[Protective effect of nitric oxide on ischemic retina]

Nitric oxide (NO) is a free radical and was regarded as noxious to life. But recent studies show that NO is an important substance for transcellular signal transduction. It also seems to act as a neurotransmitter in the nervous system. In ischemic nerve tissue a release of glutamate is one of the critical factors that increase neuronal death, and some experiments suggest that NO may be involved in this process. Here we provide evidence that NO provides neuroprotection in ischemic retinas in vivo. Albino rabbits' eyes were subjected to 60 minutes of ischemia by raising intraocular pressure. Before ischemia the eyes were treated intravitreously with the NO-precursor L-arginine, the NO synthase-inhibitor nitro-L-arginine methyl ester hydrochloride (L-NAME), the NO-donor sodium nitroprusside (SNP), or solvent only. The amplitude of the b-wave was measured and the recovery ratio of the b-wave was analyzed hourly after reperfusion. The recovery ratio of b-wave in the eyes with L-arginine and with SNP increased more rapidly than in the controls, while the recovery ratio in the eyes with L-NAME increased in a way similar to that of the controls. These results suggest that NO plays a neuroprotective role in ischemic retina. It may be involved with S-nitrosylation of some proteins, including one of the glutamate receptors, the N-methyl-D-aspertate (NMDA) receptor.

Separation of 18 6-aminoquinolyl-carbamyl-amino acids by ion-pair chromatography

Eighteen 6-aminoquinolyl-carbamyl (AQC)-amino acids were separated by ion-pair chromatography, using tetrabutylammonium (TBA) as a counterion. Optimum separation was obtained on a C8 reverse-phase column using gradient elution with two mobile phases, A (5 mM TBA, 75 mM ammonium acetate, pH 7.5) and B (80% acetonitrile). The AQC-amino acids were detected by fluorescence with excitation at 250 nm and emission at 395 nm, and the analysis time was 65 min. The response factors of individual AQC-amino acids to AQC-phenylalanine ranged from 0.42 to 1.08 (except for tryptophan at 0.01), with an average of 0.8. Detection limits by fluorescence ranged from 11.8 fmol (threonine) to 51.7 fmol (methionine), except for tryptophan (1.8 pmol).

How are macular changes reflected in pattern visually evoked cortical potentials?

To investigate the macular contribution to the amplitude and latency of pattern visual evoked cortical potentials (PVECPs), we recorded PVECPs in patients with unilateral macular disease (retinal diseases involving the macular region) and optic neuritis. We selected patients with visual acuities better than 0.3, which is thought to be the minimum acuity to provide clearly discernible responses. The visual stimulus was a checkerboard. We varied the check size in 4 steps as 7, 14, 28, and 56 min of arc, and the contrast was 20% or 80%. The amplitude of the sinusoidal wave of steady-state VECPs (12 Hz) and the P100 component of a transient VECP (3 Hz) were measured. Significant attenuation and delay of PVECPs in the affected eye were found in the macular disease group. Macular disease may cause an increase of VECP latency. However, VECP seemed to be a more sensitive test of optic nerve disease than of macular disease, when patients had similar visual acuities.

Isolated 3-methylcrotonyl-CoA carboxylase deficiency in a 15-year-old girl

A 15-year-old girl with a former clinical diagnosis of cerebral palsy was found to have isolated deficiency of 3-methylcrotonyl-CoA carboxylase (MCC) on gas chromatography-mass spectrometry (GC/MS) analysis and enzyme determination. Her symptoms included marked growth retardation from birth, profound mental retardation, tonic seizures, rigospastic quadriplegia with opisthotonic dystonia, gastroesophageal reflux with poor esophageal peristalsis, and recurrent episodes of aspiration pneumonia. Brain MRI revealed marked brain atrophy, involving both the gray and white matter. Although she did not exhibit acute metabolic decompensation or acute encephalopathy, her neurological symptoms continuously worsened. This patient is the oldest among reported cases of MCC deficiency who had symptoms at birth, and this case may have the severest sequelae of the longest known natural course of this inborn error of metabolism.

