[Distal pulmonary vessels demonstration by magnetic resonance angiography and its usefulness in the diagnosis of peripheral nodules]

To evaluate the usefulness of MRA in the diagnosis of peripheral pulmonary nodules, 18 lung cancers and 12 old inflammatory nodules were studied employing multiplanar fast radiofrequency spoiled gradient echo sequence (SPGR) with phased array coils. For each case, 12 images in coronal and sagittal sections were obtained after administration of Gd-DTPA, and original images, maximum intensity projection (MIP) images and multiplanar reconstruction (MPR) images were used for the interpretation. In ten cases, MRA images were compared with resected specimens and we found that the minimum diameter of pulmonary vessels which could be demonstrated by our method was about 1.5mm. As the results of the interpretation of MRA images in 30 cases, venous involvement, which is one of the classical important findings indicative of malignancy, was clearly demonstrated in 15 of 18 (83%) lung cancers, whereas such involvement was detected in only 3 of 12 (25%) inflammatory nodules. Pulmonary MRA, especially MIP and MPR images could make it easy to identify involved vessels, and proved to be useful in differentiating pulmonary nodules.

[Aberrant expression of HLA-DR antigens on acinar and ductal epithelial cells of salivary glands in Sjögren's syndrome]

The major histocompatibility complex (MHC) class II antigens have been reported to play an important role in antigen presentation to T cells and influence the susceptibility to several autoimmune diseases, including Sjögren's syndrome (SS). In this paper, an aberrant expression of MHC class II antigens, especially HLA-DR antigens, on salivary glands of SS is described. HLA-DR antigens were immunohistochemically detected on acinar and ductal epithelial cells of SS patients but not those of healthy controls. This expression was observed in proximity to the periphery of dense lymphocytic infiltrates but sometimes not associated with lymphocytic infiltrates. These results are consistent with recent findings of HLA-DR antigen expression on target organs of various autoimmune diseases. Finally, we discussed a pathogenic role of HLA-DR antigens, aberrantly expressed on target organs of SS.

Plasma adrenomedullin in patients with primary aldosteronism

Adrenomedullin (AM) is a novel hypotensive peptide originally isolated from the pheochromocytoma tissue of humans. To examine the pathophysiological role of AM in primary aldosteronism (PA), the plasma concentration of AM in patients with PA was measured with a specific radioimmunoassay and compared to that in age- and sex-matched healthy normotensive subjects. In addition, the concentrations of AM as well as catecholamines in the plasma from both the adrenal vein and the inferior vena cava (IVC) were measured to determine whether or not the circulating AM in these PA patients is supplied from the adrenal medulla, which contains a much higher concentration of AM than any other human tissue does. The plasma concentration of AM in the PA patients (4.57 +/- 0.32 fmol/mL, n = 6) was significantly (P < .01) higher than that in the healthy subjects (3.06 +/- 0.20 fmol/mL, n = 12). A significant positive correlation (r = 0.62, P < .01) was observed between the mean blood pressure and the plasma AM level. The AM concentration in plasma from the adrenal vein was almost the same level as that from the IVC although the concentrations of both epinephrine and norepinephrine in the adrenal vein were much higher than those in the IVC. Therefore, it seems unlikely that the plasma AM in the PA patients is mainly supplied from the adrenal medulla. Judging from the potent hypotensive activity of AM, the present findings suggest that AM participates in defense mechanisms acting against the elevation of blood pressure in the patients with PA.

[Cytokine mRNA expression in the labial glands of patients with Sjögren's syndrome]

It has been found that the pattern of cytokine mRNA expression was closely associated with the initiation and the progression of the disease process. The cytokine mRNA expression in the labial glands of patients with Sjögren's syndrome was examined by a PCR-based method. Th1 cytokines, such as IL-2 and IFN-gamma, were consistently detected in all patients examined, while Th2 cytokines, such as IL-4 and IL-5, were detected in some cases with strong B cell accumulation in the labial glands. These results suggest that Th1 cytokines are essential in the induction and/or maintenance of the disease, while Th2 cytokines are involved in the progression of the disease process. Other studies were also reviewed and a role of cytokines, produced by T cells and the target organ, was discussed.

A randomized trial of transcutaneous extraction atherectomy in femoral arteries: intravascular ultrasound observations

OBJECTIVES

The purpose of this study was to test the hypothesis that in occlusions of the superficial femoral artery, removal of atherosclerotic plaque would result in a higher long-term patency rate compared to balloon dilatation alone. A secondary hypothesis was that long term patency would be proportional to the amount of plaque removed.

