Oblique sagittal magnetic resonance imaging visualizing vascular compression of the trigeminal or facial nerve

An oblique sagittal magnetic resonance (MR) imaging method was developed to provide better visualization of vascular compression of nerves. The MR images of 12 patients with trigeminal neuralgia and 24 with hemifacial spasm were analyzed. The oblique sagittal views were obtained along the nerve identified by the axial view at an angle of 105 degrees between the line along the dorsal brain stem and the line along the margin of the pontomedullary junction (in patients with hemifacial spasm) or by the midsagittal view through the midpons (in patients with trigeminal neuralgia). The T1- and T2-weighted, proton-density, and/or gradient-echo MR images were evaluated to optimize imaging conditions. The oblique sagittal gradient-echo MR image most clearly visualized vascular compression of the nerves as high-intensity lines in six patients with trigeminal neuralgia, which was confirmed intraoperatively in four. Fifteen (75%) of 20 oblique sagittal gradient-echo MR images demonstrated vascular compression of the facial nerves in patients with hemifacial spasm; 12 of these were confirmed intraoperatively. The control study used 15 oblique sagittal gradient-echo MR images of nonaffected contralateral and normal sites. Four false-positive findings were found. Oblique sagittal gradient-echo MR images are a useful planning aid, allowing differential diagnosis prior to microvascular decompression in trigeminal neuralgia and hemifacial spasm.

Giant aneurysm of the azygos anterior cerebral artery associated with acute subdural hematoma--case report

A ruptured giant aneurysm of the azygos anterior cerebral artery (ACA) associated with an acute subdural hematoma (SDH) occurred in a 67-year-old male with two episodes of sudden severe headache and transient loss of consciousness. Neurologically, he had mild weakness of the left lower extremity. Computed tomography showed an elliptical heterogeneous hyperdense mass in the interhemispheric fissure in front of the corpus callosum and an acute SDH on the right. Angiography disclosed a giant aneurysm (2.8 x 2.0 cm) at the distal end of the azygos ACA. Removal of the SDH and aneurysmal neck clipping achieved a good outcome. Successive small bleedings may allow the aneurysmal dome to develop adhesions to the arachnoid membrane, and the final rupture will occur into the subdural space, resulting in a SDH.

Inhibitory effect of human fibroblast interferon (HuIFN-beta) on the growth and invasive potential of cultured human melanoma cells in vitro

The effect of HuIFN-beta on the invasive potential of melanoma cells was studied using an in-vitro model system with Transwell chambers equipped with matrigel-coated polycarbonate filters. When (10(2), 10(3) and 10(4) IU/ml) for 3 days and then grown in medium without HuIFN-beta for another 7 days. On day 7, the proliferation of melanoma cells was inhibited by 77 and 87%, respectively, when cells were treated with 10(2) and 10(4) IU/ml of HuIFN-beta. This antiproliferative effect was dose-dependent and more pronounced on day 11. The effect of HuIFN-beta on the invasive potential of melanoma cells was studied using an in-vitro model system with Transwell chambers equipped with Matrigel-coated polycarbonate filters. When cells were treated with HuIFN-beta (10(2), 10(3) and 10(4) IU/ml) for 24 h, the amount of tritiated thymidine incorporated into cells was increased, indicating that cell growth was not inhibited. However, the number of cells that invaded to the filter decreased significantly by 15-40%. HuIFN-beta did not have an inhibitory effect on the haptotactic migration of melanoma cells. These data indicate that the antiproliferative effect of HuIFN-beta occurs after 24 h and that the direct anti-invasive effect is independent of any effect on proliferation.

Detection of point mutations in human DNA by analysis of RNA conformation polymorphism(s)

RNA molecules were found to separate into numerous metastable conformational forms upon non-denaturing gel electrophoresis. The equilibration of the conformations was accelerated by heating or mild denaturing conditions. Single-base substitutions in the sequence of the RNAs caused changes in the conformational patterns, including mobility shifts of major and minor conformations, appearance of new conformations and loss of other conformations. This sequence-dependent RNA conformational polymorphism was used to detect point mutations in p53 and, dihydrofolate reductase genes. Sense and anti-sense RNA strands corresponding to the same segment of the p53 gene gave entirely different conformational patterns. To generate the RNA, short regions of the target genes (up to about 250 bp) were amplified by the polymerase chain reaction and the resulting DNA segments transcribed to RNA by T7 RNA polymerase. The method is rapid, simple, amenable to non-radioactive visualization and was successful in several cases when DNA single-strand conformational polymorphism analysis (Orita et al. (1989) Genomics 5, 874-879) failed to detect the point mutation.

