[An adult case of recurrent myelopathy presenting with monoplegia following asthmatic attacks]

A 22-year-old woman noticed an acute onset muscle weakness in her right leg after an asthmatic attack. A neurological examination showed moderate muscle weakness from the right iliopsoas muscle to the toe muscles, a decreased deep tendon reflex in her right lower limb and mild hypesthesia in her right L2-S1 segments. Needle EMG revealed fibrillation potentials in the right gastrocnemius muscle and a positive sharp wave in the right anterior tibialis muscle. The findings of motor nerve conduction studies and sensory nerve conduction studies were normal. The lesion was considered to be located at the posterior horns, as well as at the anterior horns at the L2-S1 levels and also at their roots on the right side. The anterior horn cells appeared to be the most severely affected. Polio-, echo-, entero- and coxsackie-virus antibody titers showed no significant changes on the 36th and 64th days of the disease. The serum IgE level was elevated and mite antigen-specific IgE was strongly positive. MRI revealed no abnormalities in either the thoracic or lumbar spinal cord. Although the sensory disturbance did rapidly improve after corticosteroid therapy, no improvement was seen in her muscle weakness which thus resulted in the atrophy of the affected muscle. While undergoing the corticosteroid therapy, she suffered another asthmatic attack. Nine days after the second attack, she further developed weakness in her right deltoid, biceps brachii, triceps brachii, wrist extensor, wrist flexor, digits extensor and digits flexor muscles with hyperreflexia in her left upper limb. Cervical MRI disclosed a high intensity area at the C3-6 level on the T2-weighted images and also a gadolinium enhancement of the lesion. Since monoplegia had appeared twice previously after bronchial asthma attacks in this case, Hopkins syndrome was suggested. Hopkins syndrome has so far been exclusively reported in children, and no recurrent cases have ever been reported with this condition. This is therefore considered to be the first case of Hopkins syndrome occurring in an adult and also demonstrating recurrence.

[A case of familial type IIa hypercholesterolemia with the clinical features similar to cerebrotendinous xanthomatosis]

A 63-years-old woman noticed unsteady gait at the age of 56 years and then developed dysarthria two years later. A general physical examination at age 56 revealed mild hypertrophy of both Achilles tendons. On neurological examination, she had scanning speech, moderate limb and truncal ataxia, and moderate hyperreflexia of all limbs. A soft tissue X-ray examination disclosed hypertrophy of both Achilles tendons with multiple punctate calcification. Brain MRI showed diffuse cerebellar atrophy. Motor evoked potentials in the right limb disclosed a prolonged central conduction time. Blood chemistry showed familial type IIa hypercholesterolemia (cholesterol 320 mg/dl, and LDL-cholesterol 245 mg/dl), yet cholestanol level was normal. A examination of CTX gene mutation at hot spots revealed no mutation. Her mother and two siblings also had hypertrophy of Achilles tendons as well as type IIa hypercholesterolemia. In addition, the one sibling showed mild ataxia of lower limbs, respectively. This report suggests a possible link between familial type IIa hypercholesterolemia and cerebellar degeneration syndrome clinically mimicking CTX.

Hyperglycemia contributes insulin resistance in hepatic and adipose tissue but not skeletal muscle of ZDF rats

To determine the contribution of hyperglycemia to the insulin resistance in various insulin-sensitive tissues of Zucker diabetic fatty (ZDF) rats, T-1095, an oral sodium-dependent glucose transporter (SGLT) inhibitor, was administered by being mixed into food. Long-term treatment with T-1095 lowered both fed and fasting blood glucose levels to near normal ranges. A hyperinsulinemic euglycemic clamp study that was performed after 4 wk of T-1095 treatment demonstrated partial recovery of the reduced glucose infusion rate (GIR) in the T-1095-treated group. In the livers of T-1095-treated ZDF rats, hepatic glucose production rate (HGP) and glucose utilization rate (GUR) showed marked recovery, with almost complete normalization of reduced glucokinase/glucose-6-phosphatase (G-6-Pase) activities ratio. In adipose tissues, decreased GUR was also shown to be significantly improved with a normalization of insulin-induced GLUT-4 translocation. In contrast, in skeletal muscles, the reduced GUR was not significantly improved in response to amelioration of hyperglycemia by T-1095 treatment. These results suggest that the contribution of hyperglycemia to insulin resistance in ZDF rats is very high in the liver and considerably elevated in adipose tissues, although it is very low in skeletal muscle.

