Ethanol injection sclerotherapy for Baker's cyst, thyroglossal duct cyst, and branchial cleft cyst

Six patients with Baker's cysts, 3 with branchial cleft cysts, and 2 with thyroglossal duct cysts were treated with percutaneous aspiration and absolute ethanol sclerotherapy using a 7-French pigtail catheter. Cystography was performed before ethanol injection to confirm that there was no extravasation and that it was a monocystic lesion. One recurrence of a Baker's cyst was revealed in follow-up examinations, which ranged from 11 months to 36 months (mean, 25 months). The major complication of hypoesthesia of the popliteal region was observed in 1 patient treated for Baker's cyst. The results of this series suggest that ethanol sclerotherapy is the treatment of choice for Baker's cyst, branchial cleft cyst, and thyroglossal duct cyst.

Radial arm maze behavior in mice when a return to the home cage serves as the reinforcer

Male ddY mice were housed in a cage with an eight arm radial maze apparatus for 6 h a day. A water bottle was placed at the central platform. The end of each arm ran to the home cage through a guillotine door (G). Food was placed at the home cage. During the housing in the apparatus, one G was raised and the remaining seven G were lowered. The raised G was changed every 45 min in random order. Mice housed in this apparatus learned efficient strategy to return the home cage by trial and error. When they chose the arm in which the G was lowered on their way to the home cage from the platform, they returned to the platform, then chose a different arm until they were able to enter the home cage. The mice housed in this apparatus mastered the radial maze task on the 7th day. When scopolamine (SCO) was injected, SCO butylbromide had no effect on performance, but SCO hydrobromide (0.2 and 0.4 mg/kg) impaired working memory, dose dependently. These results show that the apparatus is useful for ease in estimating working memory in mice without the use of severe food or water deprivation.

Rapid HPLC assay with coulometric detection for norepinephrine and 3-methoxy-4-hydroxyphenylglycol in the mouse brain

For the rapid assay of norepinephrine (NE) and its major metabolite, 3-methoxy-4-hydroxyphenylglycol (MHPG) in the mouse brain, we developed a simple method using isocratic HPLC with coulometric detection. This method permits NE and MHPG assay within 5 min in one chromatographic run. Within-run coefficients of variation for NE and MHPG in the working standard solution were 0.8% and 0.6% (n = 50), respectively. The detector responses were linear from 0.025 to 100 pmol for NE and from 0.05 to 100 pmol for MHPG in the working standard solution. Using this method, the NE and MHPG concentrations were measured in discrete brain areas of the mouse prior treatment with or without alpha-methyl-p-tyrosine or N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4).

Effects of nefiracetam on deficits in active avoidance response and hippocampal cholinergic and monoaminergic dysfunctions induced by AF64A in mice

The effects of nefiracetam [DM-9384; N-(2,6-dimethyl-phenyl)-2-(2-oxo-pyrrolidinyl)acetamide] and of phosphatidylcholine on a step-up active avoidance response, locomotor activities and regional brain cholinergic and monoaminergic neurotransmitters in AF64A-treated mice were investigated. Intracerebroventricular (i.c.v.) injection of AF64A (ethylcholine mustard aziridinium ion; 8 nmol/ventricle) impaired acquisition and retention of the avoidance task, and increased vertical and horizontal locomotor activities. Regional levels of acetylcholine, noradrenaline, 3-methoxy-4-hydroxyphenylglycol (MHPG), 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) were significantly decreased and homovanillic acid (HVA) levels were increased in the hippocampus but not in the septum, cerebral cortex or striatum of AF64A-treated animals. Administration of nefiracetam (3 mg/kg, p.o.) twice daily for 9 days to AF64A-treated animals ameliorated the deficit in active avoidance response in addition to attenuating the increase in locomotor activities. In parallel with these behavioural effects, nefiracetam reversed AF64A-induced alterations in the hippocampal profiles of cholinergic and monoaminergic neurotransmitters and their metabolites. In contrast, administration of phosphatidylcholine (30 mg/kg, p.o.) twice daily for 9 days had no significant effect on the deficit in active avoidance response, despite significantly reversing the decrease in acetylcholine levels in the hippocampus. These results indicate that the effects of nefiracetam on AF64A-induced behavioural deficits are probably due to its ability to facilitate both cholinergic and monoaminergic neurotransmitter systems.