Partial resection of the gyrus rectus in pterional approach to anterior communicating artery aneurysms

The effect of partial resection of the gyrus rectus during the unilateral pterional approach on surgical outcome was evaluated in 194 consecutive patients with ruptured anterior communicating artery aneurysms. Resection was performed more frequently in cases with poor clinical grade, in the acute stage, with superiorly directed aneurysms, and with high-positioned aneurysms. The surgical results were graded into three stages, and the follow-up results into five stages using the Glasgow Outcome Scale. Outcomes for 52 patients receiving gyrus rectus resection were compared with those for 142 patients without resection. There were no apparent effects caused by gyrus rectus resection on outcome.

NAD(P)H:quinone oxidoreductase gene expression in human colon carcinoma cells: characterization of a mutation which modulates DT-diaphorase activity and mitomycin sensitivity

NAD(P)H:quinone oxidoreductase (DT-diaphorase; DTD) is an obligate two-electron reductase which may play a role in the bioactivation of antitumor quinones such as mitomycin C (MMC). We studied 10 colon carcinoma cell lines showing different levels of DTD activity (range, 0-3447 nmol/min/mg protein), as measured by the reduction of dichlorophenolindophenol. Expression of the NAD(P)H:quinone reductase gene (NQO1), which codes for the DTD enzyme, as measured by a polymerase chain reaction amplification technique was then correlated with enzymatic activity in all cell lines. HT-29 cells, which have intermediate DTD activity (769 +/- 144 nmol/min/mg protein, mean +/- SD) and are sensitive to MMC, showed high NQO1 expression relative to beta-actin (taken as 100% here for comparative purposes). BE cells which have no detectable DTD activity and are resistant to MMC showed moderate NQO1 expression (91% of HT-29). RNA single-strand conformational polymorphism analysis and subsequent sequencing of BE complementary DNA revealed a C to T mutation in the NQO1 complementary DNA. This confers a proline to serine substitution in the amino acid sequence of the protein. Additionally, HCT-116 cells showed both moderate DTD activity (390 +/- 41 nmol/min/mg protein) and NQO1 expression (41% of HT-29), while resistant subclones of these cells, exposed to MMC during 11 and 44 weeks, showed low gene expression (5 and 9% of HT-29 respectively) and enzymatic activity (11 +/- 6 and 36 +/- 16 nmol/min/mg protein). These results support the ideas that reductive activation of MMC by DTD may be important in the cytotoxicity of MMC and that polymerase chain reaction may be a useful technique for quantitating the relative expression of genes in human tumors.

Quantitation of thymidylate synthase, dihydrofolate reductase, and DT-diaphorase gene expression in human tumors using the polymerase chain reaction

A polymerase chain reaction (PCR)-based method was used to quantitate the expression levels of low abundance genes relevant to cancer drug activity. RNA from tumor samples as small as 20 mg was isolated and converted to cDNA using random hexamers. The 5' primers for the PCR contained a T7 polymerase promoter sequence, allowing the PCR-amplified DNA to be transcribed to RNA fragments. In each sample, the linear ranges of amplification of each cDNA of interest were established. Relative gene expressions were calculated by extrapolating the amounts of PCR products generated within the linear amplification regions of each gene to equal volumes of the cDNA solution. The method was accurate to less than a 2-fold difference in expression levels. Using beta 2-microglobulin and beta-actin gene expressions as internal reference standards and cDNA from HT-29 cells as an external linearity standard, we measured the relative expressions of thymidylate synthase, dihydrofolate reductase, and DT-diaphorase in a number of clinical tumor samples. The expressions of these genes varied from 50- to 100-fold among different tumors, although most of the values were grouped within about a 10-fold range. The amount of thymidylate synthase gene expression in tumor tissues was directly proportional to the content of thymidylate synthase protein. Those tumors with the lowest thymidylate synthase expression had the best response to both the 5-fluorouracil-leucovorin and 5-fluorouracil-cisplatin combinations.

[Clinical effect of proton pump inhibitors on reflux esophagitis]

The clinical efficacy of proton pump inhibitors (PPI, omeprazole 20 mg or lansoprazole 30 mg), once daily, after breakfast, was studied in patients with erosive/ulcerative reflux esophagitis. The following results were obtained. 1) Twenty-four hour esophageal pH monitoring was performed before treatment and on 7th day of PPI medications. Omeprazole reduced the percent time pH less than 4 from 29.1 to 1.2 and lansoprazole from 68.0 to 2.4. 2) The cumulative disappearance rate of overall symptom was 52% after 1 week and 62% after 2 weeks with omeprazole these were 66% and 91%, and with lansoprazole respectively 3) The endoscopic healing rate was 63% was after 2 weeks and 76% after 4 weeks with omeprazole medication, and 76% and 97% respectively with lansoprazole. These results indicate that PPI medication inhibits the acid reflux almost completely and is a more useful therapeutic agent for GERD than H2-antagonists.