METHODS

A randomized controlled study of patients with occluded superficial femoral arteries was performed comparing balloon dilatation alone versus a 2.7 mm or a larger (4.0 mm or 4.7 mm) transcutaneous extraction catheter (TEC) atherectomy device followed by balloon dilatation. The effect of these devices on plaque area was assessed directly by intravascular ultrasound imaging.

RESULTS

The mean occlusion length was 19.4 cm +/- 11.7 cm. The mean lumen area increased from 4.7 mm2 to 15.1 mm2, primarily due to balloon dilatation, but the mean atheroma area of 19.8 mm2 did not change with either size of TEC device. Although the initial procedure success rate was high (79%), the 6 month patency was only 45%. There was no difference in 6 month patency between the 3 groups.

CONCLUSIONS

The data indicate that the TEC atherectomy devices do not remove a significant amount of atherosclerotic plaque in occluded superficial femoral arteries. The 6 month patency is no different with these atherectomy devices than with balloon dilatation alone. The larger (4.0 mm or 4.7 mm) TEC device does not remove any more tissue than the smaller (2.7 mm) device. The use of intravascular ultrasound to quantitate the effects of this atherectomy device provides important insights into the mechanism of action and lack of efficacy of the TEC atherectomy catheter.

Beta-cell function and replication in spontaneously hypertensive rats

We examined beta-cell function and replication in spontaneously hypertensive rats (SHR) and age-matched Wistar-Kyoto rats (WKY). Rats were subjected to 90% pancreatectomy (Px) or sham operation at the age of 8 weeks, and islet function and regeneration were examined 4 weeks after surgery. Plasma glucose levels were higher in SHR than in WKY (509 +/- 38 v 325 +/- 109 mg/dL, P < .0001) 1 week after Px and throughout the experimental period. Plasma glucose responses to intravenous injection of glucose (0.5 g/kg body weight) were not different in the sham-operated animals of the two strains, whereas plasma insulin responses were greater in SHR than in WKY. No insulin responses to glucose were observed in either strain of Px rats. The insulin content of the remnant equivalent (6.7 +/- 2.1 v 4.2 +/- 0.4 micrograms, P < .05) and whole pancreas (156.7 +/- 10.7 v 123.8 +/- 23.5 micrograms, P < .01) in sham-operated rats was greater in SHR than in WKY. However, insulin content was lower (P < .05) in Px-SHR (1.0 +/- 0.2 microgram) than in Px-WKY (3.9 +/- 1.7 micrograms). Histological examination showed that fibrotic degeneration of islets was much greater in Px-SHR than in Px-WKY. These data strongly suggest that the beta cells of SHR were more vulnerable to reduction of islet mass than those of WKY. Our data also suggest that hyperinsulinemia and/or insulin resistance in SHR has a deleterious effect on beta-cell replication.

Body fat distribution in women with polycystic ovary syndrome

OBJECTIVE

To investigate body fat distribution in women with polycystic ovary syndrome (PCOS).

METHODS

Body weight, body mass index (BMI), and six indices of body fat measured by dual-energy x-ray absorptiometry were compared in 40 women with PCOS and 97 age-matched controls. The possible correlations between the body fat characteristics and serum androgen levels were evaluated in the 40 PCOS women. Body fat distribution was classified into upper- (N = 24) and lower-half body type (N = 16), and androgen levels and the incidence of hirsutism were compared in the two types.

RESULTS

The BMI, body fat ratio, upper-half body fat ratio, and upper-half/lower-half body fat ratio were significantly higher in PCOS women than in controls. After adjustment for age, height, and body weight, the upper-half/lower-half body fat ratio was still significant (P < .001). The PCOS subjects exhibited a significant positive correlation between the upper-half/lower-half body fat ratio and dehydroepiandrosterone-sulfate (DHEA-S) levels (r = 0.607, P < .01) as well as testosterone levels (r = 0.585, P < .05). Dehydroepiandrosterone-sulfate and testosterone levels were significantly higher in those with the upper-half body type than in those with the lower-half body type (P < .001). After adjustment for confounding variables, only DHEA-S was still significantly higher in this body type (P < .05).

CONCLUSION

Serum DHEA-S levels seem to be associated with upper-half body fat distribution in women with PCOS, irrespective of body weight.

