Short-term changes in temporomandibular joint function in subjects with cleft lip and palate treated with maxillary distraction osteogenesis.

OBJECTIVES: To investigate the short-term effects of maxillary distraction osteogenesis (DO) on temporomandibular joint (TMJ) function in 21 subjects with cleft lip and palate (CLP). Design - Morphological changes in the maxillofacial region were measured using lateral cephalometric radiographs taken immediately before (pre-DO) and after DO (post-DO) and 1 year after DO (1-year follow-up). A questionnaire was evaluated using a visual analog scale. A chi-square test was used to compare the prevalence of TMJ symptoms between pre-DO and 1-year follow-up. The Spearman correlation coefficient was used to determine the correlation between changes in cephalometric variables and TMJ symptoms in association with maxillary DO. Statistical significance was set at p < 0.05. Results - The ANB (anteroposterior relationship of the maxilla with the mandible) angle and the mandibular plane angle at pre-DO, post-DO, and 1-year follow-up were -4.3 degrees , +5.8 degrees , +4.3 degrees and 32.1 degrees , 33.5 degrees , 33.6 degrees , respectively. The average amounts of anterior and downward movement of the maxilla at post-DO and 1-year follow-up were 8.3, -1.3 and 0.9, 1.1 mm, respectively. The prevalence of TMJ symptoms showed no significant increase in association with maxillary DO. Moreover, there was no significant correlation between changes in cephalometric variables and TMJ symptoms. Conclusion - These results suggest that there was no short-term (i.e., up to 1 year after DO) effect of maxillary DO on TMJ function in subjects with CLP.

Optical design of a hollow cube-corner retroreflector for a geosynchronous satellite.

The optical characteristics of a single-element hollow cube-corner retroreflector for a geosynchronous satellite were numerically evaluated for laser ranging and laser long-path absorption measurements of atmospheric species. An optical design with spherical surfaces and tuned dihedral angles was considered to compensate for velocity aberrations. The parameters for the retroreflector were optimized with genetic algorithms for different retroreflector sizes and wavelengths (500 nm and 1, 3, and 10 microm). We found that 20-cm retroreflectors are sufficient for realistic measurements when the laser wavelength is 500 nm or 1 microm. However, a larger retroreflector is necessary to overcome the detector noise level at 3 and 10 microm.

Effects of protein kinase and phosphatase inhibitors on slow shortening of guinea pig cochlear outer hair cells.

The intracellular mechanisms of slow shortening in isolated guinea pig cochlear outer hair cells were investigated using inhibitors and/or an activator of protein kinases and protein phosphatases. The slow shortening was induced by tetanic electrical field stimulation, and changes in the cell length, volume and intracellular Cl- concentration were microscopically monitored using a chloride-sensitive fluorescent dye. The slow shortening was inhibited by a calmodulin inhibitor, W-7, and a calcium calmodulin-dependent protein kinase II (CaMKII) inhibitor, KN-62. The inhibition by W-7 or KN-62, was abolished by the supplemented conductance of K+ with valinomycin. Among the protein phosphatase inhibitors tested, a type 1 and 2A protein phosphatase inhibitor, calyculin A, inhibited the slow shortening. The inhibition by calyculin A was abolished by the increased Cl- permeability, but neither by the increased K+ conductance with valinomycin nor by the increased Ca2+ conductance with A23187. A protein serine/threonine phosphatase activator, N-acetylsphingosine, inhibited the shortening, which was abolished by either valinomycin or a type 2A protein phosphatase inhibitor, okadaic acid, but not by calyculin A. These findings suggest the following signaling mechanisms in the slow shortening of outer hair cells; the K+ channel opening is facilitated through protein phosphorylation by CaMKII and suppressed via okadaic acid-sensitive dephosphorylation, and the Cl- channel opening depends on calyculin A-sensitive protein phosphatase activity.

Design of a Four-Element, Hollow-Cube Corner Retroreflector for Satellites by use of a Genetic Algorithm.