Subgingival plaque formation on single and polycrystal aluminum ceramics

A study was conducted to investigate subgingival plaque formation on two types of dental implant material in the human oral cavity. Fifteen teeth affected by severe periodontitis and scheduled for extraction in five patients were selected. After thorough root planing, inlay cavities were prepared from the gingival margin to 5 mm subgingivally. Then, rectangular test specimens (polycrystal aluminum ceramic (P), single-crystal aluminum ceramic (S)) or a control dentin specimen (D) were installed in gold inlays, which were placed in the inlay cavities and left for 3, 7 or 21 d. As a consequence, 4 mm of the surface of each specimen was exposed to the environment of the periodontal pocket. After each test period, the specimens were removed from the inlays and examined by scanning electron microscopy (SEM). The results suggested that S is a more suitable dental implant material than P from the viewpoint of clinical application because of its lower degree of plaque accumulation.

The inhibitory effect of endotoxins on growth of human cell lines

A study was conducted to examine the effect of endotoxin present in periodontal pockets on the proliferation and attachment of human cell lines on the culture plates (Ca9-22 and gingival fibroblasts). The endotoxin was collected from periodontal pockets of anterior teeth in patients with periodontal disease by subgingival irrigation with sterilized distilled water. The solutions obtained were then subjected to hot phenol-water extraction. The collected endotoxin from periodontal pocket and four other kinds of endotoxin obtained commercially as positive controls were added to cell cultures and the numbers of viable cells on the culture plates were counted. Among the commercially available endotoxins used in this study, only 500 micrograms/ml of endotoxin derived from Escherichia coli 0111:B4 significantly decreased the number of attachment cells of Ca9-22 and gingival fibroblasts on the culture plates. Endotoxin from periodontal pockets at 5 micrograms/ml also significantly decreased the numbers of attachment cells of both cell lines.

MKC-231, a choline uptake enhancer, ameliorates working memory deficits and decreased hippocampal acetylcholine induced by ethylcholine aziridinium ion in mice

The effects of acute and chronic administration of MKC-231, a new choline uptake enhancer, and two other nootropic agents, linopiridine (Dup 996) and tetrahydroaminoacridine (THA) on working memory deficits and decreased hippocampal acetylcholine (ACh) content were studied in a delayed non-matching to sample task, using a T-maze, in ethylcholine aziridinium ion (AF64A)-treated mice. Treatment with AF64A (3.5 nmol, i.c.v.) produced memory deficits and decreased hippocampal ACh content. In acute behavioral experiments, MKC-231 and THA had no significant effect on AF64A-induced memory deficits at any doses tested (0.3, 1.0 and 3.0 mg/kg), whereas Dup 996, at a dose of 1.0 mg/kg, significantly improved memory deficits. In chronic experiments, MKC-231 improved memory deficit at all doses tested (0.3, 1.0, or 3.0 mg/kg p.o., once daily for 11 days) and Dup 996 did so only at a dose of 3.0 mg/kg, whereas THA did not improve memory deficit at any doses tested. In acute neurochemical experiments, MKC-231 and THA did not reverse the AF64A-induced hippocampal ACh depletion. Dup 996, however, further decreased hippocampal ACh content compared to that in the AF64A-treated group. In chronic experiments, MKC-231 significantly reversed hippocampal ACh depletion at doses of 0.3 and 1.0 mg/kg, whereas neither Dup 996 nor THA reversed hippocampal ACh depletion at any doses tested. These results indicate that MKC-231 improved the AF64A-induced working memory deficit and hippocampal ACh depletion, probably by recovering reduced high-affinity choline uptake and ACh release.

