Polymorphism of the glutathione transferase subunit 3 in Sprague-Dawley rats involves a reactive cysteine residue

Comparison of Hirosaki hairless rat (HHR) and Sprague-Dawley (SD) rat liver glutathione transferase (GST) subunits by HPLC revealed differences in subunit 3; a new peak was detected in HHR GSTs and this was tentatively named X. By chromatofocusing, the HHR GST form composed of peak X and SD rat GST 3-3 were eluted at pH 8.8 and 9.1 respectively. The former was more sensitive to the SH reagent N-ethylmaleimide (NEM) than the latter. GSSG treatment of peak X resulted in a shift of retention time (peak Y) by HPLC analysis. However, such conversion was not observed for the SD rat GST 3-3 following GSSG or dithiothreitol (DTT) treatment. Peak Y exhibited m/z values of 26091.9 and 26125.4 by matrix-assisted laser-desorption ionization-time-of-flight MS, higher than those of peak X by 304-307, equivalent to the molecular-mass value of GSH. On treatment with DTT, peak Y was converted into peak X, with release of a substance with HPLC-characteristics of GSH. This substance was confirmed to be GSH by liquid chromatography/MS. These results thus indicated peak Y to be a glutathionylated form of peak X. Quantification revealed the release of 4 nmol of GSH from 0.12 mg of the peak Y protein, corresponding to 4.8 nmol (M(r) 25000). The nucleotide sequence of HHR GST subunit 3 cDNA proved identical to that reported for pGTA/C44, possessing asparagine and cysteine as the 198th and 199th amino acid residues, respectively, corresponding to lysine and serine in subunit 3 of the SD rat. Thus peak X appeared to be the product of HHR GST subunit 3 cDNA. Treatment with N-(4-dimethylamino-3,5-dinitrophenyl)maleimide, a coloured analogue of NEM, followed by trypsin-treatment and sequencing of labelled peptides, identified the reactive cysteine residue of HHR GST subunit 3 to be located at position 199. Unlike SD rat GST 3-3, HHR GST 3-3 was not activated by treatment with xanthine and xanthine oxidase. These results suggest polymorphism of the rat GST subunit 3 gene with individual gene product variation in sensitivity to oxidative stress.

High-frequency SEP components generated in the somatosensory cortex of the monkey

To investigate the origin of high-frequency somatosensory evoked potential (SEP) components, we recorded median nerve SEPs from the scalp and the depth in six monkeys. Laminar field potentials were analyzed in area 3b (N10; corresponding to human N20) and area 1 (P12; corresponding to human P25). After digital filtering (300-900 Hz), 4-6 components were identified, and the 1st to 4th peaks in area 3b (7-11 ms in latency) and the 3rd to 5th in area 1 (9-13 ms) showed clear polarity reversals between the surface and the depth of the cortex. These results provide direct evidence for intracortical origin of early high-frequency components in area 3b and of late ones in area 1.

Diminished function and expression of the cardiac Na+-Ca2+ exchanger in diabetic rats: implication in Ca2+ overload

1. The present work was carried out in order to determine whether a decrease in cardiac Na+-Ca2+ exchanger (NCX) activity observed in diabetes is caused by a reduction in NCX protein and mRNA levels and to elucidate the significance of this decrease in alterations in [Ca2+]i homeostasis in diabetic cardiomyocytes. 2. The NCX current was significantly reduced in ventricular myocytes freshly isolated from streptozotocin-induced diabetic rat hearts, and its current density was about 55 % of age-matched controls. 3. Diabetes resulted in a 30 % decrease in cardiac protein and mRNA levels of NCX1, a NCX isoform which is expressed at high levels in the heart. 4. The reduced NCX current and the decreased protein and mRNA levels of NCX1 in diabetes were prevented by insulin therapy. 5. Although both diastolic and peak systolic [Ca2+]i were not different between the two groups of myocytes, increasing external Ca2+ concentration to high levels greatly elevated diastolic [Ca2+]i in diabetic myocytes. Inhibition of NCX by reduction in extracellular Na+ by 50 % could produce a marked rise in diastolic [Ca2+]i in control myocytes in response to high Ca2+, as seen in diabetic myocytes. However, cyclopiazonic acid, an inhibitor of sarcoplasmic reticulum Ca2+ pump ATPase, did not modify the high Ca2+-induced changes in diastolic [Ca2+]i in either control or diabetic myocytes. 6. Only in papillary muscles from diabetic rats did the addition of high Ca2+ cause a marked rise in resting tension signifying a partial contracture that was possibly due to an increase in diastolic [Ca2+]i. 7. In conclusion, the diminished NCX function in diabetic myocytes shown in this study results in part from the decreased levels of cardiac NCX protein and mRNA. We suggest that this impaired NCX function may play an important role in alterations in Ca2+ handling when [Ca2+]i rises to pathological levels.

Activity-dependent conduction block in multifocal motor neuropathy

Patients with multifocal motor neuropathy may complain of muscle fatigue, even though the degree of conduction block assessed at rest has improved with treatment. To explore the mechanism involved, we examined changes in muscle force during maximum voluntary contraction (MVC) and monitored conduction block before and after MVC in five patients with multifocal motor neuropathy. The results were compared with those for the contralateral unaffected homonymous muscles. For one patient, who had bilateral involvement, a normal subject of a similar age and stature served as the control. Results of conduction studies were also compared with those from six patients with amyotrophic lateral sclerosis (ALS) with similar compound muscle action potential (CMAP) amplitudes after proximal stimulation. During MVC for 60 s, the affected muscles developed prominent fatigue; the force at the end of contraction compared with the initial force was significantly lower for the affected muscles [42 +/- 19% (mean +/- standard deviation) of the initial force] than for the control muscles (94 +/- 9%; P = 0.01). After MVC, the amplitude ratio of CMAPs after proximal versus distal nerve stimulation transiently decreased to 19 +/- 14% of that before MVC in the affected muscles, but not in the control muscles (94 +/- 3.8% of that before MVC) and in patients with ALS (95 +/- 6.7%). In one patient with a focal lesion in the forearm, nerve excitability was monitored at the lesion site before and after MVC for 120 s. There were significant increases in axonal threshold (approximately 48%) and supernormality (approximately 135%) immediately after MVC, suggesting that the axonal membrane had undergone hyperpolarization and, by extrapolation, that this had precipitated the conduction block. This study is the first to show that activity-dependent conduction block plays a role in human disease by causing muscle fatigue.