[A bronchial carcinoid tumor in a patient with a high level of serum carcinoembryonic antigen]

A 76-year-old man was admitted to our hospital with a cough and bloody sputum. The level of serum carcinoembryonic antigen (CEA) was high (528.6 ng/ml), and the chest X-ray film revealed a large mass shadow in the lower left lung field. Bronchoscopic examination revealed complete obstruction of the left basal bronchus by a polypoid tumor coated with a white necrotic substance. Histologic examination of a specimen of the tumor led to the diagnosis of carcinoid. Left lower lobectomy and S5 segmentectomy were done. The operative diagnosis was also histologically carcinoid tumor. Immunohistochemical staining for CEA showed strong reactivity in tumor cells. The serum CEA level was normal when measured 2 months after the operation. Therefore, the excess serum CEA measured before the operation was probably secreted by tumor cells.

[Histopathological studies on senile plaques and cerebral amyloid angiopathy in aged cynomolgus monkeys]

The incidence and morphological characteristics of senile plaque and amyloid angiopathy in the cerebrum of six aged cynomolgus monkeys (Macaca fascicularis), 20 to 29 years old, were studied histopathologically and immunohistochemically. By periodic acid methenamine silver stain (PAM) and alkaline Congo red stain, senile plaques were detected in 5 out of 6 cases, and 3 of them were positive for amyloid in the wall of capillaries and arterioles in the cerebral cortex. Senile plaques were classified into three types. Mature plaques, including classical and primitive types, were more frequently observed than the immature diffuse type. Senile plaques were often seen in the cortex of temporal lobe, putamen and head of caudate nucleus. Since mature types of senile plaques were seen frequently around vascular amyloid deposition and no amyloid angiopathy was detected in the areas without senile plaques, the close relation between senile plaque of the mature type and amyloid angiopathy might be considered. All senile plaques and amyloid angiopathy were positively stained immunohistochemically with antibody against amyloid beta-protein (A beta P) 1-40 synthetic peptide, but all diffuse and some primitive plaques were negative for antibody against A beta P 8-17 synthetic peptide. Neither senile plaque nor amyloid angiopathy was detected in the cerebrum of 15 young monkeys, 9 to 11 years old, examined as controls.

Thromboxane A2 synthetase inhibitors with histamine H1-blocking activity: synthesis and evaluation of a new series of indole derivatives

A novel series of N-substituted 3-(1H-imidazol-1-ylmethyl)indole carboxylic acid derivatives were prepared and evaluated for thromboxane A2 (TXA2) synthetase-inhibitory and histaminergic H1-blocking activity. Among the compounds synthesized, indole-6-carboxylic acid derivatives showed higher activities than the other positional isomers of carboxylic acid. 1-[3-(4-Benzhydryl-1-piperazinyl)propyl]-3-(1H-imidazol-1-ylmethyl )-1H-indole-6-carboxylic acid (12) had the strongest thromboxane synthetase inhibitory activity (IC50 = 5 x 10(-8) M) and H1-blocking activity (IC50 = 8 x 10(-9) M).

Hepatocyte growth factor--pleiotropic cytokine produced by human leukemia cells

Hepatocyte growth factor (HGF) was identified, purified and molecularly cloned as a potent mitogen for mature rat hepatocytes in primary culture. It is one of the largest cytokines and is composed of disulfide-linked subunits of approximately 60 (heavy chain) and 35 kilodaltons (light chain). Recent observations revealed that HGF is mitogenic to various epithelial cells other than hepatocytes and to endothelial cells, and that it also acts as a motogen, morphogen and tumor-suppressor as well as a mitogen. These various biological activities of HGF are presumably transduced through the same receptor, c-Met, which is a member of the tyrosine kinase receptor family. Although it shows multiple biological activities on cells in culture, HGF is most likely the physiological hepatotrophic factor which triggers liver regeneration. It may also function as a renotrophic and pulmotrophic factor after tissue injury. HGF production in the liver, kidney and lung increases after injury to these organs. An elevated HGF level may act as an inducer of compensatory DNA synthesis. The regulation of HGF production is, therefore, important for the control of organ regeneration. HGF is produced mainly by mesenchymal cells such as fibroblasts and vascular smooth muscle cells. Various types of human leukemia cells also secrete HGF both in vitro and in vivo. Some biological activities of HGF on hematopoietic cells, including co-mitogenic activity on myeloid leukemia cell lines, were recently demonstrated. HGF gene expression and the protein production in leukemia and fibroblast cells are modulated by various cytokines and hormones. Those modulators may indirectly affect organ regeneration and other biological processes by controlling HGF production.