Oral passive immunization against dental caries in rats by use of hen egg yolk antibodies specific for cell-associated glucosyltransferase of Streptococcus mutans

The effect of polyclonal egg yolk immunoglobulin G antibodies (yIgG) raised against whole cells, cell-free (CF) glucosyltransferase (GTase), or cell-associated (CA) GTase of serotype c Streptococcus mutans was examined in terms of in vitro inhibition of virulence-related factors of S. mutans and protection of S. mutans-infected rats against the development of dental caries. Hens (18 weeks old) were immunized with formalin-treated whole cells, purified CF-GTase, or CA-GTase together with Freund's complete adjuvant. In addition, yIgG to surface protein antigen was used in some in vitro experiments for comparison with other antibodies. yIgG was purified by ammonium sulfate precipitation followed by DEAE-Sephacel column chromatography or fractional precipitation with ethanol. Purified yIgG was found to be a 220-kDa protein, which was dissociated into heavy and light chains upon addition of 2-mercaptoethanol. yIgG to whole cells and surface protein antigen gave a heavy aggregation of S. mutans organisms, while yIgG to CF- and CA-GTase specifically inhibited the enzymatic activity of the respective GTase. yIgG to CA-GTase and whole cells was found to clearly suppress the adherence of S. mutans cells to a glass surface. Specific-pathogen-free Sprague-Dawley rats that had been infected heavily and repeatedly with S. mutans and fed diet no. 2000 developed severe dental caries, while rats fed diet 2000 containing greater than or equal to 0.1% yIgG to CA-GTase showed a statistically significant reduction in dental plaque accumulation and caries development. Administration of yIgG to CF-GTase and whole cells failed to protect against caries. These results clearly suggest that yIgG to S. mutants CA-GTase specifically inhibited a virulence factor of this organism, i.e., insoluble glucan-synthesizing CA-GTase, resulting in a significant reduction in the development of dental caries.

Developmental assembly of calcium-mobilizing systems for excitatory amino acids in rat cerebellum

The postnatal development of calcium-mobilizing systems was studied by both microfluorometric imaging analysis of Ca2+ on living rat cerebellar slices and immunohistochemical labeling of phosphatidylinositol 4,5-bisphosphate (PIP2) and inositol 1,4,5-trisphosphate binding protein (IP3BP) in fixed rat cerebellum. Stimulation with quisqualate (QA) or N-methyl-D-aspartate (NMDA) enhanced the Ca2+ level only diffusely on postnatal day (PND) 3, but more discretely on PNDs 7 and 15. On PND 21, QA-induced responses were localized in the molecular layer especially, but not in the granular layer. By contrast, NMDA mobilized Ca2+ prominently in the granular layer, but only weakly in the molecular layer. Localized expression of PIP2 in the molecular layer paralleled QA-induced Ca2+ mobilization, but IP3BP was expressed more diffusely. The present study offers the first direct evidence that PIP2, but not IP3BP, is essential for QA-induced Ca2+ mobilization in the cerebellar cortex.

Inactivation of Tetrahymena rRNA self-splicing by cis-platin proceeds through dissociable complexes

The anti-cancer drug cis-diamminedichloroplatinum (II) (cis-DDP) reacted with Tetrahymena self-splicing rRNA ribozyme, causing loss of self-splicing activity and formation of a number of platinated RNA species. The formation of one distinct platinated product, migrating at an apparent size of 2400 nt, was closely associated with ribozyme inactivation. This platinated RNA was resistant to T1 ribonuclease digestion, suggesting the presence of inter-strand Pt cross-links. The reaction rate of cis-DDP with the ribozyme followed first order kinetics and showed a saturation effect with increasing cis-DDP concentration, characteristic of an affinity-label type of interaction rather than bimolecular collision. The apparent KI for binding of cis-DDP to the ribozyme was 62 microM. Ribozyme treated with urea was not inactivated by cis-DDP, indicating that the native structure of the RNA is required for reaction with cis-DDP. Mg++, which binds to the ribozyme and causes conformational changes in the molecule, protected the ribozyme from inactivation by cis-DDP and also prevented the formation of platinated RNA. These results suggest that binding of cis-DDP to sites formed by certain secondary or tertiary structural elements of the RNA enhance the rate and the specificity of reaction of the reagent with the ribozyme.

