Phase structure of a surface model with many fine holes.

We study the phase structure of a surface model by using the canonical Monte Carlo simulation technique on triangulated, fixed connectivity, and spherical surfaces with many fine holes. The size of a hole is assumed to be of the order of lattice spacing (or bond length) and hence can be negligible compared to the surface size in the thermodynamic limit. We observe in the numerical data that the model undergoes a first-order collapsing transition between the smooth phase and the collapsed phase. Moreover the Hasudorff dimension H remains in the physical bound, i.e., H < 3 not only in the smooth phase but also in the collapsed phase at the transition point. The second observation is that the collapsing transition is accompanied by a continuous transition of surface fluctuations. This second result distinguishes the model in this paper and the previous one with many holes, whose size is of the order of the surface size, because the previous surface model with large-sized holes has only the collapsing transition and no transition of surface fluctuations.

Simultaneous voiding cystourethrography and voiding urosonography reveals utility of sonographic diagnosis of vesicoureteral reflux in children.

AIM: To evaluate the diagnostic potential of voiding urosonography (VUS) compared with fluoroscopic voiding cystourethrography (VCUG) under identical conditions and to evaluate potential reasons for false-negative VUS results, particularly regarding bladder concentrations of the US contrast agent, Levovist. METHODS: Fifty-six paediatric patients (M/F 34/22, mean age 2.3 y, age range 1 mo-14 y) underwent simultaneous VUS and VCUG under identical conditions. The bladder was filled by simultaneous administration of Levovist and the X-ray contrast medium, DIP Conray. Levovist concentrations in bladders were calculated using amounts of Levovist injected and total DIP Conray infused when reflux was first observed in either procedure. RESULTS: Sensitivities of VUS and VCUG for detection of vesicoureteral reflux (VUR) were both 86%, assuming that VUR detected by either method represented a true-positive, and no reflux by either method represented a true-negative. Patients under 24-mo of age displayed a better VUS sensitivity, of 94%. Levovist concentrations in bladders ranged from 1.8% to 23%, with older children tending to demonstrate increased bladder capacity and lower concentration. All VUS false-negative units displayed Levovist bladder concentrations of less than 5%. CONCLUSION: The present simultaneous study suggests that: 1) the two techniques demonstrate similar sensitivity for detection of reflux; 2) sustained Levovist bladder concentrations of below 5% may not allow detection of reflux on VUS; and 3) VUS represents a suitable technique, particularly for small children whose bladder capacity is not so large.

Bonding to dentin with a self-etching primer: the effect of smear layers.

OBJECTIVE: The purpose of this study was to investigate the effect of smear layers on the tensile bond strength to human dentin. Bond strength was determined on dumbbell-shaped specimens to determine the feasibility for clinical use of a self-etching primer. METHODS: The dentin of extracted human teeth was exposed by grinding with either #180 or #600 abrasive paper. A self-etching primer was then applied to the prepared dentinal surfaces and left undisturbed for 30s. It was then air-dried and a photocured bonding agent applied and irradiated for 20s. A composite resin was then added to the primed dentin and light-cured for 60s to complete the bonded assemblies. Mini-dumbbell specimens (3.0 x 2.0 mm2) were prepared from the bonded samples. These specimens were stored in 37 degrees C water for 24h before tensile loading to failure at a crosshead speed of 1.0 mm/min. Surfaces of fractured specimens, both resin and dentin, were examined under a scanning electron microscope (SEM). RESULTS: Significantly different tensile bond strengths (TBS) of 10.0+/-7.2 and 28.5+/-5.2MPa were found for #180- and #600-prepared dentin, respectively (p<0.01). The former specimens fractured within the hybridized, relatively coarse smear layer, while the latter demonstrated adhesive failure between the composite resin and an attached PMMA rod, not between the dentin and applied adhesive agent. SIGNIFICANCE: The presence and quality of a smear layer yields significantly different bond strengths to prepared human dentin, in vitro. However, a TBS of 10+/-7MPa is evidently adequate, since self-etching primers have been well accepted in dental clinics.

