Characteristics of monocarboxylates as energy substrates other than glucose in rat brain slices and the effect of selective glial poisoning - a 31P NMR study

In rat brain slices we examined the differences in the levels of high-energy phosphates in the presence of various energy substrates by using 31P NMR with a time resolution of 4 min at 25 degrees C. In parallel experiments we recorded population excitatory postsynaptic potentials (EPSPs) from granule cells in rat hippocampal slices. During high K(+) stimulation (8 min) phosphocreatine (PCr) decreased to a low level and recovered to the control level in standard artificial cerebrospinal fluid (ACSF) in about 10 min. Population EPSPs disappeared following high-K(+) stimulation and recovered in standard ACSF. In iodoacetic acid (IAA)-pretreated slices, whereas glucose was unable to support energy metabolism, the PCr level, which decreased following high-K(+) stimulation, recovered in ACSF containing lactate or pyruvate. The half-time of recovery of PCr levels in ACSF containing lactate was longer than that containing glucose. Population EPSPs in standard ACSF were maintained for more than 1 h, but those in ACSF containing lactate decreased gradually by about half in 40 min. In IAA-pretreated slices, when further treated with fluorocitrate (100 microM) for 2 h, the recovery of the PCr level in ACSF containing lactate after high-K(+) stimulation was completely abolished, whereas the recovery of the PCr level in ACSF containing pyruvate was unaffected. These results indicate that neurons can utilize pyruvate as well as glucose, but not lactate, as exogenous energy substrates, and that lactate may be metabolized to pyruvate in glial cells and transported to neurons to be utilized as an energy substrate.

A linkage map of 243 DNA markers in an intercross of Göttingen miniature and Meishan pigs

A resource family of pigs has been constructed by using a boar of Göttingen miniature pig and two sows of Meishan pig as parents. In the construction of the family, two F1 males and 18 F1 females were intercrossed to generate 143 F2 offspring. The members of the family were genotyped using 243 genetic markers including 26 markers developed in our laboratory in order to generate a linkage map of markers for use in detecting quantitative trait loci (QTLs) in the family. The markers consisted of 237 microsatellites, five PRE-1 markers, and one RFLP marker. The linkage map was revealed to cover all 18 autosomes and the X chromosome; and the total length of the sex-averaged linkage map was calculated to be 2561.9 CM. Four out of the 26 markers developed in our laboratory exended the current linkage map at the termini of chromosomes 1p, 5p, 11p, and Xq. The linkage maps of all the chromosomes except for chromosome 1 were found to be longer in females than in males. Concerning chromosome 1, the length of the linkage map showed no difference between females and males, which was attributed to low recombination rates between markers localized in the centromeric region in females. The average ratio of female-to-male recombination was calculated to be 1.55.

Fibroxanthoma arising from the cranial dura mater

A primary xanthomatous tumor is very rare in the central nervous system (CNS). Here we report the case of a fibroxanthoma arising from the dura mater of the cerebrum that demonstrated no systemic disease or metabolic abnormalities. A 19-month-old, otherwise healthy boy was found to have an enlarged head. Magnetic resonance imaging demonstrated a left occipital dural mass lesion and an enlarged left cerebral hemisphere with ipsilateral ventricular enlargement. Subtotal removal of the tumor was performed through the left parieto-occipital craniotomy. The tumor was composed of a central fibrous portion, a peripheral xanthomatous area, and a boundary. The peripheral area of the tumor showed abundant uniform xanthomatous cells with a thin fibrous stroma and the mass was diagnosed as fibroxanthoma involving the dura. This may represent a distinct category of tumor, which is different from the previously reported cases of fibrous xanthoma and fibrous histiocytoma. Intracranial xanthomatous tumors may be heterogeneous in their origin and histological features. However, further studies are needed to elucidate their clinical features, biological behavior, and optimal treatment strategies.

Treatment of infantile spasms with zonisamide

We determined the efficacy of and tolerability to zonisamide (ZNS) in newly diagnosed patients with infantile spasms. ZNS, 4-20 mg/kg per day, was introduced as an add-on therapy or monotherapy in 27 children with infantile spasms (cryptogenic, 2; symptomatic, 25). The dosage was initially 2-4 mg/kg per day, and then was increased by 2-5 mg/kg every 2-4 days until the seizures disappeared. Nine (33.3%) out of the 27 patients who were administered ZNS exhibited the disappearance of seizures. ZNS was effective in all the cryptogenic cases and seven (28.0%) of the symptomatic cases. The effective daily doses were 5-12.5 mg/kg (mean, 7.8 mg/kg), and the daily dosages were 40-100 mg (mean, 61.1 mg). The steady-state plasma ZNS concentrations were almost within the therapeutic range. The mean time interval between the start of ZNS therapy and the seizure disappearance was 5.0 days. Six (75.0%) of eight effective cases, the exception being one for whom EEG was not performed after the therapy, showed the disappearance of hypsarrhythmia. The recurrence of seizures were observed in four of the nine cases. No adverse reaction to ZNS was noted in any patient. In conclusion, ZNS treatment is considered to be worthwhile trying, for early stage therapy for infantile spasms.