Effects of oxygen tension on the growth and pigmentation of normal human melanocytes

The effects of oxygen tension on human melanocyte growth, tyrosinase activity, and melanin production were assessed. Melanocytes, seeded at 10(4) cells/cm2, were grown in modified Eagle's medium (MEM) with 5% fetal bovine serum (FBS) and 10 ng/ml 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Flasks were equilibrated with gas mixtures containing 5% CO2 and various partial pressures of oxygen (PO2 7-620 mm Hg) and kept in incubators, which were electronically maintained at the desired oxygen tensions. Melanocytes grew best at PO2 from 6-34 mm Hg. Growth was reduced by 30% at PO2 142 mm Hg, and even more at O2 tensions greater than 230 mm Hg. A PO2 of 603 mm Hg was cytotoxic. Tyrosinase activity (assayed by the method of Pomerantz) was 300 microU/mg protein at PO2 7-34 mm Hg. At PO2 235 and 355 mm Hg tyrosinase activity decreased to about 100 microU/mg protein. The apparent Km for tyrosine was unchanged in melanocytes cultured at all experimental oxygen tensions. The Vmax, however, was decreased at the higher oxygen tensions (PO2 235 mm Hg). At PO2 6-135 mm Hg the melanin content was proportional to tyrosinase activity. At cytostatic oxygen tensions (PO2 235 and 355 mm Hg) the intracellular melanin content increased somewhat, although tyrosinase activity was decreased. Low oxygen tension is favorable for both melanocyte proliferation and tyrosinase activity.

Normal values of urinary excretion and serum concentration of 5-S-cysteinyldopa and 6-hydroxy-5-methoxyindole-2-carboxylic acid, biochemical markers of melanoma progression

The urinary excretion of the pheomelanin precursor 5-S-cysteinyldopa (5-S-CD) has been used as a tumour marker for metastatic melanoma. The eumelanin-related metabolite 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5M12C) is also excreted at high levels in some melanoma patients. In order to compare normal values, we measured urinary excretion and serum concentration of 5-S-CD and 6H5M12C in 33 Japanese normal subjects. The mean values of 5-S-CD and 6H5M12C in urine were 0.45 and 0.39 mumol/day, respectively, and those in serum 4.3 and 3.6 nmol/l. Levels of these markers in urine were much more variable than those in serum. We have adopted 1.5 mumol/day and 10 nmol/l as the upper limits for normal ranges of the urinary excretion and serum concentration, for both markers. No significant differences were found between men and women. There were no correlations among the four markers. The urinary excretion of both markers showed significant decrease in elderly subjects as compared with middle-aged subjects, while the serum concentration showed no age-dependent differences. These results suggest that the levels of 5-S-CD and 6H5M12C in serum are more reliable as tumour markers for the estimation of melanoma progression than those in urine.

[Interdigestive migrating complex (IMC) and effect of cisapride in patients with non-ulcer dyspepsia (NUD)]

The 24-hr gastric and duodenal pressure measurement was performed in 5 patients with non-ulcer dyspepsia (NUD). The reduction of incidence of IMC and prolongation of the first appearance of IMC after evening meal were observed in NUD patients. The gastroprokinetic agent, cisapride 5 mg, 3 times a day for 7 days significantly increased the incidence of IMC and shortened the time before the first appearance of IMC after evening meal. This result indicates that in NUD patients impaired gastrointestinal motility is present in fasting phases and cisapride may be useful for correcting motility disorders.

Comparative efficacy of acid reflux inhibition by drug therapy in reflux esophagitis

The advent of histamine H2 receptor antagonists (H2-RA) has allowed the treatment of reflux esophagitis (RE) to be controlled over a relatively long term. The authors have experienced some cases resistant to H2-RA, but it was revealed that these cases can be successfully treated with proton pump inhibitors. It has been suggested that esophagogastric dysmotility can lead to RE. RE has been treated for many years by using GI-prokinetic agents, which theoretically inhibit acid reflux and improve esophageal acid clearance. In order to compare the effects on acid reflux of an H2-RA (famotidine), a proton pump inhibitor (omeprazole) and a GI-prokinetic agent (cisapride), we measured the 24-hour pH in the esophagus and stomach simultaneously, before and after treatment in 17 patients with RE. It was found that the proton pump inhibitor was the most effective drug for inhibiting esophageal acidification, followed by famotidine and then cisapride. Furthermore, we found that cisapride often actually exacerbated acid reflux. The differences in inhibitory effects on acidification allowed us to draw conclusions regarding the treatment of RE. It was concluded that the stronger the inhibitory effect of a drug on acid secretion, the more useful it was in the treatment of RE. The GI-prokinetic drug did not inhibit acid reflux as much as we had expected.

