Effect of intensive interval training during unloading on muscle deoxygenation kinetics.

The present study investigated the effects of intensive interval training during 20-day of unloading on local muscle oxygenation kinetics evaluated by near infrared spectroscopy technique (NIRS). Eleven adult men completed 20-day unloading and were divided into two groups; the control (CON) group and training (TR) group. The TR group engaged in exercise training sessions that consisted of one-legged submaximal cycle exercise using the unloaded leg at 60 approximately 80% of VO(2peak) with intermittent rest periods, 25 min/day every other day. All subjects performed isometric knee extension exercise at 50% of their maximum voluntary contraction force before and after unloading. NIRS Delta[deoxy-Hb/Mb] signal was recorded from m. vastus lateralis and was fitted to an exponential equation in order to determine the kinetics parameters. The time constant (tau) of the % Delta[deoxy-Hb/Mb] was unchanged in the TR group, while it significantly increased in the CON group after unloading (pre, 5.0+/-1.0; post, 7.4+/-1.0 s). It is concluded that 20-day unloading increased the tau, suggesting deterioration of capacity for oxidative phosphorylation and oxygen utilization in a skeletal muscle. Additionally, the preservation of tau in the TR group suggested that intensive interval training could have an impact on the maintenance of muscle oxidative metabolism during unloading.

[Infectious endocarditis associated with multiple mycotic aneurysms; report of a case].

A 68-year-old man was referred to our hospital with infectious endocarditis (IE) of the mitral valve complicated by mycotic aneurysms located in the right middle cerebral artery (MCA) and the superior mesenteric artery (SMA). After coil embolization of the SMA aneurysm during angiography, surgical treatment of the MCA aneurysm was carried out. Antibiotic therapy for Enterococcus faecalis was continued throughout this period. After his IE was controlled, mitral valve repair was performed. The old vegetation on the edge of the anterior leaflet was resected and the defect was covered by transferring the posterior leaflet using the flip-over technique. Since there is no agreement about the optimum treatment of IE associated with multiple mycotic aneurysms, it is important to carefully plan the management of individual cases.

Differential activation in the medial temporal lobe during a sound-sequence discrimination task across age in human subjects.

To elucidate the brain mechanisms to encode sequential events, event-related potentials (ERPs) were recorded during a sound-sequence discrimination task using young and middle-aged adult subjects. In the task, a series of six or 12 kinds of natural sounds were sequentially presented; 70-80% of the stimuli were presented in a fixed order (Non-target), but the remaining stimuli, in a random order (Target). The subjects were instructed to detect the Targets and press a button at the end of each Target. In a control task, the same sounds were randomly presented (Control), and they were instructed to press the button at the end of each sound. Behavioral results indicated that the young subjects learned the task faster than did the middle-aged subjects. Positive ERP waves were evoked by Targets and Non-targets in the parieto-occipital area around 300-700 ms after stimulus onset. The mean amplitudes during this period in the young subjects were larger in Target than Control conditions, and those in Target condition were larger in the young than middle-aged subjects. Furthermore, the mean amplitudes in the Target condition were significantly correlated with behavioral performance. Equivalent dipoles for the ERPs evoked by Targets were estimated in the medial temporal lobe including the hippocampal formation and parahippocampal gyrus. The results suggest that the ERPs around 300-700 ms latency are involved in sound-sequence information processing. Furthermore, decrease in amplitudes of this positivity in the middle-aged subjects suggests that age-related memory decline is associated with deficits in encoding and retrieval of unfamiliar sequence.

Superior hepatic mitochondrial oxidation-reduction state in normothermic cardiopulmonary bypass.