ATP increases extracellular dopamine level through stimulation of P2Y purinoceptors in the rat striatum

The effect of ATP on release of dopamine (DA) from rat striatum was studied using in vivo microdialysis. ATP increased the striatal extracellular levels of DA dose-dependently. These analogs produced an increase in DA according to this order of potency: 2-methylthio ATP > ATP > or = alpha,beta-methylene ATP > ADP > AMP > adenosine. Adenosine 5'-[beta, gamma imido]-triphosphate had a more prolonged effect on the increase in DA level than ATP. The ATP-induced increase in DA was inhibited by adding suramin, a nonselective P2 purinoceptor antagonist, and reactive blue 2, a P2Y purinoceptor antagonist, but not inhibited by xanthine amine congener, an adenosine receptor antagonist. Pertussis toxin reduced the increase in DA produced by ATP, which suggests that the P2 purinoceptor may be coupled with a G-protein in the rat striatum. Results suggest that P2Y purinoceptors may involve an ATP-induced increase in DA. The ATP-induced release of DA was tetrodotoxin-sensitive, Ca(2+)-dependent and was abolished by omega-conotoxin GVIA, indicating that the opening of voltage-sensitive Na+ channel and the Ca2+ influx through the N-type voltage-dependent calcium channel are both required for the ATP-induced increase in DA. The ATP-induced increase in DA is presumably due to the release of DA via the stimulation of P2Y purinoceptors in the rat striatum.

AIDS-associated Kaposi's sarcoma (KS) cells express oncostatin M (OM)-specific receptor but not leukemia inhibitory factor/OM receptor or interleukin-6 receptor. Complete block of OM-induced KS cell growth and OM binding by anti-gp130 antibodies

Oncostatin M (OM), which shares functional similarity and structural homology to leukemia inhibitory factor (LIF) and interleukin-6 (IL-6), functions as a potent growth factor for AIDS-associated Kaposi's sarcoma-derived cells (AIDS-KS cells). OM was also suggested to bind to the LIF receptor (LIF/OM receptor), which consists of a signal transducing subunit for LIF and IL-6 (gp130) and a LIF receptor alpha-subunit. Recent studies indicate that IL-6 has growth-stimulating activity for AIDS-KS cells. However, we find that AIDS-KS cell growth is exclusively induced by OM and not by LIF or IL-6. We also observed the lack of binding properties of AIDS-KS cells for LIF and IL-6. Scatchard plots revealed the existence of two affinity classes of OM receptor sites on AIDS-KS cells, with Kd values of 6-12 pM (high affinity) and 521-815 pM (low affinity). In competition binding studies, we find that the OM-specific receptor, but not the LIF/OM receptor, contributes to the OM-specific growth stimulation of AIDS-KS cells. We also noted that anti-gp130 antibodies can completely abolish OM-induced growth stimulation of AIDS-KS cells as well as OM binding to AIDS-KS cells. PCR amplification clearly revealed high levels of gp130 expression in AIDS-KS cells, while the transcript of LIF receptor alpha-subunit or IL-6 receptor alpha-subunit was not observed. Therefore, we conclude that (a) AIDS-KS cells express the OM-specific receptor with high and low affinity, but not the LIF/OM receptor; (b) gp130 on AIDS-KS cells plays a key role in OM binding and signaling on the OM-specific receptor; and (c) the lack of biological response of AIDS-KS cells to IL-6 and LIF can be explained by the absence of the IL-6 and LIF/OM receptors. All this evidence shows the correlation of OM-specific biological activity with expression of the OM-specific receptor and the involvement of gp130 on this receptor, as based on findings in in vitro growth assays and binding experiments for AIDS-KS cells.

Hepatocellular carcinoma associated with lupoid hepatitis: a review of Japanese reports

A 66-year-old woman was diagnosed as having lupoid hepatitis due to the presence of hypergammaglobulinemia, lupus erythematosus cells, and positivity for antinuclear, anti-DNA, and anti-smooth muscle antibodies. None of the serum hepatitis B markers were positive. Symptomatic relief was obtained by prednisolone administration. Five years after the diagnosis of lupoid hepatitis, hepatocellular carcinoma (HCC) was detected by ultrasonography and computed tomography, after which hepatectomy was performed. Although transcatheter arterial embolization was done on two occasions and repeat hepatectomy was performed twice for recurrent HCC, her liver function remained good with the prednisolone treatment. Antibody for hepatitis C virus has been negative since our first check in 1992. As of this writing, the patient has been alive and well 6 years and 2 months after the first hepatectomy. There have been no previous reports of 6-year survival after hepatectomy for HCC associated with lupoid hepatitis.