Effects of famotidine on upper gastrointestinal motility in patients with progressive systemic sclerosis

The effects of famotidine on human upper gastrointestinal motility were investigated, together with the relationship of gastric alkalinization and serum gastrin levels to changes produced by famotidine. Intravenous famotidine (20 mg), at a dose level in which an inhibitory effect on acetylcholinesterase activity is not recognized, was given to 13 patients with progressive systemic sclerosis but no other disorders. Gastric phasic motor activity was not changed significantly, but the lower esophageal sphincter pressure was elevated significantly in comparison with 15 controls given physiological saline, even when gastric phasic motor activity was taken into consideration. Gastric alkalinization with 7% sodium bicarbonate did not significantly increase the sphincter pressure in all 7 subjects so treated. No significant correlation was recognized between the serum gastrin level, the lower esophageal sphincter pressure, and the gastric motility index in any of the 3 groups. It was, therefore, concluded that intravenous administration of famotidine affected upper gastrointestinal motility, especially the lower esophageal sphincter pressure, through an as yet unknown mechanism other than inhibition of acetylcholinesterase activity, gastric alkalinization, or elevation of serum gastrin levels.

The relationship between interdigestive gallbladder and gastroduodenal motility in man

The relationship between interdigestive gallbladder and gastroduodenal motility simultaneously with the behavior of plasma motilin and CCK levels in 20 subjects was investigated. We used an infusion catheter method for the measurement of gastroduodenal motility, and real-time ultrasonography for the measurement of gallbladder size. In gastric phase II, the gallbladder contracted with extension of the major axis and shrinking of the minor axis, with its minimum volume being 84% of the volume in phase I. The gallbladder then filled rapidly assuming a sphere-like shape with extension of the minor axis and shrinking of the major axis in gastric phase I. This motility was recognized only during the gastrointestinal interdigestive migrating complex (GI-IMC) cycle, originating in the stomach, and was associated with an increase of motilin levels, it was not seen before or after the intestinal IMC (I-IMC), which originated in the duodenum without contraction of the stomach or an increase of motilin levels. Furthermore no apparent relationship was recognized between CCK and gastric or gallbladder motility. Our findings suggest that gallbladder motility in the interdigestive period has a close relationship with gastroduodenal motility and is related to the appearance of the GI-IMC.

Regional distribution of metabotropic glutamate response in the rat brain using Xenopus oocytes

The regional distribution of metabotropic L-glutamate responses was investigated in Xenopus oocytes injected with poly(A)+-RNA from a rat brain which was separated into 3 parts: cerebrum, cerebellum and brainstem. Under voltage-clamp, oscillatory current responses were induced more in cerebellum or brainstem poly (A)+-RNA-injected oocytes, and less in cerebrum poly(A)+-RNA-injected oocytes. These results suggest that the metabotropic glutamate receptor is distributed mostly in cerebellum and brainstem.

Merkel cell carcinoma. A successful treatment with tumor necrosis factor

A Merkel cell carcinoma of the mandibular area in a 78-year-old woman was treated successfully by direct intratumoral administration of recombinant human tumor necrosis factor. The patient received 2.5 x 10(5) U/d of recombinant human tumor necrosis factor every other day. A total of six injections (total dose, 1.5 x 10(6) U, 0.52 mg of protein) were administered over a period of 12 days. Soon after the therapy ended, the lesion softened and decreased in size. After 1 month, only erythema was visible. The lesion had completely disappeared clinically and histologically 5 months after the local injection of recombinant human tumor necrosis factor. Neither recurrence nor metastasis has been observed for at least 12 months following the treatment. Recombinant human tumor necrosis factor is suggested to be effective for the treatment of Merkel cell carcinoma.

