Development of Network Plug-in Actuator

We propose an intelligent connector (ICN) that uses a network plug-in actuator (NPA) or an intelligent connector (ICN) to reduce the number of signal and power cables and integrates an AC servomotor and motor drive with serial signal wires using a controller area Network (CAN). The ICN connects the NPA and a controller such as a personal computer and connects different networks such as the Ethernet, CAN, IEEE1394, or USB. We developed an NPA series from 5 W to 750 W and verified their functions. We also evaluated the ICN performance using the NPA. This system was installed on an “econovehicle” and its effectiveness was successfully demonstrated.

Progressive wild-type transthyretin deposition after liver transplantation preferentially occurs onto myocardium in FAP patients

To elucidate whether progressive wild-type transthyretin (TTR) deposition can actually occur after liver transplantation (LT), amyloid fibrils were investigated in two familial amyloid polyneuropathy patients with TTR Val30Leu variant, who died 1 year after LT. Amyloid fibrils were extracted from cardiac muscles, sciatic nerves and kidney, which were investigated by the immunoprecipitation-mass spectrometry method and liquid chromatography-ion trap mass spectrometry analysis. The ratio of wild-type to variant TTR in cardiac muscle was approximately 5:5 before LT, but greatly increased to about 9:1 after transplantation. The ratios in sciatic nerves and kidney obtained at autopsy were approximately 5:5. Wild-type TTR was undetectable in kidney amyloid obtained before LT. Our results indicate that paradoxical wild-type TTR deposition after LT can preferentially occur in myocardium, leading to fatal cardiac dysfunction, but it is quite likely that this phenomenon can also occur in other visceral organs.

Effect of VEGF receptor antagonist (VGA1155) on brain edema in the rat cold injury model

Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis and a strong vascular permeability factor. Blockade of VEGF may have a potential to treat brain edema after brain injury. In the rat cold injury model, the VEGF receptor antagonist VGA1155 significantly reduced the brain water content and the maximum effect was obtained when given at 30 minutes after injury. This effect was in dose-dependent manner and the dose of 25 mg/kg showed the maximum effect. With this dose, VGA1155 also significantly reduced vascular permeability. Histological evaluation of brain lesion showed no significant reduction of damaged area 1 week after injury by VGA1155. The data suggest that VGA1155 may have antiedematous effect in acute phase after cold injury.

In vivo X-ray angiography in the mouse brain using synchrotron radiation

BACKGROUND AND PURPOSE

We, for the first time, performed in vivo x-ray angiography in the mouse brain using SPring-8, a third-generation synchrotron radiation facility.

METHODS

A thin PE-50 tube was placed in the unilateral external carotid artery in adult male C57BL/6J mice. While maintaining the blood flow in the internal carotid artery, 33 muL of contrast agent was injected and then selective angiography of the hemisphere was performed.

RESULTS

The average diameters of cerebral artery were as follows: 142.5+/-7.90 microm in middle cerebral artery, 138.3+/-9.35 microm in anterior cerebral artery, 120.5+/-5.53 microm in posterior cerebral artery, and 162.6+/-10.87 microm in internal carotid artery (n=5). To demonstrate the changes in diameter, we induced hypercapnia and detected the dilatation of the vessels between 121% and 124% of the original diameters (n=5). We also repeated angiography in the mice before and after intracarotid injection of vasodilatation drugs papaverine hydrochloride, ATP disodium, and fasudil hydrochloride hydrate and demonstrated the chronological changes in the diameters in each artery at 1, 5, 15, and 30 minutes after injection (n=1 for each drug).

CONCLUSIONS

Using only a minimum volume of the contrast agent, synchrotron radiation enables us to study x-ray angiography in the mouse brain. The morphology of the vessels can be clearly observed under physiological conditions. The diameters and their changes can also be successfully studied in vivo.

