary breast lesions remain a source of diagnostic confusion because the full range of epithelial proliferations may arise within, or secondarily involve, papilloma. The expression of p63 and high-molecular-weight cytokeratins (HMWCK) was studied simultaneously in 33 papillary lesions including intraductal papilloma (IP, n = 10), atypical papilloma (AP, n = 8) and intraductal papillary carcinoma (IPC, n = 15) by double immunostaining. The myoepithelial cell nuclei were stained dark brown whereas the cytoplasms of usual ductal hyperplasia (UDH) and myoepithelium were stained purple. The myoepithelial layer was recognized as a dark brown dotted line at the epithelial stromal junction in all IP (10/10), most AP (7/8) and some IPC (7/15), suggesting that the retained myoepithelial layer in the papillary processes does not necessarily guarantee benignity. However, the malignant epithelial cells in AP and IPC were typically recognized as monotonous populations unstained with either chromogen. These monotonous cells contrasted with the proliferating cells of UDH in papilloma, which had intense purple cytoplasm in a mosaic-like fashion. The present data suggest that the double immunostaining with the two popular antibodies p63 and HMWCK is a useful tool for reproducible classification of papillary breast lesions.     

Response of the coronary artery to a small dose of ergonovine in variant angina

The response of the coronary artery to a small dose (0.01 mg) of ergonovine was observed in nine patients without variant angina and in 10 patients with variant angina. Coronary angiograms were obtained before and after small and larger (routinely used) doses of ergonovine. With the larger dose, all 10 patients with variant angina had total or subtotal spastic occlusion accompanied by angina and ECG changes. Excluding the site of spastic occlusion produced by the larger dose of ergonovine, diameters of proximal, middle, and distal segments in each major coronary artery were measured before and after a small dose of ergonovine. The mean percentage of change in diameter (diameter before - diameter after a small dose of ergonovine)/diameter before a small dose of ergonovine X 100% in patients without variant angina was not significantly different from that in patients with variant angina (5.2 +/- 9.5% vs 7.0 +/- 11.9%, respectively). However, in patients with variant angina, a small dose of ergonovine produced a percentage of change in diameter of 39.8 +/- 15.3% at the site of spastic occlusion included by a larger dose of ergonovine, compared with that of 7.0 +/- 11.9% in the remaining non-spastic coronary arteries (p less than 0.05). These results indicate that patients with variant angina have local segments which respond differently to ergonovine from the remaining segments of coronary arteries. Clinically, this observation might be helpful in determining the angiographic positivity to ergonovine.     

Diffusion-weighted MR imaging of posterior reversible leukoencephalopathy syndrome: a pictorial essay

Posterior reversible leukoencephalopathy syndrome is characterized by reversible white matter lesions. However, ischemic injury with irreversible damage may occur. This pictorial essay illustrates MR features associated with posterior reversible leukoencephalopathy syndrome. We will emphasize the role of diffusion-weighted imaging for the discrimination of irreversible ischemic injury from reversible vasogenic edema.     

Ghrelin is present in pancreatic alpha-cells of humans and rats and stimulates insulin secretion.

Ghrelin, a novel growth hormone-releasing peptide isolated from human and rat stomach, is a 28-amino acid peptide with a posttranslational acylation modification that is indispensable for stimulating growth hormone secretion by increasing intracellular Ca(2+) concentration. It also functions in the regulation of feeding behavior, energy metabolism, and gastric acid secretion and motility. Using two different antibodies against the NH(2)- and COOH-terminal regions of ghrelin, we studied its localization in human and rat pancreas by immunohistochemistry. Ghrelin-immunoreactive cells were identified at the periphery of pancreatic islets in both species. Ghrelin co-localized exclusively with glucagon in rat islets, indicating that it is produced in alpha-cells. We identified ghrelin and des-acyl ghrelin in the rat pancreas using reverse-phase high-performance liquid chromatography combined with two radioimmunoassays. We also detected mRNA encoding ghrelin and its receptor in the rat pancreatic islets. Ghrelin increased the cytosolic free Ca(2+) concentration in beta-cells and stimulated insulin secretion when it was added to isolated rat pancreatic islets. These findings indicate that ghrelin may regulate islet function in an endocrine and/or paracrine manner.     