[A method employing housing in a radial maze apparatus for estimating working memory in mice: effects of scopolamine and delay upon maze performance]

Male ddY mice were housed in a 4-, 6-, or 8-arm radial maze apparatus for 6 hr a day and then removed to a normal cage for fasting until the next day's trial. A water bottle was placed at the central platform. The end of each arm ran to the home cage through a guillotine door (G). Food was placed in the home cage. During the housing in the apparatus, one G was opened, and the remaining Gs were shut. The opened G was changed in random order during the housing period of 6 hr. At the beginning of the trial, all Gs were shut. The mouse was placed on the platform and was permitted to choose the arms until it chose all arms. When the mouse chose the last arm, the G was opened to allow stepping into the home cage. The mice housed in these apparatus learned to go to the home cage without entering already chosen arms within 4-6 days. Scopolamine (0.2 and 0.4 mg/kg, i.p.) impaired the maze performance. A 1- to 4-min delay impaired the performance slightly, but did not show any significant effect depending on the delay intervals. These results suggest that the apparatus is a useful and easy method for estimating working memory and the drug effects thereon in mice.

Effects of Nd:YAG laser radiation on removal of a root surface smear layer after root planing: a scanning electron microscopic study

A scanning electron microscopy (SEM) study was conducted to evaluate the effects of Nd:YAG laser radiation on removal of a root surface smear layer after root planing in comparison with citric acid treatment. The experimental materials were 15 human teeth affected by severe periodontal disease, which were extracted because of a hopeless prognosis. The teeth had at least 5 mm of attachment loss on the proximal surface tested. After removing all visible calculus using an ultrasonic scaler, each proximal surface was vigorously scaled and root planed with a Gracey curet. Thirty specimens were cut from the root-planed proximal surfaces and assigned randomly to one of two groups: Group A (25 specimens) was divided into 5 subgroups and irradiated with a Nd:YAG laser, using non-contact delivery (3 mm beam diameter, distance from the tip to the specimen 5 cm), at a measured power of 20 W for 0.3, 0.5, 1.0, 2.0, or 3.0 seconds corresponding to energy densities of 84.93, 141.54, 283.09, 566.17, or 849.26 J/cm2; Group B (5 specimens) was not irradiated, but treated for 3 minutes with saturated citric acid (pH 1). The center of each specimen in Group A was used as the experimental area (Exp A) treated by laser irradiation and the peripheral area of the specimen served as a control (Cont A). In Group B, one half of the specimen was used as the experimental area (Exp B) treated by citric acid and the other half served as a control (Cont B). The specimens were then fixed and examined by SEM. The surface of the root-planed specimens (Cont A and B) was irregular, corresponding to the presence of a smear layer, and had an amorphous appearance. Both root surfaces of Exp A and B exhibited clear orifices of dentinal tubules and intertubular dentin without a smear layer. Although the root surface of Exp A showed clear orifices of dentinal tubules with a flat morphology, the root surface of Exp B showed widened funnel-shaped dentinal tubule orifices with a fibrillar, mat-like morphology. The present results indicate that Nd:YAG radiation effectively removes the smear layer, uncovers dentinal tubules, and exposes collagen fibers on the root surface without widening the orifices of dentinal tubules after root planing.

Alpha-sialyl cholesterol reverses AF64A-induced deficit in passive avoidance response and depletion of hippocampal acetylcholine in mice

1. The effect of alpha-sialyl cholesterol (alpha-SC; alpha-D-N-acetylneuraminyl cholesterol) on disturbances of the central cholinergic system induced by ethylcholine mustard aziridinium ion (AF64A) and by scopolamine were studied by means of a step-down passive avoidance response and locomotor activities in mice. The levels of acetylcholine (ACh) in certain regions of the brain were measured to assess the neurochemical recovery promoted by alpha-SC. 2. Treatment with AF64A (2.5, 5 and 10 nmol, i.c.v.) impaired the 24 h retention latencies of animals in a dose-dependent manner, and scopolamine (0.5 mg kg-1, i.p.) also impaired the retention performance. Administration of alpha-SC (1 and 4 mg kg-1, p.o.) once daily for 13 days improved the retention performance in AF64A-treated animals in a dose-dependent manner, but not in the scopolamine-treated animals. 3. Treatment with AF64A (2.5, 5 and 10 nmol, i.c.v.) and scopolamine (0.5 mg kg-1, i.p.) increased vertical and horizontal locomotor activities. alpha-SC dose-dependently attenuated the increase in locomotor activities induced by 2.5 nmol of AF64A, but not the locomotor activities caused by 5 or 10 nmol of AF64A, or scopolamine (0.5 mg kg-1, i.p.). 4. The deficit retention performance of AF64A-treated animals was associated with depletion of ACh levels in the hippocampus, but not in the septum or cerebral cortex. Administration of alpha-SC to AF64A-treated animals dose-dependently reversed the depletion of ACh levels in the hippocampus. 5. The results indicate that alpha-SC had significant effects after oral administration of AF64A-treated animals. The behavioural recovery promoted by alpha-SC may be based on the reversal of ACh depletion in the hippocampus.