OBJECTIVE: This study is the first comparative investigation of hepatic blood flow and oxygen metabolism during normothermic and hypothermic cardiopulmonary bypass. METHODS: Twenty-four patients undergoing coronary bypass operations were randomly divided into 2 groups according to their perfusion temperatures, either normothermia (36 degrees C) or hypothermia (30 degrees C). The clearance of indocyanine green was measured at 3 points. Arterial and hepatic venous ketone body ratios (an index of mitochondrial redox potential) and hepatic venous saturation were measured. RESULTS: Hepatic blood flow in both groups was identical before, during, and after cardiopulmonary bypass (normothermia, 499 +/- 111, 479 +/- 139, and 563 +/- 182 mL/min, respectively; hypothermia, 476 +/- 156, 491 +/- 147, and 560 +/- 202 mL/min, respectively). The hepatic venous saturation levels were significantly lower during cardiopulmonary bypass in the normothermic group (normothermia, 41% +/- 13%; hypothermia, 61% +/- 18%; P <.01), indicating a higher level of oxygen extraction use. The arterial ketone body ratio in the hypothermic group decreased severely after the onset of cardiopulmonary bypass (P <.01) and did not return to its subnormal value (>0.7) until the second postoperative day. However, the reduction in arterial ketone body ratio was less severe in the normothermic group. The difference in hepatic venous ketone body ratios was more obvious, and the hepatic venous ketone body ratios in the normothermic group were statistically superior to those of the hypothermic group throughout the course (P <.05-.01). CONCLUSIONS: Normothermic cardiopulmonary bypass provides adequate liver perfusion and results in a better hepatic mitochondrial redox potential than hypothermic cardiopulmonary bypass. Because arterial ketone body ratios reflect hepatic energy potential, normothermia was considered to be physiologically more advantageous for hepatic function.

Quasi-unit-cell model for an Al-Ni-Co ideal quasicrystal based on clusters with broken tenfold symmetry

We present new evidence supporting the quasi-unit-cell description of the Al72Ni20Co8 decagonal quasicrystal which shows that the solid is composed of repeating, overlapping decagonal cluster columns with broken tenfold symmetry. We propose an atomic model which gives a significantly improved fit to electron microscopy experiments compared to a previous proposal by us and to alternative proposals with tenfold symmetric clusters.

Deblocking and subsequent microsequence analysis of N alpha-blocked proteins electroblotted onto PVDF membrane.

A method was developed for direct microsequencing of N alpha-acetylated proteins electroblotted onto polyvinylidene difluoride membranes from polyacrylamide gels. N alpha-Acetylated proteins (greater than 32 pmol), including horse heart cytochrome c, five mutants of yeast cytochrome c, and bovine erythrocyte superoxide dismutase, were separated by SDS-PAGE and electroblotted onto polyvinylidene difluoride membranes. The portions of the membrane carrying the bands were cut out and treated with 0.5% polyvinylpyrrolidone in acetic acid solution at 37 degrees C for 30 min. The protein was digested on the membrane with 5-10 micrograms of trypsin at 37 degrees C for 24 h. During tryptic digestion, the resultant peptides were released from the membrane and the N-terminal peptide was efficiently deblocked with 50 mU of acylamino acid-releasing enzyme at 37 degrees C for 12 h. Picomole levels of the deblocked proteins could be sequenced directly by use of a gas-phase protein sequencer.

A mutant hemolysin with lower biological activity produced by a mutant Vibrio parahaemolyticus.

A mutant toxin (m-TDH) of thermostable direct hemolysin (Vp-TDH) of Vibrio parahaemolyticus was isolated from the culture of a strain of this organism mutagenized with N-methyl-N'-nitro-N-nitrosoguanidine. Although the m-TDH had a molecular structure similar to the native Vp-TDH, the m-TDH retained only about 7% residual hemolytic activity of the native toxin. Furthermore, other biological activities of m-TDH, such as lethality in mice and enterotoxicity in rabbit ileal loops, were also weakened. The m-TDH was immunologically indistinguishable from the native Vp-TDH. These results suggest that the m-TDH is only slightly different in structure from the native Vp-TDH. Also, the mutagenized site in m-TDH, which is not immunogenic, seems to be involved in expressing not only hemolytic activity but also lethal and enterotoxic activity.