A lectin-histochemical study on the seminiferous epithelium of the northern smooth-tailed tree shrew (Dendrogale murina) and the Java tree shrew (Tupaia javanica)

Lectin-binding patterns in the testes of the northern smooth-tailed tree shrew, Dendrogale murina and Java tree shrew, Tupaia javanica were studied by light microscopy and compared the data with those of the common tree shrew. Four lectins (PNA, SBA, BPA and GS-II) were used in this study. Peanut (Arachis hypogaea) agglutinin (PNA), soybean (Glycine max) agglutinin (SBA) and Bauhinia purpurea agglutinin (BPA) showed a strong reaction in the acrosomal region from Golgi to acrosome-phase spermatids in three species of tree shrews. These lectins also showed a granular positive reaction in the cytoplasm from acrosome to maturation-phase spermatids in three species, except that BPA revealed no granular reaction (though it was positive) in the spermatid cytoplasm of the northern smooth-tailed tree shrew and that PNA revealed no reaction in the spermatid cytoplasm of the common tree shrew. While, Griffonia simplicifolia-II agglutinin (GS-II) showed a positive reaction in the acrosomal region of Golgi-phase spermatids in three species of tree shrews. Although GS-II was positive in the spermatocyte cytoplasm of three species, it showed granular in the northern smooth-tailed tree shrew and common tree shrew but not granular in the Java tree shrew. Thus, the lectin-binding patterns in testes were similar among three species belonging to the Order Scandentia. However, slight differences were also detected even among these phylogenetically-close species.

F-wave latency serves as the most reproducible measure in nerve conduction studies of diabetic polyneuropathy: multicentre analysis in healthy subjects and patients with diabetic polyneuropathy

AIMS/HYPOTHESIS

For use in future drug development for diabetic polyneuropathy, we conducted multicentre trials to assess the reproducibility of nerve conduction studies.

METHODS

All measurements were repeated twice at a time interval of 1-4 weeks in 132 healthy subjects (63 men) and 172 patients (99 men) with diabetic polyneuropathy. Using a standardised method, 32 centres participated in the study of control subjects and 65, in patients with diabetic polyneuropathy. Motor nerve conduction studies consisted of stimulating the left median and tibial nerves and recording the compound action potential from abductor policis and adductor hallucis for measuring amplitude, terminal latency and minimal F-wave latency. For sensory conduction studies, sensory nerve action potentials were recorded antidromically from the second digit and the posterior aspect of the lateral malleous after distal stimulation of the left median and sural nerves. We also calculated motor conduction velocity, F-wave conduction velocity and sensory conduction velocity. The relative intertrial variation and intraclass correlation coefficient were used as an index of reproducibility.

RESULTS

Of all the measurements, F-wave latency yielded the highest intraclass correlation coefficient with the smallest relative intertrial variation for both median and tibial nerves in both groups.

CONCLUSION/INTERPRETATION

Median and tibial F-wave latency provide the most reproducible measures for a nerve conduction study, serving as one of the best measures in multicentre drug trials for diabetic polyneuropathies.

Sympatric distribution of the two morphological types of the common tree shrew in Hat-Yai districts (South Thailand)

The two color types (grayish northern and reddish southern types) of the common tree shrew (Tupaia glis and Tupaia belangeri) were co-distributed in Hat-Yai region (South Thailand). Although the Isthmus of Kra in South Thailand has been considered as distribution barrier of the two types, the sympatric distribution of both types was confirmed in southern side of the Isthmus. In the principal component analysis, the skull measurement character from Hat-Yai region could also be separated into the northern and southern groups according to the skin color identification of corresponding individuals. We could generally distinguish the common tree shrew into two types by skull morphology as well as external skin color.

Membranous lipodystrophy presenting with palilalia: a PET study of cerebral glucose metabolism

A case of membranous lipodystrophy (Nasu-Hakola disease; NHD) associated with palilalia was reported. A 38-year-old Japanese woman developed walking difficulty in her twenties. At age 35 she manifested neuropsychiatric symptoms characterized by euphoria, palilalia and dementia. A bone marrow biopsy showed periodic acid Schiff-positive membranous cystic lesions in the adipose tissue. Positron emission tomography with (18F)-2-fluoro-2-deoxy-D-glucose disclosed that regional cerebral glucose metabolism was decreased in the bilateral frontal white matter with mild hypometabolism in the thalamus and basal ganglia; all predominantly on the right. Taken together with the previous postmortem findings, it is postulated that frontal lobe hypofunction, predominantly in the right hemisphere, produced the unique neuropsychiatric symptoms in this patient.