Fine structural and immunohistochemical properties of dysplastic melanocytic nevi: comparison with malignant melanoma

This study will review the clinical features of dysplastic melanocytic nevi (DMN) in Japanese cases, and then show the fine structure of melanosomes/melanogenesis in the dysplastic melanocytes and the immunohistochemical property of DMN as identified by monoclonal antibodies against human melanosome specific antigen (HMSA). The incidence of DMN is quite low in the Japanese. It is indicated that this fact may partly explain the low incidence of malignant melanoma in Japanese; in particular, low incidence in sun-exposed areas. The patients with DMN were largely males. They were different from ordinary Japanese in that they usually burn and tan poorly after sun exposure. In addition, the synthesis of melanosomes in the dysplastic melanocytes was found to be abnormal and characterized by a significant alteration in the fine structure of the melanosomal matrix and the pattern of melanization. These abnormal melanosomes reacted positively with MoAb HMSA-1 and HMSA-2, which identify the structural matrix protein of melanosomes unique to neoplastic melanocytes. Importantly, HMSA was present in both dysplastic melanocytes and melanoma cells, but not in epidermal melanocytes (nevus cells) of common melanocytic nevi.

Purification and characterization of cell-associated glucosyltransferase synthesizing water-insoluble glucan from serotype c Streptococcus mutans

Strains of Streptococcus mutans (serotypes c, e and f) were found to possess high levels of glucosyltransferase (GTase) activity, both cell-associated and in the culture medium, when grown in either sucrose-free or sucrose-containing broth media. The cell-associated GTase of S. mutans MT8148 (serotype c) was effectively extracted by treatment with 8 M-urea at 25 degrees C for 1 h. Approximately 95% of the GTase activity was solubilized by this treatment. The crude extract was purified by DEAE-Sephacel and hydroxylapatite column chromatography. For comparison, extracellular GTase was also purified from the culture supernatant of the same strain by ammonium sulphate precipitation, chromatofocusing and hydroxylapatite chromatography. The molecular masses of the cell-associated and extracellular GTase proteins were similar (156 kDa) as determined by SDS-PAGE. However, the pH optima for maximum GTase activity were different: pH 6.7 to 7.0 for the cell-associated enzyme and pH 5.5 to 6.5 for the extracellular enzyme. The product of cell-associated GTase from sucrose was almost exclusively water-insoluble glucan. On the other hand, extracellular GTase produced mainly water-soluble glucan from sucrose. This indicates that GTase synthesizing water-insoluble glucan is present primarily in a cell-associated form in serotype c S. mutans. Insoluble glucan synthesis by the cell-associated GTase from sucrose was not enhanced by addition of primer dextran T10 to the reaction mixture. The extracellular and cell-associated GTases were immunologically unrelated as determined by ELISA using monoclonal antibodies.

Taurine modulates glycine response in Xenopus oocytes injected with messenger RNA from mouse brain

The modulatory action of taurine on the glycine response was investigated in Xenopus oocytes injected with messenger RNA from mouse brainstem under voltage-clamped condition. Taurine competitively inhibited the glycine response in a dose-dependent manner. This inhibition was insensitive to bicuculline and intracellularly injected EGTA. The results suggest that taurine could directly modulate glycinergic neurotransmission in the central nervous system.

Production and characterization of monoclonal antibodies that bind to phosphatidylinositol 4,5-bisphosphate

We established a series of monoclonal antibodies (MAbs) that bound to phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] which is confidently believed to play an important role in cellular signal transduction. We used complement dependent liposome lysis assay for screening MAbs and antibodies that bind to PI(4,5)P2 but not to phosphatidylinositol 4-monophosphate [PI(4)P] were selected. The reactivity of the MAbs was analyzed by complement dependent liposome lysis assay, enzyme-linked immunosorbent assay (ELISA) and inhibition of liposome lysis by soluble haptens. The MAbs exhibited three distinct reactivity profiles measured by three different assay systems and the results obtained from three typical MAbs designated AM-2, AM-7 and AM-212 are described. On liposome lysis assay, all three MAbs were highly specific with PI(4,5)P2 and no cross-reaction with other acidic phospholipids such as PI(4)P, phosphatidylinositol (PI), phosphatidic acid (PA), phosphatidylserine (PS), phosphatidylethanolamine (PE) and cardiolipin (CL) was observed. All three MAbs were able to react with as low as 0.1 mol% of PI(4,5)P2 embedded in the liposomal membrane. On ELISA, AM-2 and AM-212 bound only to PI(4,5)P2 and did not cross-react with other acidic phospholipids including PI(4)P. In contrast, AM-7 showed considerable binding to other phospholipids such as PI(4)P, PA and PE on ELISA. The reactivities of the MAbs with water soluble haptens such as inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] were examined by inhibition of liposome lysis. Among three clones examined, only AM-212 showed considerable reactivity with Ins(1,4,5)P3 while also showing weak cross-reactivity with fructose 1,6-diphosphate and inositol 1,4-bisphosphate. No cross-reaction with other structural analogs such as inositol 1-monophosphate and inositol 2-monophosphate was observed.

