Electron spin resonance of particulate soot samples from automobiles to help environmental studies.

The application of electron spin resonance (ESR) was studied for diesel soot samples and suspended particulate matter (SPM) from automobile engines. Soot samples or diesel exhaust particles (DEP) were recovered at various points: in the exhaust pipe of a diesel engine, at the dust sampler of a highway tunnel (standard DEP), on the soundproofing wall alongside a heavy traffic road, and on the filters of a dust sampler for SPM. The diesel soot samples apparently showed two ESR spectra: one was a broad spectrum at g=2.1 with a line width of ca. 80-120 mT and the other was a sharp signal of a carbon radical at g=2.003 with a line width of 0.4 mT. Annealing experiments with a DEP sample at 250 degrees C revealed drastic enhancement of the sharp ESR signal, which suggested a thermal process of carbonization of remnant organics. An oximetric study by ESR showed an enhancement of the broad signal in the diesel soot sample as well as in the sharp ESR signal. Therefore, the main part of the broad ESR signal would be attributed to carbon radicals, which form a different configuration, probably closely interacting aggregates. Enhancement of the sharp ESR signal was not observed in the standard DEP sample under vacuum condition, which suggested less adsorption sites on the surface of DEP samples.

Early prepubertal ontogeny of pulsatile gonadotropin-releasing hormone (GnRH) secretion: I. Inhibitory autofeedback control through prolyl endopeptidase degradation of GnRH.

GnRH[1-5], a subproduct resulting from degradation of GnRH by prolyl endopeptidase (PEP) and endopeptidase 24.15 (EP24.15) was known to account for an inhibitory autofeedback of GnRH secretion through an effect at the N-methyl-D-aspartate (NMDA) receptors. This study aimed at determining the possible role of such a mechanism in the early developmental changes in frequency of pulsatile GnRH secretion. Using retrochiasmatic explants from fetal male rats (day 20-21 of gestation), no GnRH pulses could be observed in vitro, whereas pulses occurred at a mean interval of 86 min from the day of birth onwards. This interval decreased steadily until day 25 (39 min), during the period preceding the onset of puberty. Based on GnRH[1-10] or GnRH[1-9] degradation and GnRH[1-5] generation after incubation with hypothalamic extracts, EP24.15 activity did not change with age, whereas PEP activity was maximal at days 5-10 and decreased subsequently until day 50. These changes were consistent with the ontogenetic variations in PEP messenger RNAs (mRNAs) quantitated using RT-PCR. Using fetal explants, the NMDA-evoked release of GnRH was potentiated in a dose-dependent manner by bacitracin, a competitive PEP inhibitor and the desensitization to the NMDA effect was prevented using 2 mM of bacitracin. At day 5, a higher bacitracin concentration of 20 mM was required for a similar effect. Pulsatile GnRH secretion from fetal explants was not caused to occur using bacitracin or Fmoc-Prolyl-Pyrrolidine-2-nitrile (Fmoc-Pro-PyrrCN), a noncompetitive PEP inhibitor. At postnatal days 5 and 15, a significant acceleration of pulsatility was obtained using 1 microM of Fmoc-Pro-PyrrCN or 2 mM of bacitracin. At 25 and 50 days, a lower bacitracin concentration of 20 microM was effective as well in increasing the frequency of GnRH pulsatility. We conclude that the GnRH inhibitory autofeedback resulting from degradation of the peptide is operational in the fetal hypothalamus but does not explain the absence of pulsatile GnRH secretion at that early age. After birth, PEP activity is high and may account for the low frequency of pulsatility. The potency of that effect decreases before the onset of puberty and may contribute to the acceleration of GnRH pulsatility.

Hypothalamic-pituitary function in growth hormone-deficient patients with pituitary stalk transection.