Carotid artery occlusion and collateral circulation in C57Black/6J mice detected by synchrotron radiation microangiography

Using monochromatic synchrotron radiation, we performed microangiography in C57BL/6J mice and investigated their vasculature after unilateral and bilateral carotid artery occlusion. Bilateral occlusion of the carotid artery was made by a ligation of the left common carotid artery followed by a ligation of the right internal carotid artery (ICA) two days later (n=12). Five days after the second surgery, angiography was performed. Unilateral occlusion was made by clipping the right ICA and then angiography was performed immediately (n=5). The control mice did not undergo any occlusion (n=5). We removed the brain of the bilateral occlusion mice after angiography and examined the infarction area. The cerebral microvessels in all animals were clearly visualized. In the control mice, the posterior communicating artery (Pcom) was not visualized. In the unilateral occlusion mice, the anastomosis of the pterygopalatine artery (PPA) and the external carotid artery (ECA) were recognized. The PPA is thus considered to play a role in the collateral vessel between the ICA and the ECA. The Pcom was not visualized. In the bilateral occlusion mice, the Pcom was observed either unilaterally (n=5) or bilaterally (n=5). The Pcom supplied blood flow to the anterior circulation from the vertebrobasilar arteries. The bilateral occlusion mice that had at least one visualized Pcom did not have any infarction. We could successfully visualize the cerebral vasculature of normal mice and carotid artery occluded mice in an in vivo study. Microangiography can demonstrate the development of vasculature and the blood flow dynamics in mice.

Pathological Result of Basilar Artery Stenosis Rapidly Progressed and Ruptured with Stent-Assisted Angioplasty

Intracranial artery angioplasty utilizing coronary stent is now widely tried as an effective alternative for treating intracranial artery stenosis, and several successful result of stent-assisted angioplasty for intracranial artery were reported.

Authors experienced a case of the basilar artery stenosis, in which re-stenosis progressed rapidly after simple balloon angioplasty and resulted in vessel rupture during stent-assisted angioplasty. Pathological result achieved by autopsy showed vessel wall disruption at the stent and multiple interruptions and defect of elastic laminar.

Neurotrophic effect of hepatocyte growth factor on neonatal facial motor neurons

The neurotrophic effect of hepatocyte growth factor (HGF) on axotomized facial motor neurons was examined after local application of HGF to the proximal facial nerve stump of the neonatal rat on post-natal day one (P1). Motor neuron survival was expressed as the neuronal cell count on the injured side as a percentage of that on the noninjured side. Motor neuron survival of the control group was 76% on P3, 54% on P5 and 23% on P8, that of the HGF-treated group 78% on P3, 69% on P5 and 31% on P8, and that of the brain-derived neurotrophic factor (BDNF)-treated group 91% on P5 and 45% on P8. The motor neuron survival rates were then adjusted by deducting the facial motor neurons corresponding to the uninjured retroauricular branch (20%) of the facial nerve. The adjusted values were 70% (P3), 42% (P5) and 4% (P8) for the control group, 72% (P3), 61% (P5) and 14% (P8) for the HGF-treated group, and 88% (P5) and 32% (P8) for the BDNF-treated group. These findings demonstrate that HGF has a neuroprotective effect on injured facial motor neurons and suggest that HGF has neurotrophic properties distinct from those of BDNF.

Thickness of the roof of the glenoid fossa and condylar bone change: a CT study

OBJECTIVES

The aim of this study is to investigate the relationship between the thickness of the roof of the glenoid fossa in the temporomandibular joint (TMJ) and the existence and types of condylar bone change.

MATERIALS AND METHODS

Helical CT was used to measure the thickness of the roof of the glenoid fossa at its thinnest part in 37 orthodontic patients with temporomandibular disorders. Condylar bone changes were classified into four types: no bone change (24 joints); flattening (19 joints); osteophyte formation (13 joints); and erosion (18 joints).