Taurine and beta-alanine act on both GABA and glycine receptors in Xenopus oocyte injected with mouse brain messenger RNA

The responding pathway (process from agonist binding to channel opening) of taurine and beta-alanine was investigated in Xenopus oocytes injected with mouse brain poly(A)+ RNA. Responses to gamma-aminobutyric acid (GABA), glycine, taurine and beta-alanine were induced in oocytes injected with poly(A)+ RNA extracted from 3 regions, cerebrum, cerebellum and brainstem of the mouse brain. From comparison, responses to these 4 inhibitory amino acids in each regional poly(A)+ RNA-injected oocytes were categorized into at least 3 groups: (1) GABA, (2) glycine, and (3) taurine and beta-alanine. No cross-desensitization was observed between GABA response and glycine response, but taurine and beta-alanine responses cross-desensitized both the GABA and glycine responses. Taurine and beta-alanine responses were partially inhibited by the GABA antagonist, bicuculline, and also by the glycine antagonist, strychnine. The results suggest that the taurine or the beta-alanine response in the brain is caused through both the GABA receptor and the glycine receptor.

Effects of panose on glucan synthesis and cellular adherence by Streptococcus mutans

The effects of panose on glucan synthesis and sucrose-dependent cellular adherence by Streptococcus mutans were investigated. Panose effectively inhibited glucan synthesis from sucrose by glucosyltransferases from S. mutans strain 6715, but increasing amounts of panose increased the release of fructose from sucrose by the enzymes. On the other hand, production of a series of oligosaccharides of increasing size by the enzymes was markedly enhanced in the presence of panose. These results indicate that panose activates the enzymes and that the inhibition of glucan synthesis by panose is due to the transfer of the glucosyl group of sucrose to panose. Sucrose-dependent adherence of cells of various S. mutans strains to a glass surface was also inhibited by panose.

Fluorescent dye monitoring of mitochondrial changes associated with malignant cell transformation

The fluorescent dyes, rhodamine 6G and 123, which specifically stain mitochondria, were used to examine changes in mitochondria that follow malignant transformation. The spatial distribution and shapes of mitochondria differ in untransformed and malignant-transformed cells. In untransformed C3H/10T1/2 clone 8 cells, the mitochondria were distributed radially around the nucleus, and each had a fibrous shape. In chemically transformed MCA clone 16 cells, the mitochondria were distributed randomly in the cytoplasm, and each was shaped like a short rod. Another important mitochondrial change after malignant transformation was the change in the time course of fluorescence emission from the rhodamine present in the mitochondria. A slow increase in fluorescence, which was instantaneous at the time of excitation irradiation occurred in untransformed but not in transformed cells. This slow fluorescence emission, peculiar to untransformed cells was affected by proton ionophore but not by calcium ionophore treatment. The difference in the time courses of fluorescence emission for untransformed and transformed cells may reflect differences in the quenching of the dye fluorescence. The data reported provide evidence that mitochondria are affected by malignant cell transformation.

Symmetrical bilateral low-density lesions in the areas of supply by Heubner's arteries after aneurysm surgery

Three patients with symmetrical bilateral low-density areas which were the perfusion territories of Heubner's arteries are reported. The infarctions were demonstrated on computed tomography after aneurysm surgery. Two of them had an anterior communicating artery aneurysm and the other one had multiple aneurysms of both sides. They were operated upon in the acute stage after subarachnoid haemorrhage. As common factors, a thick and diffuse subarachnoid haemorrhage, an acute-stage operation, temporary clips to bilateral A1 segments or the internal carotid artery and a relatively low systemic blood pressure during operation were found. From these findings we conclude that the pathogenesis of the infarctions was due to occlusive changes affecting Heubner's arteries bilaterally.

The cytochrome P-450-dependent hydroxylation of T-2 toxin in various animal species

Gas-liquid chromatography was used to investigate the hepatic and intestinal metabolism of T-2 toxin, a cytotoxic and immunodepressive trichothecene produced by species of Fusarium. The hepatic S-9 and microsomal fractions of various species hydroxylated T-2 toxin to form 3'-hydroxy-T-2. HT-2 toxin, a deacetylated metabolite of T-2 toxin formed by reactions involving microsomal esterases, was also hydroxylated, to 3'-hydroxy HT-2 toxin. Experiments with inhibitors and inducers of the cytochrome P-450-dependent system revealed that these two hydroxylation reactions were catalysed by the cytochrome P-450-dependent monooxygenase system. Species comparisons using rats, mice, guinea-pigs, rabbits, pigs, cows and chickens showed that the rate of the hydroxylation reaction was highest in the hepatic microsomes of guinea-pigs, followed by mice. Chickens possessed a low activity both in the hydrolysis and hydroxylation reactions. No hydroxylated metabolites were produced by the intestinal microsomes of rabbits. These two hydroxylated metabolites were far less cytotoxic to Reuber hepatoma cells than the parent compound, T-2 toxin.

