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When we consider a large number of substreams and constellations in channel-coded space division multiplexing (SDM) in a MIMO channel, computational complexity of a soft MIMO decoder based on the maximum likelihood (ML) detection becomes enormous. Even in complexity-reduced processing such as sphere decoding, the MIMO detector must search several non-ML points to calculate a log-likelihood ratio (LLR) of each bit for a soft-input channel decoder. In the paper, we propose a simplified iterative processing method for the soft MIMO detector and soft-input/soft-output (SISO) channel decoder to decrease the number of Euclidean distance calculations of non-ML points. To update the non-ML points to be searched, we monitor the LLR value of each bit returned from the SISO channel decoder. The computer simulation assuming 4tx-4rx turbo-coded SDM of 16-QAM shows that the proposed method provides the gain of 0.7 dB at FER of 0.01 against the non-iterative method using 65536 points, where the number of searched points per iteration at average E/sub b//N/sub 0/ = 1 dB was 17.8 in average and 624 at most in the proposed method.

In multiple-input multiple-output (MIMO) systems, eigenbeam space division multiplexing (E-SDM) has a higher performance compared to conventional SDM and has an advantage that simple detection algorithms are available at a receiver. However, the transmitter requires MIMO channel information. If it has an error, the performance degradation is inevitable. In this paper, we propose a compensation way against channel information error due to temporal channel transition. The effect is also numerically analyzed.

Based on the indoor measurement campaign, the performance of MIMO spatial multiplexing in the LOS environments has been compared with that in the NLOS ones. It has been shown that the average BER performance in the LOS environments is better than that in the NLOS ones despite higher fading correlations. The BER is obtained by computer simulations using MIMO channel measurements. We compare the performance with the one in NLOS environments. Furthermore, we investigate the BER performance of an eigenbeam-space division multiplexing (E-SDM) system where the channel state information is known also at the TX end.

An OFDM technique has been utilized for wireless local area networks (WLANs). Spatial division multiplexing using a multiple-input multiple-output (MIMO) technique has been studied to increase the transmission rate to over 100 Mbps. Before we can detect the transmitted data, we need AGC adjustment, timing synchronization, frequency offset estimation, and channel estimation using a preamble. The current WLAN system with a single transmit antenna, based on the IEEE 802.11a standard, uses a four OFDM symbol duration preamble. However, the preamble period proposed so far for the MIMO-OFDM system grows linearly with the transmit antenna number. This results in an increased overhead, and the conventional technique is not efficient. In this paper, we present a channel and frequency offset estimation scheme using a preamble with four OFDM symbol duration for the MIMO-OFDM system in WLANs. This preamble has the same duration as that of the IEEE 802.11a standard, and does not increase the overhead. Computer simulation results are provided to demonstrate the performance of the proposed scheme.

Membrane current was recorded from neurons in rabbit vesical parasympathetic ganglia, utilizing single electrode voltage clamp techniques. ATP (0.1–1 mM) caused an inward current (IATp) associated with an increased conductance at a holding potential of −50 mV. ADP (0.1–1 mM) and 5′-O-3-thiotriphosphate (0.1–0.6 mM) but not AMP (0.3–2 mM) and adenosine (0.1–2 mM) mimicked the actions of ATP. The IATp reversed its polarity at −12.1 ± 1.4 mV. The amplitude of the IATp was depressed in low sodium solutions and in nominally calcium-free solutions but not in low chloride solutions. Suramin (10–100 μM) and reactive blue 2 (10–100 μM), P2-antagonists, reversibly depressed the IATp. In contrast, hexamethonium (100 μM) did not affect the IATp. These data suggest that ATP activates cation channels through P2X receptor subtypes in rabbit parasympathetic neurons.

Pneumonectomized rats injected with the alkaloid toxin, monocrotaline, develop progressive neointimal pulmonary vascular obliteration and pulmonary hypertension resulting in right ventricular failure and death. The antiproliferative immunosuppressant, triptolide, attenuates neointimal formation and pulmonary hypertension in this disease model (Faul JL, Nishimura T, Berry GJ, Benson GV, Pearl RG, and Kao PN. Am J Respir Crit Care Med 162: 2252–2258, 2000). Pneumonectomized rats, injected with monocrotaline on day 7, were killed at days 14, 21, 28, and 35 for measurements of physiology and gene expression patterns. These data were compared with pneumonectomized, monocrotaline-injected animals that received triptolide from day 5 to day 35. The hypothesis was tested that a group of functionally related genes would be significantly coexpressed during the development of disease and downregulated in response to treatment. Transcriptional analysis using total lung RNA was performed on replicate animals for each experimental time point with exploratory data analysis followed by statistical significance analysis. Marked, statistically significant increases in proteases (particularly derived from mast cells) were noted that parallel the development of vascular obliteration and pulmonary hypertension. Mast-cell-derived proteases may play a role in regulating the development of neointimal pulmonary vascular occlusion and pulmonary hypertension in response to injury.