Cortical potentials associated with voluntary mandibular movements

Movement-related cortical potentials (MRCPs) are negative potentials over the scalp, which gradually increase prior to voluntary movements, and might be applied to elucidate the cortical efferent function of the mandibular movements. We compared the MRCPs accompanying various mandibular movements to study the motor control mechanism underlying these movements. Electroencephalograms (EEGs) were recorded from 11 electrodes placed over the scalp (F3, Fz, F4, T3, C3, Cz, C4, T4, P3, Pz, and P4), according to the International 10-20 System, and electromyograms (EMGs) were obtained from surface electrodes over the masseter muscle and the anterior belly of the digastric muscle. Ten healthy subjects were requested to make brisk and self-paced mandibular movements in 4 different directions (mouth-opening and -closing, and left and right lateral movements). We obtained MRCPs by averaging the EEG, using the visually determined EMG onset as a trigger signal. In all the movements, a slowly increasing, bilaterally widespread negativity starting 1.5 to 2.0 sec before the EMG onset (Bereitschaftspotential, or BP proper) was observed, with the maximum over the vertex region. The negative slope (NS') occurred about 300 to 700 msec before the EMG onset. The cortical maps of BP/NS' (BP and NS' combined), immediately prior to the mouth-opening and closing, showed a symmetrical distribution, whereas that for the lateral movements showed a tendency of predominance over the hemisphere ipsilateral to the direction of the movement. BP/NS' amplitudes at the onset of movement differed significantly or tended to do so between open, close, and lateral movements, suggesting that MRCP recordings may thus provide a means to explore the role of the cerebral cortex in the control of mandibular movements.

De novo trisomy 16p11.2-qter: report of an infant

We report on a four-month-old girl with a de novo trisomy 16q [47,XX, +del(16)(p11.2).ish del(16)(p11.2)(wcp16+,D16Z2+,tel16q+, tel16p-)]. She had minor facial anomalies, limb anomalies, urogenital abnormalities, and severe cardiovascular defects. Autopsy confirmed left hypoplastic lung, total anomalous pulmonary venous drainage via coronary sinus, persistent left superior vena cava, patent ductus arteriosus, secundum atrial septal defect, bilateral hydronephrosis and hydroureters, uterus bicornis, and ovarian hypoplasia. Short tandem repeat polymorphism analysis indicated that the additional, structurally abnormal chromosome 16 was maternal in origin.

Synergistic effects of FGF and non-ridge ectoderm on gene expression involved in the formation of the anteroposterior axis of the chick limb bud in cell culture

Skeletal patterning of the vertebrate limb is controlled by the zone of polarizing activity (ZPA), apical ectodermal ridge (AER) and dorsal ectoderm. In the present study, to understand the involvement of fibroblast growth factor (FGF) and non-ridge ectoderm in anteroposterior (AP) axis formation, gene expression in chick limb bud mesenchymal cells in culture was investigated by reverse transcription-polymerase chain reaction and in situ hybridization. It was found that Shh expression was locally maintained in the mesenchymal cells underneath and near non-ridge ectoderm in coculture with the posterior mesenchymal cells and non-ridge ectoderm in the presence of FGF-4 by in situ hybridization. In Shh-expressing anterior limb bud mesenchymal cells cultured with non-ridge ectoderm, it was also discovered that Bmp-2 was activated in the presence of FGF-2, -4 and -8, while Hoxd-13 was activated in the presence of FGF-4 and that FGF-2 had a similar effect but FGF-8 did not. This result indicates that Hoxd-13 activation by SHH depends on non-ridge ectoderm and FGF-2 or FGF-4, and that there may be a difference in the effect on AP axis formation of the limb bud between FGF-2, -4 and -8. Possible roles of these genes and signal molecules in AP pattern formation are discussed.

Chronic motor axonal neuropathy associated with antibodies monospecific for N-acetylgalactosaminyl GD1a

We report on three patients with chronic motor neuropathy who had elevated titers of immunoglobulin (Ig)G antibodies against N-acetylgalactosaminyl GD1a (GalNAc-GD1a) and normal titers of antibodies against other gangliosides. Presenting with progressive muscular atrophy, fasciculations, and no sensory deficits, the patients had been diagnosed to have motor neuron disease. Electrodiagnostic features were predominantly axonal. Two patients clinically improved after intravenous Ig infusion and cyclophosphamide therapy. Increased titers of IgM antibodies to GalNAc-GD1a were also found in two of 15 patients with multifocal motor neuropathy with conduction block but were associated with concomitant rise of anti-GM1 antibodies. These three cases represent a chronic motor axonal neuropathy in which antibody testing for a minor ganglioside was helpful for instituting therapy.

Osteometrical skull character in the four species of tree shrew

The skull size and shape were osteometrically examined in the four species of the tree shrews (Tupaia tana, T. javanica, T. minor and T. dorsalis). We suggest that the skull characters were affected by the species specific behavior and terrestrial, arbo-terrestrial and arboreal life, among the genus Tupaia. The neurocranium was laterally narrower in the braincase area, and the splanchnocranium was longer only on dorsal side in T. tana, and these characters were opposite to T. minor. The principal component analysis confirmed the obviously separated clusters among T. tana, T. javanica and T. minor, affected by the adaptation for each behavior. T. dorsalis was considered as terrestrial species from the results of proportion analysis and the principal component analysis.