[A case of neuro-Behçet's disease presenting as chronic progressive cerebellar ataxia]

A case of neuro-Behçet's disease manifested as chronic progressive cerebellar ataxia is reported. A 56-year-old woman had suffered from recurrent oral aphthous ulcers, genital ulcers and polyarthritis since her late twenties. At age 53, she noticed small stepped-gait; at age 55, she developed scanning speech, a wide-based gait and memory disturbance. On admission she had oral aphthous ulcers, scarring of genital ulcers and polyarthralgia. A neurological examination revealed memory disturbance, saccadic eye movement, scanning speech, a slow tongue wiggle, moderate limb and truncal ataxia and moderate hyperreflexia in four limbs without pathological reflexes. Relevant laboratory examination data showed a positive HLA-B51. The cerebrospinal fluid (CSF) had a mild elevation of the cell counts and the amounts of protein. Brain magnetic resonance imaging showed mild atrophy of the cerebellum and brainstem. Fluoro-2-deoxyglucose-positron emission tomography showed a decreased glucose metabolism in the cerebellum and brainstem. Methylprednisolone pulse therapy (1 g x 3 days) followed by oral corticosteroids (50 mg/day) with gradual tapering markedly alleviated the cerebellar ataxia. The presence of oral and genital ulcers and CSF pleocytosis as well as effectiveness of corticosteroids in relieving the neurologic symptoms suggested neuro-Behçet's disease. We propose the existence of a new subtype of neuro-Behçet's disease characterized by chronic progressive cerebellar involvement possibly due to microvasculitis for which corticosteroids may be effective.

Effects of stimulus orientation on spatial frequency function of the visual evoked potential

Visual performance is better in response to vertical and horizontal stimuli than oblique ones in many visual tasks; this is called the orientation effect. In order to elucidate the electrophysiological basis of this psychophysical effect, we studied the effects of stimulus orientation on the amplitudes and latencies of visual evoked potentials (VEPs) over different spatial frequencies of the visual stimulation. VEPs to sinusoidal gratings at four orientations (vertical, horizontal, and oblique at 45 degrees and 135 degrees) with eight spatial frequencies (0.5-10.7 cycles/deg) at reversal rates of 1 Hz and 4 Hz were recorded in nine subjects. At 1-Hz stimulation, the amplitude and latency of P100 were measured. At 4-Hz stimulation, VEPs were Fourier-analyzed to obtain phase and amplitude of the second harmonic response (2F). At 1-Hz stimulation, P100 latencies were decreased for oblique stimuli compared with those for horizontal and vertical stimuli at lower spatial frequencies. Conversely, those for oblique stimuli were increased compared with those for horizontal and vertical stimuli at higher spatial frequencies. At 4-Hz stimulation, spatial tuning observed in 2F amplitude of the oblique gratings shifted to lower spatial frequencies when compared with those of vertical stimulation. The alteration of the VEP spatial frequency function caused by the oblique stimuli was in good agreement with the orientation effect observed in psychophysical studies. Our study may have a clinical implication in that VEP testing with stimuli in more than one orientation at slow and fast temporal modulations can be useful in evaluating neurological disease affecting the visual system.

Membrane properties of archaeal macrocyclic diether phospholipids

Several biophysical properties of four synthetic archaeal phospholipids [one polyprenyl macrocyclic lipid A and three polyprenyl double-chain lipids (B, C, D) bearing zero, one or four double bonds in each chain] were studied using differential scanning calorimetry, electron and optical microscopies, stopped-flow/light scattering and solid-state 2H-NMR techniques. These phospholipids gave a variety of self-organized structures in water, in particular vesicles and tubules. These assemblies change in response to simple thermal convection. Some specific membrane properties of these archaeal phospholipids were observed: They are in a liquid-crystalline state over a wide temperature range; the dynamics of their polyprenyl chains is higher than that of n-acyl chains; the water permeability of the membranes is lower than that of n-acyl phospholipid membranes. It was also found that macrocyclization remarkably improves the barrier properties to water and the membrane stability. This may be related to the adaptation of Methanococcus jannaschii to the extreme conditions of the deep-sea hydrothermal vents.