A four-element retroreflector was designed for satellite laser ranging and Earth-satellite-Earth laser long-path absorption measurement of the atmosphere. The retroreflector consists of four symmetrically located corner retroreflectors. Each retroreflector element has curved mirrors and tuned dihedral angles to correct velocity aberrations. A genetic algorithm was employed to optimize dihedral angles of each element and the directions of the four elements. The optimized four-element retroreflector has high reflectance with a reasonably broad angular coverage. It is also shown that the genetic algorithm is effective for optimizing optics with many parameters.

[Delayed hypoxia after the surgical correction of femoral neck fracture].

We investigated perioperative blood gas changes in 26 patients scheduled for surgical correction of femoral neck fracture under epidural anesthesia. Arterial blood gases during spontaneous air respiration were measured eight times during the femoral neck prosthetic replacements (n = 16), and four times during osteosynthesis (n = 10). In the patients who received femoral neck replacements using bone cement (n = 8), arterial oxygen tension decreased significantly four hours after insertion of prosthesis, and did not recover during two postoperative days. In contrast, in the patients who received cementless femoral neck replacements (n = 8), arterial oxygen tension tended to decrease but not significantly, and returned to normal on the second postoperative day. In the patients who received osteosynthesis, arterial oxygen tension did not change. We suspected that the causes of delayed hypoxia in the femoral neck replacements were vascular endothelial cell injury in the lung by free fatty acid originating from fat embolism, and/or microthrombosis resulting from activated coagulation system. Bone cement was thought to intensify fat embolism because of elevated intramedullary pressure in the femur.

Atrial natriuretic peptide stimulates Cl- transport in retinal pigment epithelial cells.

To study the regulatory role of atrial natriuretic peptide (ANP) on the Cl- transport activity of retinal pigment epithelial (RPE) cells, RPE cells from rabbits were cultured and exposed to ANP and other reagents under perfusion. The changes in intracellular Cl- concentration ([Cl-]i) were continuously recorded using a Cl(-)-sensitive fluorescent dye. The cGMP content was estimated by radioimmunoassay. ANP increased the cGMP content and the [Cl-]i in RPE cells. A guanylate cyclase activator, nitric oxide, and a cell permeable cGMP precursor, 8-Br-cGMP, also increased the level of cGMP and the [Cl-]i. A guanylate cyclase inhibitor, LY83583, an inhibitor of cGMP-dependent protein kinase, KT5823, and an inhibitor of Na+/K+/2Cl- cotransporter, bumetanide, diminished or abolished the ANP-induced increase in [Cl-]i. ANP facilitates Cl- accumulation in RPE cells, which is mediated by guanylate cyclase, cGMP-dependent protein kinase, and the Na+/K+/2Cl- cotransporter.

Adrenergic receptor-mediated Cl- transport in rabbit corneal endothelial cells.

Adrenoceptor-mediated Cl- transport in cultured rabbit corneal endothelium was examined using a Cl(-)-sensitive fluorescent dye. The intracellular Cl- concentration ([Cl-]i) in the endothelial cells was estimated to be about 30 mM. Noradrenaline (0.001-0.1 mM) transiently decreased the [Cl-]i in a dose-dependent manner. Such a decrease in [Cl-]i was completely antagonized by pretreatment with the alpha-adrenoceptor antagonist phentolamine (0.1 mM). The selective alpha 2-adrenoceptor agonist UK 14304-18 (5-bromo-6-[(4H,5H-imidazol-2-yl)amino]quinoxaline, 0.1 mM) persistently decreased the [Cl-]i, but neither the alpha 1-adrenoceptor agonist phenylephrine (0.1 mM) nor the beta-adrenoceptor agonist isoproterenol (0.1 mM) had any effect. The alpha 2-adrenoceptor agonist/antagonist yohimbine (0.1 mM) persistently and more strongly decreased the [Cl-]i than UK 14304-18 did. The yohimbine-induced decrease in the [Cl-]i was not further altered by UK 14304-18 or phenylephrine, but partly reversed by noradrenaline, isoproterenol and an adenylate cyclase activator, forskolin (0.1 mM). The yohimbine-induced decrease in [Cl-]i was inhibited by the carbonic anhydrase inhibitor acetazolamide (1 mM), and Cl-/HCO3- exchange inhibitors, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid, but not by the H(+)-ATPase inhibitor N,N'-dicylohexylcarbodiimide. The forskolin-induced recovery in [Cl-]i was inhibited by the Na+/K+/Cl- cotransport inhibitor bumetanide (0.1 mM), but not by the Cl- channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoic acid.(ABSTRACT TRUNCATED AT 250 WORDS)

Retroreflector with acute dihedral angles.