We compared 1.5 T magnetic resonance (MR) image findings with hypothalamic-pituitary function in 11 patients with idiopathic pituitary dwarfism, each of whom had a history of perinatal abnormalities, and 1 patient with posttraumatic pituitary dwarfism. MR imaging revealed transection of the pituitary stalk in all patients and the formation of an ectopic posterior lobe at the proximal stump in 9 patients, none of whom had polydipsia or polyuria. Three patients without an ectopic posterior lobe had diabetes insipidus. The 5 patients who had small pituitary glands (less than 2 mm in height) had hypothyroidism with low serum TSH concentrations and low serum cortisol responses to insulin-induced hypoglycemia; however, 7 patients with normal-sized pituitary glands had normal thyroid and adrenal function. The serum GH response to GHRH did not correlate with the size of the pituitary gland. The patients with small pituitary glands had delayed or prolonged serum TSH responses to TRH and impaired serum LH and FSH responses to GnRH; 4 of the patients with normal-sized pituitary glands had normal serum TSH, LH, and FSH responses. Only 2 patients had high basal serum PRL concentrations. The endocrinological data suggest that reestablishment of the hypothalamo-hypophyseal portal circulation, which cannot be seen by MR imaging, may occur. We suggest that the primary cause of idiopathic pituitary dwarfism in many patients is injury to the pituitary stalk at birth.

Glycogen storage disease type III with muscle involvement: reappraisal of phenotypic variability and prognosis.

A review of the case histories of 19 Japanese patients with enzymatically proven glycogen storage disease (GSD) III who developed muscular symptoms at various ages illustrates the phenotypic variability of this disease. There seem to be 4 subgroups of GSD III with muscle involvement according to the clinical symptoms. The first group of patients is characterized by the childhood onset of muscle weakness and hepatic disorders. The second group of patients develops muscular symptoms in adult years while the liver symptoms start in childhood. The third group includes the patients whose muscle weakness started in adult years long after liver symptoms in childhood had disappeared. The fourth group shows only muscular symptoms as adults without any sign or history of liver dysfunction since childhood. The prognosis for each subgroup seems to be different; however, none of them appears to be better than that for GSD I, as has been suggested previously.

Protein-losing gastroenteropathy with facial anomaly and growth retardation: a mild case of Hennekam syndrome.

A 7-year-old boy with a peculiar face, protein-losing gastroenteropathy and growth retardation is reported. Although he has a face similar to those 5 cases reported previously by Hennekam et al. (Am J Med Genet 34:593-600, 1989) and Gabrielli et al. (Am J Med Genet 40:244-247, 1991), he is not mentally retarded nor does he have severe lymphedema. This patient seems to have a mild case of the Hennekam syndrome.

Relatively longer hand in patients with Ullrich-Turner syndrome.

We analyzed the total hand length (HL) and length of noncarpal bones (NCL) in 50 Japanese patients with Ullrich-Turner syndrome (UTS) and in 443 other patients with short stature used as controls. In each patient group we calculated relative HL (RHL= HL/height) and relative NCL (RNCL= NCL/height). UTS patients had significantly greater RHL than controls. The greater RHL in UTS patients is mainly due to their longer, short tubular bones. The RHL is not affected by ages and karyotypes of UTS patients or growth hormone treatments given to them. We conclude that relatively longer hands are a common manifestation of UTS and that this parameter is useful for the diagnosis of the syndrome among short females, who usually need chromosome analysis.

Changes in cerebral blood flow after carotid endarterectomy.

We evaluated changes in cerebral blood flow (CBF) after carotid endarterectomy (CEA) in patients with internal carotid (ICA) stenosis. We studied 46 patients with ICA stenosis who underwent CEA. The mean age of the patients was 63 years, and their mean ICA stenosis was 73%. CBF in the middle cerebral artery territory was measured with xenon-enhanced CT tomography (Xe-CT) before and 3 weeks after CEA. In addition, cerebrovascular reactivity (CVR) was measured after intravenous administration of acetazolamide (ACZ) in 16 patients. There was no significant relationship between the degree of stenosis and CBF. Ten patients had decreased CBF before CEA, and CBF improved in nine of these after CEA. The CVR in 6 of 7 patients with impaired CVR before CEA improved to varying degrees after CEA. The CBF in patients with ICA stenosis varied according to the degree of collateral circulation. In conclusion, CEA can increase CBF and improve CVR in patients with low CBF or low CVR by restoring blood flow through the ICA.