Delayed suppressive effect of a low dose of caerulein on the grooming behavior induced by the D1-receptor agonist SKF 38393

Caerulein (CLN, 0.8-80 micrograms/kg, s.c.) was administered to male rats 10 min or 24 hr before the injection of SKF 38393 (3 mg/kg, i.p.). The increased mouth movement and grooming behavior by SKF 38393 were suppressed dose-dependently by CLN 10 min before the SKF 38393. CLN at the dose of 0.8 micrograms/kg, given 24 hr before the SKF 38393, suppressed the grooming behavior by SKF 38393. These findings suggest that a low dose of CLN, but not a high dose, had a delayed suppressive effect on the grooming behavior induced by an excess of D1-activity.

Pharmacological properties of ceruletide in the vertical and horizontal locomotor activities of mice

To clarify the pharmacological properties of ceruletide (CER) and cholecystokinin-octapeptide (CCK-8) with respect to vertical (VLA) and horizontal (HLA) locomotor activities of mice, effects of pretreatment with CER (0.5, 5, and 50 micrograms/kg, IP) and CCK-8 (5, 50, and 500 micrograms/kg, IP) on apomorphine (0.1 mg/kg, SC)- and clonidine (0.1 mg/kg, SC)-induced hypo-VLA and -HLA and on apomorphine (1 mg/kg, SC)-induced hyper-VLA and -HLA were examined. CER and CCK-8 had a dose-dependent inhibitory effect on VLA and HLA in intact mice. Pretreatment with CER had a biphasic effect (increase and decrease) on apomorphine- and clonidine-induced hypo-VLA, as well as an effect on apomorphine-induced hypo-HLA, a decreased effect on clonidine-induced hypo-HLA, and a decreased effect on apomorphine-induced hyper-VLA and -HLA. On the other hand, pretreatment with CCK-8 had no effect on apomorphine- and clonidine-induced hypo-VLA and -HLA and a decreased effect on apomorphine-induced hyper-HLA but not on hyper-VLA. These results suggest that for apomorphine- and clonidine-induced locomotion in mice CER has pharmacological properties different from those of CCK-8.

Reversal by 3,3?,5-triido-l-thyronine of the working memory deficit, and the decrease in acetylcholine, glutamate and ?-aminobutyric acid induced by ethylcholine aziridinium ion in mice

The effect of 3,3',5-triiodo-L-thyronine (T3) on working memory in ethylcholine aziridinium ion (AF64A)-treated mice was studied in a delayed non-matching to sample task using a T-maze. After behavioural testing was completed, mice were killed by microwave irradiation and regional brain levels of acetylcholine, aspartate, glutamate, glutamine, glycine, taurine, and gamma-aminobutyric acid (GABA) were measured by high-performance liquid chromatography with electrochemical detection. Treatment with AF64A (7 nmol, i.c.v.) produced a deficit in working memory performance in the non-matching to sample task at 30 s delay, and decreased acetylcholine, glutamate, and GABA levels in the hippocampus, but not in the septum and cerebral cortex. Administration of T3 (0.3 mg/kg, p.o., once daily for 6 days) to AF64A-treated animals improved the deficit in working memory performance and reversed the decrease in acetylcholine, glutamate, and GABA levels in the hippocampus. These results indicate that the deficit in performance induced by AF64A can be improved by T3 administration.

