Electron paramagnetic resonance enhanced crystal field analysis for low point-group symmetry systems: C2v sites in Sm3+:CaF2/SrF2.

We present a comprehensive spectroscopic study of C[Formula: see text] point-group symmetry sites in Sm[Formula: see text]:CaF[Formula: see text]/SrF[Formula: see text] codoped with either NaF or LiF. Data includes electron paramagnetic resonance measurements of Zeeman and hyperfine interactions for the ground state, as well as site-selective excitation and fluorescence spectroscopy up to the [Formula: see text]G[Formula: see text] multiplet. Inclusion of the EPR data allowed us to determine unique crystal-field parameters. The parameters provide information about the geometry of the sites and the nature of the interactions between the Sm[Formula: see text] dopant and the alkaline earth co-dopant.

Involvement of IQGAP1, an effector of Rac1 and Cdc42 GTPases, in cell-cell dissociation during cell scattering.

We have previously proposed that IQGAP1, an effector of Rac1 and Cdc42, negatively regulates cadherin-mediated cell-cell adhesion by interacting with beta-catenin and by causing the dissociation of alpha-catenin from cadherin-beta-catenin-alpha-catenin complexes and that activated Rac1 and Cdc42 positively regulate cadherin-mediated cell-cell adhesion by inhibiting the interaction of IQGAP1 with beta-catenin. However, it remains to be clarified in which physiological processes the Rac1-Cdc42-IQGAP1 system is involved. We here examined whether the Rac1-IQGAP1 system is involved in the cell-cell dissociation of Madin-Darby canine kidney II cells during 12-O-tetradecanoylphorbol-13-acetate (TPA)- or hepatocyte growth factor (HGF)-induced cell scattering. By using enhanced green fluorescent protein (EGFP)-tagged alpha-catenin, we found that EGFP-alpha-catenin decreased prior to cell-cell dissociation during cell scattering. We also found that the Rac1-GTP level decreased after stimulation with TPA and that the Rac1-IQGAP1 complexes decreased, while the IQGAP1-beta-catenin complexes increased during action of TPA. Constitutively active Rac1 and IQGAP1 carboxyl terminus, a putative dominant-negative mutant of IQGAP1, inhibited the disappearance of alpha-catenin from sites of cell-cell contact induced by TPA. Taken together, these results indicate that alpha-catenin is delocalized from cell-cell contact sites prior to cell-cell dissociation induced by TPA or HGF and suggest that the Rac1-IQGAP1 system is involved in cell-cell dissociation through alpha-catenin relocalization.

Vacuum ultraviolet spectroscopy of Ce(3+)-doped SrMgF(4) with superlattice structure.

X-ray diffraction of Ce(3+)-doped SrMgF(4) (SMF:Ce) crystals shows a superlattice structure, reflecting the distribution of Ce(3+) polyhedra centres observed in optical experiments. Optical absorption bands and fluorescence bands from the Ce(3+) polyhedra centres overlap in the vacuum ultraviolet (VUV) and ultraviolet (UV) regions, respectively, so that wide pumping and tuning ranges are expected for laser operation. The SMF:Ce crystals, as well as the isomorphous BaMgF(4), are candidates for a tunable laser gain material with nonlinear properties. The optical absorption, excitation, and fluorescence bands observed in the SMF:Ce crystals at low temperatures are ascribed to five distinct fluorescent centres. Three centres have well-known Ce(3+) optical characters, for example, fluorescence with double peaks separated by 2000 cm(-1) and five resolved absorption/excitation bands. These centres are assigned to Ce(3+)-polyhedra classified by weak and strong crystal fields as a consequence of the superlattice structure. The other two fluorescence bands observed in the visible region have 1.5-2 times larger linewidths than those of the former three bands. These bands are interpreted as optical transitions from complexes consisting of Ce(3+) and one or two electrons trapped at a vacancy of the nearest neighbour F(-) ligand ions.

Effects of Nutritional Supplements on Muscle Mass and Activities of Daily Living in Elderly Rehabilitation Patients with Decreased Muscle Mass: A Randomized Controlled Trial.