Effect of (Z)-11-[3-(dimethylamino) propylidene]-6,11-dihydrodibenz[b,e]oxepin-2-acetic acid hydrochloride on experimental allergic conjunctivitis and rhinitis in rats and guinea pigs

The effect of KW-4679 (Z)-11-[3-(dimethylamino) propylidene]-6,11-dihydrodibenz [b,e] oxepin-2-acetic acid hydrochloride, CAS 140462-76-6; proposed INN: olopatadine) on experimental conjunctivitis and rhinitis was studied in comparison with that of ketotifen (CAS 34580-14-8) using guinea pigs and rats, respectively. KW-4679 was effective in inhibiting the antigen- and histamine-induced conjunctivitis by both oral and topical administrations. These effects of KW-4679 were somewhat more potent than those of ketotifen. KW-4679 as well as ketotifen was more effective in inhibiting the histamine-induced conjunctivitis than that seen in antigen-induced conjunctivitis when they were given topically. KW-4679 inhibited the increased dye leakage into the nasal cavity induced not only by antigen in actively sensitized rats but also by histamine perfusion in non-sensitized rats by oral and topical administrations. Similar to ketotifen, the effect of KW-4679 on histamine-induced increase in dye leakage was almost same as that induced by antigen. The potency of KW-4679 was higher than that of ketotifen in the increased dye leakage induced by both antigen and histamine perfusion.

The positive nuclear staining observed with monoclonal antibody against PRAD1/cyclin D1 correlates with mRNA expression in mantle cell lymphoma

Recently, we produced a monoclonal antibody, 5D4, against the PRAD1/cyclin D1 product and suggested positive nuclear staining to be associated with mantle cell lymphoma (MCL). Now we have further characterized the specificity of this antibody and studied the relation of immunohistochemical detection to PRAD1/cyclin D1 mRNA expression and DNA rearrangement. Immunofluorescence and immunoblotting studies demonstrated the 5D4 antibody to be crossreactive with cyclin D2, but not cyclin D3. On immunostaining, 15 of 19 MCL cases (79%) presented the nuclear staining pattern and PRAD1/cyclin D1 mRNA expression was detected by Northern blot analysis in 12 of 15 MCL cases studied (80%): all cases with the mRNA expression showed the nuclear staining pattern. Southern blot analysis with 11q13 BCL-1 probes detected DNA rearrangements in 8 of 19 MCL cases (42%), all 8 exhibiting PRAD1/cyclin D1 mRNA expression. In 21 lymphoma cases of types other than MCL, neither the mRNA expression nor the nuclear staining were observed, although cytoplasmic staining was often apparent. These results indicated that positive nuclear staining of lymphoma cells by 5D4 antibody reflects PRAD1/cyclin D1 mRNA expression, and showed that this monoclonal antibody has diagnostic value for differentiating MCL from other types of lymphomas.

[Surgical treatment of aneurysms at basilar artery and posterior cerebral artery associated with moyamoya disease: a case report]

This report describes a surgical case of basilar-superior cerebellar (BA-SCA) junction aneurysm and posterior cerebral artery (PCA) aneurysm associated with moyamoya disease. A-38-year-old man in an unconsciousness state and with mild left hemiparesis was referred to our hospital. CT scan demonstrated hemorrhage in the right basal ganglia. Carotid angiograms showed stenoses at the terminal portion of the bilateral internal carotid arteries and moyamoya vessels. Left vertebral angiograms showed two aneurysms at the junction of the right superior cerebellar artery and the basilar artery and at the P1 portion of the left posterior cerebral artery. Two aneurysms were successfully clipped using the pterional approach. Bilateral encephaloduroarteriosynangiosis (EDAS) was also performed for the treatment of Moyamoya disease. Postoperative angiograms revealed complete clipping of the aneurysms and the postoperative course was uneventful.