A case of aortic dissection with transient ST-segment elevation due to functional left main coronary artery obstruction

A 48-year-old man with a history of hypertension and diabetes mellitus was hospitalized with sudden onset of severe chest pain. He was in cardiogenic shock with a systolic pressure of 60 mm Hg. His electrocardiogram (ECG) showed ST-segment elevation in the precordial leads suggestive of acute anteroseptal myocardial infarction. The ST-segment returned to baseline after the systolic blood pressure rose to 100 mm Hg with the administration of sympathomimetic agents. Aortography and transesophageal echocardiography demonstrated type A aortic dissection and aortic regurgitation. Aortography and short-axis transesophageal echocardiography showed during diastole almost complete collapse of the true lumen of the ascending aorta caused by the intimal flap. The patient underwent surgical repair of the aortic dissection and implantation of Palmaz stents in the carotid arteries. Decreased blood pressure and the presence of aortic regurgitation accelerated the collapse of the true lumen during diastole in the ascending aorta, resulting in functional obstruction of the left main coronary artery, which may have been related to ST-segment changes in this case.

Deep venous thrombosis and pulmonary thromboembolism associated with a huge uterine myoma--a case report

A 51-year-old woman with a large uterine myoma suffered from acute pulmonary thromboembolism. Venography revealed thrombosis in the right common iliac vein and almost complete obstruction of the left common iliac vein. The ascending lumbar vein showed collateral drainage. Treatment was initiated with continuous intravenous heparin sodium, and a Greenfield filter was inserted to prevent the extension of the pulmonary embolism during and after hysterectomy. After a total hysterectomy, venography revealed restoration of patency in the bilateral common iliac veins, and no flow was seen in the ascending lumbar vein. Thorough clinical examinations failed to identify any other prothrombotic conditions. These results suggest that a large uterine myoma compressed veins in the pelvis, and the resulting impaired blood flow caused deep venous thrombosis and pulmonary thromboembolism.

Methicillin-resistant Staphylococcus aureus (MRSA) isolated at Fukuoka University Hospital and hospitals and clinics in the Fukuoka city area

Bacteriological and epidemiological studies were carried out on 106 isolates of methicillin-resistant Staphylococcus aureus (MRSA) isolated at our hospital (56 isolates) and from 15 other hospitals and clinics (50 isolates) in the Fukuoka city area. Strains were studied regarding coagulase-type, beta-lactamase production, and antimicrobial susceptibility; genotype studies used pulsed-field gel electrophoresis (PFGE) with cluster analysis. The majority of isolates produced coagulase type II (75.5%) and beta-lactamase (72. 6%); there was high susceptibility to arbekacin (84.9%) but no resistance to vancomycin. Dendrogram analysis of PFGE patterns identified five major clusters that generally correlated with coagulase-type and beta-lactamase production. Though isolates of two clusters were both coagulase type II and beta-lactamase producing, which was the most common circulating strain both in our hospital and other hospitals and clinics, dendrogram analysis of PFGE patterns showed that they were heterogeneous. Four genetically identical isolates from the same hospital suggested the existence of hospital-specific strains. Nine genetically identical isolates from intensive care units (ICU) in our hospital suggested that a unique strain of MRSA was found there. It had not been transmitted from another area. PFGE with cluster analysis seemed to be an essential tool to detect area-specific or hospital-specific strains undifferentiated by phenotyping. These findings confirmed that a combination of PFGE, including cluster analysis along with coagulase-type and beta-lactamase production may provide more detailed information for the epidemiological study of MRSA.

Increased chymase activity in internal thoracic artery of patients with hypercholesterolemia