The latent plasma carboxypeptidase thrombin-activable fibrinolysis inhibitor (TAFI) is activated by thrombin/thrombomodulin on the endothelial cell surface, and functions in dampening fibrinolysis. In this study, we examined the effect of activated TAFI (TAFIa) in modulating the proinflammatory functions of bradykinin, complement C5a, and thrombin-cleaved osteopontin. Hydrolysis of bradykinin and C5a and thrombin-cleaved osteopontin peptides by TAFIa was as efficient as that of plasmin-cleaved fibrin peptides, indicating that these are also good substrates for TAFIa. Plasma carboxypeptidase N, generally regarded as the physiological regulator of kinins, was much less efficient than TAFIa. TAFIa abrogated C5a-induced neutrophil activation in vitro. Jurkat cell adhesion to osteopontin was markedly enhanced by thrombin cleavage of osteopontin. This was abolished by TAFIa treatment due to the removal of the C-terminal Arg168 by TAFIa from the exposed SVVYGLR alpha 4 beta 1 integrin-binding site in thrombin-cleaved osteopontin. Thus, thrombin cleavage of osteopontin followed by TAFIa treatment may sequentially up- and down-modulate the pro-inflammatory properties of osteopontin. An engineered anticoagulant thrombin, E229K, was able to activate endogenous plasma TAFI in mice, and E229K thrombin infusion effectively blocked bradykinin-induced hypotension in wild-type, but not in TAFI-deficient, mice in vivo. Our data suggest that TAFIa may have a broad anti-inflammatory role, and its function is not restricted to fibrinolysis.

Background— Pulmonary vascular injury by toxins can induce neointimal formation, pulmonary arterial hypertension (PAH), right ventricular failure, and death. We showed previously that simvastatin attenuates smooth muscle neointimal proliferation and pulmonary hypertension in pneumonectomized rats injected with the alkaloid toxin monocrotaline. The present study was undertaken to investigate the efficacy of simvastatin and its mechanism of reversing established neointimal vascular occlusion and pulmonary hypertension. Methods and Results— Pneumonectomized rats injected with monocrotaline at 4 weeks demonstrated severe PAH at 11 weeks (mean pulmonary artery pressure [mPAP]=42 versus 17 mm Hg in normal rats) and death by 15 weeks. When rats with severe PAH received simvastatin (2 mg · kg −1 · d −1 by gavage) from week 11, there was 100% survival and reversal of PAH after 2 weeks (mPAP=36 mm Hg) and 6 weeks (mPAP=24 mm Hg) of therapy. Simvastatin treatment reduced right ventricular hypertrophy and reduced proliferation and increased apoptosis of pathological smooth muscle cells in the neointima and medial walls of pulmonary arteries. Longitudinal transcriptional profiling revealed that simvastatin downregulated the inflammatory genes fos, jun, and tumor necrosis factor-α and upregulated the cell cycle inhibitor p27Kip1, endothelial nitric oxide synthase, and bone morphogenetic protein receptor type 1a. Conclusions— Simvastatin reverses pulmonary arterial neointimal formation and PAH after toxic injury.

In this paper, we propose a novel downlink null-forming technique for space division multiple access (SDMA) in a multiple-input multiple-output (MIMO) channel where a base station and all terminal stations have multiple antennas. In the SDMA system, simple beamforming is not efficient to achieve good performance due to cochannel interference. The proposed method is based on nullforming and characterized by antenna element selection at each terminal where the selected antenna pair satisfies the lowest spatial correlation condition in all combinations. The results obtained by computer simulations show selective diversity gain of the proposed method and performance improvement due to joint detection at each terminal.