Duality of glutamatergic and GABAergic control of pulsatile GnRH secretion by rat hypothalamic explants: I. Effects of antisense oligodeoxynucleotides using explants including or excluding the preoptic area.

Using antisense oligodeoxynucleotides we aimed to study the role of N-methyl-D-aspartate (NMDA) and gamma-aminobutyric acid (GABA) receptors in the mechanism of Gonadotrophin-releasing hormone (GnRH) secretion in vitro. Since GnRH cell bodies are located in the rat preoptic hypothalamus while most GnRH terminals are in the retrochiasmatic hypothalamus, we compared the effects of oligodeoxynucleotides on explants of the whole (preoptic area included) or retrochiasmatic hypothalamus. When GnRH secretion is evoked by muscimol and NMDA, a time-related reduction of GnRH secretion is caused by antisense oligodeoxynucleotides for the beta subunit of the GABAA receptor and the NR2A subunit of the NMDA receptor, respectively. After 6-7 h, binding studies of tritiated ligands show a decrease in GABA- and NMDA-receptor expression. While these antisense effects are observed using whole explants, no such effects are seen using retrochiasmatic explants, indicating that the facilitatory GABAA and NMDA receptors are encoded in the preoptic area. Using several missense oligodeoxynucleotides or antisense for the NR2B and NR2C subunits of the NMDA receptor, the muscimol- and NMDA-evoked release of GnRH is not affected. When spontaneous pulsatile GnRH secretion is studied, the NR2A antisense oligodeoxynucleotides cause an increase of the interpulse interval. This increase is seen using whole but not retrochiasmatic explants. In contrast, the GABAA and NR2C antisense oligodeoxynucleotides result in a reduction of GnRH interpulse interval. Such a reduction is seen using whole as well as retrochiasmatic explants, indicating that the GABAA and NMDA receptors which mediate inhibition of GnRH pulsatility are encoded in the retrochiasmatic hypothalamus. We conclude that NMDA receptors (NR2A subunit) encoded in the preoptic hypothalamus mediate a facilitatory effect on GnRH pulsatility while GABAA and NMDA (NR2C subunit) receptors encoded in the retrochiasmatic hypothalamus mediate an inhibition of GnRH pulsatility. Pulsatile GnRH secretion is affected differently than the agonist-evoked release of GnRH suggesting that the GnRH secretory neurons and the GnRH pulse generator consist of different cellular entities.

Duality of glutamatergic and GABAergic control of pulsatile GnRH secretion by rat hypothalamic explants: II. Reduced NR2C- and GABAA-receptor-mediated inhibition at initiation of sexual maturation.

N-methyl-D-aspartate (NMDA) receptors and gamma-aminobutyric acid (GABA) receptors are involved in the mechanism of pulsatile gonadotrophin-releasing hormone (GnRH) secretion. The aim of this study was to elucidate the role of those receptors in the acceleration of pulsatile GnRH secretion seen at onset of puberty. Using hypothalamic explants from prepubertal (15 days), early pubertal (25 days) and adult (50 days) male rats, we studied the effects of pharmacological antagonists and antisense oligodeoxynucleotides on GnRH release evoked by NMDA and GABA receptor agonists as well as the interval between spontaneous GnRH secretory pulses. At the three studied ages, the muscimol-evoked release of GnRh is similarly inhibited by the GABAA receptor antagonist bicuculline. In contrast, the frequency of pulsatility is stimulated by bicuculline as indicated by a reduction of the mean GnRh interpulse interval from 60 to 40 min and such an effect is seen at 15 days only. The GnRH interpulse interval is also reduced by GABAA receptor antisense oligodeoxynucleotides at 15 days while no effects are seen at 25 days. At the three studied ages, the NMDA-evoked release of GnRH and the GnRh interpulse interval are similarly inhibited by 100 or 500 microM of the NMDA receptor antagonist 7-chlorokynurenic acid (7CK). These effects are consistent with the increase of GnRH interpulse interval caused by NR2A antisense oligodeoxynucleotides at 15 days (86 vs 64 min in controls) as well as 25 days (44 vs 36 min). A low (5 microM) concentration of 7CK does not result in any effect except a reduction of GnRH interpulse interval which is seen at 15 days only. A similar reduction of GnRh interpulse interval is obtained using NR2C antisense oligodeoxynucleotides at 15 days (50 vs 64 min in controls) while no effects are seen at 25 days (35 vs 36 min). At 25 days, muscimol can prevent the developmental increase in frequency of pulsatile GnRH secretion. In summary, pulsatile GnRH secretion by the prepubertal hypothalamus characteristically involves an inhibition mediated through GABAA receptors and the NR2C subunit of NMDA receptors. Based on these data, we propose a model for the mechanism of the onset of puberty which involves the disappearance or inactivation of GABAergic neurons located in the retrochiasmatic hypothalamus and expressing the NR2C subtype of NMDA receptors.

