[Neuroimaging and electrophysiological study in epilepsy]

There exist various morphological and biochemical changes closely associated with electrophysiological phenomena which cause epileptic seizures in the brains of epilepsy patients. Recent developments in investigation methods, not only electrophysiological(EEG and MEG), but also neuroimaging involving morphological imaging(CT and conventional MRI) and functional imaging(SPECT, PET, functional MRI and MRS) is able to demonstrate these changes. SPECT and PET can particularly clarify the changes of cerebral blood flow and glucose metabolism between interictal and ictal periods. In our experience of 423 patients who underwent epilepsy surgery for intractable seizures, these interventions provide important information to identify the epileptogenic foci. However, in practice, discordance in the results of these presurgical evaluations is recognized, and invasive intracranial recordings are needed in such cases. These problems in diagnosis were shown especially in patients with mesial temporal sclerosis and focal cortical dysplasia. To detect an epileptogenic focus more clearly, a combination of morphological and functional findings, new functional imaging such as neurotransmitter receptor imaging, EEG-triggered or neuropharmacological functional MRI, as well as, statistical parametric analysis may be needed.

[Outcomes of home anti-cancer chemotherapy--estimation of hepatic arterial infusion chemotherapy for patients with multiple liver metastases]

A total of 18 patients (13: colon cancer, 5: gastric cancer) with multiple liver metastases (H3) underwent hepatic arterial infusion chemotherapy (HAI) using an implanted arterial port with portable syringe pumps in our outpatient clinic. Clinical perspective: overall response rate was 22.2% (CR: 1 case, PR: 3 cases (1 case: hepatectomy after HAI), NC: 12 cases, PD: 2 cases), however, 7 of 12 cases of NC were long NC (more than 6 months). No major complications with HAI were experienced. Patient Perspective: After HAI in our outpatient clinic, the 50% survival was 341 days, 50% hospital free days were 319 days and home stay rate was 92.9%. Societal Perspective: cost and hospital stay days were significantly reduced. Home anti-cancer chemotherapy using HAI for gastrointestinal cancer patients with multiple liver metastases was safe and efficient from the viewpoint of medical outcomes.

Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human

OBJECTIVE

To clarify how the primary sensorimotor and supplementary motor areas are involved in the generation of the rhythmicity of electromyogram (EMG) activity during continuous muscle contraction.

METHOD

We analyzed the coherence between subdurally recorded cortical electroencephalograms (EEG) and EMGs of the contralateral wrist extensor muscle during continuous isometric contraction in 8 patients with medically intractable epilepsy.

RESULTS

In all subjects, a significant coherence between the primary motor area (M1) and EMG was observed at the peak frequency of 15+/-3 Hz (means+/-SD). In the primary somatosensory area (S1) of 7 subjects and the supplementary motor area proper (SMA proper) of 4 subjects, significant coherence with EMG was observed at 12+/-5 and 15+/-4 Hz, respectively. The time lags revealed by cross-correlogram were 10+/-3, 7+/-1 and 22+/-8 ms in the M1, S1 and SMA proper, respectively, with the EMG lagging in all areas.

CONCLUSION

These findings suggest that the rhythmic activity in the SMA proper, as well as in the S1 and M1, is related to the generation of the rhythmicity of EMG activity.

Movement-related change of electrocorticographic activity in human supplementary motor area proper