When channel state information is known at a transmitter in multiple-input multiple-output systems, the optimum capacity is given by eigenmode channel division with water-pouring power control. In this eigenbeam-space division multiplexing (E-SDM), bit assignment to substreams based on the capacity is not optimum due to the fact that the number of assigned bits is expressed by a discrete quantity. In the paper, a method to assign both bit and transmit power to each substream based on the criterion minimizing total bit error rate (BER) is developed, and the BER performance is numerically analyzed in comparison to spatial division multiplexing (SDM). The simulation results assuming 5-transmit and 2-receive antennas show that the E-SDM provides about 10 dB gain compared to the conventional SDM at average BER of 10/sup -3/.

Increased pulmonary blood flow is believed to contribute to the development of pulmonary hypertension. We investigated the effect of overcirculation via an aortocaval fistula, on the development of monocrotaline-induced pulmonary hypertension in rats. Monocrotaline was administered 1 wk after the creation of an aortocaval fistula.Randomized, controlled study.Research laboratory of an academic institution.Male Sprague-Dawley rats.Overcirculation was induced by pneumonectomy and by surgical creation of aortocaval fistula. Pulmonary artery hypertension was induced by administration of monocrotaline.Aortic blood flow, Pao(2), and pulmonary arterial pressure were measured 4 wks later. A blinded investigator quantified pulmonary arterial neointimal formation in small pulmonary arteries. Compared with animals that received monocrotaline and/or underwent pneumonectomy but did not undergo aortocaval fistula, the presence of a surgical aortocaval fistula was associated with increased aortic blood flow (p.001), increased Pao(2) (p.001), and lower mean pulmonary arterial pressure (p.001). In addition, rats with aortocaval fistula had less pulmonary arterial neointimal formation than matched animals without an aortocaval fistula (p =.034).The presence of a surgical aortocaval fistula attenuates, rather than worsens, the development of monocrotaline-induced pulmonary hypertension in rats.

We propose new signal detection for space division multiplexing in a MIMO-OFDM system for high data rate transmission. Channel estimation is very important for suppressing the interference and demultiplexing the signals. In a wireless LAN system, such as IEEE 802.11a, only a few training symbols are inserted in each subcarrier. We propose a channel estimation method for the MIMO-OFDM system with two training symbols per subcarrier. The basic idea is to estimate the time-domain channel responses between the transmit and receive antennas. Applying the fast Fourier transform to them, the array response vectors for each subcarrier are calculated. Then, we can obtain the adaptive weights to cancel the interference. We show that employing training symbols having a lower condition number of a matrix used for the channel estimation improves the estimation accuracy.

We discuss downlink beamforming methods in consideration of a terminal having a joint detector function for space division multiple access (SDMA) in both a multi-input single-output (MISO) channel and a multi-input multi-output (MIMO) channel. We investigate two methods; a general beamformer, which maximizes the desired signal's power at the receiver (a transmit MRC diversity) and a null steering concept, which avoids the interference signal reaching the receiver. The computer simulation results show that the null steering concept yields better performance compared to the beam steering, even considering the joint detection at the receiver.

Multipath propagation causes serious performance degradation in a high-speed mobile TDMA system. We have proposed the adaptive antenna which copes with the multipath signals. These considerations have been limited to an uplink channel. We propose the basestation adaptive antennas both for the uplink and downlink channels. We assume an FDD/TDMA system where the frequencies are different between the uplink and downlink channels. The weight vectors proposed in this paper are determined using DOA estimation. The problem of the frequency difference in FDD is removed by this scheme. For the uplink channel, we can realize the path-diversity using the adaptive antenna with several weight vectors. For the downlink channel, we propose a single-beam adaptive antenna and two-beam one. It is shown that the combination of the two-beam basestation adaptive antenna and the mobile terminal with two-input (two antenna) MLSE equalizer shows better performance.

In SDMA, a spatial domain interference canceler applying a multistage processing concept to the MMSE multibeam adaptive array has an attractive feature that weak power signals can be detected in the successive stages after removing other strong power signals which are already detected. This idea can be enhanced to the reference timing estimation required in the MMSE algorithm. In this paper the spatial domain interference canceler introducing multistage timing estimation is proposed and its performance is evaluated by computer simulations. The results show that the timing estimation performance is highly improved.

In employing an adaptive array for TDD/SDMA at a base station, generally, the array pattern for the downlink is calculated from that for the uplink. Considering the angle spread in a Rayleigh fading channel, the time difference between the uplink and downlink causes the null position change on the optimum array pattern. We propose a weight estimation method for the downlink null steering. It is based on the indirect weight estimation using the channel response prediction. The computer simulations show that the proposed method improves the BER performance in the downlink, effectively.