A simple T-maze method for estimating working memory in mice. Effect of ethylcholine mustard aziridinium ion (AF64A)

Mice were housed in a cage containing a T maze. A watering place was located at the entrance of the maze. The right and left arms of the maze each had two exits, one of which led to the home cage where food was placed, while the other led to the watering place via a bypass. The exit leading to the home cage in either the right or left arm was alternately closed every 90 min. One-way swinging doors were inserted at the entrance to each arm and between each bypass and the watering place. The mice were given a cholinergic neurotoxin--ethylcholine mustard aziridinium ion (AF64A)--(8 nmol) or saline as a control into the left ventricle 2 weeks before they were housed in the apparatus. Those mice housed in this apparatus mastered the alternation task at a 5-sec delay on day 3 in the sham group and on day 4 in the AF64A group. When a longer delay (5-90 sec) was introduced for the mice that mastered the alternation task at 5-sec delay, the AF64A group made significantly more errors than did the sham group at 60- and 90-sec delays. These results show that the apparatus is useful in estimating working memory in mice with little effort.

A rapid assay for neurotransmitter amino acids, aspartate, glutamate, glycine, taurine and ?-aminobutyric acid in the brain by high-performance liquid chromatography with electrochemical detection

For simultaneous assay of the five neurotransmitter amino acids, Asp, Glu, Gly, Tau, and GABA in brain tissues, a very rapid and simple chromatographic method using high-performance liquid chromatography with electrochemical detection in combination with o-phthalaldehyde derivatization is described. Because the present method permits the determination of these five amino acids within less than five minutes in one chromatographic run, up to 100 samples a working day can be analyzed using an autosampler. Within-run coefficients of variation for these five amino acids were less than 2% (n = 20). The quantitative detection limit was 2.5 pmol for the 5 amino acids. The present method has been applied to the measurement of the five amino acid neurotransmitter levels in several discrete brain regions of mice treated with and without electroconvulsive shock.

Rapid and simultaneous assay of monoamine neurotransmitters and their metabolites in discrete brain areas of mice by HPLC with Coulometric detection

For simultaneous assay of the three monoamine neurotransmitters, norepinephrine, dopamine, and serotonin, and four respective metabolites in brain tissue, a rapid and simple method using high-performance liquid chromatography with coulometric detection is described. Because the present method permits the determination of these target substrates within 10 min or less in one chromatographic run, 150 samples can be analyzed using an autosampler and an integrator in a 24-h period. Within-run coefficients of variation for the target substrates in the standard solution and the whole brain sample were less than 3% and 2% (n = 40), respectively. The quantitative detection limits were 0.01-0.1 pmol. The present procedure was applied to measure the target substrates in several discrete brain areas in mice.

Effects of nefiracetam, a novel pyrrolidone derivative, on brain monoamine metabolisms in mice

The effects of acute and chronic administration of nefiracetam, a pyrrolidone derivative, on monoaminergic neurotransmitter systems in the mouse hippocampus, frontal cortex, hypothalamus, and striatum were studied. The levels of monoamines and of their metabolites were measured by high performance liquid chromatography with electrochemical detection on the first, 7th, and 14th days after nefiracetam was given. The neurochemical effects of nefiracetam were compared with those of oxiracetam and indeloxazine. Acute administration of nefiracetam (10 mg/kg, po) and oxiracetam (10 mg/kg, po) had no effect on the levels of noradrenaline (NA), dopamine (DA), or 5-hydroxytryptamine (5-HT), or on the levels of their metabolites, 3-methoxy-4-hydroxyphenylglycol (MHPG), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA), in any of the regions examined. In contrast, a single dose of indeloxazine (10 mg/kg, po) decreased the levels of MHPG, DOPAC, and 5-HIAA in all regions examined. After chronic administration of nefiracetam (10 mg/kg, po, once daily), the levels of MHPG, DOPAC, and 5-HIAA were higher than control in all regions on the 14th day only. Oxiracetam (10 mg/kg, po, once daily) similarly increased the levels of MHPG, DOPAC, and 5-HIAA in the hippocampus, frontal cortex, and striatum, but not in the hypothalamus. Conversely, indeloxazine (10 mg/kg, po, once daily) decreased the levels of MHPG and 5-HIAA in all regions and the levels of DOPAC and HVA in the hippocampus and striatum as measured on the 7th and 14th days. These results show that nefiracetam has a delayed effect on brain monoaminergic metabolism, and that its effects are similar to those of oxiracetam, but clearly different from those of indeloxazine.