Type 3 GM1 gangliosidosis: clinical and neuroradiological findings in an 11-year-old girl.

An 11-year-old Japanese girl was diagnosed as having type 3 GM1 gangliosidosis by clinical symptoms and enzyme assay. She was the youngest among the patients with type 3 GM1 gangliosidosis whose clinical and neuroradiological findings have been documented. Clumsiness since early infancy and dystonia since early childhood which progressed slowly without mental deterioration and dysmorphism led us to the diagnosis of type 3 GM1 gangliosidosis. Genotype determination showed point mutation in exon 2 of the beta-galactosidase gene, which is common among the patients reported in Japan. T2-weighted MRI demonstrated bilateral symmetrical hypointensity in the putamen and globus pallidus. Single photon emission computed tomography using 99mTc-HMPAO showed bilateral hyperperfusion in the basal ganglia which decreased gradually during 1 year of observation. Twenty-two patients with type 3 GM1 gangliosidosis reported in the literature whose onset was at under 15 years of age were reviewed.

Comparison of transcranial Doppler investigation of aneurysmal vasospasm with digital subtraction angiographic and clinical findings.

OBJECTIVE: Transcranial Doppler (TCD) findings for evaluation of the severity of vasospasm (VSP) in patients with ruptured aneurysmal subarachnoid hemorrhage are controversial. To clarify these TCD findings, intra-arterial digital subtraction angiography was used to simultaneously investigate the angiographic features of cerebral vessels and the cerebral circulation time (CCT). METHODS: Fifty patients with ruptured aneurysms, for whom computed tomographic scans indicated Fisher Grade III subarachnoid hemorrhage, were investigated. Aneurysmal neck clipping was performed in the acute stage. The mean flow velocity (MFV) at the M1 segment was measured using TCD ultrasonography. Intra-arterial digital subtraction angiography was used to simultaneously investigate angiographic features and CCTs on Days 7 to 13. The CCT was defined as the time difference between the two peaks in optical density curves recorded at the carotid artery (C3-C4 portion) and the ascending vein, after contrast material injection. Angiographic VSP was categorized using a modification of the Fisher classification. RESULTS: Angiograms for 9, 25, and 16 patients showed no, slight to moderate, and severe VSP, respectively. The MFVs of the patients with no, slight to moderate, and severe VSP were 70, 115, and 116 cm/s, respectively. No significant difference among the three groups could be observed. The mean CCTs of the patients with no, slight to moderate, and severe VSP were 4.1, 4.6, and 6.5 seconds, respectively. The CCTs of the patients with severe VSP differed significantly from those of the patients with no or slight to moderate VSP. The patients with severe VSP were divided into two groups. One group included eight patients with severe VSP at proximal sites (the internal carotid artery to the M1 segment), and the other included eight patients with severe VSP extending to the M2 segment and more peripheral sites. The mean CCT of the former group (5.3 s) was significantly different from that of the latter (7.5 s), and the MFV of the former group (128 cm/s) was significantly higher than that of the latter (81 cm/s). The clinical outcomes for the latter patients were more serious than those for the former patients. CONCLUSION: This study suggests that the MFV at the M1 segment is inadequate for estimation of the severity of VSP extending to vessels more peripheral than the M1 segment. Furthermore, severe VSP extending to more peripheral sites can produce more serious ischemic insults, compared with that localized to basal vessels. Patients with negative TCD results and clinical features suggesting the development of VSP should undergo quantitative investigation of cerebral circulatory parameters, such as the CCT, using intra-arterial digital subtraction angiography.