We investigated movement-related change in the cortical EEG signal by simultaneous recording from the primary sensorimotor area (S1-M1) and the supplementary motor area proper (SMA proper) in four patients with intractable partial epilepsy. By the use of temporal spectral evolution (TSE) analysis, the change in background cortical activity in relation to self-paced finger/wrist extension was compared among the SMA proper, S1 and M1. All three areas showed a decrease in the amount of activity for the frequency range between 10 and 40 Hz before the onset of movement [event-related desynchronization (ERD)]. The SMA proper showed earlier onset of ERD for 18-22 Hz activity (-3.4 +/- 0.5 s, mean +/- standard deviation) than M1 (-1.7 +/- 0.7 s) and S1 (-1.4 +/- 0.5 s). The degree of ERD in S1 was greatest for 10-14 Hz and that in M1 for 18-22 Hz, whereas in the SMA proper ERD was observed throughout the frequency bands from 10 to 40 Hz. Neither the degree nor the onset time of ERD in the SMA proper was lateralized to either the ipsilateral or the contralateral side with respect to the movement. A transient increase in activity after movement [event-related synchronization (ERS)] was observed in all three areas. In the SMA proper, two out of four subjects showed ERS for frequency bands below 40 Hz with both ipsilateral and contralateral movements. By contrast, in S1 and M1, ERS was recorded for frequency bands between 20 and 90 Hz, and was predominantly associated with the contralateral movement. The present study suggests that the background cortical activity in the SMA proper has a specific temporal pattern with respect to self-paced movement, and that the SMA proper is involved in motor preparation earlier than S1-M1 in a bilaterally organized manner.

Absence of simple partial seizure in temporal lobe epilepsy: its diagnostic and prognostic significance

The diagnostic and prognostic significance of the absence of simple partial seizures (SPS) immediately preceding complex partial seizures (CPS) was examined in patients with temporal lobe epilepsy. The status of self-reported SPS in 193 patients with temporal lobe epilepsy who had surgical therapy more than 2 years ago was reviewed. Before surgery, 37 patients never experienced SPS before CPS (Group A), 156 patients either always or occasionally had SPS before CPS (Group B). The frequency of mesial temporal sclerosis (MTS) was lower and the age at onset of epilepsy was higher in Group A. The seizure focus was in the language-dominant temporal lobe in 73% of the cases in Group A, compared with 40% in Group B. The surgical outcome did not differ between the two groups. The findings suggest that temporal lobe seizures without preceding SPS tend to originate in the language-dominant temporal lobe that contains a pathologic etiology other than MTS, especially in the lateral temporal lobe. The surgical outcome in patients without SPS is similar to that in patients with SPS.

Peptidic immunosuppressants from the fungus Trichoderma polysporum

Three new 10-residue lipopeptaibols, trichopolyns III-V have been isolated from the fungus Trichoderma polysporum together with the known trichopolyns I and II. Structure determination has been achieved on the basis of spectroscopic and chemical evidence. These peptides have been shown to suppress the proliferation of lymphocytes in mouse allogeneic mixed lymphocyte reaction.

Electrical stimulation of the contralateral mesial temporal structure induces an ipsilateral seizure pattern in mesial temporal lobe epilepsy

PURPOSE

We examined the mode of seizure development induced by electrical stimulation in patients with mesial temporal lobe epilepsy.

METHODS

Of 25 patients undergoing intracranial EEG evaluation and electrical stimulation ipsilateral to the presumed site of habitual seizure origin, 17 patients had additional stimulation studies on the contralateral temporal lobe.

RESULTS

Fourteen of the 25 patients had seizures induced with ipsilateral stimulation, and two of the 17 patients had seizures with contralateral stimulation. Seizures induced by ipsilateral stimulation started in the ipsilateral temporal lobe, whereas those induced by contralateral stimulation originated from the ipsilateral temporal lobe structure and were identical to the habitual seizures.

CONCLUSIONS

Electrical stimulation of the temporal lobe structure opposite the site of habitual seizure origin is said to induce a seizure rarely. However, according to our preliminary results, if contralateral stimulation elicits a habitual seizure in the ipsilateral temporal lobe, it might be considered additional confirmatory evidence of seizure lateralization.

[Arg8]-vasopressin-induced increase in intracellular Ca2+ concentration in cultured rat hippocampal neurons