OBJECTIVE: To investigate the effects of nutritional intervention with resistance training on skeletal muscle mass in elderly patients with disabilities in a convalescent rehabilitation setting. DESIGN: A randomized controlled trial. (UMIN Clinical Trials Registry ID: UMIN000006238). SETTING: A rehabilitation hospital. PARTICIPANTS: 39 elderly patients with decreased skeletal muscle mass in an inpatient convalescence rehabilitation unit. INTERVENTIONS: A combination of resistance training plus nutritional supplementation (R/N group) or resistance training alone (R group). The training and supplementation were conducted essentially from the patient's admission to discharge (2-6 months). OUTCOME MEASURES: The patients were evaluated at the time of admission and at the end of the intervention for skeletal muscle mass (calf circumference [CC] as a primary outcome, and arm circumference [AC]), hand grip strength (HG), Mini-Nutritional Assessment-Short Form (MNA®-SF) score, serum albumin level (Alb), body mass index (BMI), and activities of daily living (ADL) as represented by the Barthel Index (BI) score. RESULTS: Significant treatment effects were seen for CC, AC, BI, Alb in the R/N group compared to the R group. A mean treatment effect of 3.2 (95%CI: 2.0-4.4) was seen in CC, 1.4 (95%CI: 0.8-2.1) was seen in AC, 11.2 (95%CI: 0.5-21.8) was seen in BI, 0.3 (95%CI: 0.1-0.5) was seen in Alb. CONCLUSION: The results of this study suggest that nutritional intervention added to resistance training during convalescent rehabilitation may improve skeletal muscle mass and activities of daily living.

Optical filters inhibiting television-induced photosensitive seizures.

OBJECTIVE: Televised images are the most common stimulus for provoking photosensitive seizures in photosensitive persons. To inhibit photosensitive seizures in photosensitive persons who do or do not have epilepsy, the authors sought nonpharmacologic methods for reducing the levels of photic stimulation of televised images. BACKGROUND: The authors found two types of pathophysiologic mechanisms (wavelength-dependent and quantity of light-dependent mechanisms) for photoparoxysmal responses (PPR). METHODS: The authors tested two different types of optical filters, one reflecting long-wavelength red light selectively, which stimulates a wavelength-dependent mechanism, and the other absorbing light in the visible spectrum evenly (neutral density filters). Inhibiting effects of optical filters were studied by conventional intermittent photic stimulation (IPS) using strobe light and novel photic stimulation using flashing cathode ray tubes (CRT). RESULTS: Both filters individually inhibited PPR insufficiently (less than 50%). Compound optical filters, composed of both types of filters, can inhibit the PPR, approximately 90% for IPS and 95% for photic stimulation with CRT. These compound optical filters do not destroy chromaticity of emissions from the television's CRT. CONCLUSIONS: These compound filters may be useful to prevent seizures induced by television in photosensitive persons.

Symptoms and signs of irritation of the brachial plexus in whiplash injuries.

We investigated the incidence of evidence of irritation of the brachial plexus in 119 patients with whiplash injuries sustained in road-traffic accidents. We compared the symptoms, physical signs, autonomic status, psychological status and findings from radiographs of the cervical spine using examination charts and a modified Cornell Medical Index Health questionnaire, in patients in two distinct groups: those with irritation of the brachial plexus and those without. There were 45 patients (37.8%) in the first group. The ratio of women to men was significantly higher in patients with irritation of the plexus as was the incidence of symptoms other than neck pain. There was no significant difference between the two groups with regard to psychological status or findings in radiographs of the cervical spine. Symptoms and signs attributable to stretching of the brachial plexus do occur in a significant proportion of patients after a whiplash injury. Their presence and persistence are associated with a poor outcome.

Acute stretching of peripheral nerves inhibits retrograde axonal transport.

The conjugation of horseradish peroxidase with wheat germ agglutinin was used to identify the effect on retrograde axonal transport of stretching the rat sciatic nerve indirectly by 10% and 20% femoral lengthening with a unilateral external fixator. To investigate the relationship between retrograde axonal transport and blood flow in the stretched nerve, nerve blood flow in the sciatic nerve was measured by a hydrogen washout technique. At 11% strain (20% femoral lengthening), the numbers of horseradish peroxidase-labelled motor neuron cells and nerve blood flow had decreased by 43% and 50%, respectively. Histological examination demonstrated ischaemic changes, but not mechanical damage. However, at 6% strain (10% femoral lengthening) there were no significant abnormalities. These findings suggest that the inhibition of retrograde axonal transport can be induced by acute stretching of the peripheral nerve and that circulatory disturbance is the main cause of the inhibition of retrograde axonal transport at the low strain.