It is difficult for the adaptive array to reduce interference signals efficiently from the received signals when the interference signals and desired signal are closely located. This is a serious problem for a spatial division multiple access (SDMA) system using the multibeam adaptive array as a multiuser detector. We propose a space domain multistage interference canceller (SD-MIC) for the SDMA. Its performance is evaluated in frame error rate (FER) by computer simulations, considering uplink environment in the Japanese personal handy-phone system (PHS). The results show the remarkable improvement in high spatial correlation situations.

In high-speed TDMA mobile communications, frequency-selective fading is a serious problem because a delay time difference between multipath signals is large in comparison with the symbol duration. We have proposed a spatial-domain path-diversity system using a multibeam adaptive antenna to reduce frequency-selective fading and to realize path-diversity. The multibeam adaptive antenna resolves multipath signals in the spatial domain, and combines the array outputs. We propose the application of the MUSIC algorithm to estimation of the time delays of multipath signals to make the incident signals coincide with a common reference signal. Because the MUSIC algorithm can estimate the time delays accurately, the BER performance of the proposed scheme is improved.

Hypertensive pulmonary vascular disease is characterized by abnor- prostanoids (7), which dilate reactive blood vessels and supmal proliferation of vascular endothelial and smooth muscle cells, press the growth of smooth muscle cells (8). Additional antileading to occlusion of pulmonary arterioles, pulmonary hyperten- proliferative strategies for treatment of vascular occlusive sion, right ventricular failure, and death. Compounds with antipro- diseases are warranted (9). liferative effects on vascular endothelial and smooth muscle cells, Our group has previously demonstrated that antiproliferasuch as 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reduc- tive drugs with no acute vasodilator properties effectively tase inhibitors, may prevent the development of experimental hy- attenuate vascular remodeling with neointimal formation, pertensive pulmonary vascular disease. Pneumonectomized rats in- pulmonary arterial hypertension, and right ventricular hyperjected with monocrotaline at 7 days develop severe hypertensive trophy in pneumonectomized, monocrotaline-injected rats (10, pulmonary vascular disease with neointimal formation. Rats were 11). The combination of pneumonectomy with monocrotaline randomized to receive either vehicle or treatment with the HMGCoA reductase inhibitor simvastatin (2 mg/kg per day). By Day injection results in more severe pulmonary arterial hyperten35, rats that received vehicle had higher mean pulmonary arterial sion (mean pulmonary arterial blood pressure [Ppa] 45 mm pressures (53 2 mm Hg) and right ventricular hypertrophy (right Hg) (10–12) than monocrotaline alone (Ppa 32 mm Hg) ventricle/[left ventricle plus septum] [RV/LVS] 0.78 0.09) (13–15). Importantly, only the combination of pneumonecthan rats in Group PMS5–35 that received simvastatin from Day 5 to tomy with monocrotaline injection produces neointimal for35 (mean pulmonary arterial pressure 27 3 mm Hg, RV/LVS mation and vascular obliteration of small pulmonary arteri0.34 0.08; p 0.001). Pulmonary vascular remodeling with neointi- oles that reproduces many of the pathological features of mal formation consisting of vascular smooth muscle cells was more human PPH (2, 9). severe in vehicle-treated rats (vascular occlusion score, 1.98 0.02) It is increasingly recognized that treatment with 3-hydroxthan in Group PMS5–35 (vascular occlusion score, 0.59 0.46; p ymethyl-3-methylglutaryl-coenzyme A (HMG-CoA) reduc