Cerebellar control of the cardiovascular responses during postural changes in conscious rabbits

In conscious control rabbits, tilting the head 30 degrees up from a position 30 degrees down induced initially an inhibition in the renal sympathetic nerve activity (RSNA), however this inhibition immediately released and became a transient increase. Following these responses in RSNA, blood pressure (BP) initially decreased but recovered to the control level within 3-5 s. After bilateral destruction of the lateral nodulus-uvula in the cerebellum, in contrast, the same tilting of the head caused an immediate large increase in RSNA without early inhibition, which was sustained at a high level. BP increased transiently, but then decreased and remained at a level lower than the control. These results indicate that the timing and duration of this transient increase in RSNA during tilting the head up are controlled by the lateral nodulus-uvula and may be important in the rapid adaptation of blood pressure. In addition, this suggests that the lateral nodulus-uvula may play an important role in the cardiovascular control under conditions of consciousness during changes in head position and body posture.

[Efficacy of continuous intravenous infusion of midazolam in the treatment of status epilepticus in children]

Midazolam infusion was tried as the treatment for 48 episodes of refractory status epilepticus or a cluster of seizures in 16 children. The mean age of patients was 3.5 years (range, 1 month to 18 years). Nine children had epilepsy, one purulent meningitis, one encephalitis, one acute cerebral infarction, and the remaining four had acute phase of hypoxic ischemic encephalopathy. The type of the seizure was a generalized tonic clonic seizure (including a partial seizure secondarily generalized) in 41 episodes, a tonic seizure in 3, an atypical absence in 1, and a complex partial seizure in 3, respectively. All patients received intravenous midazolam at 0.15 mg/kg as bolus, followed by a continuous infusion at 0.1-0.15 mg/kg/hr initially. The dose was increased gradually up to 0.3 mg/kg/hr until the complete control of seizures was achieved. Fourty-one of the 48 episodes of seizures were controlled within 30 minutes after the initiation of midazolam therapy. The mean infusion rate of midazolam required was 0.22 mg/kg/hr. The mean duration of the treatment was 4.1 days. None of the patients had serious changes in the blood pressure or respiratory status attributable to the use of midazolam. In conclusion, midazolam infusion is an effective and safe therapeutic approach for the management of childhood status epilepticus.

[A case of thoracic extradural spinal cord teratoma with neurological sequelae more than 10 years after surgery]

We describe a rare case of a 42-year-old man with extradural spinal cord teratoma who presented with left Brown-Séquard syndrome more than 10 years after surgery for a left posterior mediastinal tumor. When he was 29 years old, he underwent an operation for a posterior mediastinal tumor. Histological findings showed adenocarcinoma in teratoma. Ten years after the operation, the patient developed left leg weakness. Three years later, he developed superficial sensory disturbance in his right leg. MRI showed extradural tumor formation at the level of the Th 9 vertebra, which compressed the spinal cord from the left posterior side. At surgery, the tumor was well encapsulated and extended to the left posterior side of the spinal cord through the intervertebral foramen. The histological findings were almost identical to those from the mediastinal tumor. This dumbbell tumor apparently developed from the remainder of the posterior mediastinal tumor over a period of more than 10 years.

Oral-facial-digital syndrome type IX in a patient with Dandy-Walker malformation

We report a girl with oral, facial, and digital anomalies including multiple alveolar frenula, lobulated tongue with nodules, a posterior cleft palate, hypertelorism, a prominent forehead with a large anterior fontanelle, and postaxial polydactyly in both hands and the right foot, features compatible with the oral-facial-digital syndrome (OFDS). In addition, she had bilateral microphthalmia, optic disc coloboma, and retinal degeneration with partial detachment, thus establishing a diagnosis of OFDS type IX. Dandy-Walker malformation and retrobulbar cysts were observed on MRI. These additional malformations have not been reported in OFDS type IX. The frequent apnoeic spells which occurred immediately after birth were relieved after cystoperitoneal shunt implantation for hydrocephalus. Considering our case and previous reports of OFDS type IX, including two male sibs, a boy born to consanguineous parents, and three females, inheritance is probably autosomal recessive.