Dysplastic melanocytic nevus. Electron-microscopic observation as a diagnostic tool

Dysplastic melanocytic nevi (DMN) are distinctive cutaneous nevomelanocytic lesions that possess unique clinical and histopathological features. In our previous study, we showed that the fine structure of melanosomes in epidermal melanocytes of DMN are abnormal and reveal deranged melanogenesis. This study is an extension of our previous study and clarifies the fine structure of melanosomes in both epidermal melanocytes and keratinocytes with observations in an additional 10 cases of DMN with and without a marked mesenchymal response. We found that a poor mesenchymal response does not exclude fine structural abnormality of melanosomes in DMN; that abnormal melanosomes are manifested by a spherical shape with either fine granules or incompletely developed lamellae and/or both; that melanization occurs unevenly on the spherical granular and/or incompletely on the lamellar matrices; and that these abnormal melanosomes are transferred to keratinocytes before being completely melanized, and they reveal marked degradation. We suggest that the fine structural characterization of abnormal melanosomes is a new adjunct for histopathological diagnosis of DMN.

The distribution of GABA and glycine response in the mouse brain using Xenopus oocytes

Injection of mRNA from different regions of the central nervous system (CNS) of the mouse into the Xenopus oocyte caused a difference in the relative glycine to gamma-aminobutyric acid (GABA) response of the oocyte. Glycine caused the response in oocytes injected with brainstem mRNA but hardly in oocytes injected with cerebrum mRNA and in oocytes injected with cerebellum mRNA. In contrast, GABA caused the response in oocytes injected with mRNA from each of the 3 parts of the CNS. These obvious regional differences may reflect the distribution of the receptors to each plausible neurotransmitter in the CNS.

Aicardi syndrome with holoprosencephaly and cleft lip and palate

This 14-day-old Japanese girl demonstrated the classic features of Aicardi syndrome, including infantile spasms, agenesis of the corpus callosum, chorioretinopathy, microphthalmia, vertebral anomalies, electroencephalographic abnormalities, and severe mental retardation. Furthermore, she had a cleft lip and palate and a severe brain malformation due to semilobar-type holoprosencephaly. This patient is the second reported with Aicardi syndrome and associated cleft lip and posterior palate; she is the first patient with an additional severe brain malformation due to semilobar-type holoprosencephaly.

Once-daily administration of famotidine for reflux esophagitis

An open-labeled study of once-daily administration of 40 mg famotidine was conducted in 24 patients with endoscopically confirmed reflux esophagitis. The mean age of the patients was 62.8 years. Most had stage I or stage II esophagitis of 1 years' duration or less. After 4, 8, 12, and 16 weeks of treatment, endoscopically documented healing was reported in 50%, 75%, 82%, and 83% of patients, respectively. Among specific endoscopic findings documented at the start of the study there was clearing of white exudate in 83% of patients, and redness cleared in 50% of patients after 16 weeks of treatment. Symptomatic improvement was observed in 73% of patients after 2 weeks, and this increased to 81% and 85% after 4 and 8 weeks of treatment, respectively. Painful symptoms cleared within 2 weeks in 68% of patients, and this increased to 77% after 8 weeks of once-daily therapy. Famotidine was well tolerated. Historically, reflux esophagitis has not responded satisfactorily to drug treatment. The reported symptomatic response and the response documented by endoscopy after therapy with 40 mg famotidine once daily at bedtime are encouraging. Further studies should be conducted to define the role of famotidine in the treatment of reflux esophagitis.

Induction of taurine responsiveness in Xenopus oocytes by messenger RNA from mouse brain

A taurine response was induced in the surface membrane of the oocytes of Xenopus laevis by injection of the mRNA from the neonatal mouse brain, and the response was studied electrophysiologically. The permeability of mRNA-injected oocytes to chloride ions was increased by the application of taurine in a dose-dependent manner. The same oocyte also responded to GABA, but bicuculline suppressed only the GABA response. These results suggest a possibility that taurine could be a neurotransmitter of certain neurons as yet unknown in the central nervous system.