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In hippocampal CA1 neurons of wild-type mice, a short tetanus (15 or 20 pulses at 100 Hz) or a standard tetanus (100 pulses at 100 Hz) to a naive input pathway induces long-term potentiation (LTP) of the responses. Low-frequency stimulation (LFS; 1000 pulses at 1 Hz) 60 min after the standard tetanus reverses LTP (depotentiation [DP]), while LFS applied 60 min prior to the standard tetanus suppresses LTP induction (LTP suppression). We investigated LTP, DP, and LTP suppression of both field excitatory postsynaptic potentials and population spikes in CA1 neurons of mice lacking the inositol 1,4,5-trisphosphate (IP3) receptor (IP3R)-binding protein released with IP3(IRBIT). The mean magnitudes of LTP induced by short and standard tetanus were not different in mutant and wild-type mice. In contrast, DP and LTP suppression were attenuated in mutant mice, whereby the mean magnitude of responses after LFS or tetanus were significantly greater than in wild-type mice. These results suggest that, in hippocampal CA1 neurons, IRBIT is involved in DP and LTP suppression, but is not essential for LTP. The attenuation of DP and LTP suppression in mice lacking IRBIT indicates that this protein, released during or after priming stimulations, determines the direction of LTP expression after the delivery of subsequent stimulations.

In CA1 neurons of guinea pig hippocampal slices, long-term potentiation (LTP) was induced in field excitatory postsynaptic potentials (EPSPs) or population spikes (PSs) by the delivery of high-frequency stimulation (HFS, 100 pulses at 100 Hz) to CA1 synapses, and was reversed by the delivery of a train of low-frequency stimulation (LFS, 1000 pulses at 2 Hz) at 30 min after HFS (depotentiation), and this effect was inhibited when test synaptic stimulation was halted for a 19-min period after HFS or for a 20-min period after LFS or applied over the same time period in the presence of an antagonist of N-methyl-D-aspartate receptors (NMDARs), group I metabotropic glutamate receptors (mGluRs), or inositol 1, 4, 5-trisphosphate receptors (IP3Rs). Depotentiation was also blocked by the application of a Ca2+/calmodulin-dependent protein kinase II (CaMKII) inhibitor or a calcineurin inhibitor applied in the presence of test synaptic input for a 10-min period after HFS or for a 20-min period after LFS. These results suggest that, in postsynaptic neurons, the coactivation of NMDARs and group I mGluRs due to sustained synaptic activity following LTP induction results in the activation of IP3Rs and CaMKII, which leads to the activation of calcineurin after LFS and depotentiation of CA1 synaptic responses.

We investigated the role of inositol 1,4,5-trisphosphate receptors (IP3Rs) activated by preconditioning low-frequency afferent stimulation (LFS) in the subsequent induction of long-term potentiation (LTP) in CA1 neurons in hippocampal slices from mature guinea pigs. Induction of LTP in the field excitatory postsynaptic potential or the population spike by the delivery of high-frequency stimulation (HFS, a tetanus of 100 pulses at 100 Hz) to the Schaffer collateral–commissural pathway to CA1 neuron synapses was suppressed when group I metabotropic glutamate receptors (mGluRs) were activated prior to the delivery of HFS. LTP induction was also suppressed when CA1 synapses were preconditioned 60 min before HFS by LFS of 1000 pulses at 1 Hz and this effect was inhibited when the test stimulation delivered at 0.05 Hz was either halted or applied in the presence of an antagonist of N-methyl-d-aspartate receptors, group I mGluRs, or IP3Rs during a 20-min period from 20 to 40 min after the end of LFS. Furthermore, blockade of group I mGluRs or IP3Rs immediately before the delivery of HFS overcame the effects of the preconditioning LFS on LTP induction. These results suggest that, in CA1 neurons, after a preconditioning LFS, activation of group I mGluRs caused by the test stimulation results in IP3Rs activation that leads to a failure of LTP induction.

An Examination of Factors Related to Work‐to‐family Conflict among Employed Men and Women in Japan: Michiko Kato, et al. Department of Health Sociology, Division of Health Sciences and Nursing, Graduate School of Medicine, The University of Tokyo The aims of this study of Japanese married employees were: 1) to examine the relationship between work‐related factors and work‐to‐family conflict (WFC); 2) to examine the relationship between WFC and fatigue and depression; and 3) to explore the role of family togetherness in a path between WFC and health. A cross‐sectional survey was conducted among employees belonging to a labor union federation of the chemical industry. All analyses were conducted by subgroup according to gender and parental status. Data was collected from 12 companies located in the Tokyo metropolitan area from September to October 2005. The data of 961 married employees were analyzed. The main findings by regression analyses were: 1) high job demands, low job control, and unsupportive work‐family culture were associated with high level of WFC; 2) WFC was positively associated with fatigue and depression regardless of gender and parental status; and 3) maintaining family togetherness was slightly, yet significantly associated with fatigue in the father group. WFC was unfavorably related to fatigue and depression in both genders regardless of parental status, and plays a role linking unfavorable work situations and health. As possible work‐related factors of WFC, the data indicate not only individual workplace variables but also an organizational support. Additionally, maintaining family togetherness appears to benefit fathers by preventing fatigue. Strategies for reduction of WFC are therefore necessary to promote health among married workers of both genders.

Keratoconus is a chronic, noninflammatory, degenerative disease of the cornea that has an onset in young adulthood. The objective of this study was to evaluate vision-related quality of life (VR-QOL) in patients with keratoconus by using the Japanese version of the National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25).

