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Objective: The purpose of this study is to investigate radiologic findings of struma ovarii, and to correlate both CT and MR findings. Materials and Methods: MR images of 26 cases were retrospectively reviewed. Post-contrast enhanced T1-weighted images were available in 17 patients. CT images, including seven non-contrast and eleven post-contrast studies, were available for review in 13 cases. Results: All 26 tumors appeared as well-defined cystic tumors with solid components, which were multilobulated surfaces in 19 and smooth surfaces in seven. Twenty-four was multicystic, whereas two were unilocular. The solid components were recognized as thickened septi or walls in 23 and a mass in three tumors. On T2-weighted images, loculi of prominent low intensity were recognized in 16 tumors. On T1-weighted images, the punctuate foci of high intensity were recognized in 24 tumors in or adjacent to the solid components. Ascites was present in only one lesion. In six of seven cases with non-contrast CT images, high attenuation areas were recognized. In five of these six tumors, high attenuation areas corresponded to the areas of prominent low intensity and the solid components on T2-weighted images. In seven cases with CT, curvilinear calcifications were recognized in the solid components. Conclusion: Struma ovarii typically presents as a lobulated multicystic lesion with solid components. The tumors frequently include loculi of low intensity on T2-weighted images and punctuate foci of high intensity on T1-weighted images. On CT, high attenuation areas and calcifications in the solid components are common findings. [ABSTRACT FROM AUTHOR]

BACKGROUND: Three major causative genes have been implicated as the cause of early-onset familial Alzheimer's disease (AD): the amyloid precursor protein gene (APP), presenilin-1 (PSEN1) and PSEN2. Although rare, a tau-related dementia with mutations in the microtubule-associated protein tau gene (MAPT) has been identified in patients showing clinical presentations similar to those of AD. METHODS: We performed mutational analysis of APP, PSEN1, PSEN2, and MAPT in 10 Japanese families with early-onset dementia clinically diagnosed as probable Alzheimer's disease. RESULTS: In 4 index patients, we identified 4 missense PSEN1 mutations, namely, L286V, G378E, L381V, and L392V. The mean age at onset in the patients with PSEN1 mutations was 39 years. In 2 families, we found the R406W mutation in MAPT. The mean age at onset of the patients carrying the R406W mutation was 52 years, and they presented with the peculiar AD-like phenotype without apparent behavioral or language problems. CONCLUSION: These observations suggest that although PSEN1 mutations are the most frequent cause, the MAPT R406W mutation is an important cause of early-onset familial dementia clinically diagnosed as AD. Differentiation of patients with the MAPT mutation from AD patients by genetic testing would be meaningful, considering that a different therapeutic approach should be applied. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder. Accumulating evidence has shown that 43kDa TAR-DNA-binding protein (TDP-43) is the disease protein in ALS and frontotemporal lobar degeneration. We previously reported a familial ALS with Bumina bodies and TDP-43-positive skein-like inclusions in the lower motor neurons; these findings are indistinguishable from those of sporadic ALS. In three affected individuals in two generations of one family, we found a single base-pair change from A to G at position 1028 in TDP-43, which resulted in a Gln-to-Arg substitution at position 343. Our findings provide a new insight into the molecular pathogenesis of ALS. [ABSTRACT FROM AUTHOR]

Nicotine treatment triggers calcium influx into neuronal cells, which promotes cell survival in a number of neuronal cells. Phosphoinositide (PI) 3-kinase and downstream PI3-kinase target Akt have been reported to be important in the calciummediated promotion of survival in a wide variety of cells. We investigated the mechanisms of nicotine-induced phosphorylation of Akt in PC12h cells, in comparison with nicotine-induced ERK phosphorylation. Nicotine induced Akt phosphorylation in a dose-dependent manner. A nicotinic acetylcholine receptor (nAChR) α7 subunit-selective inhibitor had no significant effect on nicotine-induced Akt phosphorylation, while a non-selective nAChR antagonist inhibited the phosphorylation. L-type voltage-sensitive calcium channel (VSCC) antagonists, calmodulin antagonist, and Ca[sup 2+]/calmudulin-dependent protein kinase (CaM kinase) inhibitor prevented the nicotine-induced Akt phosphorylation. Three epidermal growth factor receptor (EGFR) inhibitors prevented the nicotine-induced phosphorylation of both extracellular signal-regulated protein kinase (p42/ 44 MAP kinase, ERK) and Akt. In contrast, an inhibitor of the Src family tyrosine kinase prevented the nicotine-induced Akt phosphorylation but not ERK phosphorylation. These results suggested that nicotine induces the activation of both PI3kinase/Akt and ERK pathways via common pathways including non-α7-nAChRs, L-type VSCC, CaM kinase II and EGFR in PC12h cells, but Src family tyrosine kinases only participate in the pathway to activate Akt. [ABSTRACT FROM AUTHOR]