Changes in intracellular Ca2+ concentration ([Ca2+]i) induced by [Arg8]-vasopressin (AVP) were studied in cultured rat hippocampal neurons by fura-2 fluorometry. AVP (10-1,000 nM) caused a dose-dependent increase in [Ca2+]i. The selective V1 vasopressin receptor agonist [Phe2, Ile3, Orn8]-vasopressin also induced a significant increase in [Ca2+]i, whereas the selective V2 vasopressin receptor agonist [deamino Cys1, D-Arg8]-vasopressin showed no effect. The AVP-induced increase in [Ca2+]i was inhibited by the selective V1 vasopressin receptor antagonist d(CH2)5[Tyr2(Me), Arg8]-vasopressin and nonpeptide V1 antagonist OPC-21268. On the other hand, no antagonistic effects were observed with the V2 vasopressin antagonist desglycinamide-[d(CH2)5, D-Ile2, Ile4, Arg8]-vasopressin and nonpeptide V2 antagonist OPC-31260. The increase in [Ca2+]i induced by AVP was abolished after removal of extracellular Ca2+. In addition, AVP-induced [Ca2+]i elevation was not affected by treatment with verapamil, which blocked the [Ca2+]i increase induced by an isotonic high K(+)-medium (50 mM). However, omega-conotoxin GVIA completely inhibited the effect of AVP. These results suggested that the AVP-induced [Ca2+]i increase in cultured rat hippocampal neurons is due to influx of Ca2+ through V1 VP receptors coupled with N-type calcium channels.

Competitive adsorption between phospholipid and plasma protein on a phospholipid polymer surface

The competitive adsorption of proteins and phospholipids on omega-methacryloyloxyalkyl phosphorylcholine (MAPC) polymer was evaluated in this study. Albumin, fibrinogen, and dimyrstoyl phosphatidylcholine (DMPC) were used as model components. The amount of DMPC adsorbed on the MAPC polymers increased with an increase in the MAPC unit composition of the polymer. The methylene chain length of the MAPC unit was another factor influencing the DMPC adsorption when the MAPC unit composition of the MAPC polymer was low. The state of albumin and DMPC liposome adsorbed on the 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer was determined by dynamic contact angle (DCA) measurement. The adsorption strength of albumin on the MPC polymer was weaker than that on the poly[n-butyl methacrylate (BMA)], that is, the albumin was detached from the MPC polymer during the rinsing process. On the poly(BMA) surface, no difference in the shape of the DCA loops before and after contact with the DMPC liposomal suspension was observed. Fibrinogen adsorption on the MAPC polymer was detected by gold-colloid labeled immunoassay. The amount of fibrinogen adsorbed on every MAPC polymer surface was reduced by addition of the DMPC liposome in the fibrinogen solution. The number of platelets adhered on the MAPC polymer was also decreased when the DMPC liposome was present in the fibrinogen solution during pretreatment. We concluded that phospholipids were preferentially adsorbed on the MAPC polymer surface compared with plasma protein and that the adsorbed phospholipids played an important role in showing an excellent blood compatibility on the MAPC polymer.

Ictal paraphasia induced by language activity

Four patients with ictal speech disturbance were studied. Their seizures featured isolated, or series of, brief episodes of fluent paraphasia, paragraphia, and comprehension deficit. These episodes were often induced by language activity. Six patients with ictal paraphasia or paragraphia, as a recurrent habitual seizure, are reported in the literature. All ten cases, including the four cases described here and the six cases reported in the literature, featured patients who uttered meaningless speech fluently or displayed paragraphia. The syllables uttered during seizures contained many neologisms and resembled the neologistic jargon of patients with fluent aphasias of the Wernicke type. Nine patients had clusters or status of brief seizures and four patients had auditory hallucination as an ictal event. The seizures in six patients were easily induced by the use of language. Seizure focus was on the left side in all patients mentioned. The possibility of another type of language-induced seizures than those seen in reading epilepsy or language-induced epilepsy is suggested in which myoclonias of the jaw and face, or upper extremities are the main seizure types.