The structure of Silurus asotus (catfish) roe lectin (SAL): identification of a noncovalent trimer by mass spectrometry and analytical ultracentrifugation

We identified a noncovalent trimer of Sirurus asotus roe lectin (SAL) at Mr 95,362 along with its monomer at M(r) 31,750 by electrospray ionization mass spectrometry when SAL was dissolved in 0.5% acetic acid, sprayed into the ion source with methanol as a sheath liquid, and desolvated at 75 degrees C in a heated capillary column. The molecular weight of SAL, determined by the sedimentation equilibrium method, was 95,200 and the sedimentation coefficient (S20,w) of SAL in water was 5.58. SAL existed as a noncovalent trimer in solution and showed the ability to agglutinate rabbit erythrocytes. SAL showed three peaks (sal 1, sal 2, and sal 3) by C8 reverse-phase HPLC, and these appeared to be a monomer, a dimer, and a trimer, respectively, by matrix-assisted laser desorption ionization-time of flight mass spectrometry, sal 1 and sal 2 were shown to have a structure interchangeable with that of sal 3 in water.

Presence of Turner stigmata in a case of dysgenetic male pseudohermaphroditism with 45,X/46,X+mar karyotype

A case is reported of dysgenetic male pseudohermaphroditism (DMPH) having Turner stigmata and 45,X/46,X+mar karyotype. The marker chromosome of this patient consisted of most if not all of the short arm, including the sex determining region of the Y chromosome. Although this karyotype is relatively common in Turner's syndrome and occasionally observed in mixed gonadal dysgenesis, DMPH is usually exemplified by a 46,XY karyotype except for one patient reported with 45,X/46,XY mosaicism. Turner stigmata have not previously been reported in DMPH. The present patient is an intermediate case between mixed gonodal dysgenesis and typical DMPH, and this indicates that 45,X/ 46,X +mar karyotype abnormality can result in a wide range of phenotype such as DMPH, mixed gonodal dysgenesis and Turner's syndrome.

[Epidural anesthesia for herniorrhaphy in a patient with severe dilated cardiomyopathy (DCM) under pimobendan control]

A 60-year-old man with severe DCM was scheduled for a herniorrhaphy under epidural anesthesia using fentanyl. Three months prior to operation, the patient suffered heart failure associated with life-threatening ventricular arrhythmia. The former was successfully treated with pimobendan as the main constituent of medication, but the latter was not responsive to various antiarrhythmic drugs with the exception of aprindine. On the day of operation and for two days postoperatively, pimobendan was administered daily. A sudden drop in systemic blood pressure and central venous pressure (CVP) during anesthesia, as well as the tendency to hypotensive status in the postoperative period were well regulated with continuous infusion of dopamine and dobutamine via CVP catheter probably due to the effect of up-regulation of pimobendan, together with adjustment of the volume of intravenous fluids. No dangerous ventricular arrhythmia were observed. Thereafter the patient made uneventful progress and was discharged on the 8th postoperative day.

Transient sick sinus syndrome associated with immunoblastic lymphadenopathy

We describe a very rare case of immunoblastic lymphadenopathy (IBL) accompanied with a sick sinus syndrome (SSS) in a 64-year-old male. SSS presented with progression of the IBL and subsided with improvement of the IBL following high dose prednisolone (PSL) therapy. The clinical course of this patient strongly suggested cardiac involvement in IBL and being the cause of the transient SSS. To our knowledge, this is the first case of IBL demonstrating SSS as a possible complication of the disease. This case may provide further information for the treatment of similar patients with IBL.

[Sensitivity loss in short wavelength sensitive cones in myopic eyes]

To investigate early changes of visual function in high myopic eyes, the relative sensitivity of the short-wavelength sensitive cones (s-cones) was measured by flash-evoked cortical potentials and electroretinograms and their relation with refractive error and axial length of the eyes was studied. A Ganzfeld stimulus was employed. The subjects were all under 37 years of age and were divided into 3 groups according to the magnitude of the refractive error as follows; 1) emmetropia/low myopia group (10 eyes), between +0.50 D and -3.00 D; 2) medium myopia group (8 eyes), between -3.25 D and -6.00 D; and 3) high myopia group (10 eyes), over -6.25 D. Their corrected visual acuities were better than 1.0 and their color vision was normal according to Panel D-15 and SPPII. They had no other ophthalmological abnormalities except tigroid fundus. The s-cone sensitivity was significantly correlated with the refractive error and axial length (p < 0.001) and was reduced prior to ophthalmoscopic retinal changes in the medium and high myopia groups. This indicates that the site of s-cone sensitivity loss in myopia is in the retinal.