RESULTS

The roof of the glenoid fossa was significantly thicker in joints with bone change than in joints with no bone change (Mann-Whitney U-test, P<0.05). There was also a significant difference in relation to the type of condylar bone change: the thickness of the roof of the glenoid fossa in the erosion group was significantly greater than in the no bone change (P<0.01), flattening (P<0.05) and osteophyte formation (P<0.05) groups (Kruskal-Wallis and Games-Howell tests).

CONCLUSION

Compensative bone formation in the roof of the glenoid fossa might help to withstand the increased stress in the TMJ accompanying condylar bone change, especially erosion.

Regenerative process of the facial nerve: rate of regeneration of fibers and their bifurcations

After the main trunk of the mouse facial nerve was injured by crushing, a fiber tracing method was used to quantify the facial motor neurons that extended regenerating nerve fibers to the specific site of the facial nerve branch. The total number of motor neurons retrogradely labeled with a fluorescent tracer, Fluoro-Gold (FG), were 0 on postsurgical days (PSDs) 1 and 2, 75+/-25 on PSD3, 264+/-21 on PSD4, 378+/-19 on PSD6, 428+/-19 on PSD8, 491+/-13 on PSD12 and 532+/-15 on PSD16. Assuming that the FG-positive neurons (535+/-11) of the control mice represent 100%, the FG-labeled neurons accounted for 0, 14, 49, 71, 80, 92 and 99% on the corresponding days. Two different fluorescent tracers were applied to the different facial nerve branches 16 days after facial nerve injuries. Double-labeled neurons were consistently found in the nerve-crushed facial nucleus (3.2%), and their number increased in the nerve-transected facial nucleus (12.2%). The present study indicates that the regenerating facial nerve consists of heterogeneous nerve fibers with varying growth rates and that excessive axonal branching occurs more frequently in the nerve-transected than in the nerve-crushed injuries.

Expanded polytetrafluoroethylene membrane for prevention of adhesions in patients undergoing external decompression and subsequent cranioplasty

Cranioplasty performed after external decompression for brain swelling may be difficult because of the development of adhesions between the temporal muscle and the dura. Membranes composed of expanded polytetrafluoroethylene (ePTFE) were inserted at external decompression to prevent such adhesions. The ePTFE membranes were placed suturelessly between the temporal muscle and the dura, covering the proximal portion of the temporal muscle at the sphenoidal ridge and the dural suture line. In addition, part of the membrane was placed directly below the skin incision to allow easy visualization at subsequent cranioplasty in 10 patients. Cranioplasty was performed 38 to 126 days (mean 63.9 days) after external decompression. No adhesions were observed, either between the ePTFE membranes and the dura, or between the membranes and the temporal muscle. No temporal muscle and dural injuries occurred during cranioplasty, and no patient showed signs of infection. Mean operating time was 71.0 minutes and mean blood loss was 75.2 ml. Sutureless insertion of ePTFE membranes at external decompression increases the ease and safety of subsequent cranioplasty, decreases operating time and blood loss, and avoids injury to the temporal muscle and dura.

Great potentiality of neonatal facial motor neurons for neural plasticity as determined by functionally essential neuronal population

The present study was undertaken to determine the neuronal population essential for normal and minimal facial function of young adult rats that had received various degrees of crush injuries to the facial nerve in the neonatal period. Using a neuronal tracer, it was found in young adult rats receiving neonatal injuries that the minimum number of tracer-labeled facial motor neurons necessary for normal facial function corresponded to 13-14% of the neurons (2540+/-64) of the age-matched control animals, whereas the minimum number of neurons necessary for minimal facial function corresponded to 5%. On the other hand, the minimum numbers of tracer-labeled facial motor neurons necessary for normal and minimal facial function of young adult rats that received various degrees of crush injuries corresponded to 61 and 27-30%, respectively, of the neurons (2540+/-64) of the uninjured control animals. These results indicate that the facial function of animals with nerves crushed at the neonatal stage can be adequately maintained by a very small population of neurons, implying a great potential of neonatal neurons for neural plasticity.