Awareness and responsiveness during partial seizures

We examined the impairment of consciousness during partial seizures (PS) arising from various brain sites according to the operational definition of the international classification, i.e., altered awareness and/or responsiveness. The subjects were 142 patients who underwent intracranial EEG evaluation and subsequent resective surgery. First, the patients were examined to determine whether they usually had been partially or completely aware of their seizures. Second, spontaneous habitual seizures that had been videotaped with simultaneous intracranial EEG recording were reviewed to determine responsiveness and recall during ictal behavioral alterations. In all, 114 patients were partially or completely aware of their seizures. Patients who tended not to be aware of their seizures were those with frontal lobe epilepsy (FLE) with extensive epileptogenic regions on the language nondominant side and those with temporal lobe epilepsy (TLE) with seizure origin in the lateral cortex of the language dominant side. Of the 21 patients with FLE, 88 with TLE, and 4 with occipital lobe epilepsy, 7, 22, and 2 patients responded to stimuli during the seizure, respectively, but only 11 of the patients with FLE and none of the other patients could recall the stimuli applied during the behavioral alterations. Bilateralization of seizure discharges correlated with impaired responsiveness. According to the International Classification, about half of patients with FLE had only simple partial seizures (SPS) and the other patients had complex partial seizures (CPS). Altered awareness and/or responsiveness occurred in most habitual partial seizures in our subjects. The term "complex" appears to be useful in clinical practice, although the contents of ictal behavior and the site or side of seizure origin are not implied.

Intraspecific variability of the tandem repeats in Nicotiana putrescine N-methyltransferases

The putrescine N-methyltransferase (PMT) cDNA clone previously isolated from tobacco encodes a spermidine synthase-like protein with an 11 amino acid element repeated four times in tandem at the amino terminus. Genomic Southern blot analyses indicated that this N-terminal repeat array is found in tobacco PMTs but absent in Hyoscyamus and Atropa PMTs. A truncated tobacco PMT in which this repeat array was entirely removed still retained full enzymatic activity when expressed in Escherichia coli. Three PMT genes (NsPMT1, NsPMT2, NsPMT3) isolated from Nicotiana sylvestris encode two, five, and nine tandem repeats, respectively, in the first exon, but otherwise encode highly conserved proteins. Analysis of PCR fragments amplified from the genomes of N. tabacum and its two probable progenitors shows that one of the nine repeat elements in NsPMT3 was precisely deleted in the corresponding N. tabacum gene. These results indicate that direct tandem repeats of a 33 bp sequence that encodes 11 amino acids of no obvious function were added to the ancestral Nicotiana PMT gene, and that the tandem repetition was genetically very unstable, contracting or expanding during evolution of the Nicotiana species.

Why do phospholipid polymers reduce protein adsorption?

The amount of plasma protein adsorbed on a phospholipid polymer having a 2-methacryloyloxyethyl phosphorylcholine (MPC) moiety was reduced compared to the amount of protein adsorbed onto poly[2-hydroxyethyl methacrylate (HEMA)], poly[n-butyl methacrylate (BMA)], and BMA copolymers with acrylamide (AAm) or N-vinyl pyrrolidone (VPy) moieties having a hydrophilic fraction. To clarify the reason for the reduced protein adsorption on the MPC polymer, the water structure in the hydrated polymer was examined with attention to the free water fraction. Hydration of the polymers occurred when they were immersed in water. The differential scanning calorimetric analysis of these hydrated polymers revealed that the free water fractions in the poly(MPC-co-BMA) and poly(MPC-co-n-dodecyl methacrylate) with a 0.30 MPC mole fraction were above 0.70. On the other hand, the free water fractions in the poly(HEMA), poly(AAm-co-BMA), and poly(VPy-co-BMA) were below 0.42. The conformational change in proteins adsorbed on the MPC polymers and poly(HEMA) were determined using ultraviolet and circular dichroism spectroscopic measurements. Proteins adsorbed on poly(HEMA) changed considerably, but those adsorbed on poly(MPC-co-BMA) with a 0.30 MPC mole fraction differed little from the native state. We concluded from these results that fewer proteins are adsorbed and their original conformation is not changed on polymer surfaces that possess a high free water fraction.