Optical resolution of phenylthiohydantoin-amino acids by capillary electrophoresis and identification of the phenylthiohydantoin-D-amino acid residue of [D-Ala2]-methionine enkephalin

This is an initial report to propose a protein sequence analysis system with DL differentiation using capillary electrophoresis (CE). This system consists of a protein sequencer and a CE system. After fractionation of phenyl-thiohydantoin (PTH)-amino acids using a protein sequencer, optical resolution for each PTH-amino acid is performed by CE using some chiral selectors such as digitonin, beta-escin and others. As a model peptide, [D-Ala2]-methionine enkephalin (L-Tyr-D-Ala-Gly-L-Phe-L-Met), was used and the sequence with DL differentiation was determined, with the exception of the fourth amino acid, L-Phe, using our proposed system.

An assessment of pain and return to normal activity. Laparoscopic herniorrhaphy vs open tension-free Lichtenstein repair

BACKGROUND

Laparoscopic herniorrhaphy is controversial and deserves critical evaluation.

METHODS

In a randomized prospective study transabdominal preperitoneal laparoscopic herniorrhaphy (n = 24) was compared in patients to the tension-free Lichtenstein repair (n = 29) utilizing validated and reliable pain and activity assessment tools. The Sickness Impact Profile (SIP) was used to compare preoperative normal activity to postoperative activity. A Pain-O-Meter (visual analogue scale plus affective and sensory pain descriptors) assessed intensity of pain. The total pain assessment score and SIP were compared across time (postoperative day 1-42). Analgesic medication was used as a covariate.

RESULTS

The total pain score was less for laparoscopic herniorrhaphy but this did not reach statistical significance. Similarly, the SIP showed modest improvement for laparoscopic herniorrhaphy. No differences between groups were noted for morphine equivalents of administered analgesics or length of hospitalization.

CONCLUSION

Further investigation of laparoscopic herniorrhaphy is warranted.

mtDNA polymorphism in East Asian Populations, with special reference to the peopling of Japan

Nucleotide sequences of the major noncoding (D-loop) region of human mtDNA from five East Asian populations including mainland Japanese, Ainu, Ryukyuans, Koreans, and Chinese were analyzed. On the basis of a comparison of 482-bp sequences in 293 East Asians, 207 different sequence types were observed. Of these, 189 were unique to their respective populations, whereas 18 were shared between two or three populations. Among the shared types, eight were found in common between the mainland Japanese and Koreans, which is the largest number in the comparison. The intergenic COII/tRNA(Lys) 9-bp deletion was observed in every East Asian population with varying frequencies. The D-loop sequence variation suggests that the deletion event occurred only once in the ancestry of East Asians. Phylogenetic analysis revealed that East Asian lineages were classified into at least 18 monophyletic clusters, though lineages from the five populations were completely intermingled in the phylogenetic tree. However, we assigned 14 of the 18 clusters for their specificity on the basis of the population from which the maximum number of individuals in each cluster was derived. Of note is the finding that 50% of the mainland Japanese had continental specificity in which Chinese or Koreans were dominant, while < 20% of either Ryukyuans or Ainu possessed continental specificity. Phylogenetic analysis of the entire human population revealed the closest genetic affinity between the mainland Japanese and Koreans. Thus, the results of this study are compatible with the hybridization model on the origin of modern Japanese. It is suggested that approximately 65% of the gene pool in mainland Japanese was derived from the continental gene flow after the Yayoi Age.

Molecular and functional properties of cytochrome c from adult Ascaris suum muscle

Mitochondrial cytochrome c was isolated at high purity from adult Ascaris suum muscle and its molecular properties were investigated. The molecular weight of A. suum cytochrome c was determined to be 13,119 by electrospray ionization mass spectrometry. The oxidation-reduction potential of nematode cytochrome c was measured to be +248 mV; this value is comparable to those for cytochrome c from mammalian sources. The A. suum cytochrome c, like bovine heart cytochrome c, showed biphasic kinetics against bovine heart cytochrome c oxidase. Comparative kinetic studies revealed species-specificity in the reaction between cytochrome c and cytochrome c oxidase from A. suum and bovine sources. The cytochrome c content in mitochondria was highest at the second larval stage, in which the respiratory chain is the most aerobic among various developmental stages of A. suum. These data clearly show that adult A. suum cytochrome c, as isolated, is a bona fide substrate for cytochrome c oxidase in the aerobic respiratory chain of second-stage larvae.