An acute-angle retroreflector having three dihedral angles of 45, 60, and 90 deg was studied by use of the ray-trace method. Incident rays are reflected nine times in the retroreflector, and there are 26 different sequences for reflections. Errors in the dihedral angles will cause the directions of the reflected rays to diverge. A possible application of the acute-angle retroreflector is in target design for laser ranging.

Long-path absorption measurement of CO(2) with a Raman-shifted tunable dye laser.

A laser long-path absorption system was developed with a hydrogen Raman shifter pumped by a tunable dye laser. The absorption spectrum of CO(2) in the 2-µm region was measured in the open air with a retroreflector or a hard target. The concentration of CO(2) was determined from the spectrum by the least-squares method. Noise in the system was analyzed, and the propagation of error to the obtained concentration was investigated. The statistical error in the concentration was estimated at approximately 1% for a single spectrum measurement. Comparison with the simultaneous measurements with a nondispersive infrared gas analyzer showed good agreement.

Delayed shortening and shrinkage of cochlear outer hair cells.

Slow shortening of cochlear outer hair cells has been speculated to modify cochlear sensitivity. Tetanic electrical field stimulation of isolated outer hair cells from guinea pigs shortened the cells for 2-3 min. Electrical stimulation reduced cell length and volume (-13.5 +/- 1.5 and -37.3 +/- 3.0% of initial values, respectively, n = 16) and decreased the intracellular Cl- concentration. Cytochalasin B (100 microM) inhibited electrical stimulation-induced shortening but not volume reduction. The following chemicals or manipulations inhibited the responses: 10 microM furosemide, 0.1 mM 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), 1 mM anthracene-9-carboxylic acid (AC9), 25 mM tetraethylammonium, 2.3 microM charybdotoxin (ChTX), 250 nM omega-conotoxin, and Ca(2+)-free medium. These findings suggest that both electrical stimulation-induced shortening and shrinkage of outer hair cells result not only from an actin-mediated contractile force, but also from Cl- efflux through furosemide-, DIDS-, and AC9-sensitive Cl- channels, and K+ efflux through ChTX-sensitive K+ channels.

Optical design of cube-corner retroreflectors having curved mirror surfaces.

The characteristics of retroreflectors that include curved mirror surfaces are theoretically investigated. The use of curved mirror surfaces in a cube-corner retroreflector is an effective method for diverging the reflected beam, especially in a large-aperture hollow retroreflector. The effect of curved surfaces is demonstrated for simple examples that give circular and elliptical wave-front patterns. The method was applied in the optical design of a satellite retroreflector in space, which is to be loaded on the Japanese polar orbit Advanced Earth Observing Satellite.

An ATP-driven Cl- pump regulates Cl- concentrations in rat hippocampal neurons.

To investigate the role of Cl(-)-stimulated Mg(2+)-ATPase (Cl(-)-ATPase) in neurons, we examined the effects of ethacrynic acid (0.3 mM), which completely inhibits Cl(-)-ATPase on the intracellular Cl- concentrations of cultured rat hippocampal neurons, using Cl(-)-sensitive fluorescent probes. Ethacrynic acid and ATP consuming treatment increased the intracellular Cl- concentration, but elevation of the extracellular K+ concentration up to 10 mM, inhibition of Na+/K(+)-ATPase, or dissolution of H+ gradients had no effect. Furosemide (0.1 mM), an inhibitor of Na+/K+/Cl- co-transport, decreased the intracellular Cl- concentrations. These results indicate that an ethacrynic acid-sensitive and ATP-driven Cl- pump functions to reduce intraneural Cl- concentrations.