Normal mutation frequencies of somatic cells in patients receiving growth hormone therapy.

The number of reported cases of malignancy developing in growth hormone (GH) users worldwide has increased to more than 40. However, the causal relationship between GH administration and the occurrence of malignancies is still uncertain. We investigated somatic cell mutation frequencies (Mfs) or variant frequency (Vf) at three gene loci in patients with pituitary dwarfism receiving GH therapy to clarify the genetic effect of GH. Eighty-eight patients receiving GH therapy for at least 3 months and 42 age-matched healthy controls were studied. Mfs at hypoxanthineguanine phosphoribosyltransferase (HPRT) and T-cell receptor (TCR) loci in GH users were not significantly higher than in the controls. Although a few patients seemed to have a slightly increased Vf at the glycophorin A (GPA) locus, the difference was not statistically significant. In addition, there was no tendency for the Mfs (Vf) at these loci to increase with the duration of the GH therapy. These data seem to exclude the possibility that GH induces genetic instability in patients with pituitary dwarfism who are receiving GH therapy.

Developmental changes of plasma ganglioside concentration during the neonatal period.

We investigated the developmental changes of plasma ganglioside concentration during the neonatal period. The mean plasma ganglioside concentration at birth was 8.22 +/- 3.70 nmol lipid-bound sialic acid (LBSA)/ml, significantly lower than the value in adults (12.05 +/- 1.36 nmol LBSA/ml, P less than 0.02). However, it increased rapidly early in the neonatal period and reached its maximum level at 14 days of age (16.25 +/- 6.04 nmol LBSA/ml), which was higher than that of adults (P less than 0.05); then it decreased slowly to the adult level at one month of age. The mean plasma ganglioside concentration in preterm infants (gestational age less than 37 weeks) was 6.65 +/- 3.35 nmol LBSA/ml, somewhat lower than that of fullterm infants (gestational age greater than or equal to 37 weeks, 9.90 +/- 3.39 nmol LBSA/ml, P less than 0.02) at birth. After birth, it increased much more rapidly in preterm infants and there was no significant difference between these two groups at 5 days of age. Plasma ganglioside concentration at birth increased gradually in correlation with gestational age. Our investigations show that plasma ganglioside concentration may reflect the development and maturation of the central nervous system to some degree, at least early in the neonatal period.

Laser pumping by PFN power source.

The use of a pulse forming network (PEN) as a main discharge power supply was tested in a electron-beam-controlled CO(2) laser amplifier in order to improve the utility efficiency of the energy in storage capacitors. The impedance of the pumping discharge through the laser gas was controlled by the accelerating voltage of the electron beam to match the PFN line impedance. In the matched condition all of the stored energy in the PFN was transffered to the laser gas at a constant electric field strength which was optimum for laser pumping.

Successful surgical treatment of a large mixed pial-dural arteriovenous malformation.

A large mixed pial-dural arteriovenous malformation was successfully treated by surgical resection and occlusion of the draining veins. Treatment of this type of malformation is discussed.

Trauma-induced linear scleroderma.

Linear scleroderma (linear morphea) is a form of localized scleroderma characterized by sclerotic lesions distributed in a linear, band-like pattern. Despite its benign course, the disease can cause severe cosmetic, orthopedic, and psychologic problems. The cause is unknown. Many cases are preceded by a history of trauma. We describe a case in which linear scleroderma occurred following a laceration to the affected site. We review the treatment options and discuss the current theories regarding the pathogenesis of the disease.