Sensitive detection of near-infrared fluorescent dyes using high-performance liquid chromatography with peroxyoxalate chemiluminescence detection system

The highly sensitive detection of four near-infrared (near-IR) fluorescent dyes, methylene blue, pyridine 1, oxazine 1 and 3,3'-diethylthiadicarbocyanine iodide (DTDCI) by high-performance liquid chromatography (HPLC) with post-column peroxyoxalate chemiluminescence (PO-CL) detection utilizing bis(4-nitro-2-(3, 6,9-trioxadecyloxycarbonyl)phenyl) oxalate (TDPO) and hydrogen peroxide was examined. The detection limits for methylene blue, pyridine 1, oxazine 1 and DTDCI were 120, 27, 31, 0.19 fmol on-column at a signal-to-noise ratio of 2, respectively. The sensitivity for DTDCI was 250 times that obtained by HPLC with the conventional fluorescent detection.

Determination of the 8-methyl ether of xanthurenic acid in human serum by high-performance liquid chromatography with fluorescence detection

We developed a simple and sensitive assay for the 8-methyl ether of xanthurenic acid in serum by high-performance liquid chromatography with fluorescence detection (excitation at 340 nm, emission at 450 nm). The compound under study in serum samples was extracted with Sep-Pak C18 cartridge and the extract was applied to an octadecylsilane-bonded column (Nucleosil 5C18, 150 x 4 mm I.D.). The mobile phase used was a mixture of 0.05 M sodium acetate buffer (pH 6.0), containing 5 mM sodium 1-octanesulfonate and 0.1 mM Na2EDTA, and acetonitrile (93:7, v/v). The 8-methyl ether of xanthurenic acid from serum samples was sufficiently separated to be clearly distinguishable. The quantification limit was 2 x 10(-14) mol, which was sensitive enough to detect 8-methyl ether of xanthurenic acid in serum from normal subjects. The method was applied to samples from patients with deficiency in tryptophan metabolism, xanthurenic acid/3-hydroxy kynurenineuria and showed a striking elevation in serum 8-methyl ether of xanthurenic acid.

Studies on the mechanism of early onset macular degeneration in cynomolgus monkeys. II. Suppression of metallothionein synthesis in the retina in oxidative stress

Initial investigations done in this laboratory detected increased albumin and decreased glyceraldehyde 3-phosphate dehydrogenase concentrations in the retina of an animal model manifesting early onset macular degeneration. Both glyceraldehyde 3-phosphate dehydrogenase and albumin are markers of oxidative stress in cells. In this study, we used the same animal model to study further biochemical and physiological processes which may be involved in the pathogenesis of early onset macular degeneration in monkeys. We detected 60% lower catalase and glutathione peroxidase activities in the affected retinas suggesting lower antioxidant activities and oxidative stress. One of the consequences of oxidative stress is the production of metallothionein, a low molecular weight protein also induced by high concentrations of heavy metals such as zinc. Metallothionein was detected by RT-PCR in these monkey retinas. However initial quantitative PCR studies on this protein showed that the synthesis of metallothionein in affected retinas appears to be less than in normal controls. The affected retinas also showed a fourfold lower zinc concentration compared with the normal controls. No significant difference, however, could be detected in the zinc concentrations in plasma samples. Since induction of metallothionein synthesis is mediated by transcription factors which require heavy metals such as zinc for binding to specific sites in the DNA, the lowered zinc concentration may, thus, correlate with the lowered metallothionein expression. And since metallothionein is suggested to function as a free radical scavenger, the lowered metallothionein synthesis may consequently contribute to increased peroxidation reactions in the affected retinas. It appears therefore, that oxidative stress and the decreased metallothionein synthesis may be involved in the pathogenesis of early onset macular degeneration in this animal model.

Studies on the mechanism of early onset macular degeneration in cynomolgus (Macaca fascicularis) monkeys. I. Abnormal concentrations of two proteins in the retina

Cynomolgus (Macaca fascicularis) monkeys from three families, which showed symptoms of early onset macular degeneration was studied. Two proteins, albumin and glyceraldehyde 3-phosphate dehydrogenase, were found to have markedly altered concentrations in whole retina of the monkeys with early onset macular degeneration, compared with normal controls. SDS-polyacrylamide gel patterns detected a 40-70% increase in the concentration of albumin and about 65% decrease in the concentration of glyceraldehyde 3-phosphate dehydrogenase in these affected retinas. There was however no significant difference in the relative concentrations of albumin in the plasma samples of affected and normal monkeys belonging to the three families studied and to an unrelated family. These initial findings suggest that degradative as well as antioxidant enzymes might be involved in the mechanisms leading to macular degeneration. In addition, the results also correlate with a possible role of these two proteins in H2O2 toxicity and appear to indicate that oxidative stress is significant in the etiology of early onset macular degeneration.