Anaplastic large cell lymphomas expressing the novel chimeric protein p80NPM/ALK: a distinct clinicopathologic entity

Anaplastic large cell lymphoma (ALCL) is a subtype of non-Hodgkin's lymphoma characterized by the CD30+ large neoplastic cells and sometimes carries a t(2;5)(p23;q35). Recently, we found a novel hyperphosphorylated 80-kD protein tyrosine kinase, p80, in ALCLs with t(2;5). Subsequent cDNA cloning showed p80 to be a fusion protein of two genes, the novel tyrosine kinase gene and the nucleophosmin gene, in accordance with the sequence of the NPM/ALK gene (Morris et al, Science 263:1281, 1994). Meanwhile, the clinicopathologic features of p80-carrying ALCLs have remained unclear. Paraffin sections of 105 cases of ALCL were immunostained using anti-p80 antibody, and 30 of them were shown to express p80. Clinicopathologic comparison between p80-positive and -negative ALCLs showed that p80-positive cases occurred in a far younger patient age group (16.2 +/- 12.9 years; p80-negative cases, 51.0 +/- 22.3 years; P < .0001) and the patients showed a far better 5-year survival rate (79.8%; p80-negative group, 32.9%; P < .01). These data showed that p80-positive ALCL is a distinct entity both clinically and pathogenetically and should be differentiated from p80-negative ALCL.

Promoting effects of phenobarbital on the enzyme-altered foci induced by intrahepatic gamma-ray-irradiation in the rat liver

Radiation-induced carcinogenesis of the rat liver using iridium-192 seeds as an intrahepatic radioactive source was studied by enzyme histochemical means. Rats were divided into six groups according to various combinations of one or two iridium-192 or stainless steel seeds and whether they were given a diet containing 0.05% phenobarbital (PB) or a basal diet (BD). Each group were sacrificed at 20, 40, and 60 weeks after intrahepatic insertion of the iridium-192 or stainless steel seeds. gamma-Glutamyl transpeptidase (GGT), glucose-6-phosphatase (G6Pase), and adenosine triphosphatase (ATPase) were stained in the liver tissues, and GGT-positive foci were quantified. Liver neoplasm was not evident, but enzyme-altered foci (EAF) were induced by gamma-ray irradiation. At every point (20, 40, and 60 weeks) after the insertion of the seeds, the GGT-positive area was larger in the rats given than those given BD. Moreover, despite the iridium-192 radioactivity decay, EAF developed continuously in the rats given PB, and persisted in those given BD from 40 to 60 weeks after insertion. These results indicated that phenobarbital promotes the development of EAF initiated by irradiation, as it promotes the process of chemical carcinogenesis in the rat liver.

Flow cytometric analysis of DNA synthetic phase fraction of the normal appearing colonic mucosa in patients with colorectal neoplasms

DNA synthetic (S) phase fractions of normal appearing colonic mucosa in Japanese and British patients with colorectal neoplasms were compared with those in patients without colonic neoplasms. Normal crypts were isolated from fresh surgical specimens of the large intestine by the use of EDTA. After fixation with 70% ethanol, isolated crypts were digested with pepsin into single nuclei suspensions. These were stained with propidium iodide and examined by flow cytometry. S phase fraction was calculated from the flow cytometry DNA histogram using Baisch's method. S phase fractions of normal appearing crypts in Japanese and British patients with colorectal tumours were not significantly different and analysed together. S phase fraction of normal appearing colonic crypts in 14 patients with familial adenomatous polyposis (FAP) was 10.23 (2.59%) (mean SD)) ranging from 5.8 to 18.8. S phase fraction of background normal mucosal in patients with large adenomas (over 2 cm) and adenocarcinomas were 9.74 (3.76%) (range, 2.7-16.1) and 8.93 (3.54%) (range, 2.9-18.9) respectively. In normal mucosa of patients without any colorectal neoplasms, S phase fraction was 8.99 (3.94)% (range, 3.9-17.7). There was no statistically significant difference in S phase fractions of normal mucosa in the four groups. Our results show that an increase in proliferative activity of background colonic crypts is not necessary for tumour development.