Apart from ACE, various angiotensin II (Ang II)-forming serine proteinases (eg, chymase, kallikrein, and cathepsin G) are known to exist in human tissues, but their clinical significance or the regulatory mechanisms that control their activities are not well established. A recent clinical study has shown that chymase activity was significantly increased in human atherosclerotic or aneurysmal aorta. The association between vascular Ang II-forming activities (AIIFAs) in the human internal thoracic artery (ITA) and various clinical parameters was studied with the use of ITAs obtained from 32 patients who underwent coronary artery bypass graft surgery. Total and ACE- and chymase-dependent AIIFAs in homogenates of ITAs were determined. Total AIIFA was 8.67+/-0.86 (nmol Ang II formed. min(-1). mg protein(-1) [U]), and approximately 95% of the activities were due to chymase. Serum total cholesterol level, but no other risk factors, significantly correlated with chymase- (r=0. 60, P<0.001) and ACE- (r=0.35, P<0.05) dependent AIIFAs, respectively. LDL cholesterol level was also correlated with chymase-dependent AIIFAs (r=0.47, P<0.05). Mast cells identified through the use of toluidine blue or immunohistochemical staining appeared in the adventitia but not in the intima or media of ITAs. Our results suggest that an increased plasma LDL cholesterol level may induce increased arterial chymase and ACE activity.

A single amino acid deletion in the carboxy terminal of apolipoprotein A-I impairs lipid binding and cellular interaction

The carboxy-terminal region of apolipoprotein (apo) A-I has been shown by mutagenesis or synthetic peptides to play an important role in lipid binding. However, the precise functional domain of the C-terminal remains to be defined. In this study, apoA-I Nichinan, a naturally occurring human apoA-I variant with a deletion of glutamic acid 235, was expressed in Escherichia coli to examine the effect of this mutation on the functional domain of apoA-I for lipid binding and related consequences. A dimyristoyl phosphatidylcholine binding study with recombinant (r-) proapoA-I Nichinan showed a significantly slow initial rate of lipid binding. On preincubation with human plasma lipoprotein fractions (d<1.225 g/mL) at 37 degrees C for 1 hour, (125)I-labeled normal r-proapoA-I was chromatographed as a single peak at the high density lipoprotein (HDL) fraction, whereas (125)I-labeled r-proapoA-I Nichinan was chromatographed into the HDL fraction as well as the free r-proapoA-I fraction (23% of radioactivity). Circular dichroism measurements showed that the alpha-helix content of lipid-bound r-proapoA-I Nichinan was reduced, being 62% (versus 73%) of normal r-proapoA-I. Nondenaturing gradient gel electrophoresis of reconstituted HDL particles assembled with r-proapoA-I Nichinan and normal r-proapoA-I showed similar particle size. To study cholesterol efflux, human skin fibroblasts were labeled with [(3)H]cholesterol, followed by incubation with either lipid-free r-proapoA-I or DMPC/r-proapoA-I complex. Fractional cholesterol efflux from [(3)H]cholesterol-labeled fibroblasts to lipid-free r-proapoA-I Nichinan or DMPC/r-proapoA-I Nichinan complexes was significantly reduced relative to that of normal r-proapoA-I or DMPC/r-proapoA-I during the 6-hour incubation. Binding assays of human skin fibroblasts by lipid-free r-proapoA-I showed that r-proapoA-I Nichinan was 32% less bound to fibroblasts than was normal r-proapoA-I. Our data demonstrate that the deletion of glutamic acid 235 at the C-terminus substantially reduces the lipid-binding properties of r-proapoA-I Nichinan, which may cause a reduction in its capacity to interact with plasma membranes as well as to promote cholesterol efflux from cultured fibroblasts.

[A case of diabetic polyneuropathy complicated with entrapment neuropathy of the bilateral ulnar nerves due to osteoarthrosis at the elbow]

We report a 61-year-old man with diabetic polyneuropathy and bilateral ulnar nerve palsy due to osteoarthrosis in the elbow. He was diagnosed as having non-insulin dependent diabetes mellitus (DM) at 40 years of age. At 56 years of age, he developed muscle atrophy and weakness predominantly in the distal parts of his upper limbs. A neurological examination showed him to have severe atrophy and weakness in the muscles innervated by the ulnar nerve bilaterally. He also had paresthesia on the distal parts of all four limbs. Superficial and deep sensory deficits were observed in the lower limbs. A motor nerve conduction study showed a marked reduction in the motor conduction velocity as well as in the amplitude of the action potentials of both ulnar nerves. Roentgenograms of the elbow joints and grooves for the ulnar nerve revealed marked osteophyte formation bilaterally. The bilateral ulnar nerve palsy was thus considered to be due to the entrapment of the nerve by the osteophyte. Since several studies have suggested the existence of a relationship between DM and osteoarthropathy, it is important to check for the possible presence of osteoarthrosis in cases of diabetic neuropathy complicated with entrapment neuropathy.