Color-coded pattern suppresses visual evoked cortical potentials and electroretinograms

We developed a new visual stimulating system for recording visual evoked cortical potentials and electroretinograms. The stimulus was a color checkerboard, in which each check kept its chromaticity but changed its luminance with its corresponding check. Color-coded pattern stimuli using red and green checks did not produce visual evoked cortical potentials, while yellow checks produced clear responses in a normal subject. Moreover, five color stairs from red and green to yellow showed only that the more colors are different, the smaller the visual evoked cortical potentials become. In addition electroretinogram recordings indicated that color-coded patterns behave in the same way as in visual evoked cortical potentials. The mechanism that causes the small color visual evoked cortical potentials may already be present in the retina. Color perception may be able to induce a suppression of responses for luminance contrast that appears to be formed already in the retina. Retinal responses were affected whether the stimulus field was color coded or not. Pattern electroretinograms appear to be more than the sum of local on and off responses.

[Clinical and electrophysiological studies on posterior retinitis pigmentosa]

On the basis of fundus appearance and angiographic fundus pictures, 48 cases of posterior retinitis pigmentosa were divided into pericentral type (20 cases), perimacular type (21 cases), and macular type (7 cases). We compared the 3 groups clinically and electrophysiologically. Visual acuity and visual field were progressively deteriorated in half of the cases of pericentral type two years after the initial visit. The waveform of flash electroretinogram (ERG) was negative in the pericentral type, subnormal in the perimacular type, and normal in the macular type. These ERG findings suggest that the rod function was more severely damaged in the pericentral type than in the other types. Contrary to the ERG findings, the pattern-evoked cortical potential was normal in the pericentral type, and we assumed there is less damage of the foveal function in the pericentral type.

Hereditary spherocytic anemia with deletion of the short arm of chromosome 8

We describe a 30-month-old boy with multiple anomalies and mental retardation with hereditary spherocytic anemia. His karyotype was 46,XY,del(8)(p11.23p21.1). Genes for ankyrin and glutathione reductase (GSR) were localized to chromosome areas 8p11.2 and 8p21.1, respectively. Six patients with spherocytic anemia and interstitial deletion of 8p- have been reported. In these patients, severe mental retardation and multiple anomalies are common findings. This is a new contiguous gene syndrome. Lux et al. [1990: Nature 345:736-739] established that ankyrin deficiency and associated deficiencies of spectrin and protein 4.2 were responsible for spherocytosis in this syndrome. We reviewed the manifestations of this syndrome. Patients with spherocytic anemia and multiple congenital anomalies should be investigated by high-resolution chromosomal means to differentiate this syndrome.

[A HBV carrier with fulminant hepatitis complicated by ATL, multiple myeloma and thyroid cancer]

A 75-year-old female, born in Tochigi Prefecture, was admitted because of lumbago in August of 1991. The leukocyte count was 11,800/microliters with 22.5% atypical lymphocytes. We demonstrated a lymphocyte surface marker, ATL-associated antigen, and proviral DNA. We also identified 2.60 g/dl of serum monoclonal protein, found to be IgG, lambda type, and punched out lesions in the skull. We made a diagnosis of ATL. She was also a HBV carrier. The patient was treated with a modification of CHOP therapy, because of increasing atypical lymphocytes in the peripheral blood in November of 1992. She died of acute hepatitis, suddenly, in March of 1993. Autopsy revealed multiple myeloma, fulminant hepatitis and occult thyroid cancer in addition to ATL.

[Ecological treatment of bacterial vaginosis]

Ecological treatment of bacterial vaginosis with a Lactobacillus (yoghurt) was studied, and the following results were obtained. 1. A total of 11 women aged 20 to 60 with bacterial vaginosis were treated with intravaginal application of 5 ml of commercial yoghurt (pH 4.3 +/- 0.2). The effect of the treatment was evaluated 3 days after administration by monitoring the vaginal discharge and bacteriological assessment. 2. The clinical improvement was evaluated and the decreases of vaginal discharge and vaginal redness were significant and vaginal pH was lowered significantly also (P < 0.05). In the vaginal discharge 29 strains of bacteria were detected, but 3 days after administration, all 14 strains of Gram-negative bacteria disappeared. As for the overall bacteriological effects, 6/11 cases (54.5%) were eradicated. 3 cases were partly eradicated, 2 cases were replaced. These findings indicated that the Lactobacillus therapy was effective in both clinical and bacteriological responses.