Effect of maturation on nerve excitability in an experimental model of threshold electrotonus

Threshold electrotonus (TE) is a new tool for investigating axonal function noninvasively in vivo. To increase its potential clinical value, we developed a rat model of TE, and examined the effects of maturation and pharmacological intervention. We recorded TE in 92 male rats (body weight 90-650 g) by stimulating the motor nerve in the tail, and applying 100-ms conditioning currents. Motor conduction velocities increased up to a body weight of 330 g, and remained constant thereafter. TE in mature rats was similar to that in humans, and two parameters were analyzed: TEd(10-20) or the mean threshold reduction 10-20 ms after the onset of the depolarizing conditioning current at 40% of threshold intensity; and TEh(10-20) or the corresponding threshold decrease on hyperpolarization. Like latency, the absolute value of TEh(10-20) decreased up to 330 g, and then stabilized thereafter, probably reflecting the progressive increase in the axonal diameter and relative reduction in internodal impedance. In contrast, TEd(10-20) gradually decreased up to 330 g, and then jumped to a higher level, which was maintained for animals of >400 g. 4-Aminopyridine, a blocker of fast potassium channels, selectively increased TEd(10-20) only in the immature or young (<330 g) rats. This suggests that, in the mature animals, fast potassium channels become sequestrated from the nodal membrane and not activated in response to nodal depolarization. These findings indicate that mature rats (>400 g) may provide a useful experimental model for interpreting abnormal TE responses in humans, and provide evidence for nonlinear maturation of potassium channel function in myelinated axons.

Multivariate analysis in skull osteometry of the common tree shrew from both sides of the Isthmus of Kra in Southern Thailand

The Isthmus of Kra in Southern Thailand consists of a lowland of about 70 km in length. It has been suggested that the Isthmus may sink beneath the sea surface according to the change of level of the sea, and may function as a zoogeographical barrier in land mammals in this region. So, the geographical variation was osteometrically examined in skull of the common tree shrew (Tupaia glis) from the both sides of Isthmus of Kra. The osteometrical examination demonstrated that the skull is larger in southern population than in northern one. In the charts of the principal component analysis, however, the morphological separation between two populations can not be obviously seen in female. While, the results of the discriminant analysis indicated the morphological separation between the two populations. These findings suggest that the zoogeographical barrier of Isthmus of Kra may have influence on the osteometrical variation in the common tree shrew, when the Isthmus was covered with sea.

Two new spongian diterpenes from Coscinoderma mathewsi

Two new spongian diterpenes were isolated from the sponge, Coscinoderma mathewsi. One possesses a tricyclic skeleton bearing an aldehyde function, the other is a tetracyclic lactol. The structures of two compounds are elucidated by spectral method.

Lectin histochemistry of the canine anal glands

The distribution and selectivity of complex carbohydrates in the canine anal glands were studied by means of lectin histochemistry, using PO-labeled lectins. The secretory epithelium of the anal glands and the excretory duct system exhibited large amounts of mainly neutral glycoproteins with various terminal sugars (alpha-D-mannose, beta-N-acetyl-D-glucosamine, alpha-N-acetyl-D-galactosamine, alpha-D-galactose, alpha-L-fucose, N-acetyl-neuraminic acid). Distinctly prominent in the secretion were alpha-L-fucose residues. This relatively hydrophobic sugar may in particular modify or control the viscoelastic properties of the anal gland mucus, so that a stable mucous coat of the rather dry faeces can be formed. In addition, it was obvious that the major part of the excretory duct system is also involved in secretion production, and that the essential function of the saccular dilatations of the excretory ducts is to ensure secretion maturation.

Effects of AMP derivatives on cyclic AMP levels in NG108-15 cells

1. In NG108-15 neuroblastomaxglioma hybrid cells, ATP stimulates intracellular cyclic AMP formation, which is inhibited by both adenosine (P(1)) and P2 receptor antagonists. In the present study, we examined the effects of several AMP derivatives in NG108-15 cells and mouse neuroblastoma N18TG-2 cells. 2. Adenosine 2'-monophosphate (A2P), adenosine 3'-monophosphate (A3P) and adenosine 5'-phosphosulphate (A5PS) increased cyclic AMP levels with similar concentration-dependencies in NG108-15 cells. 3. Increases in cyclic AMP by AMP derivatives were inhibited by the P2 receptor antagonist PPADS, but not by suramin. Effects of AMP derivatives were also inhibited by P(1) receptor antagonists ZM241385, XAC, DPCPX and partially by alloxazine. The ecto-nucleotidase inhibitor alpha, beta-methyleneADP was without effect. 4. In contrast, AMP derivatives did not change cyclic AMP levels in N18TG-2 cells. Accumulation of cyclic AMP in N18TG-2 cells was stimulated by adenosine A(2) receptor agonists CGS21680 and NECA, but not by ATP or beta, gamma-methyleneATP, agonists for cyclic AMP production in NG108-15 cells. 5. Reverse transcription-coupled polymerase chain reaction (RT - PCR) analyses revealed that N18TG-2 cells express both A(2A) and A(2B) receptors, while NG108-15 cells express mainly A(2A) receptors. 6. AMP derivatives did not affect the P2X and P2Y receptors expressed in NG108-15 cells. 7. These results suggest that A2P, A3P and A5PS act as agonists for cyclic AMP production and that these compounds are valuable tools for determinating the mechanism of ATP-stimulated cyclic AMP response in NG108-15 cells.

Human presupplementary motor area is active before voluntary movement: subdural recording of Bereitschaftspotential from medial frontal cortex

Bereitschaftspotential (BP) was recorded directly from the right supplementary motor area proper (SMA-proper) and its rostral part by chronically implanted subdural electrodes in three patients with intractable focal motor seizure. Cortical electrical stimulation of the SMA-proper revealed the somatotopy as previously reported, and the supplementary negative motor area (SNMA) was identified just anterior to the SMA-proper in two of three cases. In patient 1, eight kinds of simple movements, i.e., left and right middle finger extension, left arm abduction, left and right foot dorsiflexion, left knee extension, tongue protrusion and saccadic eye movement, were studied to record BP. In patient 2, three kinds of movements, i.e., left and right middle finger extension and left foot dorsiflexion, were adopted as movement tasks. In patient 3, four kinds of movements, i.e., left and right middle finger extension and left and right foot dorsiflexion, were adopted. In the SMA-proper, somatotopically distributed BP preceding movements were observed in all three patients. In the SNMA and its rostrally adjacent areas, "SNMA-plus" BPs were generated invariably regardless of the sites of movement. There was no significant difference in the onset time of BPs between the SMA-proper and the SNMA-plus. The present findings suggest that the SNMA-plus is more consistently involved in the preparation for various simple movements than the SMA-proper. This functionally independent region (SNMA-plus) just rostral to the SMA-proper most likely corresponds to a part of the presupplementary motor area which was originally defined in nonhuman primates. Since a part of this area elicited the inhibition of various movements by cortical stimulation, and since it generated BPs regardless of the sites of movement, it may play a higher role in the movement preparatory process than the SMA-proper.