Development of a testicular haemangioma after interferon therapy for hepatic haemangiomas: a case report

We report a 2-month-old Japanese boy presenting with large multiple haemangiomas invading his liver. He was treated with daily subcutaneous injection of interferon alfa (IFN-alpha)-2a with progressive reduction of the hepatic haemangioma. He developed a scrotal mass 2 months after discontinuation of IFN, and this mass eventually required surgical management. Resected tumour was a juvenile haemangioma. The escape of this haemangioma from IFN therapy may be correlated to the quite low level of injected IFN in testis.

CONCLUSION

IFN therapy may not be curative for testicular haemangioma although it is effective in shrinking haemangiomas of the liver and skin.

Can twin fetuses be numerically clustered characterizing fetal cardiovascular system function?

To clarify whether twin fetuses could be clustered quantitatively observing in utero cardiovascular system function, 71 twin-paired fetuses between 24 and 40 weeks' gestation were subjected. Cluster analysis was performed using four variables; end-diastolic dimension and fractional shortening in the right ventricle (EDD, FS), resistance index in the umbilical artery (RIUA) and urine production rate (UPR). Three different groups were revealed. In Cluster 1 (C1), larger fetuses showed a significant increase in both EDD and UPR, and a significant decrease in FS, while smaller fetuses had a significant increase in RIUA and a decrease in UPR. In Cluster 2 (C2), smaller fetuses showed a significant increase in RIUA. Cluster 3 (C3) showed no significant deviations in any variable when referring to singleton pregnancies. C1 had a higher perinatal mortality rate than either C2 or C3, with the cause of death being cardiac failure in larger fetuses and renal failure in smaller fetuses. The frequencies of discordancy, hemoglobin difference above 5 g/dl and monochorionic placenta in C1 were also higher than fetuses in C3. C2 also showed higher frequencies of discordancy and small-for-gestational age than C3 fetuses. In C2 and C3, respiratory insufficiency was found to be the cause of neonatal death. The results revealed that C1 consists of twins with both larger and smaller fetuses displaying cardiac failure with an increase in renal perfusion and a decrease in renal and placental perfusion, respectively, and C2 consists of twins with smaller fetuses having both placental insufficiency and intrauterine growth retardation. C3 consists of twins with both lager and smaller fetuses having normal circulation, when compared to singleton pregnancy.

Simultaneous measurements of lactate and blood flow during hypoxia and recovery from hypoxia in a localized region in the brain of the anesthetized rabbit

We observed simultaneous changes in lactate level and regional blood flow (rBF) in the brain of the anesthetized rabbit by using localized proton magnetic resonance spectroscopy (1H MRS) and laser Doppler flowmetry. The volume of interest of 0.5 ml for 1H MRS contained mostly thalamic nuclei. During hypoxia peak area for lactate increased up to 57% of that from N-Acetylaspartate. While the rBF increased during hypoxia up to 260% of the control, oxygen delivery (rBF x arterial oxygen content) decreased. In the normoxic recovery period following hypoxia, the rBF recovered slowly and a consequent overshoot of oxygen delivery was observed. The multiple and stepwise linear regression analyses revealed that the averaged decrease in oxygen delivery during hypoxia was the most significant independent variable for the increase in lactate during hypoxia (correlation coefficient; r2 = 0.68) and also that the increase in lactate during hypoxia was the most significant independent variable for the time for half-recovery of rBF (r2 = 0.75). These results suggest that the increase in lactate during hypoxia is due to the deficiency of oxygen delivery and that the increase in lactate during hypoxia prolongs the period of enhancement of rBF during recovery from hypoxia.

Magneto-encephalographical analysis of focal cortical heterotopia

Focal cortical heterotopia is often associated with intractable seizures. Recent papers have reported that magnetic resonance imaging (MRI) demonstrates cortical heterotopia well compared with other imaging modalities, e.g. computed tomography scan. The authors analyzed the localization of epileptic spike foci of focal cortical heterotopia by 37 channel magnetoencephalography (MEG), and superimposed these dipoles on MRI. The estimated dipoles were observed to be located in a limited area, which corresponded to a focal cortical heterotopia on MRI. The present paper demonstrates that the combination of MEG and MRI is very advantageous for determination of the three dimensional localization of epileptic foci in patients with focal cortical heterotopia.

RpoS-dependent regulation of genes expressed at late stationary phase in Escherichia coli

We have identified 6 Escherichia coli genomic genes, including 4 new genes, responsive to the stationary phase. One of them was regulated positively by RpoS at the stationary phase, and the remaining 5 negatively at a late stationary phase, all of them responding to multiple environmental stresses. Nucleotide sequences as well as such multiple responses revealed that those genes may have more than one overlapping-promoter recognized by different sigma-factors which regulate gene expressions during their cell growth.