Poorly differentiated ('insular') carcinoma of the thyroid

Three cases of unusual poorly differentiated ('insular') carcinoma of the thyroid gland are presented. These three thyroid carcinomas were large; the tumors from patients 1 and 3 were encapsulated, and that from patient 2 showed invasive growth. Microscopically the tumors were characterized by well-defined solid nests (insulae), which were composed of rather small and uniform tumor cells with round to oval nuclei. Formation of small and colloid-containing follicles was associated with these nests to varying degrees. The tumors of patients 1 and 3 were composed entirely of insular components, but that of patient 2 was associated with small areas of well-differentiated follicular carcinoma. The metastatic tumors of patients 1 and 2 were essentially similar to the primary with small foci of follicular carcinoma. Patient 1 is alive with local and mediastinal node recurrences, but patient 2 died of the disease with local recurrences and metastases to lungs, bones and skin. Patient 3 had no recurrences and died of unrelated disease 5 years after surgery. The present study indicates that insular carcinomas have characteristic histologic features and a less favorable prognosis, confirming the findings of previous studies.

Spatial learning impairment in aged rats: comparing between aged basal forebrain lesioned and normal aged rats

Normal aged rats (26 months) displayed significant impairments in learning the Morris water maze task as compared with young adult rats (3 months). The learning deficits of aged basal forebrain (BF)-lesioned rats (26 months; ethylcholine aziridinium ion was injected into the bilateral basal forebrain at 3 months age) were more severe than those of normal aged rats. Choline acetyltransferase (ChAT) in the frontal cortex of aged BF-lesioned rats activity was significantly reduced, but not in normal aged rats which level was almost the same as that in young adult rats. Histological examination showed that cholinergic fibers (acetylcholinesterase staining) in the frontal cortex reduced in aged BF-lesioned rats, but not in normal aged rats. The number of binding sites (Bmax) for [3H]vesamicol, a ligand for the vesicular acetylcholine transporter, in the frontal cortex of normal aged rats was significantly less than that in young adult rats, while the Bmax of aged BF-lesioned rats was higher than that of normal aged rats. The levels of monoamines and their metabolites in the frontal cortex and striatum but not hippocampus of aged BF-lesioned rats were markedly reduced as compared with those of normal aged and young adult rats. These results taken together indicate that normal aged and aged BF-lesioned rats exhibit learning deficits and that the differences of the severity of spatial learning deficits between normal aged and aged BF-lesioned rats may be due to, at least in part, the different properties of cathecolaminergic, serotonergic and cholinergic dysfunctions in the discrete brain sites.

Antagonizing effects of VA-045 on reduced activity of rat locus coeruleus neurons following head injury or intravenous injection of clonidine

Based on the finding that VA-045, a novel apovincaminic acid derivative, had improved disturbance in consciousness, we examined the effects of the drug on the electrical activity of locus coeruleus (LC) neurons in animal models of consciousness disturbance. The animal models of consciousness disturbance used in this experiment were closed head injury (CHI) and intravenous injection of clonidine. CHI as well as clonidine injection reduced the spontaneous activity of LC neurons. The reduction of the spontaneus activity of LC neurons following CHI or clonidine injection was restored by intravenous injection of VA-045. The change of LC neuronal activity induced VA-045 preceded desynchronization of EEG. These results suggest that VA-045 exerts its ameliorating effect on consciousness disturbances, at least in part, by augmenting the spontaneous activity of noradrenergic LC neurons.

[Age-related changes in amplitude ratio, duration ratio and area ratio in nerve conduction studies]

We investigated the effect of aging on nerve conduction parameters in 184 subjects (aged 10-75 years) without any history or signs of peripheral neuropathy, in order to clarify the diagnostic parameters of demyelinating neuropathies in the aged. The CMAP amplitude ratio (proximal CMAP/distal CMAP), duration ratio and area ratio remained unchanged throughout the second to eighth decades. The lower limits of normal CMAP amplitude ratio (mean -3SD) were 0.79 (median nerve), 0.74 (ulnar nerve), 0.59 (peroneal nerve), and 0.48 (tibial nerve). The upper limits of normal CMAP duration ratio (mean 11+ 3SD) were 1.22 (median nerve), 1.19 (ulnar nerve), 1.35 (peroneal nerve), and 1.32 (tibial nerve). The lower limits of normal CMAP area ratio (mean -3SD) were 0.84 (median nerve), 0.78 (ulnar nerve), 0.61 (peroneal nerve), and 0.62 (tibial nerve). There were no age-related changes in amplitude ratio or duration ratio of SNAP, although the standard deviations increased with age. Since the amplitude ratio, duration ratio and area ratio are simple and age-independent, they can provide useful and reliable information for routine nerve conduction studies for aged patients with demyelinating neuropathies.

Optic neuritis in cerebral toxocariasis

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