Inhibitory action of troglitazone, an insulin-sensitizing agent, on the calcium current in cardiac ventricular cells of guinea pig

We investigated the effects of troglitazone, a new orally active hypoglycemic agent, on the voltage-dependent L-type Ca2+ current in single cardiac ventricular myocytes of guinea pigs by the whole-cell voltage clamp technique. Troglitazone blocked the Ca2+ currents in a concentration-dependent manner. The inhibitory effect was more potent at the holding potential (HP) of - 50 mV than at - 80 mV. The half-maximum inhibiting concentration (IC50) of troglitazone was 0.8 microM with the Hill coefficient of 0.84 at -50 mV HP. In contrast, the IC50 value was higher than 10 microM at -80 mV HP. These results suggest that troglitazone at therapeutic concentrations inhibit the Ca2+ channels and may exert cardioprotective effects in diabetic conditions.

Effects of P(1) and P2 receptor antagonists on beta, gamma-methyleneATP- and CGS21680-induced cyclic AMP formation in NG108-15 cells

1. We have previously shown that ATP increased cyclic AMP in NG108-15 cells, which was inhibited by P(1) receptor antagonist methylxanthines. In the present study, we examined the effects of P(1) and P2 receptor antagonists on cyclic AMP formation induced by beta,gamma-methyleneATP (beta,gamma-MeATP) and CGS21680, an A(2A) adenosine receptor agonist, in NG108-15 cells. 2. beta,gamma-MeATP and CGS21680 increased intracellular cyclic AMP with EC(50) values of 8. 0+/-0.98 microM (n=4) and 42+/-7.5 nM (n=4), respectively. 3. Several P(1) receptor antagonists inhibited both beta,gamma-MeATP- and CGS21680-induced cyclic AMP increase with a similar rank order of potency; ZM241385>CGS15943>XAC>DPCPX. However, the pK(i) values of these antagonists for beta,gamma-MeATP were larger than those for CGS21680. 4. Alloxazine, a P(1) receptor antagonist, and several P2 receptor antagonists (PPADS, iPPADS, reactive blue-2) inhibited beta, gamma-MeATP-induced response, while these antagonists little affected CGS21680-induced one. Suramin was effective only for beta, gamma-MeATP-induced response at 1 mM. 5. 2-chloroadenosine (2CADO) and 2-chloroATP (2ClATP) increased cyclic AMP with similar potencies. The effects of these agonists were both inhibited by ZM241385, but only 2ClATP-induced response was inhibited by PPADS. 6. ATP- and beta, gamma-MeATP-induced responses were little affected by alpha, beta-methyleneADP, a 5'-nucleotidase inhibitor. 7. These results clearly demonstrate that ATP-stimulated cyclic AMP formation can be distinguished from the A(2A) receptor agonist-induced one by using the several P(1) and P2 receptor antagonists.

Inverse relationship between circulating oxidized low density lipoprotein (oxLDL) and anti-oxLDL antibody levels in healthy subjects

Oxidized low density lipoprotein (oxLDL) has been implicated in the pathogenesis of atherosclerosis. Recent studies have shown that immunization of animals with oxLDL results in suppression of atherogenesis. Antibody against oxLDL (oxLDL Ab) is detectable in human sera, although its biological significance is not well established. We examined the relationship between oxLDL Ab titer and circulating oxLDL level in 130 healthy Japanese subjects. OxLDL was measured as apolipoprotein (apo) B-containing lipoproteins carrying oxidized phosphatidylcholines by a sensitive ELISA. IgG class oxLDL Ab titer was measured by ELISA. Plasma oxLDL concentration was very low and it corresponded on average to one to two out of 1000 apoB-containing lipoproteins in plasma. Plasma oxLDL correlated positively with LDL cholesterol and inversely with oxLDL Ab titer. These associations remained significant and independent in multiple regression analysis including age, gender, smoking, and high-density lipoprotein cholesterol. These data indicate that healthy subjects have a very low concentration of oxLDL in the circulation, and that oxLDL Ab titer is in an inverse relationship with plasma oxLDL concentration in this population. Although these results suggest that oxLDL Ab may play a role in maintaining the low level of plasma oxLDL, its role in atherogenesis awaits further studies.

Frontonasal dysplasia, macroblepharon, eyelid colobomas, ear anomalies, macrostomia, mental retardation, and CNS structural anomalies: another observation

We report a Japanese girl with brachycephaly, a wide forehead, hypertelorism, macroblepharon with eyelid colobomas, ectropion, a broad nasal root, a depressed nasal tip, macrostomia, a small and grooved chin, ear anomalies, a structural anomaly of the corpus callosum, dilatation of the fourth ventricle, a urogenital sinus, and mental retardation. Cause and inheritance are unknown.