Functionally essential neuronal population of the facial motor nucleus

Cranial nerve impairment is one of the more serious complications in neurosurgery. Nevertheless, the important question of how many neurons are required for cranial nerve functions remains unanswered. The VIIth cranial nerve (facial nerve) in mice was subjected to graded crush injuries. After assessment of the facial function, the number of uninjured, healthy facial motor neurons was quantified with a retrograde neuronal tracer. We report that normal facial function is preserved if intact neurons account for more than 56% of the control value, while complete facial paralysis occurs if intact neurons are reduced to less than 32% of the control value.

Direct surgical removal of the dural arteriovenous fistulas involving transverse-sigmoid sinuses

We investigated the operative methods and the angiographical classification in eight patients with dural arteriovenous fistulas involving transverse-sigmoid sinuses. There were two men and six women with a mean age of 68.3 (range 61-73) years. The initial symptoms were focal neurological deficits (aphasia, hemiparesis, hemianopsia) because of intracranial haematoma in four patients, dementia in two, headache in one and pulsatile tinnitus in one. Preoperatively, transarterial coil embolisaton was performed in four patients and transvenous coil embolisation in three. Finally total removal was performed in all patients. In all patients angiogram showed the presence of sinus occlusion diagnosed in the late venous phase and retrograde flow from the sinuses to the cortical veins. According to Borden's classification, three patients were classified as Type II-C (or C'), four patients as Type III-D and one patient as Type E. The volume of blood loss did not change either with or without preoperative transarterial coil embolisation. There was no new procedure-related morbidity. The presence of sinus occlusion diagnosed in the late venous phase and retrograde flow from the sinuses to the cortical veins indicate that total removal is possible.

Periosteal osteosarcoma of the mandible

We report a rare case of periosteal osteosarcoma of the mandible in a 15-year-old girl. Extension of the tumour into the bone marrow by way of the periodontal ligament is demonstrated.

Inhibitory effects of anthraquinones and bianthraquinones on Epstein-Barr virus activation

Short-term in vitro assays for anti-tumor promoters were carried out for several anthraquinones and bianthraquinones, which were isolated from Cassia siamea and derived from cascaroside A. Anthraquinone monomers showed higher anti-tumor promoting activity than that of bianthraquinones.

Correlation with redox potentials and inhibitory effects on Epstein-Barr virus activation of azaanthraquinones

The redox potentials have been determined for nine azaanthraquinones in phosphate buffer at pH 7.2 by means of cyclic voltammetry. A definite correlation has been found between the redox potentials and the inhibitory effects of the azaanthraquinones on Epstein-Barr virus early antigen (EBV-EA) activation. It has further been shown that the correlation can be made better by introducing an electronic property, i.e., the atomic charge at O11 as an additional parameter.

Influence of organic solvents on the growth of marine microalgae

Ninety-six-hour toxicity tests of five organic solvents (methanol, ethanol, acetone, N,N-dimethylformamide [DMF], and dimethyl sulfoxide [DMSO]) on nine species of marine microalgae (Bacillariophyceae; Skeletonema costatum, and Chaetoceros calcitrans, Prasinophyceae; Tetraselmis tetrathele, Haptophyceae; Isochrysis galbana and Pavlova lutheri, Dinophyceae; Prorocentrum minimum, Raphidophyceae; Heterosigma akashiwo, Euglenophyceae; Eutreptiella sp., Chlorophyceae; Dunaliella tertiolecta) were conducted. For D. tertiolecta, T. tetrathele, I. galbana, and P. lutheri, methanol was the least toxic solvent. For S. costatum, C. calcitrans and Eutreptiella sp., DMSO was the least toxic solvent. For Heterosigma akashiwo, DMF was the least toxic solvent. In general, solvent toxicity was ethanol > methanol or acetone > DMF > DMSO. In relation to sensitivity of the microalgae to solvents, D. tertiolecta and T. tetrathele were lower in sensitivity, and Eutreptiella sp. and H. akashiwo were higher in sensitivity than the other species. The no observed effect concentration (NOEC) of acetone, DMF, and DMSO were higher than for ethanol and methanol. Acetone, DMF, and DMSO were suitable for carrier solvents used in toxicity test of water-insoluble chemicals. Excellent regression between logEC(50) and logNOEC was obtained (logNOEC = 1.09 x logEC(50) - 0.84, R(2) = 0.91). This equation indicated that higher toxicity was higher application factor (EC(50)/NOEC) than lower toxicity. All application factors were higher than 0.1.