[A case of Kennedy-Alter-Sung (KAS) syndrome presenting as hypersexuality and elevated serum CK: usefulness of genetic analysis]

We report a unique case of KAS syndrome presenting as hypersexuality and elevated serum creatine kinase (CK). None of the other members of the patient's family had KAS. The patient had engaged in sexual behavior 4 approximately 5 times a week since his marriage. He did not have gynecomastia or hepatomegaly. Neurological examination revealed facial twitching and tongue atrophy and fasciculations. Mild to moderate muscular atrophy and weakness were evident in the proximal portion of the upper and the distal portion of the lower extremities. Deep tendon reflexes were absent, as were sensory disturbance and sphincter dysfunction. Laboratory data showed mild elevation of transaminase (GOT 113 U/L, GPT 69 U/L) and extreme elevation of CK (4,600 U/L) in serum. Electromyography and muscle biopsy from the left biceps showed chronic neurogenic atrophy. Genetic analysis showed increased expansion of a CAG repeat (44 repeats) in exon 1 of the androgen receptor gene. We diagnosed KAS syndrome based on the genetic analysis. This case is important in illustrating the clinical varieties of KAS syndrome, as well as the importance of genetic analysis in KAS syndrome cases presenting with atypical manifestations and without a family history.

Magnetoencephalographic analysis of rolandic discharges in benign childhood epilepsy

We report the detailed analysis of the generator and propagation of rolandic discharges in benign childhood epilepsy with centrotemporal spikes by means of 37-channel magnetoencephalography with neuromagnetic three-dimensional dipole localization. Equivalent current dipoles of prominent negative sharp waves of rolandic discharges appeared as tangential dipoles in the rolandic region, positive poles being situated anteriorly. These equivalent current dipoles showed a relatively limited localization and regular directions compared with other components. Equivalent current dipoles of preceding small positive waves, positive waves following negative sharp waves, and negative slow waves appeared in the vicinity of negative sharp waves. Equivalent current dipoles of rolandic discharges were located around the generator of somatosensory evoked magnetic fields stimulated at the lower lip. These findings suggest that rolandic discharges are generated through basically a mechanism similar to that for the middle-latency components of somatosensory evoked responses.

Patent ductus venosus associated with a hyperintense globus pallidum on T1-weighted magnetic resonance imaging and pulmonary hypertension

We report the case of a 13-year-old Japanese boy with a patent ductus venosus. He experienced mild disorientation and hallucination at age 8 years. Hyperammonaemia was discovered at age 12 years. Brain MRI demonstrated multiple intracranial hyperintense lesions, mainly in the globus pallidum, which suggested portosystemic encephalopathy. Patent ductus venosus was demonstrated by abdominal ultrasonography and angiography. Cardiopulmonary investigation revealed pulmonary hypertension. An intracranial hyperintense lesion observed on T1-weighted MRI may be an initial clue for discovering a patent ductus venosus in asymptomatic patients.

CONCLUSION

When patent ductus venosus is disclosed, pulmonary hypertension should be sought, as in cases with other portosystemic shunts.

Beneficial effect of growth hormone on atherogenic risk in children with growth hormone deficiency

We studied changes in the atherogenic index (total cholesterol divided by high-density lipoprotein cholesterol) in 12 prepubertal boys with growth hormone (GH) deficiency during 9 months of GH treatment. High-density lipoprotein cholesterol level increased until 5 months without significant changes in total cholesterol level; thus GH therapy may be beneficial in reducing the atherogenic index in boys with GH deficiency.

Antitumor effect of arterial administration of a medium-chain triglyceride solution of an angiogenesis inhibitor, TNP-470, in rabbits bearing VX-2 carcinoma

Using rabbits bearing VX-2 carcinoma on the inner side of the leg, we examined the antitumor activity of a medium-chain triglyceride (MCT) solution of an angiogenesis inhibitor, TNP-470 (AGM-1470, 6-O-(N-chloroacetylcarbamoyl)-fumagillol), following administration into the femoral artery feeding the tumor. The MCT solution of TNP-470 (1 and 5 mg) strongly suppressed tumor growth following a single intra-arterial (i.a.) injection 2 or 3 weeks after tumor inoculation. Moreover, remarkable regression of well-developed tumors, those 4 weeks after inoculation, was obtained by i.a. injection of the MCT solution containing 20 mg of TNP-470 without any influence on body weight. The antitumor effects were potentiated by coadministration of doxorubicin or mitomycin C (MMC) in the solution or microspheres containing MMC. In a shell-less chorioallantoic membrane (CAM) assay, angiogenesis was inhibited when a droplet of the MCT solution containing 25 micrograms of TNP-470 was placed on the CAM for 2 days, suggesting that the prolonged antitumor effect resulted from the inhibition of tumor neovascularization by sustained drug release from the preparation. These results indicate that i.a. injection of the MCT solution of TNP-470 is promising for treating well-developed tumors.