Congenital mitral regurgitation from absence of the anterolateral papillary muscle.

A 21-year-old woman had congenital mitral regurgitation. Echocardiography showed absence of the anterolateral papillary muscle and corresponding marginal chordae. This rare abnormality was corrected by anterolateral commissural annuloplasty and insertion of artificial chordae to prevent prolapse of the anterior leaflet. Postoperatively, there was no regurgitation, and an appropriate mitral valve area was achieved.

Hemodynamic evaluation of 19-mm Carpentier-Edwards pericardial bioprosthesis in aortic position.

BACKGROUND: The aortic Carpentier-Edwards pericardial bioprosthesis offers good long-term clinical outcomes with a low rate of structural deterioration. However, little in vivo hemodynamic data is available for this bioprosthesis. METHODS: To determine the hemodynamic performance of the 19-mm Carpentier-Edwards pericardial valve, both cardiac catheterization and dobutamine stress echocardiography were electively performed in 10 patients. The mean age at the study was 71.6 +/- 4.4 years and the mean body surface area was 1.39 +/- 0.11 m2. The peak-to-peak gradient, instantaneous peak gradient, mean gradient, and valve orifice area were measured by standard cardiac catheterization. The Doppler-derived gradients and valve orifice area were also measured both at rest and during dobutamine infusion. RESULTS: The average peak-to-peak gradient, instantaneous peak gradient, mean gradient, and valve orifice area measured by catheterization were 13.0 +/- 5.4 mmHg, 28.5 +/- 7.7 mmHg, 12.0 +/- 4.9 mmHg, and 1.55 +/- 0.45 cm2, respectively. The peak and mean Doppler gradients, and valve orifice area by resting echocardiography were 27.7 +/- 9.5 mmHg, 12.3 +/- 4.8 mmHg, and 1.39 +/- 0.26 cm2, respectively. At a dosage of 10 microg/kg/min of dobutamine, the mean Doppler gradient rose mildly to 22.2 +/- 4.8 mmHg, while the cardiac output increased from 4.49 +/- 0.44 to 6.64 +/- 0.87 L/min. The valve orifice area during the 10 microg/kg/min dobutamine infusion (1.55 +/- 0.25 cm2) was significantly larger than its value at rest (p < 0.05). CONCLUSIONS: With acceptable hemodynamic performance, use of the aortic 19-mm Carpentier-Edwards pericardial valve is a reliable option for elderly patients with a small annulus.

The structure of a decagonal Al72Ni20Co8 quasicrystal.

The structure of a decagonal Al72Ni20Co8 quasicrystal with space group P10(5)/mmc has been determined on the basis of a single-crystal X-ray data set using the five-dimensional description. The best-fit model structure based on a cluster model having lower symmetry than the decagonal symmetry with 103 parameters gives wR = 0.045 and R = 0.063 for 449 reflections. The structure is well described by the hexagon, boat and star tiling with an edge length of 6.36 A and is very consistent with recent high-resolution electron-microscopy images. The refined structure is compared with previously discussed model structures including cluster-based models having 20 A tenfold symmetric clusters.

CT and histological findings of diffuse lipomatosis with a hemangioendothelioma: a case report.

A 3 1/2-year-old boy with multiple soft tissue tumors and weakness of the right lower extremity is presented. Swelling of the right lower extremity was noted at 3 weeks, and soft masses at the hip at one year and in the inguinal region at 2 1/2 years of age. Right lower extremity weakness was noted about one year and non-progressive. CT scanning demonstrated characteristic subcutaneous lipomatosis with muscle involvement and a pelvic mass with positive enhancement that infiltrated into the spinal canal. Histological examination revealed diffuse lipomatosis involving muscles in the right hip mass and a lipoma with a hemangioendothelioma in the right inguinal mass. Diffuse lipomatosis combined with a lipoma and a hemangioendothelioma suggests a hamartomatous origin.