Cerebral vasoreactivity and internal carotid artery flow help to identify patients at risk for hyperperfusion after carotid endarterectomy

BACKGROUND AND PURPOSE

Hyperperfusion syndrome is a rare but potentially devastating complication after carotid endarterectomy (CEA). The aim of this study was to investigate whether preoperative measurement of cerebral vasoreactivity (CVR) and intraoperative measurement of internal carotid artery (ICA) flow could identify patients at risk for hyperperfusion after CEA.

METHODS

For 26 patients with unilateral ICA stenosis >/=70%, cerebral blood flow (CBF) and CVR were investigated before and 1 month after CEA, with resting and acetazolamide-challenge single-photon emission CT. CBF on the first postoperative day was also measured. ICA flow was measured before and after reconstruction by electromagnetic flowmeter during surgery.

RESULTS

Ipsilateral CBF on the first postoperative day significantly increased relatively (56.6+/-53.2%) as well as absolutely (37.9+/-8.8 to 57.7+/-18.0 mL/100 g per minute) in the reduced CVR group (CVR <12%) but not in the normal CVR group (CVR >/=12%) (10.3+/-15.5% and 40.6+/-7.9 to 43.9+/-5.7 mL/100 g per minute, respectively). One month later, this difference almost disappeared. Two patients showed ipsilateral CBF increase of >/=100%. A significant association of intracerebral steal with hyperperfusion (CBF increase >/=100%) on the first postoperative day was also observed. ICA flow increase after reconstruction significantly correlated with CBF increase on the first postoperative day in the reduced CVR group but not in the normal CVR group. The threshold of ICA flow increase for hyperperfusion was estimated to be 330 mL/min in the reduced CVR group.

CONCLUSIONS

Single-photon emission CT with acetazolamide challenge and ICA flow measurement during surgery could identify patients at risk for hyperperfusion after CEA, in whom careful monitoring and control of blood pressure should be initiated even intraoperatively.

Microvolt T wave alternans in human cardiac hypertrophy: electrical instability and abnormal myocardial arrangement

INTRODUCTION

Although T wave alternans (TWA) is a promising risk marker for myocardial electrical instability, it remains unclear how the presence of TWA is related to myocardial damage.

METHODS AND RESULTS

TWA was measured in 28 patients with hypertrophic cardiomyopathy (HCM), 29 patients with hypertensive left ventricular hypertrophy (HLVH), and 15 normal volunteers using a CH2000 system. The amplitude of TWA (Valt) was measured at the lead with the maximum amplitude. Cardiac biopsy was performed in 12 HCM patients, who were divided into two groups (severe and mild) based on histologic findings of myocardial disarray and fibrosis. TWA was positive (Valt > 1.9 microV) in 61% of HCM and 31% of HLVH, despite a nearly identical left ventricular mass index (176 +/- 65 g/m2 vs 175 +/- 39 g/m2). Valt at heart rate = 110 beats/min was significantly greater in HCM with severe disarray and fibrosis than in HCM with mild disarray and in HLVH.

CONCLUSION

In HCM patients, a positive TWA test probably is related to abnormal myocardial arrangement (disarray) and/or fibrosis, and it may reflect electrical instability of the myocardium.