Mice housed in a cage with a maze learn the maze without explicit training

Mice were housed in a cage with a maze. A water tap was placed at the entrance of the maze. The exit of the maze connected with another cage (home cage). Food was placed in the home cage. Three different multiple mazes (types 1-3) were placed. 1) Mice were housed for 10 h a day in the apparatus and then removed to a normal cage for fasting. One trial per day was carried out after fasting for 13 h. In each trial, a mouse was put at the entrance of the maze and then the number of errors and the time till it reached the home cage was counted. Mice reached a learning criterion at Trial 2. 2) Administering scopolamine (0.125-0.5 mg/kg) 30 min before Trial four disturbed the maze work dose dependently in a type 3 maze, the most complex maze among the three, but did not in type 1 and 2 mazes. 3) Administering scopolamine (0.25-1.0 mg/kg) 30 min before Trial 11 to the mouse of the type 3 maze did not disturb the maze work. These results show that a mouse housed in a cage with a maze learns the maze without explicit training and scopolamine can differentially effect performance based upon the degree of training.

[A simple multiple maze test to estimate learning and memory in mice: application to the effect of scopolamine on learning and memory]

The apparatus consists of a home cage, a maze cage and a starting box. A maze with four right-middle-left decisions was placed in the maze cage. The starting box was attached and a water tap was placed at an area corresponding to the entrance of the maze. The exit of the maze and the home cage are connected with a tunnel. Food was placed in the home cage. 1) Mice were housed for 10 hr a day in the apparatus and then removed to another cage for fasting. One trial a day was carried out after fasting for more than 12 hr. In each trial, a mouse was put at the starting box, and then the number of errors (entering a blind alley) and the time until the mouse reached the home cage were counted. The mouse passed through the maze with a small number of errors and time. 2) Administration of scopolamine (0.125-0.5 mg/kg, i.p.) to a mouse that had mastered the maze transiently disturbed the maze performance dose-dependently. 3) Mice were housed for 4 hr a day. Scopolamine (0.25 mg/kg, i.p.) was administered either before or after the housing. Scopolamine disturbed the maze performance in the case of both procedures. These results suggest that the method is useful for estimating the memory in mice.

The enhancement of the hypomotility induced by small doses of haloperidol in the phase of dopaminergic supersensitivity in mice

Dopaminergic supersensitivity in mice was induced by pretreatment with a single injection of haloperidol (4.8 mg/kg). After the pretreatment, further treatment with haloperidol (0.6 or 0.01 mg/kg) was made at varying intervals, and catalepsy, locomotor activity and homovanillic acid (HVA) were measured. The intensity of the supersensitivity was evaluated by enhanced apomorphine (1 mg/kg)-induced climbing behavior. Supersensitivity was displayed on the 2nd and the 4th day. The cataleptogenic effect of haloperidol (0.6 mg/kg) was significantly weakened on the 1st, 2nd and 4th days. The motor inhibitory effect of haloperidol (0.01 mg/kg) increased on the 1st, 2nd and 4th days. Homovanillic acid was measured in the striatum and the prefrontal cortex on the 2nd day. Haloperidol (0.6 mg/kg) increased the concentrations of HVA in both regions of the brain. The increase in the concentrations of HVA in the striatum was blunted after the pretreatment, but such tolerance did not develop in the prefrontal cortex. Haloperidol (0.01 mg/kg) did not influence the concentration of HVA in both regions. These results suggest that the behavioral effect of a small dose of haloperidol may be enhanced, rather than reduced, in the phase of supersensitivity.