Hyperglycemia impairs the insulin signaling step between PI 3-kinase and Akt/PKB activations in ZDF rat liver

Akt/PKB activation is reportedly essential for insulin-induced glucose metabolism in the liver. During the hypoinsulinemic and hyperglycemic phase in the Zucker diabetic fatty (ZDF) rat liver, insulin-induced phosphorylations of the insulin receptor (IR) and insulin receptor substrate (IRS)-1/2 were significantly enhanced. Similarly, phosphatidylinositol (PI) 3-kinase activities associated with IRS-1/2 were markedly increased in ZDF rat liver compared with those in the control lean rat liver. However, interestingly, insulin-induced phosphorylation and kinase activation of Akt/PKB were severely suppressed. The restoration of normoglycemia by sodium-dependent glucose transporter (SGLT) inhibitor to ZDF rats normalized elevated PI 3-kinase activation and phosphorylation of IR and IRS-1/2 to lean control rat levels. In addition, impaired insulin-induced Akt/PKB activation was also normalized. These results suggest that chronic hyperglycemia reduces the efficiency of the activation step from PI 3-kinase to Akt/PKB kinase and that this impairment is the molecular mechanism underlying hyperglycemia-induced insulin resistance in the liver.

[A Japanese case of Poland-Möbius syndrome]

We herein report a Japanese case of Poland-Möbius syndrome. The patient was a 19-year-old female. She was the product of a full-term forceps delivery. Birth weight was 2500 g. She had a defect of the right pectoral muscle, and syndactyly of the right hand. When she was 10 days old, facial diplegia, bilateral abducens nerve palsy, and bilateral ptosis were also noted. She was admitted to our hospital at 19 years of age. On physical examination, she had microsyndactyly of the right hand, and her right pectoralis major muscle was absent. Neurological examination revealed bilateral abducens nerve paresis, mild impairement of the upward and adducting movement of both eyes and bilateral facial weakness and atrophy of the left side of her tongue. Her karyotype was normal. Neither R 1 nor R 2 response was evoked in the blink reflex on either side. Brain MRI disclosed thin facial nerves and atrophy of the pons and medulla. Therefore, she was diagnosed as a case of Poland-Möbius syndrome. In this case, the facial nerves were considered to be hypoplastic.

Zonal heterogeneity in action of angiotensin-converting enzyme inhibitor on renal microcirculation: role of intrarenal bradykinin

The present study examined the role of intrarenal bradykinin in angiotensin-converting enzyme inhibitor (ACEI)-induced dilation of renal afferent (AFF) and efferent arterioles (EFF) in vivo, and further evaluated whether ACEI-stimulated bradykinin activity differed in superficial (SP) and juxtamedullary nephrons (JM). Arterioles of canine kidneys were visualized with an intravital charge-coupled device camera microscope. E4177 (an angiotensin receptor antagonist, 30 microg/kg) dilated AFF and EFF in SP (15 +/- 3% and 19 +/- 5%) and JM (15 +/- 3% and 18 +/- 4%). Subsequently, cilazaprilat (30 microg/kg) caused further dilation of both AFF (29 +/- 4%) and EFF (36 +/- 4%) in JM, whereas in SP it dilated only EFF (29 +/-3%). Similarly, in the presence of E4177, cilazaprilat caused further increases in sodium excretion. This cilazaprilat-induced vasodilation and natriuresis was abolished by a bradykinin antagonist (N(alpha)-adamantaneacetyl-D-Arg-[Hyp3,Thi5,8,D-Phe7]b radykinin). In parallel with these results, cilazaprilat increased renal bradykinin content, more greatly in the medulla than in the cortex (5.7 +/- 0.4 versus 4.6 +/- 0.1 ng/g). Similarly, cilazaprilat elicited greater bradykinin-dependent increases of nitrite/nitrate in the medulla. In conclusion, zonal heterogeneity in renal bradykinin/nitric oxide levels and segmental differences in reactivity to bradykinin contribute to the diverse responsiveness of renal AFF and EFF to ACEI. ACEI-enhanced kinin action would participate in the amelioration of glomerular hemodynamics and renal sodium excretion by ACEI.