We have investigated mechanisms of nicotine-induced phosphorylation of extracellular signal-regulated protein kinase (p42/44 MAP kinase, ERK) and cAMP response element binding protein (CREB) in PC12h cells. Nicotine transiently induced ERK phosphorylation at more than 1 µm. The maximal level of nicotine-induced ERK phosphorylation was lower than that of the membrane depolarization induced and, to a great extent, the nerve growth factor (NGF)-induced ERK phosphorylation. Nicotinic acetylcholine receptor (nAChR) α7 subunit-selective inhibitors had no significant effect on nicotine-induced ERK phosphorylation. l-Type voltage-sensitive calcium channel antagonists inhibited nicotine-induced ERK phosphorylation. Calcium imaging experiments showed that α7-containing nAChR subtypes were functional at 1 µm of nicotine in the nicotine-induced calcium influx, and non-α7 nAChRs were prominent in the Ca[sup 2+] influx at 50 µm of nicotine. An expression of dominant inhibitory Ras inhibited nicotine-induced ERK phosphorylation. A calmodulin antagonist, a CaM kinase inhibitor, a MAP kinase kinase inhibitor inhibited nicotine-induced ERK and CREB phosphorylation. The time course of the phosphorylation of CREB induced by nicotine was similar to that of ERK induced by nicotine. These results suggest that non-α7 nAChRs are involved in nicotine-induced ERK phosphorylation through CaM kinase and the Ras-MAP kinase cascade and most of the nicotine-induced CREB phosphorylation is mediated by the ERK phosphorylation in PC12h cells. [ABSTRACT FROM AUTHOR]

Brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1) act on various neurons of the CNS as neurotrophic factors promoting neuronal differentiation and survival. We examined the survival-promoting effects of BDNF and IGF-1 on serum deprivation-induced death in cultured cerebral cortical neurons, and compared the intracellular signaling pathways stimulated by BDNF and IGF-1 in the neurons. We found that the survival-promoting effect of BDNF was much weaker than that of IGF-1 in serum deprivation-induced death of cultured cortical neurons. We found no differences in the levels of phosphatidylinositol 3-kinase (PtdIns3-K) activity or Akt (also called PKB) phosphorylation induced by BDNF and IGF-1 in the cultured cortical neurons, although many reports suggest that PtdIns3-K and Akt are involved in survival promotion. In addition, phosphorylation signals of mitogen-activated protein kinase (MAPK) and cAMP responsive element-binding protein (CREB), which have also been reported to be involved in survival promotion, were stimulated by BDNF much more potently than by IGF-1. These results show that there may be, as yet unidentified, intracellular signaling pathways other than the PtdIns3-K-Akt, MAPK and CREB signaling, to regulate survival promotion. These unidentified signaling pathways may be responsible for the distinct strengths of the survival-promoting effects of BDNF and IGF-1. [ABSTRACT FROM AUTHOR]

Endotoxaemia was investigated by the Limulus assay in 42 cirrhotic patients with ascites and in 33 without ascites. The incidence of endotoxaemia in the former group (59.5%) was significantly (P less than 0.05) higher than in the latter (36.4%). Correlation between endotoxaemia and specific gravity and concentrations of total protein, albumin, and globulin in ascitic fluid was studied in the group with ascites. The specific gravity of ascites in 25 patients with endotoxaemia was significantly greater than that in 17 patients without endotoxaemia (P less than 0.01). The concentration of total protein in patients with endotoxaemia (13.95 +/- 7.18 milligram, mean +/- SD) was nearly twice as high (P less than 0.01) as in patients without endotoxaemia (7.49 +/- 3.60 milligram). The protein content of those who showed reactions greater or equal to 2(+) in the Limulus assay (16.78 +/- 7.14 milligram) was a significantly (P less than 0.05) higher than in those with 1(+) reaction (11.26 +/- 6.33 milligram). Moreover, the concentration of albumin in patients with endotoxaemia (7.68 +/- 4.60 milligram) was more than twice that of the patients without endotoxaemia (3.39 +/- 1.58 milligram, P less than 0.01). On the other hand, globulin concentration in patients with endotoxaemia was 1.6 times that of patients without endotoxaemia (P less than 0.01). Similar differences were noted between endotoxaemic and non-endotoxaemic patients in the ascites-to-serum ratio in protein, albumin, and globulin. These results suggest that in liver cirrhosis endotoxaemia may cause an increase in protein concentrations in ascitic fluid, and that it may be a precipitating factor in the formation of ascites. [ABSTRACT FROM PUBLISHER]