Apple-peel intestinal atresia associated with balanced reciprocal translocation t(2;3)(q31.3;p24.2) mat

Apple peel intestinal atresia is an apple-peel-appearing bowel obstruction of unknown cause. We describe a Japanese girl with the apple-peel jejunal atresia associated with apparently balanced reciprocal translocation between chromosomes 2 and 3, t(2;3)(q31. 3;p24.2)mat. The translocation breakpoints in the patient may become candidate regions for the putative gene causing apple-peel atresia. Alternatively, the association of the two abnormalities in the patient is coincidental because her phenotypically normal mother had the same chromosome translocation.

Morphology of the intestinal tract in the white rhinoceros (Ceratotherium simum)

The intestinal tract of the white rhinoceros (Ceratotherium simun) was dissected. We observed a simple structure for the small intestine, duodenum, jejunum and ileum, and a well-developed large intestine, cecum, colon and rectus. The cecum consisted of a small chamber, whereas the colon was much enlarged; notably larger than that of the domesticated horse, which belongs to the same order, Perissodactyla. This suggests that in the white rhinoceros the cecum may be functionally replaced by the well-developed colon which may act as the main fermentation tank in this animal.

Long-term effects of dietary alpha-linolenic acid from perilla oil on serum fatty acids composition and on the risk factors of coronary heart disease in Japanese elderly subjects

Although important roles of dietary n-3 fatty acids in the prevention of coronary heart disease (CHD) have been suggested, long-term effects of dietary alpha-linolenic acid (ALA, 18:3n-3) have not yet been established under controlled conditions. We tested whether a moderate increase of dietary ALA affects fatty acids composition in serum and the risk factors of CHD. Oxidized LDL (OxLDL) was directly measured by ELISA using antibody specific to OxLDL. By merely replacing soybean cooking oil (SO) with perilla oil (PO) (i.e., increasing 3 g/d of ALA), the n-6/n-3 ratio in the diet was changed from 4:1 to 1:1. Twenty Japanese elderly subjects were initially given a SO diet for at least 6 mo (baseline period), a PO diet for 10 mo (intervention period), and then returned to the previous SO diet (washout period). ALA in the total serum lipid increased from 0.8 to 1.6% after 3 mo on the PO diet, but EPA and DHA increased in a later time, at 10 mo after the PO diet, from 2.5 to 3.6% and 5.3 to 6.4%, respectively (p<0.05), and then returned to baseline in the washout period. In spite of increases of serum n-3 fatty acids, the OxLDL concentration did not change significantly when given the PO diet. Body weight, total serum cholesterol, triacylglycerol, glucose, insulin and HbA1c concentrations, platelet count and aggregation function, prothrombin time, partial thromboplastin time, fibrinogen and PAI-1 concentration, and other routine blood analysis did not change significantly when given the PO diet. These data indicate that, even in elderly subjects, a 3 g/d increase of dietary ALA could increase serum EPA and DHA in 10 mo without any major adverse effects.

Association of microphthalmia with esophageal atresia: report of two new patients and review of the literature

We report on two new patients who had unilateral microphthalmia and esophageal atresia. A similar association was previously described in six patients. The accumulation of the eight affected patients provides further support for recognizing this association as a distinct syndrome.

Differential expression of small heat shock proteins in reactive astrocytes after focal ischemia: possible role of beta-adrenergic receptor

Small heat shock proteins (sHSPs), a family of HSPs, are known to accumulate in the CNS, mainly in astrocytes, in several pathological conditions such as Alexander's disease, Alzheimer's disease, and Creutzfeldt-Jakob disease. sHSPs may act not only as molecular chaperones, protecting against various stress stimuli, but may also play a physiological role in regulating cell differentiation and proliferation. In the present study, we have demonstrated that transient focal ischemia in rats dramatically induced HSP27 but not alpha B-crystallin (alphaBC), both of which are members of sHSPs, in reactive astrocytes. In contrast, in vitro chemical ischemic stress induced both HSP27 and alphaBC in cultured glial cells to the same extent. Dibutyryl cAMP (dBcAMP) and isoproterenol, a beta-adrenergic receptor (betaAR) agonist, enhanced HSP27 expression but suppressed alphaBC, and changed the shape of the cells to a stellate form. dBcAMP and isoproterenol inhibited cell proliferation under normal conditions. An increase in betaAR-like immunoreactivity was also observed in reactive astrocytes in vivo. These results, together with recent findings that betaAR plays an important role in glial scar formation in vivo, raise the possibility that betaAR activation modulates sHSP expression after focal ischemia and is involved in the transformation of astrocytes to their reactive form.

Brain arteriolosclerosis and hemodynamic disturbance may induce leukoaraiosis

OBJECTIVE

To investigate whether internal carotid artery (ICA) occlusive disease-induced hemodynamic disturbance is associated with extensive white matter high-intensity lesions (WMLs) on T2-weighted MR images in the hemisphere with lacunar infarct in the basal ganglia.

BACKGROUND

Hemodynamic disturbance in the brain with arteriolosclerosis may be one of the mechanisms by which ischemic injury induces extensive WMLs.

METHODS

The authors used MRI and PET to study 21 patients with unilateral ICA occlusion or stenosis and lacunar infarct in the bilateral basal ganglia. In hemispheres with ICA disease, the association of WMLs with the mean hemispheric values of oxygen extraction fraction (OEF)-an index of hemodynamic compromise-measured with the 15O-labeled gas steady-state technique was analyzed. Twenty-five patients with ICA occlusive disease without lacunar infarct were studied as control subjects.

RESULTS

In the hemispheres with ICA disease, patients with lacunar infarct had a significantly greater severity of WMLs than control subjects, although the mean hemispheric values of the OEF showed no significant difference. The severity of WMLs correlated significantly with the mean hemispheric values of the OEF in patients with lacunar infarct, but not in control subjects. Multivariate analysis revealed that lacunar infarcts and increased OEF were independent predictors of extensive WMLs, with lacunar infarcts the most heavily weighted factor.