The syndrome of the absence of a septum pellucidum with porencephaly.

Two cases of a complex brain malformation including the absence of a septum pellucidum and bilateral porencephaly were reported and compared with Aicardi's cases. The two cases have congenital hemiplegia or double hemiplegia and mental retardation, and one of them has optic atrophy. CT scans revealed the absence of a septum pellucidum and a specific position and shape of the clefts. The syndrome of the absence of a septum pellucidum and porencephaly may represent a specific type of true porencephaly, and the cause must occur before 16 weeks of gestation.

A rare case of Aicardi syndrome with severe brain malformation and hepatoblastoma.

A 2-month-old Japanese girl exhibited tonic seizure, agenesis of the corpus callosum, lacunar chorioretinopathy, vertebral anomalies, electroencephalographic abnormalities and a malignant tumor. Autopsy revealed a hepatoblastoma and severe brain malformations consisting of callosal agenesis, arhinencephaly, marked polymicrogyria and optic nerve anomalies. It was thought that the pathogenic factor in this case may exert its effect during the fourth or fifth week of intrauterine life, and then may continue until the beginning of neuronal migration (about 3 months). This is the first reported case of Aicardi syndrome associated with hepatoblastoma, and may provide a link between teratogenicity and oncogenicity.

Multimodality evoked potentials in progression of metachromatic leukodystrophy.

A 2-yr-3-mo-old girl with metachromatic leukodystrophy (MLD) was examined using serial multiple electrophysiological procedures. Sensory nerve conduction velocity was delayed earlier and more severely than motor nerve conduction velocity. Visual evoked potentials (VEPs) showed prolonged latency of wave IV. Auditory brainstem responses (ABRs) showed prolonged latency of waves I and V, and the I-V interval. As to the interpeak latency of somatosensory evoked potentials (SEPs), the P9-P14 and the P14-N20 intervals were prolonged on admission. Two months later, both intervals were more prolonged, but the prolongation of the P9-P14 interval was the most prominent. The demyelination in our case may have started in the cerebral white matter, progressed to the peripheral nerves, and at last via the spinal root reached the brainstem. An electrophysiological follow-up study may be valuable in the understanding of the progressive pathological changes and in the evaluation of therapeutic measures.

Clinical, biochemical and ultrastructural study on the pathogenesis of hyperornithinemia-hyperammonemia-homocitrullinuria syndrome.

A 10-year-old boy with the hyperornithinemia, hyperammonemia and homocitrullinuria (HHH) syndrome is described. With dietary restriction of protein intake and supplementary administration of L-ornithine and L-arginine, the high concentration of ammonia decreased and the clinical signs of truncal ataxia and lethargy improved. A deficiency of ornithine transport into liver mitochondria was demonstrated biochemically, and glycogen granules and smooth surface endoplasmic reticulum were increased, but mitochondria showed normal construction ultrastructurally. Cranial computed tomography (CT) showed diffuse white matter low density and cerebellar vermis atrophy. The impairment of ornithine transport and energy production in the central nervous system may be related to the cranial CT findings and neurological signs.

The influence of age and depth of dentin on bonding.