Effect of Apafant on bronchial hyperresponsiveness and down-regulation of beta-adrenoceptors induced by endotoxin in guinea pigs

Intraperitoneal injection of endotoxin resulted in bronchial hyperreactivity to histamine in guinea pigs. In addition, endotoxin (lipopolysaccharide, LPS) caused a decrease in the relaxation of the lung parenchymal strips induced by the beta-adrenoceptor agonist, isoproterenol (isoprenaline), and a reduction in the number of beta-adrenergic binding sites in the lung membrane preparation in guinea pigs. Apafant (CAS 105219-56-5, WEB 2086) was effective in the prevention of endotoxin-induced changes, i.e., bronchial hyperreactivity to histamine, a decrease in the relaxation of lung parenchymal strips induced by isoproterenol and a reduction in the number of beta-adrenergic binding sites in the lung membrane preparation in guinea pigs. Ketotifen and ozagrel also prevented the bronchial hyperresponsiveness and endotoxin-induced deterioration of the beta-adrenergic system. No remarkable effect was observed with cromolyn sodium and salbutamol in the bronchial hyperreactivity to histamine induced by endotoxin in guinea pigs. Cromolyn sodium also caused no influence on the down-regulation of beta-adrenoceptors.

[Focal cortical dysplasia and epilepsy surgery]

We conducted corticectomy in twenty-five patients with intractable partial epilepsy due to focal cortical dysplasia (FCD). MRI could not detect FCDs in three patients, interictal SPECT, however, revealed hypoperfusion corresponding to FCDs in two of these patients, while the FCD in one remaining patient was histologically identified in a resected specimen. The location of FCDs was as follows: the frontal lobe in sixteen patients, the temporal in five, the occipital in two, fronto-parietal in one, and the temporo-parietal in one. Prior to the surgery, twenty-one patients underwent invasive long-term intracranial EEG/CCTV monitoring. Of the fourteen patients who were tracked for longer than 2 years following surgery, eleven belonged to Class I according to Engel's criteria, two to Class II, and one to Class III. We compared intracranial EEG findings (interictal and ictal) between these twenty-one patients and eight patients with frontal lobe epilepsy resulting from different lesions. The results of this comparison, together with the seizure outcome following surgery, indicated that FCD is intrinsically epileptogenic. The invasive long-term monitoring should, as a rule, be performed in all patients with FCDs prior to the corticectomy.

Recommendation of early surgery from the viewpoint of daily quality of life

We surveyed pre- and postoperative levels of satisfaction with a range of the daily quality-of-life (QOL) domains in 132 sets of epilepsy surgery patients and their families. All patients underwent resective surgery for temporal lobe epilepsy and were monitored for > 2 years. Patient and family assessments showed patients' overall QOL markedly improves after surgery, depending on freedom from seizures. However, factors such as social contacts, family relations, or financial status improved little. Some families and patients were not satisfied with the postsurgical status, despite freedom from seizures. Patients who had surgery at a later age were not so satisfied with their postsurgical status as were patients who had surgery at a younger age, particularly on the QOL domains of role activities, memory function, leisure activities, or emotional well-being. This lower satisfaction level in older patients likely results from a variety of problems affecting patients during the long-lasting epileptic process; social handicaps, psychologic conflicts, and deterioration of cognitive/behavioral functions. Based on each case, we recommend that investigations start at an early stage of the illness, so that surgical intervention may be considered as early as possible.

Mechanism of Bradykinin-induced histamine release from rat peritoneal mast cells

Bradykinin at concentrations higher than 2 microM caused a significant histamine release from rat peritoneal mast cells when extracellular Ca2+ was removed from the medium. Under the same experimental conditions, bradykinin increased Ca2+ release from the intracellular Ca store of the rat peritoneal mast cells, and a clear relationship was observed between the magnitude of histamine release and an increase in fluorescence intensity. Addition of Ca2+ to the medium resulted in an inhibition of the response to bradykinin in a concentration-dependent manner. Almost the same results were obtained when Mg2+, Ba2+ and La3+ were added to the medium. Neither B1 nor B2 antagonists caused significant antagonistic effects on histamine release induced by bradykinin. However, B2 antagonists caused a histamine release of the same potency as bradykinin when applied alone. These results indicate that bradykinin-induced histamine release is not attributable to a bradykinin receptor.