CONCLUSION

Internal carotid artery occlusive disease-induced hemodynamic disturbance is associated with extensive WMLs in hemispheres with lacunar infarct. Hemodynamic disturbance may contribute to the development of extensive WMLs, although brain arteriolosclerosis may be a major contributing factor.

Aberrant expression of cyclin-dependent kinase 5 in inclusion body myositis

OBJECTIVE

To investigate abnormal protein expression in inclusion body myositis (IBM).

BACKGROUND

In IBM, ectopic deposition of beta-amyloid protein as well as several other proteins in some muscle fibers occurs. Some, but not all, of these proteins are also expressed in myofibrillar myopathy (MFM). The authors recently reported aberrant expressions of several cyclin-dependent kinases (CDKs)-enzymes regulating the cell replication cycle-in MFM. They therefore tested the notion that aberrant expression of CDKs also occurs in IBM. Among CDKs, CDK1, CDK2, and CDK5 have been demonstrated to phosphorylate tau, which is a component of inclusions in IBM. CDK5 appears in a stage of myogenesis when CDK1 and CDK2 are downregulated.

METHODS

Cryostat sections of muscle specimens from 10 patients with sporadic IBM were immunostained for CDK1, CDK2, and CDK5. Fourteen patients with polymyositis and eight individuals with dermatomyositis served as disease control subjects.

RESULTS

In IBM, numerous CDK5-positive inclusions were present in vacuolated fibers. CDK5 expression was not observed in any disease control subject. Regenerating fibers expressed CDK1 and CDK2 in all diseases.

CONCLUSION

The results suggest that cyclin-dependent kinases (CDK)5, but no other CDKs, is involved in the formation of inclusions in IBM.

Direction-independent block of bi-directional Na+/Ca2+ exchange current by KB-R7943 in guinea-pig cardiac myocytes

1. We investigated the inhibitory effect of KB-R7943 on 'bi-directional' Na+/Ca2+ exchange current (iNCX) with the reversal potential of iNCX (ENCX) in the middle of the ramp voltage pulse employed. 2. Bi-directional iNCX was recorded with 'full' ramp pulses given every 10 s from the holding potential of -60 mV over the voltage range between 30 and -150 mV under the ionic conditions of 140 mM [Na]o, 20 mM [Na]i, 1 mM [Ca]o and 433 nM [Ca]i with calculated ENCX at -50 mV. 3. KB-R7943 (0.1 - 100 mirconM) concentration-dependently inhibited the current, which reversed near the calculated ENCX, indicating that the blocked current was iNCX. 4. The inhibition levels were not significantly different between outward and inward iNCX measured at 0 and -120 mV, respectively. IC50 of KB-R7943 was approximately 1 micronM for both directions of iNCX. 5. Under the bi-directional ionic conditions, only an outward or inward iNCX was induced by positive or negative 'half' ramp pulses, respectively, from the holding potential of -60 mV. KB-R7943 inhibited both direction of iNCX and the concentration-inhibition relations were superimposable to the ones obtained by 'full' ramp pulses. 6. These results indicate that KB-R7943 inhibits iNCX direction-independently under bi-directional conditions. This conclusion is different from that of our previous results obtained from iNCX under uni-directional ionic conditions, where KB-R7943 inhibited iNCX direction-dependently. The difference could be attributed to slow dissociation of the drug from the exchanger.

Anophthalmia in litters of female rats treated with the food-derived carcinogen, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine

Anophthalmia in litters of pregnant rats treated with 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a food-derived carcinogen, was incidentally encountered in a risk-assessment study with 2-generation exposure to PhIP. Female Fischer 344 animals were given 200 ppm PhIP in the diet for 4 wk before mating with nontreated males and also during gestation and lactation periods. Mean numbers of newborn rats per litter in control and PhIP-treated groups were 7.9 +/- 2.9 and 7.1 +/- 1.6 in trial 1 and 8.3 +/- 1.9 and 6.1 +/- 2.4 in trial 2. Among 49 (trial 1) and 63 (trial 2) offspring from PhIP-treated dams, 9 (18.4%) and 32 (50.8%) demonstrated anophthalmia, and 1 (2.0%) and 8 (12.7%) demonstrated hydrocephaly. Five of 7 (71.4%) and 13 of 14 (92.9%) dams delivered pups with malformations in trials 1 and 2, respectively. Also, in a previous study that was carried out with the same protocol and that used the Sprague-Dawley strain of rats, anophthalmia and hydrocephaly were observed in 2 and 1 out of 175 pups, respectively, from 100 ppm PhIP-treated dams. No congenital malformations were found in control groups of the same size in either experiment. In addition to having been previously identified as a cause of carcinogenic activity, our findings suggest that PhIP is capable of causing anophthalmia in rats when administered during the gestational period.

Selective induction of glial glutamate transporter GLT-1 by hypertonic stress in C6 glioma cells

Glial glutamate transporter GLT-1 mRNA was selectively induced in C6 glioma cells exposed to hypertonic stress (HS), while the expression of two other subtypes, GLAST and EAAC1, was suppressed. HS increased phosphorylation of the MAPK family, ERK, p38 MAPK, and JNK. Treatment with a PKC inhibitor showed that phosphorylation of both p38 MAPK and JNK is PKC-dependent but ERK phosphorylation is independent. Inhibition of either ERK or p38 MAPK did not abolish GLT-1 mRNA induction. Inhibition of PKC also had no effect. These findings indicate that the induction of GLT-1 mRNA by HS is independent of the MAPK pathways. This is the first report that the expression of glial glutamate transporters is osmotically regulated.