Effects of a high-protein diet on mineral metabolism and struvite activity product in clinically normal cats.

OBJECTIVE: To examine effects of high-protein diets (> 50% crude protein of dry matter) on urinary mineral excretion and struvite activity product ([Mg2+] x [NH4+] x [PO(4)3-]). ANIMALS: 14 clinically normal cats, 4 adult female and male cats for experiments 1 and 2, respectively, and 6 female kittens aged 4 months for experiment 3. PROCEDURE: Relations between dietary protein amount (25.9, 38.3, 51.4, and 65.4% crude protein [dry matter]) and urinary excretion of Mg, P, and Ca were examined in a 4 x 4-Latin square design (experiment 1). Struvite activity product, the index of solubility of struvite crystals, was determined when a high-protein diet (54.9%) was fed (experiment 2). Utilization of minerals in cats fed a high-protein diet long term was examined (experiment 3). RESULTS: Water intake and urine volume increased with increasing dietary protein concentration. Urinary Mg2+ excretion was not affected (experiment 1) or was decreased (experiment 3) by higher protein intake, leading to lower urine Mg2+ concentration in groups fed higher protein amounts. Urine pH was decreased by high-protein intake. As a result, PO(4)3- concentration was decreased by high-protein intake (experiment 2), although total daily urinary excretion of P was increased. Consequently, struvite activity product tended to decrease in cats fed high-protein diets, indicating increase in struvite solubility. High-protein intake decreased Ca and P retention by increasing their fecal and urinary excretions, respectively. CONCLUSION: As a consequence of the increase in urine volume and urine acidification, high-protein diets have potential ability to increase solubility of struvite crystals.

ESR cavities for in vivo dosimetry of tooth enamel.

TM110 mode and TE111 mode ESR microwave cavities for in vivo human tooth dosimetry are developed. ESR signal from a sample is measured by using microwave leak from the pin hole on the cavity wall. The minimum detectable dose of 2 Gy is obtained by the signal accumulation for 100 sweeps.

ESR dosimetry of a deceased radiation worker.

A case of overexposure of an industrial radiographer using 192Ir sources and having a filmbadge dosimeter record of 104 mSv has been examined with ESR dosimetry of postmortem tooth and bone specimens. ESR measurements of the tooth enamel showed an intense signal of CO2- and gave the equivalent dose (ED) of 14 Gy by the additive dose method using gamma-rays from a source of 60Co. The doses for a finger bone and humerus were 14.7 and 7.0 Gy, respectively. It was concluded that he had been exposed to radiation repeatedly over 10 yr and that ESR dosimetry can give a life-long cumulative dose for personnel using radiation.

[Basilar bifurcation aneurysm associated with internal carotid artery occlusion. Report of two cases].

Two cases of subarachnoid hemorrhage caused by rupture of a basilar bifurcation aneurysm associated with occlusion of the internal carotid artery (ICA) at the neck are presented. Case 1, a 71-year-old female, was hospitalized in a coma. Angiography demonstrated occlusion of the bilateral ICA, collateral blood supply through the branches of the foramen rotundum or vidian artery from the maxillary arteries and right posterior communicating artery, and a saccular aneurysm at the basilar bifurcation. The patient died 1 month later following rerupture of the aneurysm. Case 2, a 64-year-old male, was hospitalized for drowsiness. Angiography showed occlusion of the right ICA, collateral blood supply through a tortuous artery (a vidian artery), and a large aneurysm at the basilar bifurcation. Posterior circulation supplied anteriorly through the right posterior communicating artery. The patient died 1 month later because of rerupture of the aneurysm. Laminar thrombosis of the right ICA and an anastomotic vessel, seemingly a branch of the foramen rotundum or a vidian artery, were demonstrated by autopsy. The combination of cerebral aneurysm and collateral circulation is extremely rare in cases of occlusion of the ICA. The two cases described here suggest that hemodynamic stress is an important factor in the formation of cerebral aneurysms.