BACKGROUND Although malignant lymphomas of the central nervous system have been reported to be increasing in frequency, cerebellopontine (CP) angle lymphoma is rare and only 13 cases have been reported previously in the literature. CASE PRESENTATION A 63-year-old woman had progressive dizziness and nausea for 2 months. Computed tomography scanning and magnetic resonance imaging (MRI) revealed a mass lesion in the left CP angle, that was compressing the lateral-dorsal aspect of the pons and the fourth ventricle. This tumor was avascular on angiography. The tumor was surgically removed through a left lateral suboccipital approach. It was considered to arise from the subarachnoid space of the CP angle cistern. For some reason, the histologic diagnosis was not definitively made, and therefore radiation therapy was not planned. The tumor recurred within 50 days after the tumor excision. Surgical excision of the recurrent tumor was performed again. The histologic diagnosis was B-cell type malignant lymphoma. Radiation therapy was performed. In the 27 months since irradiation, a recurrent tumor has not been detected on MRI. CONCLUSIONS Although erosion and expansion of the internal auditory canal suggest an acoustic neurinoma, CP angle lymphoma can, in rare circumstances, erode the internal auditory canal. There are three distinct patterns in which malignant lymphomas occupy the CP angle: (1) an extra-axial CP angle lymphoma, (2) an intra-axial lymphoma extending to the CP angle, and (3) a leptomeningeal lymphoma presenting as a CP angle lesion. Although malignant lymphomas rarely occupy the CP angle, it should be considered in the differential diagnosis of CP angle tumors. It is desirable to obtain a frozen section in all CP angle tumors during surgery to identify the tumor, because aggressive removal is not necessary, but radiation therapy should additionally be performed for malignant lymphomas.

The quasi-optical antenna mixer system transforms radio frequency (RF) signal into intermediate frequency (IF) signal just after the system receives the RF and local oscillator's (LO) signal spatially [1]. We present a novel beam scanning system with the quasi-optical antenna-mixer array. In this paper, we describe the principle and the experimental results in the microwave band. The arrival direction of the RF signal can be controlled by the system without RF circuits such as phase shifters. Therefore, not only losses in RF circuits are reduced but also the system is easily designed because of its simple structure. This feature is an advantage in applying to the millimeter wave band.

The electrically elicited blink reflex (BR) was studied in 30 patients with meningomyelocele (MMC), including 21 with Chiari type II malformation. The relationship between the BR and brainstem auditory evoked potentials (BAEPs) is discussed with regard to its use-fulness in the evaluation of MMC's brainstem dysfunction. The following results were obtained: (1) The R2 component was abnormal in 90% of these patients. The BR disclosed subclinical lesions in the medulla oblongata which were not detected by BAEPs alone. (2) In all patients in whom the BAEPs suggested the presence of stretched cochlear nerves, the BR indicated the existence of some dysfunction of the medulla oblongata. (3) No close relationship was found between the dysfunction detected by the BR and the degree of hindbrain anomaly on the neuroimaging. (4) Combining results from assessment of the measurement of the BR and BAEPs permits evaluation of the function of the fifth, seventh, and eighth cranial nerves, as well as the brainstem including the medulla oblongata, which is more comprehensive than evaluation by neuroimaging alone.

Twenty patients with meningomyelocele (MMC) and shunted hydrocephalus, ranging in age from 3 to 23 years old, underwent serial recording of short-latency somatosensory evoked potentials (SEPs) to median nerve stimulation, on the basis of which to assess the evolution of dysfunction in the brainstem and its connections (cervical spinal cord, cervical nerve roots, lower cranial nerves). Eighteen patients had Chiari type II malformations, none of which was symptomatic. In all 20 patients, serial SEP recordings were obtained repeatedly after periods ranging from 2 to 7 years. The results were as follows: (1) the ratio of $$EP - N\overline {13}$$ interpeak latencies (IPLs) to body height (BH) tended to lengthen gradually after starting in the normal range with growth. (2) In contrast, the ratio $$N\overline {13} - N\overline {20}$$ IPLs/BH decreased continously to the normal range with growth, after initial prolongation. These findings and our earlier studies of brainstem auditory evoked potentials suggest that compression and traction result in strangulation of the cervical spinal cord and kinked medulla as well as stretching of the cervical nerve roots and lower cranial nerves. However, primary intrinsic functional disorders of the brainstem appeared to improve gradually during growth. The natural history of Chiari type II malformations involves these opposing dynamic phenomena in the hindbrain and its connections.