Quantitative evaluation of sympathetic nervous system dysfunction in patients with reflex sympathetic dystrophy.

The sympathetic nervous system function in 20 patients with reflex sympathetic dystrophy (RSD) of one upper extremity was examined by a non-invasive laser Doppler method to assess fingertip blood flow and vasoconstrictor response to deep inspiration. We observed an increased blood flow but an unchanged vasoconstrictor response in the affected hand in stage 1 of the disorder, but in stage 2 there was a decreased blood flow and a stronger vasoconstriction following an inspiratory gasp. Skin blood flow and vasoconstrictor response returned to normal following successful treatment of the condition. These results suggest that in RSD patients the sympathetic nervous system function is altered and is different in the various stages. The objective method used in our study may be of value in the diagnosis and management of RSD.

Compression and stretching of the brachial plexus in thoracic outlet syndrome: correlation between neuroradiographic findings and symptoms and signs produced by provocation manoeuvres.

In order to investigate the mechanism of nerve irritation in thoracic outlet syndrome (TOS), we studied 150 patients who presented with symptoms of neurologic TOS between 1985 and 1999. They first performed various provocative physical manoeuvres and then underwent injection of contrast medium into the supraclavicular part of the brachial plexus. Several of the provocative manoeuvres were then repeated and radiographs were again obtained. Based on the neuroradiographs, we identified three subsets of patients; those with only compression (type 1 TOS, n=27, 18%), those with combined compression and stretching (type 2 TOS, n=111, 74%), and those with only stretching (type 3 TOS, n=12, 8%). We were able to correlate the neuroradiological subsets with symptoms elicited by pre-radiographic provocative manoeuvres; in 92 patients (61%) these were elicited by traction manoeuvres. We conclude that stretching is an important factor of nerve irritation in TOS.

Fluorine uptake and crystallinity of dentin treated with glass ionomer cement containing tannin-fluoride preparation.

We investigated the fluorine uptake in various layers of bovine dentin treated with glass ionomer cement (GIC) where a tannin-fluoride preparation (HY agent) was incorporated in the cement powder at ratios of 0% (HY0), 1.5% (HY1.5), 5% (HY5), and 10% (HY10) by weight. The crystallinity of the dentin treated with the HY0 and HY10 cements was also investigated. The higher the ratio of incorporated HY agent, the deeper the penetration of fluorine in the dentin, and the greater the amount of fluorine taken up that bonded with the apatite. Compared with total fluorine uptake, more time is needed for fluorine to form a stable bond with apatite. It is also suggested that the crystallinity of dentin is enhanced when exposed to GIC containing the HY agent.

Adhesiveness of glass ionomer cement containing tannin-fluoride preparation (HY agent) to dentin--an evaluation of adding various ratios of HY agent and combination with application diammine silver fluoride.

We bonded a glass ionomer cement (GIC) containing various amounts of incorporated tannin-fluoride preparation (HY agent) to bovine dentin and investigated the effect of the ratio of incorporated preparations and the changes in bond strength over time. HY agent was incorporated into the powder at 0% (HY0), 1.5% (HY1.5), 5.0% (HY5), and 10.0% (HY10) by weight. The shear bond strength and percent of the cohesive failure were measured. Similar tests were performed on samples where diammine silver fluoride was applied to the dentin prior to placing the cement. It was found that the bond strength on the first day was increased by incorporating 1.5% of the HY agent in the GIC. The combined use of diammine silver fluoride increased the bond strength of the GIC.

[A study of autonomic nerve dysfunction in patients with thoracic outlet syndrome].

The function of the autonomic nerve system in sixty-seven patients with thoracic outlet syndrome was examined by a non-invasive and quantitative technique assessing the mean (M) and coefficient of variation (CV) or R-R interval in ECG. The first group of patients (28 cases) with autonomic nervous disorder and complaints of general discomfort showed a significantly shorter M and smaller CV. The second group (39 cases), those without general discomfort, exhibited a normal range of M and CV. In four of the first group with the diagnosis of schizophrenia and anxiety neurosis, furthermore, M and CV were nearly the same as those in the second group. In eight of the first group undergoing decompression operation, their complaints decreased or disappeared after surgery, with recovery of M and CV almost to the normal level. According to these results, this method appears to be useful in differentiating between autonomic nervous disorders and psychological disorders, facilitating disappearance of general discomfort due to autonomic nervous disorders.