OBJECTIVES: The purpose of this study was to investigate what influence the two variables of dentin depth and age may have on the tensile bond strengths of three bonding systems. METHODS: Dentin discs prepared from human molars were divided into young and old, superficial and deep surfaces. Three bonding systems, Scotchbond Multi-purpose (3M Dental Products), Superbond D-liner (Sun Medical Co.), and Liner Bond II (Kuraray Co.) were the materials tested for tensile bond strength. In addition, the structural variation of the resin-impregnated, or hybrid, layer was compared among the two variables and three bonding systems. RESULTS: Tensile bond strengths exceeding 10 MPa were obtained for all materials. After ANOVA, an effect on tensile bond strength could be attributed to dentin age or depth for only Superbond D-liner used on deep-young dentin as compared with old-superficial dentin. All other group comparisons failed to show any variation between dentin depth or age. However, specimens bonded to deeper dentin showed slightly lower strengths. SEM observations showed thicker resin-impregnated layers for Scotchbond MP and Superbond D-liner compared with Liner Bond II. Liner Bond II exhibited a thinner and more diffuse resin-impregnated layer, believed to be due to the different dentin conditioning method. SIGNIFICANCE: Dentin age or depth may not show as great an influence on bond strengths with the newer type of bonding systems. The resin-impregnated layer quality, rather than thickness, is believed to be the most important factor for obtaining high tensile bond strengths.

Real time measurement of heparin concentration during cardiopulmonary bypass.

BACKGROUND: A heparin/protamine titration system for measurement of heparin levels (Hepcon) is promising for efficient anticoagulation during cardiopulmonary bypass (CPB). METHODS: Fifty-seven patients subjected to CPB were divided into two groups, control (n = 24) and Hepcon groups (n = 33). The Hepcon group was further divided into three subgroups according to perfusion temperature. For the control group, conventional administration of an anticoagulant (300 IU/kg of heparin) and reversal protocol (heparin 1: protamine 1) was performed. For the Hepcon group, a heparin dose-response assay directed the initial dose of heparin. Hepcon also determined the dose of protamine by the titration. The initial dose of heparin in the control group (300 IU/kg) was statistically less than that of Hepcon group (360+/-80 IU/kg). RESULTS: In the Hepcon group, the sensitivity to heparin was correlated with coagulation time (r = -0.78) and antithrombin III levels (r = 0.70), and individual difference of sensitivity resulted in a wide range of dosage (160 to 490 IU/kg). A strong correlation was observed between plasma and whole blood concentration of heparin (r = 0.86). However, they did not correlate with ACT values. Perfusion temperature didn't affect the heparin level, but did the ACT value. In the Hepcon group, the dose of protamine was significantly less and adverse events were rare. CONCLUSIONS: In conclusion, whole blood heparin measurements correlated well with plasma heparin concentration. Protamine titration of heparin reduced the dose of protamine and decreased the chance of adverse reactions.

Beneficial effect of balloon-induced pulsatility on brain oxygenation in hypothermic cardiopulmonary bypass.

BACKGROUND: Sufficient O2 delivery to meet the demand is an important factor for protecting the brain during cardiopulmonary bypass (CPB). This study was designed to investigate the influences of temperature, pulsatility of blood flow (intra-aortic balloon pump-induced) and flow rate during CPB on the cerebral oxygenation. METHODS: Patients were divided into five groups. Normothermia (36 degrees C): pulsatile (n=8, 2.5 L/min/m2), nonpulsatile (n=12, 2.5 L), and nonpulsatile perfusion (n=12, 2.8 L); hypothermia (30 degrees C): pulsatile (n=9, 2.5 L) and nonpulsatile perfusion (n=11, 2.5 L). The oxygen saturation (SjVO2), lactate and CPK-BB levels in the jugular venous blood were measured. RESULTS: In all of the normothermic groups, the SjVO2 value decreased during the CPB (p<0.1-0.01). No remarkable change was observed in the hypothermic groups, with the exception during the rewarming period in the nonpulsatile group. A higher SjVO2 and a lower frequency of SjVO2 values <50% were observed in the hypothermic pulsatile group, as compared with those in the normothermic groups (p<0.05). The levels of CPK-BB were nearly the same, however the levels of lactate were higher in the normothermic pulsatile and nonpulsatile (2.5 L) groups (p<0.05). CONCLUSIONS: We concluded that the hypothermic CPB was advantageous over normothermic CPB in regard to the SjVO2 levels and lactate production. The beneficial effect of intra-aortic balloon pump assist was only obtained in the hypothermic CPB.