Abstract 1110 Procarboxypetidase B-2 (pro-CPB2) (also termed thrombin-activatable fibrinolysis inhibitor, TAFI) is activated by the thrombin/thrombomodulin complex to generate a basic carboxypeptidase (CPB2). Fibrin and complement C5a have been shown to be physiological CPB2 substrates, but the role of CPB2 in sepsis is unclear. We hypothesized that in polymicrobial sepsis, the CPB2 KO mice would have exacerbated disease because there would be enhanced activation of C5a, leading to an augmented inflammatory response and tissue injury. To our surprise, in a polymicrobial sepsis model in which the cecum was ligated and punctured (CLP), CPB2 deficient mice had a significant improvement in survival compared to wild type (WT) mice (p = 0.021) (Fig. 1). The median survival time of 3 days in WT mice was extended to 4 days in CPB2 KO mice (p = 0.015). Lung edema as measured by wet/dry lung weight ratio was decreased from 4.4 in the WT mice to 2.5 in the CPB2 KO mice (p = 0.0001) at 48 hr after CLP (Fig. 2). Peritoneal lavage fluid levels of protein and the amount of cell infiltration into the peritoneum at 48 hr was lower in CPB2 KO than WT mice. There was less liver damage assessed as AST and ALT in plasma in the CPB2 KO mice at 48 hr than in WT mice while there was a trend to an increase in BUN suggesting kidney damage in WT mice. There was a greater decrease in the white blood cell count of WT mice than CPB2 KO mice with a drop in lymphocyte numbers accounting for most of that decrease. Inflammatory mediators such as IL-6 and total C5a were lower in plasma from CPB2 KO mice at 6 hr after CLP than in WT plasma. The data suggest that WT mice in this model underwent multiple organ failure leading to their death and the CPB2 deficient mice were protected from the consequences of CLP. Overall these data show that lack of CPB2 protects against polymicrobial sepsis with a concomitant reduction in inflammation. Further studies are underway to determine which substrate is key to the prolonged survival of CPB2 deficient mice in this model. Disclosures: No relevant conflicts of interest to declare.

Intracellular recordings were made from neurons in rabbit and feline vesical parasympathetic ganglia in vitro. In response to cathodal current injection (0.1-1 nA for 2-20 ms) the majority of rabbit neurons (229 out of 250) exhibited a single action potential that was followed by a fast and slow after-hyperpolarization (sAHP neuron). The remainder of the cells exhibited an action potential followed by only a fast after-hyperpolarization (fAHP neuron). fAHP neurons did not exhibit anomalous rectification and a spontaneous rhythmic hyperpolarization, which were common membrane properties in sAHP neurons. In response to a train of cathodal current pulses (5-20 Hz for 0.1-10 s), fAHP neurons exhibited action potentials followed by a post-tetanic depolarization (PTD). The PTD was associated with a decrease in membrane input resistance. The amplitude and duration of the PTD were a function of the number of action potentials in the train. The amplitude of the PTD was increased by membrane hyperpolarization and its estimated reversal potential was approximately -30 mV. Low-chloride solution and intracellular injection of chloride ions augmented the amplitude and duration of the PTD, whereas low-sodium, high-potassium and low-potassium solutions did not affect them. Tetraethylammonium (5-10 mM) and barium (0.5-1 mM) increased the amplitude and duration of the PTD. Nominal calcium-free solutions and omega-conotoxin (500 nM) abolished the PTD. The data suggest that activation of chloride channels by calcium influx through omega-conotoxin-sensitive calcium channels mediates the PTD. Repetitive stimulation of the pelvic nerve evoked a train of orthodromic action potentials followed by the PTD of fAHP neurons. (+)-Tubocurarine (10 microM) and hexamethonium (200 microM), but not atropine (1 microM), abolished orthodromic action potentials and the PTD, whereas these cholinergic antagonists did not depress the PTD evoked by direct action potentials. In summary, the data suggest that the PTD may function as a slow synaptic potential in fAHP neurons. This appears likely because neither slow excitatory nor inhibitory postsynaptic potentials are present in neurons of rabbit vesical parasympathetic ganglia. In contrast, slow inhibitory and excitatory postsynaptic potentials were recorded from neurons in feline vesical parasympathetic ganglia.

数十Gbit/s以上の超高速通信が必要になった場合，MIMO伝送が必須技術となることは容易に想像できる．しかし，実際に超高速伝送を実現できるかどうかは，アンテナ本数のみならず，周波数帯，伝搬環境，実装技術に大きく依存する．特に超高速伝送が使用されると考えられる見通しのある解放空間では，空間相関が高くなるため，MIMO伝送の効果が減少する．したがって，アンテナ配置や伝搬構造の能動的最適化など，改善手法について述べる．

Brain stem auditory-evoked potentials (BAEPs) were recorded in 30 patients with meningomyelocele and shunted hydrocephalus ranging in age from birth to 33 years. Twenty-two of them had Chiari II malformation, one of which was symptomatic. In 22 cases, including 15 with Chiari II malformation, BAEPs were recorded repeatedly after periods ranging from 18 months to 7 years. The results were as follows: (1) III–V interpeak latency (IPL) decreased progressively from prolonged to the normal range with growth until 25 years of age; (2) I–III IPL tended to prolong gradually from the normal range; (3) these findings may indicate that the natural history of Chiari II malformation is delayed maturation of the brain stem and intensification in the elongation and stretching of the hindbrain and lower cranial nerves.