A new, modified operation for funnel chest using the Zimmer osteosynthetic plate.

A corrective operation for funnel chest using a Zimmer osteosynthetic plate, which can be bent to any configuration desired, is described. This operative method can be employed for any type of chest deformity in adults and adolescents. A physiologically normal and perfectly stabilized anterior chest wall is obtained with this plate system, and no relapse occurs even after removal of the plate.

Alveolar bone remodeling in the early stage of experimental apical periodontitis in the rat mandible.

Apical periodontitis was surgically induced in the mandibular first molar of rats and chronological changes in the periapical bone tissue were observed by histochemistry and electron microscopy. On the second postoperative day (Day 2), tartrateresistant acid phosphatase (TRACPase)-positive cells emerged on the bone surface facing the inferior alveolar nerve, whereas alkaline phosphatase (ALPase)-positive cells proliferated on the bone marrow surface of the mandibular canal wall. On Day 3, the active resorption of the mandibular canal wall appeared on the surface facing the inferior alveolar nerve. The bone of the upper wall of the canal was completely resorbed. On Day 4, however, numerous ALPase-positive cells emerged over the bone surface facing the inferior alveolar nerve intermingled with TRACPase-positive cells. On Day 5, repair of the upper wall of the mandibular canal by new bone progressed. Bone formation was also observed on the bone surface facing the inferior alveolar nerve. On Day 6, the upper wall of the mandibular canal was remodeled by the new bone, whereas TRACPase-positive cells had already migrated over the bone surface in the vicinity of ALPase-positive cells. From Days 2 to 5, active trabecular bone formation continued in the bone marrow cavity close to the mandibular canal, while TRACPase-positive cells were found only on Day 6. These demonstrate that inflammatory stimuli activate bone formation coupled with bone resorption, as well as direct trabecular bone formation without a bone resorption phase. A rapid bone turnover in the early stage of apical periodontitis is also suggested. We conclude that bone defects in apical periodontitis are not the result of sole bone resorption but rather, active bone remodeling.

Reduced reperfusion injury in muscle. A comparison of the timing of EPC-K1 administration in rats.

EPC-K1, a phosphate diester of alpha-tocopherol and ascorbic acid, is a new hydroxyl radical scavenger. We examined the effects of EPC-K1 according to differences in the timing of its administration. Warm ischemia, produced by vascular pedicle clamping, was sustained for 4 hours. After 24 hours of reperfusion, muscle injury was evaluated in 4 groups: the first group received a sham operation, the second group was treated with an intravenous injection of EPC-K1 prior to ischemia, the third group was treated with EPC-K1 prior to reperfusion, and the fourth group was controls. Compared with the control group, both the preischemic and pre-reperfusion EPC-K1-treated groups showed a statistically significant amelioration in the reduction of isometric muscle contraction. There were also significant reductions in the muscle and serum levels of thiobarbituric acid reactive substances (TBA-RS) and muscle damage, indicated by the biochemical and histological study. A comparison of the timing of EPC-K1 administration revealed that only the muscle TBA-RS level in the pre-reperfusion EPC-K1-treated group was significantly higher than that in the preischemic EPC-K1-treated group. These observations indicate that EPC-K1 not only by preischemic but also by pre-reperfusion administration acted effectively on reperfusion injury in muscle, thereby improving muscle function.

Obturation of dentinal tubules with tannin-fluoride preparation (HY agent) incorporated into glass ionomer cement.

The degree of obturation of dentinal tubules as well as the dentinal uptake of F, Zn and Sr was investigated after placement of glass ionomer cement (GIC) containing variable proportions of the tannin-fluoride preparation, HY agent, into freshly prepared cavities. It was found that when HY agent was incorporated into the cement powder, there was both increase in electrical resistance in the dentinal floor of the GIC-restored cavity in addition to inhibition of dye penetration. Further, these changes were directly proportional to the concentration of HY agent. Electron probe microanalysis of the principal constituents of HY agent (F, Zn and Sr) revealed that the penetration depth for F and Zn was also directly proportional to the relative amount of incorporated HY agent, whereas Sr could not be detected regardless of HY concentration. Results clearly demonstrated that the higher the concentration of HY agent incorporated into GIC, the greater the degree of dentinal tubular obturation.