[Beneficial effects of the combination of idebenone and manidipine 2HCl on neurological deficits and histological changes following cerebrovascular lesions in stroke-prone spontaneously hypertensive rats]

We investigated the effects of the combination of idebenone, an energy metabolism enhancer, and manidipine 2HCl, a dihydropyridine-derivative calcium antagonist, on neurological deficits and histological changes in the brain and kidneys of stroke-prone spontaneously hypertensive rats (SHRSP) with cerebrovascular lesions (stroke). The SHRSP were kept on a 1% NaCl solution as their drinking water to synchronize the onset of stroke. After the onset of stroke symptoms, the salt solution was replaced with tap water. On the day following the onset of stroke, idebenone (50 mg/kg), manidipine 2HCl (2 mg/kg) or a combination of idebenone (50 mg/kg) and manidipine 2HCl (2 mg/kg) was administered orally once a day for 3 weeks. In the combination group and manidipine 2HCl-treated group, the neurological deficits after the onset of stroke were ameliorated during the entire experimentalperiod. Especially, the combination significantly decreased the number of days with severe neurological deficits as compared to the control group. The combination and manidipine 2HCl significantly recovered the decrease in body weight and ameliorated the increase of brain weight, which was mainly caused by edema, significantly as compared to the control group. Manidipine 2HCl ameliorated the histological changes in the brain. In the combination group, the histological changes in both the brain and the kidneys were ameliorated. In conclusion, the combination of idebenone and manidipine 2HCl significantly ameliorated the neurological deficits and the histological changes in the brain and the kidney of SHRSP with stroke as compared to each individual treatment. We concluded that manidipine 2HCl enhances the therapeutic effect of idebenone in the treatment of cerebrovascular diseases.

Holmium: yttrium-aluminum-garnet laser for endoscopic lithotripsy

OBJECTIVES

To evaluate the holmium:yttrium-aluminum-garnet (Ho:YAG) laser for endoscopic lithotripsy on patients diagnosed with urinary tract calculi.

METHODS

Thirty-eight procedures utilizing transurethral ureterolithotripsy or percutaneous nephroureteral lithotripsy were evaluated: 5 renal calculi, 31 ureteral calculi (most in the upper ureter), 1 ureteropelvic junction calculus, and 1 bladder calculus. These were mainly in cases that, after being treated with extracorporeal shock-wave lithotripsy (ESWL), were contraindicated for further ESWL. Laser parameters included energy of 0.5 to 1.0 J/pulse and pulse rate of 5 to 10 Hz.

RESULTS

Composition of calculi was determined in 26 procedures. The Ho:YAG laser was effective for fragmenting all types of calculi. Patient outcome evaluated at 6 weeks after treatment showed that 33 of 38 procedures (87%) were effective. Residual calculi in 4 of the 5 unsuccessful procedures were less than 5 mm in size and judged to be able to pass spontaneously. In the remaining procedure, the calculus was passed spontaneously 3 months after treatment. No severe damage to tissues or adverse effects to the body were observed due to the Ho:YAG laser.

CONCLUSIONS

On the basis of these results, we determine that this wavelength is effective for lithotripsy in addition to its previously reported usefulness for soft tissue applications, and, thus, is a cost-effective and highly useful clinical device.

Distribution of genes encoding cholera toxin, zonula occludens toxin, accessory cholera toxin, and El Tor hemolysin in Vibrio cholerae of diverse origins

A large collection of 1154 strains of Vibrio cholerae of diverse origins including serogroups 01 and 0139 and those belonging to the non-01 and non-0139 (non-01:non-0139) serogroups were examined with a battery of DNA probes specific for cholera toxin (CT), zonula occludens toxin (ZOT), accessory cholera toxin (ACE) and El Tor hemolysin (HLY) to determine the distribution of genes among wild strains and to understand the importance of these factors in the pathogenesis of the disease cholera. Among the 01 clinical isolates, the majority of the strains had an intact core region (ctx, zot, ace) and also possessed the hlyA gene. Although rare, strains of 01 with natural deletions of the ctx, zot and/or ace genes were also detected. The absence of the virulence genes comprising the core region and the presence of the hlyA gene dominated the 01 environment, food isolates and the clinical and environmental non-01: non-0139 strains of V. cholerae. All the 0139 strains examined in this study possessed genes located in the core region and the hlyA gene. Among all the virulence-associated genes examined, the hlyA gene was the most conserved genetic element in V. cholerae independent of biotypes and serogroups.