1. Voltage-clamp recordings were made from neurones of vesical pelvic ganglia isolated from the rabbit urinary bladder. A rhythmic outward current, ISH, which corresponds to the spontaneous hyperpolarization, occurred at fairly constant intervals in fifty-eight of eighty-four neurones superfused with Krebs solution. The peak amplitude of the ISH was 0.5 +/- 0.2 nA (n = 48; mean +/- S.E.M.). 2. The ISH was eliminated in a Krebs solution containing nominally zero calcium and 12 mM-magnesium. Lowering the temperature of the superfusing solution from 36 to 22 degrees C also inhibited the occurrence of the ISH. 3. Bath application of caffeine increased the frequency of ISH. In contrast, ryanodine and procaine reversibly blocked ISH. 4. In thirty-four of fifty-eight neurones, the ISH was composed of two current components, an initial fast ISH with duration of 1-10 s and a slow ISH lasting 15-60 s. In the remaining twenty-four neurones, ISH showed only the fast component. 5. The fast ISH was associated with an increased membrane conductance and the slow ISH was associated with a decreased membrane conductance. The reversal potentials of the fast and the slow ISH were -88 +/- 7 mV (n = 4) and -30 +/- 6 mV (n = 4), respectively. 6. Tetraethylammonium (5 mM) and barium (1 mM) blocked the fast ISH but not the slow ISH. Intracellular caesium injected by ionophoresis through a Cs(+)-filled microelectrode blocked the fast ISH, without affecting the slow ISH. Apamin and (+)-tubocurarine selectively suppressed the fast component of the ISH. 7. Substitution of isethionate (67 mM) for chloride increased the amplitude of the slow ISH and shifted the reversal potential of the slow ISH to +1 +/- 8 mV (n = 5). A slow ISH with amplitude of 0.1-1 nA and was still observed in a low-sodium (26.2 mM) solution. The stilbene derivative, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulphonic acid (SITS), a chloride channel blocker, suppressed the slow ISH. 8. These results suggest that ISH is composed of two distinct calcium-dependent currents, a fast ISH produced by activation of potassium conductance and a slow ISH produced by inactivation of chloride conductance. 9. The after-hyperpolarization (AHP) following the action potential was also composed of apamin-sensitive and insensitive spontaneous hyperpolarizing oscillations. The apamin-insensitive component of IAHP was increased by lowering external chloride activity, while it was depressed by SITS.

46 upper and lower molars with furcation grade II involvement were selected from 16 patients with periodontal disease. The teeth were randomly allocated to the following groups according to treatment; (1) 4 consecutive administrations of tetracycline-immobilized cross-linked collagen film (TC film) at intervals of 1 week (TC group); (2) 1 root planing treatment (RP group); (3) combination treatment (TC + RP group); (4) no treatment (control group). The therapeutic effects of each treatment were compared both clinically and micro-biologically. Records of plaque index, gingival index, bleeding on probing, probing depth, probing attachment level and microscopic counts were obtained at 0, 4, 6 and 8 weeks. The results showed marked decreases in probing depth and density of micro-organisms in both the RP and TC + RP groups. In particular, the TC + RP group was characterized by a decreased rate of bleeding on pocket probing and an increased probing attachment gain. The above findings demonstrated that root planing is effective in the treatment of furcation involvement and that the effects are enhanced by the local administration of TC films.