Ethnic differences in five intronic polymorphisms associated with arsenic metabolism within human arsenic (+3 oxidation state) methyltransferase (AS3MT) gene

Human arsenic (+ 3 oxidation state) methyltransferase (AS3MT) is known to catalyze the methylation of arsenite, and intronic single-nucleotide polymorphisms (SNPs: G7395A, G12390C, T14215C, T35587C, and G35991A) in the AS3MT gene were shown to be related to inter-individual variation in the arsenic metabolism. In the present study, the genotyping for these SNPs was developed using the polymerase chain reaction and restriction fragment length polymorphism technique. Applying this method, the genotype distribution among the Ovambo, Turkish, Mongolian, Korean, and Japanese populations was investigated, and our results were compared with those from other studies. G7395, G12390, T35587, and A35991 were predominant among the five populations in our study. However, a previous study in Argentina, C12390 and G35991 showed the highest allele frequency among the eight populations studied in other studies. The dominant allele of T14215C differed among populations: the T14215 allele was predominant in Argentina, the allele frequency of C14215 was higher than that of T14215 among Turks, Mongolians, Europeans, and American ancestry. In Korea and Japan, similar allele frequencies were observed in T14215 and C14215. Higher allele frequencies were observed in haplotype G7395/G12390/C14215/T35587 with frequencies of 0.40 (Turks), 0.28 (Mongolians), and 0.23 (Koreans). On the other hand, the allele frequency for G7395/G14215/T35587/A35991 was the highest among the Ovambos (0.32), and the frequency for G7395/G12390/C35587/G35991 was the highest among the Japanese (0.27). It is noteworthy that the Japanese haplotype differs from that of the Koreans and Mongolians, which indicates the importance of investigating other intronic polymorphisms in AS3MT, especially in Asians.     

Corticofugal projections to trigeminal motoneurons innervating antagonistic jaw muscles in rats as demonstrated by anterograde and retrograde tract tracing

Little is known about the organization of corticofugal projections controlling antagonistic jaw muscles. To address this issue, we employed retrograde (Fluorogold; FG) and anterograde (biotinylated dextran amine; BDA) tracing techniques in rats. Three groups of premotoneurons were identified by injecting FG into the jaw-closing (JC) and -opening (JO) subdivisions of the trigeminal motor nucleus (Vmo). These were 1) the intertrigeminal region (Vint) and principal trigeminal sensory nucleus for JC nucleus; 2) the reticular region medial to JO nucleus (RmJO) for JO nucleus; and 3) the parabrachial (Pb) and supratrigeminal (Vsup) nuclei, reticular regions medial and ventral to JC nucleus, rostrodorsomedial oralis (Vor), and juxtatrigeminal region (Vjuxt) containing a mixture of premotoneurons to both the nuclei. Subsequently, FG was injected into the representative premotoneuron structures. The JC and JO premotoneurons received main afferents from the lateral and medial agranular fields of motor cortex (Agl and Agm), respectively, whereas afferents to the nuclei with both JC and JO premotoneurons arose from Agl also and from primary somatosensory cortex (S1). Finally, BDA was injected into each of the three cortical areas representing the premotoneuron structures to complement the FG data. The Agl and Agm projected to reticular regions around the Vmo, whereas the Pb, Vsup, Vor, and Vjuxt received input from Agl. The S1 projected to the trigeminal sensory nuclei as well as to the Pb, Vsup, and Vjuxt. These results suggest that corticofugal projections to Vmo via premotoneuron structures consist of multiple pathways, which influence distinct patterns of jaw movements. J. Comp. Neurol. 514:368–386, 2009. © 2009 Wiley-Liss, Inc.