Combined use of type A and F botulinum toxins for blepharospasm: a double-blind controlled trial

Type A botulinum toxin has widened its clinical range of applications, but the risk of developing antibodies limits the repeated use of high-dose injection. To minimize the risk, mixing different types of toxin might reduce the antigenic presentation of a specific toxin and associated proteins. At the same time, inhibition of the neuromuscular release process at the multiple sites might potentiate the clinical response or the duration of action. We compared the effectiveness of a mixture of type A and type F botulinum toxins with that of type A or type F toxin alone for treating patients with blepharospasm in a double-blind study. Fifty-four patients had 10 units of toxin injection, a mixture of type A and F toxins (including 5 units of each) on one side and either type A or F toxin on the other side of the orbicularis oculi muscle. Clinical evaluation at 4 and 10 weeks after the injection revealed that the peak clinical effect at 4 weeks was similar among the three preparations. The duration of action of the mixture was intermediate between type A and type F alone, as assessed at 10 weeks, when there was a tendency of conserving the beneficial effect on one eye at the expense of that on the other. Although there was no apparent potentiation of the clinical efficacy, the combination of these different types of toxin might be used for decreasing the risk of antibody development.

[Cooperative study of intraarterial preventive chemotherapy after resection of hepatic metastasis from colorectal cancer]

This is a compilation of the results of preventive intraarterial infusion following resection of hepatic metastasis from colorectal cancer at four surgical centers. The cases studied included two groups: A) 76 patients who underwent normal liver resection only, and B) 78 patients who underwent resection with adjuvant chemotherapy. Methods included: 1) WHF, 50 cases; 2) other methods using 5-FU, 18 cases; and 3) intraarterial infusions other than 5-FU, 10 (2 cases, outcome unknown). Survival rates for groups A and B for 1 and 5 years were 71.2, 18.9% and 91.5, 56.2%, respectively, with the rates for the intraarterial infusion group showing far better results. The 1- and 5-year survival rates in terms of infusion methods were: 1) 90.7% and 64.6%; 2) 94.4% and 39.3%; and 3) 90% and 60%, respectively, showing no remarkable differences between methods. Total doses of 5-FU were (a) less than 5 g, 7 patients (b) 5-15 g, 16 patients (c) 15-30 g, 22 patients (d) greater than 30 g, 23 patients. A comparison of 1- and 5-year survival rates shows (a) 85.7% and 17.1%; (b) 66.5% and 44.3%; (c) 100% and 62.7%; (d) 100% and 66.5%, respectively, with doses (c) and (d) showing markedly better results than the (a) dosage. From this we conclude that the group undergoing intraarterial hepatic infusion had a markedly improved prognosis compared to the group not undergoing any type of adjuvant therapy. Also, groups receiving a dosage of 15 g or greater of 5-FU showed prolonged survival rates.

Pathogenesis of idiopathic scoliosis. Experimental study in rats

STUDY DESIGN

A radiographic examination of pinealectomized rats to observe the development of scoliosis and halt the condition by administration of melatonin.

OBJECTIVES

To discover whether pinealectomy has the same effect in mammals as shown in the chicken, and to determine whether the bipedal condition is important for development of scoliosis.

SUMMARY OF BACKGROUND DATA

Pinealectomizing chickens shortly after hatching consistently resulted in scoliosis closely resembling human idiopathic scoliosis. It has not been determined whether this phenomenon is restricted solely to chickens, or if this experimental model is applicable to other animals, especially those more closely related to humans.

METHODS

A sham operation in five bipedal rats served as the control in this study. Pinealectomy was performed in 10 quadrupedal rats, pinealectomy in 20 bipedal rats, and pinealectomy with implantation of melatonin pellet in 10 bipedal rats. Spinal radiographs were used to measure the degree of scoliosis at 3 months after surgery.

RESULTS

Scoliosis developed only in pinealectomized bipedal rats and not in quadrupedal rats. It developed in none of the sham operation group and in only 1 of 10 pinealectomized bipedal rats with melatonin treatment.

CONCLUSIONS

Melatonin deficiency secondary to pinealectomy alone does not produce scoliosis if the quadrupedal condition is maintained. The bipedal condition, such as that in chickens or humans, plays an important role in the development of scoliosis. The findings suggest a critical influence of a postural mechanism for the development of scoliosis.

Frequent mutation of beta-catenin and APC genes in primary colorectal tumors from patients with hereditary nonpolyposis colorectal cancer

Hereditary nonpolyposis colorectal cancer (HNPCC) is characterized by defective DNA mismatch repair, which results in genetic instability of tumors; however, only a few target genes have been recognized. Our previous study detected a low frequency of APC gene mutation (21%) in colorectal tumors from HNPCC patients, in contrast to a high frequency of APC gene alteration (>70%) in non-HNPCC tumors. Because both beta-catenin and ACP gene mutations have recently been shown to activate the same signaling pathway, we analyzed beta-catenin mutation in HNPCC tumors. A notable frequency of beta-catenin gene mutation (43%, 12 of 28) was found to occur in HNPCC colorectal tumors. Beta-catenin mutations were not detected in tumors with APC mutations. All beta-catenin mutations detected in HNPCC tumors existed within the regulatory domain of beta-catenin. Immunohistochemical staining of tumors with this mutation showed accumulation of beta-catenin protein in nuclei. These and previous data from our laboratory suggest that activation of the beta-catenin-Tcf signaling pathway, through either beta-catenin or APC mutation, contributes to HNPCC colorectal carcinogenesis in approximately 65% of cases.