The effect of arsenic trioxide on brain monoamine metabolism and locomotor activity of mice

The arsenic trioxide (AsT) content, and monoamine levels in the cerebral cortex, hippocampus, hypothalamus and corpus striatum were determined in mice administered AsT (3 and 10 mg/kg) for 14 days. The vertical and horizontal motor activity was also examined. The AsT content in discrete brain areas differed but was clearly dose-dependent. Metabolites of norepinephrine and dopamine increased in the cerebral cortex, hippocampus and hypothalamus and decreased in the corpus striatum in AsT-treated mice. Metabolites of 5-hydroxytryptamine increased in all the discrete brain areas. The vertical and horizontal motor activity was increased by AsT at 3 mg/kg and decreased by AsT at 10 mg/kg. These results show that AsT modifies CNS metabolism and function at low doses. AsT penetrates the blood-brain barrier to cause these effects.

[A study of the relationship between hearing-aid usage and residual hearing]

Fifty-eight children (from 4 to 19 years of age) with bilateral, symmetrical, sensorineural hearing loss, who had used a hearing aid in only one ear for 1 to 19 years were investigated to study the influence of hearing-aid upon the residual hearing between the used and no used ears. The results were as follows, 1) The average hearing level for the used ear at seven frequencies was 49. 5 dB of pre-hearing-aid usage and was 53. 8 dB of post-hearing-aid usage. The discrepancy of audiograms between the aided and unaided ear was not remarkable. 2) The hearings for both the aided and the unaided ears in Audiograms was progressive for a long time. But no significance relation was observed between changes in used-ear hearing of the aided and unaided ears. 3) When the hearing levels of the children were scrutinised on an individual basis, it was found that 9 cases (15.5%) in both ears, 2 cases (3.4%) in only used ear and 1 case (1.7%) in only no used ear out of 58 cases showed deterioration of hearing. 4) These data did not lead us to the conclusion that hearing-aid usage was detrimental on the residual hearing of children with sensorineural hearing loss.

A case of nephrotic syndrome due to alpha-mercaptopropionyl glycine in a patient with familial cystinuria

A 26-year-old male with nephrotic syndrome (NS) due to alpha-mercaptopropionyl glycine (MPG) is described. In March, 1988, he was diagnosed as having familial cystinuria after receiving urolithiasis treatment since December, 1985. Massive proteinuria and slight pedal edema were noted. Nephrotic syndrome was suggested and renal biopsy was performed. The renal pathological finding demonstrated membranous glomerulonephritis (MN) at stage I. This case was defined as NS clinically associated with MPG, and glucocorticoid intake was initiated. The response to the glucocorticoids was fairly good with no clinical problems after discontinuation of MPG, and the cystinuria was maintained with alkaline medication. The patient's parents and younger brother were suggested and confirmed to have cystinuria based on urinary aminogram analysis, but displayed no symptoms. We present a rare case of NS due to MPG therapy in a patient with familial cystinuria. However, the mechanism of onset remains unclear.

[Some aspects of third molars with regard to the development of malocclusions]

Although the orthodontist is constantly aware of the developing third molar and its possible effects on the dentition during and after orthodontic treatment, the relationship between the third molar and the development of malocclusion had not been resolved. To attempt to clarify some of the problems associated with the third molar, an analysis of the factor in fluencing on the dentition and denture frame was performed. In this study, twenty-one adult cases which had no prothodontic correction of the tooth shape and orthodontic treatment with at least three wisdom teeth were used for evaluation of the denture frame structure and occlusion. The case which impacted third molar (M3 impacted group) showed less than 25 degree mandibular plane angle (FH-MP) without exception, while the case which the third molar erupted (M3 erupted group) were able to divide into high angle (more than 30 degree of FH-MP) and low angle (less than 29 degree of FH-MP) groups. The M3 impacted with low angle group and M3 erupted with low angle group showed relatively normal occlusion and favorable denture frame structure, but M3 erupted with high angle group indicated that the denture frame composition was affected by posterior discrepancy especially the steepness of occlusal plane which might be the over eruption of posterior teeth. The M3 erupted with high angle group also included two cases of severe anterior open-bite with skeletal deformity. These findings suggest that the posterior discrepancy due to existence of third molars influence on the dento-facial-skeletal structure and development of malocclusions.