Effects of topical nipradilol, a beta blocking agent with alpha blocking and nitroglycerin-like activities, on intraocular pressure and aqueous dynamics in humans.

AIMS: To study the effects of topical nipradilol, a non-selective beta blocker with alpha blocking and nitroglycerin-like activities, on intraocular pressure (IOP) and aqueous humour dynamics in normal humans and in patients with ocular hypertension. METHODS: Nipradilol (0.06%, 0.125%, 0.25%, 0.5%) was applied to normal volunteers (n = 12) to test for IOP lowering effects. In a second group of normal volunteers (n = 11), nipradilol (0.125% and 0.25%) and timolol (0. 5%) were compared for IOP lowering effects. After a single administration of 0.25% nipradilol, IOP, flare intensity in the anterior chamber, aqueous flow, uveoscleral outflow, tonographic outflow facility, and episcleral venous pressure were either directly measured or mathematically calculated. Topical nipradilol (0.25%) was administered to 24 patients with ocular hypertension twice daily for 8 weeks. RESULTS: Administration of 0.25% nipradilol decreased IOP with a maximum reduction of 4.2 mm Hg lasting 12 hours. A single instillation of both 0.25% nipradilol and 0.5% timolol reduced the IOP in normotensive human subjects to the same degree. A single instillation of 0.25% nipradilol decreased the aqueous flow rate in the treated eye by 20%. Nipradilol produced no significant effect in tonographic outflow facility or episcleral venous pressure, but uveoscleral outflow was increased. In patients with ocular hypertension, twice daily instillation of 0.25% nipradilol decreased IOP without tachyphylaxis for the 8 week test period. CONCLUSION: Topical nipradilol (0.25%) reduced IOP by decreasing the aqueous flow rate and probably also by increasing uveoscleral outflow. Nipradilol should be further investigated as a new antiglaucoma drug.

[Sulfonylureas and daily blood glucose profiles in elderly diabetics].

The aim of this study is to clarify the relationship between the efficacy of sulfonylureas and duration of diabetes in elderly diabetics. Daily blood glucose profiles were measured in 87 Type 2 elderly diabetic patients on sulfonylureas (tolbutamide, gliclazide or glibenclamide). Plasma glucose concentrations were determined at 08.00 (before breakfast), 10.00, 12.00 (before lunch), 14.00, 18.00 (before dinner), 20.00, 24.00, 03.00, 06.00, 08.00 hours. The subjects were divided into 4 sub-groups, according to their duration of the diabetes (< 10, 10-14, 15-19, 20 or more years). Mean plasma glucose values at 08.00, 10.00, 20.00, 03.00 and 06.00 hours were not significantly different among the four groups. However, mean plasma glucose values at 12.00, 14.00, 18.00, 00.00 hours and mean total blood glucose area under the daily profile (total BG) were significantly different among the four groups and the values in patients with a history of diabetes of 15 years or more increased. Duration of diabetes positively correlated with blood glucose values at 12.00, 14.00, 18.00, 00.00, 03.00 hours and total BG, and the dose of sulfonylureas positively correlated with blood glucose values at 12.00, 14.00, 18.00, 00.00 hours and total BG in multiple regression analysis. These results suggest that duration of diabetes and dose of sulfonylureas are important determinants of blood glucose control with sulfonylureas in elderly diabetic patients.

[An elderly case of giant infected liver cyst that decreased dramatically without percutaneous aspiration].

A 70-year-old woman was referred to our hospital for treatment of cholelithiasis. A giant liver cyst (6 cm in diameter) had been diagnosed three years earlier. On admission, she had low grade fever and hepatomegaly. High values were observed for WBC (9900/microliter), CRP (8.9 mg/dl), GPT (45 IU/l), ALP (1399 IU/l), gamma-GTP (333 IU/l) and LAP (249 IU/l). The diagnosis of infected liver cyst (8 cm in diameter) was made based on contrast-enhanced CT scan. Endoscopic retrograde cholangiopancreaticography showed no communication between the cyst and the intrahepatic bile duct. She was successfully managed with antibiotics and discharged without percutaneous aspiration the cyst. On abdominal CT scan 4 months after the discharge, the liver cyst had decreased dramatically in size (1 cm in diameter). The patient remains healthy without symptoms.