Hyperinsulinemic hypoalphalipoproteinemia as a new indicator for coronary heart disease

OBJECTIVES

The purpose of this study was to investigate the association among insulin resistance, high density lipoprotein cholesterol (HDL-C) and coronary heart disease (CHD), and to test the hypothesis that HDL-C may ameliorate the adverse effects of insulin.

BACKGROUND

Serum low HDL-C (hypoalphalipoproteinemia) and hyperinsulinemia are independent predictors for CHD, but a strong negative correlation exists between them, as in patients with syndrome X.

METHODS

Fifty-four pairs of cases (M/F: 49/5), defined as patients with angiographically proved CHD, and control subjects (M/F: 49/5) matched with cases with regard to gender and age were included. Insulin resistance was assessed by the homeostasis model assessment (HOMA).

RESULTS

Cases had increased HOMA insulin resistance and lower serum levels of HDL-C than controls. A receiver operating characteristic (ROC) curve analysis indicated that HDL-C and insulin resistance were significant discriminators of CHD (area under ROC curve: 0.72 and 0.69, respectively). The interaction between HDL-C and the association of insulin resistance with CHD was significant: subjects with hyperinsulinemia and high HDL-C had no increased risk of CHD. Multivariate conditional logistic regression analysis showed that hyperinsulinemic hypoalphalipoproteinemia was a stronger indicator for CHD than either HDL-C or insulin resistance alone (-2 log likelihood: 19.0 vs. 12.6 or 15.7).

CONCLUSIONS

Hyperinsulinemic hypoalphalipoproteinemia was a more potent indicator for CHD than either insulin resistance or low serum HDL-C levels alone, and the adverse effects of hyperinsulinemia seem to be ameliorated by high HDL-C levels.

The effect of spatial frequency on chromatic and achromatic steady-state visual evoked potentials

OBJECTIVE

Little is known about the physiological properties of the major components of steady-state visual evoked potentials (VEPs). Based on the hypothesis that isoluminant color and high contrast pattern differentially activate the parvo- and magnocellular pathways, we studied difference in spatial frequency function between chromatic and achromatic VEPs to sinusoidal gratings.

METHODS

Steady-state VEPs to isoluminant chromatic (red-green) and high contrast (90%) achromatic (black-white) sinusoidal gratings with nine spatial frequencies (0.5 to 8.0 cycles/degrees (cpd)) at 4 Hz (8 reversals/s) were recorded in 13 normal subjects. VEPs were Fourier analyzed to obtain phase and amplitude of the second (2F) and fourth (4F) harmonic responses.

RESULTS

The 2F amplitude of chromatic VEPs decreased above 4.0 cpd in a low-pass function while that of achromatic VEPs showed a band-pass function with a peak at 4.0 cpd. The 4F amplitude of chromatic VEPs was not affected significantly by spatial frequency whereas that of achromatic VEPs exhibited a high-pass function. The phases of 2F and 4F showed a non-monotonic function of spatial frequency in both chromatic and achromatic stimuli with peaks at middle spatial frequencies.

CONCLUSION

Chromatic and achromatic visual stimuli differently affected 2F and 4F components, which thus suggests that 2F and 4F components are generated from different neuronal subgroups largely in the parvocellular pathway.

Structure of a kallikrein-like enzyme and its tissue localization in the dog

We previously purified a kallikrein-like enzyme from the dog heart and demonstrated that it is not only able to form kinins but can also convert angiotensin (Ang) I to Ang II. The aim of the present study was to clarify the structure and tissue localization of this enzyme. Western blot analysis of various canine tissues was performed with antiserum against the purified dog heart enzyme. The purified enzyme was subjected to a determination of its amino acid composition and a sequence analysis. Western blotting indicated that this enzyme was present in the heart, aorta, kidney, pancreas, lung, liver, spleen, small intestine, and skeletal muscle. The amino acid composition of the enzyme was different from that of dog urinary kallikrein. Amino acid sequence analysis indicated that it is likely to be N-terminally blocked. The present study showed that this kallikrein-like enzyme is different from previously reported kallikrein and is distributed not only in the heart, but also in other tissues such as the aorta, kidney, lung, liver, spleen, small intestine, and skeletal muscle. This enzyme may exert local effects by generating kinins and Ang II.