1. Voltage-clamp recordings were made from neurones in rabbit vesical pelvic ganglia by using single microelectrodes filled with 2 M-caesium chloride. Neurones were superfused with Krebs solution containing 300 nM-tetrodotoxin and 50 mM-tetraethylammonium. 2. Depolarizing voltage jumps activated inward currents followed by slowly decaying inward tail currents at -30 to +30 mV, which were accompanied by a large increase in membrane conductance. Both the inward current and tail current were blocked by cobalt (2 mM) or in a Krebs solution containing zero calcium and 12 mM-magnesium. 3. Substitution of barium for calcium enhanced the inward current, while it strongly reduced the tail current. Strontium substitution still exhibited both the inward current and the tail current. 4. Lowering external chloride activity increased the tail current amplitudes without affecting an initial calcium current. The reversal potentials of the tail current, measured using a twin-pulse protocol, were -18 +/- 5 mV (mean +/- S.E.M., n = 8) and +5 +/- 3 mV (n = 5) in Krebs solution and low-chloride (62 mM) solution, respectively, suggesting a calcium-dependent chloride current. 5. Stilbene derivatives, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulphonic acid (SITS, 0.01-1 mM) and 4,4'-diisothiocyanostilbene-2,2'-disulphonic acid (DIDS, 0.01-1 mM), reversibly and concentration dependently depressed the tail current without affecting the calcium current. 6. Transient (T) and sustained (N and L) types of calcium current were likely to co-exist in neurones of the rabbit pelvic ganglia. Calcium-dependent chloride current was activated by N- and L-type calcium currents but not by T-type current. 7. Activation of the tail current at 0 to +20 mV was described by a single-exponential function. The tail current decayed exponentially at a holding membrane potential of -70 mV. Tail decay time constants were dependent on voltage and duration of the step command. 8. Substantial activation of the calcium-dependent chloride conductance could occur during a post-tetanic after-potential when pelvic ganglia neurones fired action potentials repetitively.

Properties of voltage-dependent barium current (IBa) were examined in parasympathetic neurons of the rabbit urinary bladder, in vitro. Transient low-threshold IBa was evoked by voltage jump from a holding potential (Vh) of -100 to -50 mV. Additional transient high-threshold IBa appeared at potentials more positive than -30 mV. Long-lasting high-threshold IBa was evoked at 0 to -20 mV. High-threshold currents were blocked by omega-conotoxin but not by dihydropyridines.

The latent plasma carboxypeptidase thrombin-activatable fibrinolysis inhibitor (TAFI) is activated by thrombin/thrombomodulin on the endothelial cell surface, and functions in dampening fibrinolysis. We recently showed that TAFIa efficiently inactivates bradykinin, C5a, and thrombin-cleaved osteopontin, suggesting that it may have a broad anti-inflammatory role. In this study, we examined the pulmonary inflammatory responses in a C5a-induced alveolitis model in wild-type (WT) and TAFI deficient mice. TAFI deficient mice had been backcrossed into a pure C57/B6 background. C5a was instilled into the trachea of anesthetized mice, which were then allowed to recover. Six hours later, bronchiole alveolar lavage (BAL) was performed and the extent of pulmonary inflammation determined. C5a caused a dose-dependent increase in cell counts (WBC/ul) in the BAL fluids in WT mice (saline control, 5.3±4.1 (mean±SD); C5a at 0.05 mg/ml, 28.7±8.5, C5a at 0.1 mg/ml, 60.4±23.8; n=6 for saline and low-dose C5a, n=12 for high dose C5a; p < 0.0005 and < 0.0001 for low-dose and high-dose C5a compared to saline control respectively). Significantly increased BAL cell counts in the TAFI deficient mice in response to C5a stimulation were noted (saline control, 3.3±3.9; low-dose C5a 70±11.2; high-dose C5a 159.6±58.7; n=6 for saline and low-dose C5a, n=12 for high dose C5a; p < 0.00001 and < 5E-0.6 respectively), representing ~2.4–2.6 fold increase in BAL cell counts in the TAFI deficient mice. Determinations of the wet/dried lung weight ratios, an index of pulmonary edema, showed similarly significant results (WT mice: 4.1±0.14, 4.25±0.1, 4.52±0.15 and TAFI-deficient mice: 4.27±0.41, 5.3±0.53, 5.77±0.62 for saline control, low- and high-dose C5a respectively). Our data indicate that in the absence of TAFI, the chemotactic and inflammatory effects of C5a in pulmonary inflammation were enhanced. We are in the process of testing whether E229K thrombin, which selectively activates protein C and TAFI, will ameliorate the C5a alveolitis response in WT mice. Our results support our thesis that the function of TAFIa is not restricted to fibrinolysis. It has a broad anti-inflammatory role and may serve as a homeostatic counterbalance to thrombin’s inflammatory functions.