[Morning blood glucose determination in the monitoring of metabolic control in type 2 elderly diabetic cases treated by oral hypoglycemic agents].

Daily blood glucose profiles were measured in 163 Type 2 elderly diabetic cases to evaluate whether a fasting (before breakfast) or a post-prandial (after breakfast) blood glucose concentration is able to predict blood glucose values throughout the day. In the diet-treated alone group (n = 61), the percentage of daily blood glucose profiles having plasma glucose values less than the 08:00 hours (before breakfast) value were as follows: 59.0%, 32.8%, 59.0%, and 55.7% at 18.00 (before supper), 24.00, 03.00, 06.00 hours, respectively. In group treated by oral hypoglycemic agents (OHA) (n = 102), these were as follows: 45.1%, 26.5%, 52.9%, and 67.6%, respectively. In the OHA group, the mean plasma glucose value at 08:00 hours was significantly higher in patients with the lowest plasma glucose levels between 60-79 mg/dl than in patients with these levels between 80-99 mg/dl (103.7 +/- 19.6 vs 118.7 +/- 16.9 mg/dl, p < 0.01), but that at 10:00 hours was similar in the two groups (218.8 +/- 43.9 vs 214.5 +/- 40.1 mg/dl). In patients with lowest plasma glucose levels of between 60-99 mg/dl, the 08:00 hours value correlated positively with that of 24:00 (r = 0.40), 03.00 (r = 0.53), and the 06.00 hours value (r = 0.69), but no correlation was observed with the 18.00 hours value. On the other hand, the 10:00 hours value was not associated with these time-points values. Our results reveal that before breakfast plasma glucose values are more predictive of low blood glucose values in the night during sleep than after-breakfast blood glucose values, but do not predict low blood glucose values before supper in patients on OHA.

[Effect of nipradilol on aqueous flow in glaucoma patients treated with timolol].

The effect of nipradilol solution (KT-210) on aqueous flow was evaluated using fluorophotometry in 10 patients (6 primary open-angle glaucoma and 4 ocular hypertension) treated with timolol for more than one month. A single dose of 0.5% timolol was instilled into both eyes at 8 AM, and 0.25% KT-210 or placebo was instilled into both right and left eye at 11 AM; the treated eye was chosen randomly. Aqueous flow was measured every hour from 9 AM to 3 PM. There was no significant difference in pretreatment aqueous flow between the two eyes; 1.98 +/- 0.53 microliters/min in the KT-210 treated eyes, and 1.98 +/- 0.76 microliters/min in the placebo treated eyes. The flow measured 1 to 4 hours after KT-210 instillation was 1.66 +/- 0.69 microliters/min, 2.23 +/- 1.02 microliters/min, 2.20 +/- 0.67 microliters/min, and 1.68 +/- 0.64 microliters/min, respectively. This flow did not differ significantly from the flow in the placebo treated eyes (1.83 +/- 0.86 microliters/min, 1.79 +/- 0.69 microliters/min, 2.26 +/- 0.58 microliters/min, and 1.84 +/- 0.32 microliters/min).

[Anterior chamber dimensions in patients with angle-closure glaucoma measured by an anterior eye segment analysis system].

The corneal curvatures, iridocorneal angles, anterior chamber depths, and anterior chamber volumes in 26 (5 male and 21 female) patients with primary angle-closure glaucoma were measured using an anterior eye segment analysis system (EAS-1000, Nidek). The radius of corneal curvature was 7.65 +/- 0.25 mm (mean +/- standard deviation), significantly smaller than age-matched controls, and the iridocorneal angles ranged between 19 and 21 degrees. The anterior chamber depth and volume of angle-closure glaucoma eyes did not correlate with age; the depth averaged 1.90 +/- 0.41 mm, and the volume averaged 83.3 +/- 28.4 microliters.

Purification and characterization of the Pseudomonas aeruginosa NfxB protein, the negative regulator of the nfxB gene.

The protein NfxB, involved in conferring resistance to quinolones in Pseudomonas aeruginosa, has a helix-turn-helix motif which is similar to that of other DNA-binding proteins. It appears to affect the membrane-associated energy-driven efflux of some antibiotics (H. Nikaido, Science 264:382-388, 1994). We constructed a plasmid that overproduced NfxB in Escherichia coli and purified the protein. Two species of NfxB (23 and 21 kDa), which are probably translated from different initiation codons, were isolated. Both proteins are also expressed in vivo in P. aeruginosa, with the 23-kDa NfxB being the major species. NfxB specifically binds upstream of the nfxB coding region as demonstrated by gel retardation and DNase I footprinting. Expression of the phi (nfxB'-lacZ+) (Hyb) gene was repressed in the presence of the nfxB gene product provided by a second compatible plasmid in E. coli. In the P. aeruginosa wild-type strain (PAO2142), NfxB was undetectable by immunoblotting; however, it was detected in the nfxB missense mutant (PK1013E). These results suggested that NfxB negatively autoregulates the expression of nfxB itself. Since the 54-kDa outer membrane protein (OprJ) (N. Masuda, E. Sakagawa, and S. Ohya, Antimicrob. Agents Chemother. 39:645-649, 1995) was overproduced in nfxB mutants, NfxB may also regulate the expression of membrane proteins that are involved in the drug efflux machinery of P. aeruginosa.

[Anterior chamber dimensions in normal subjects on Kume Island, Okinawa].

The anterior chamber dimension and axial length were studied by photogrammetry and ultrasonography in 365 normal subjects over 21 years of age on Kume island, Okinawa. There was no difference between right and left eyes in the anterior chamber dimensions, corneal curvature, or axial length. Male subjects had a larger anterior chamber and longer axial length than female subjects. The volume, depth, and diameter of the anterior chamber diminished with age and degree of hyperopia. The axial length was related to the anterior chamber dimensions, corneal curvature, and degree of ametropia. The anterior chamber dimensions and axial length in subjects over 60 years of age on Kume island were significantly smaller than in normal subjects over 60 years in Tokyo.

[Newly devised subcutaneous needle electrodes for EMG recording].

Subcutaneous needle electrodes made of stainless steel were newly devised for ease of handling and perfect insulation. This needle (phi 0.20 mm) is used for acupuncture. The electrodes had the capability to record the EMG activity easily from a certain muscle. Then, the EMG activities of the masseter muscle were recorded with both these needle electrodes and surface electrodes and the results were compared. 1. Insertion of the electrodes into the subcutaneous tissue was easily performed because of the application of the acupuncture needle and their lightness of 0.2g was effective in fixing the electrodes on the skin without causing any tension. 2. After the insertion of the needle electrodes, the impedance showed below 5 kohm immediately, and the EMG recordings during biting could be simply achieved with great stability. 3. The action potential from the needle electrodes was less than that from the surface ones. The former reacted more sensitively to the change in the distance between the electrodes, compared with the latter.

[Effects of positions of experimental premature contacts on jaw function].

The effects of different positions of experimental premature contacts on the jaw function were investigated on 6 subjects. The metal castings of 100-microns thickness were fabricated to make experimental premature contacts on each of 4 mandibular posterior teeth (from the first premolar to the second molar on the preferable masticatory side). The EMG activity of the masseter, anterior and posterior temporal muscles during maximum clenching and gum chewing as well as the mandibular movement during gum chewing were evaluated. The experimental premature contacts reduced the muscle activity, especially on the contralateral side during maximum clenching. As the premature contact was moved more posteriorly, the following results were observed. 1. The activity of the posterior temporal muscle was decreased on the ipsilateral side while it increased on the contralateral side during maximum clenching in many subjects. 2. The duration of the occlusion phase during the ipsilateral chewing was shortened in many subjects. 3. During ipsilateral chewing, a larger muscle activity was produced during the closing phase and the muscle activity produced during the occlusion phase was the least on the first molar. 4. In any chewing side, the closing and opening paths tended to go toward the chewing side.