Evidence suggests that dopamine hyperfunction in schizophrenia blocks direct sensory information flow to CA1 pyramidal cells via the temporoammonic path. Owing to the high prevalence of smoking in schizophrenics, we examined whether nicotine modulates synaptic transmission in the temporoammonic path. Application of nicotine suppressed temporoammonic synaptic transmission as in the case of dopamine application. The suppressive effect of nicotine, however, disappeared in chronic nicotine-exposed hippocampi, suggesting the loss of nicotinic modulation of transmission in the temporoammonic path. In addition, the dopaminergic modulation of temporoammonic synaptic transmission decreased after chronic nicotine treatment. These observations suggest that chronic nicotine exposure affects the normal operation of hippocampal circuits.

The Effects of Pre‐Entry Career Maturity and Support Networks in Workplace on Newcomers' Mental Health: Kaoru Kawai, et al. Department of Health Sociology, School of Health Science and Nursing, The University of Tokyo—The present study examined the effects of pre‐entry experiences (i.e. career maturity), as well as support networks (i.e. informational and friendship), on newcomers' mental health (i.e. depression, self‐esteem, psychosomatic symptoms, and work motivation). We performed a longitudinal study of 890 men and women who first entered the workplace in 2003. Surveys were distributed at two time points: just prior to entering the workplace, and two months after entering. Results indicated that career maturity related positively to newcomers' mental health, and newcomers with high career maturity were more successful in establishing positive relationships with superiors and co‐workers. Although, informational support networks positively related to work motivation, friendship networks did not show any direct effects on mental health. These results underscore the crucial roles of career maturity and informational networks in facilitating the transition to the workplace. The results also provide empirical support for an expanded view of the importance of pre‐entry experiences to workplace newcomers' mental health.

The Effects of Pre-Entry Career Maturity and Support Networks in Workplace on Newcomers’ Mental Health: Kaoru Kawai, et al. Department of Health Sociology, School of Health Science and Nursing, The University of Tokyo—The present study examined the effects of pre-entry experiences (i.e. career maturity), as well as support networks (i.e. informational and friendship), on newcomers’ mental health (i.e. depression, self-esteem, psychosomatic symptoms, and work motivation). We performed a longitudinal study of 890 men and women who first entered the workplace in 2003. Surveys were distributed at two time points: just prior to entering the workplace, and two months after entering. Results indicated that career maturity related positively to newcomers’ mental health, and newcomers with high career maturity were more successful in establishing positive relationships with superiors and co-workers. Although, informational support networks positively related to work motivation, friendship networks did not show any direct effects on mental health. These results underscore the crucial roles of career maturity and informational networks in facilitating the transition to the workplace. The results also provide empirical support for an expanded view of the importance of pre-entry experiences to workplace newcomers’ mental health.

Abstract According to the equilibrium point hypothesis of voluntary motor control, control action of muscles is not explicitly computed, but rather arises as a consequence of interaction between moving equilibrium position, current kinematics and stiffness of the joint. This approach is attractive as it obviates the need to explicitly specify the forces controlling limb movements. However, many debatable aspects of this hypothesis remain in the manner of specification of the equilibrium point trajectory and muscle activation (or its stiffness), which elicits a restoring force toward the planned equilibrium trajectory. In this study, we expanded the framework of this hypothesis by assuming that the control system uses the velocity measure as the origin of subordinate variables scaling descending commands. The velocity command is translated into muscle control inputs by second order pattern generators, which yield reciprocal command and coactivation commands, and create alternating activation of the antagonistic muscles during movement and coactivation in the post-movement phase, respectively. The velocity command is also integrated to give a position command specifying a moving equilibrium point. This model is purely kinematics-dependent, since the descending commands needed to modulate the visco-elasticity of muscles are implicitly given by simple parametric specifications of the velocity command alone. The simulated movements of fast elbow single-joint movements corresponded well with measured data performed over a wide range of movement distances, in terms of both muscle excitations and kinematics. Our proposal on a synthesis for the equilibrium point approach and velocity command, may offer some insights into the control scheme of the single-joint arm movements.

The role of inositol 1, 4, 5-trisphosphate receptors (IP3Rs) in long-term potentiation (LTP) and long-term depression (LTD) was studied in CA1 neurons in guinea pig hippocampal slices. In standard solution, short tetanic stimulation consisting of 15 pulses at 100 Hz induced LTP, while three short trains of low-frequency stimulation (LFS; 200 pulses at 1 Hz) at 18-min intervals or one long train of LFS (1000 pulses at 1 Hz) induced stable LTD in both the slope of the field EPSP (S-EPSP) and the amplitude of the population spike (A-PS). Bath application of 2-aminoethoxydiphenyl borate (2-APB), an IP3R antagonist, or of alpha-methyl-4-carboxyphenylglycine (MCPG), a wide-spectrum metabotropic glutamate receptor antagonist, during weak tetanic stimulation significantly increased the magnitude of the LTP in both the S-EPSP and A-PS. Three short trains of LFS or one long train of LFS delivered in the presence of 2-APB or MCPG did not induce LTD, but elicited LTP. Based on these results, we conclude that, in hippocampal CA1 neurons, IP3Rs play an important role in synaptic plasticity by attenuating LTP and facilitating LTD.

The present study has investigated the role of ATP in the induction of synaptic plasticity, using local application of ATP by picopump administration into the stratum radiatum of guinea pig hippocampal region CA1. Excitatory postsynaptic currents (EPSCs) evoked by stimulation of Schaffer collateral/commissural afferents synapsing on CA1 pyramidal cells of hippocampal slices were monitored in voltage‐clamp mode, using whole‐cell recording. Brief local application of ATP (1 mM) induced an inward current, usually consisting of early‐ and late‐phase components. Because the late‐phase component of an ATP‐induced current was largely inhibited by Ca2+‐free solution, this component is supposed to depend on extracellular Ca2+. After local application of ATP, long‐term synaptic modification of EPSCs was induced: LTP was detected in neurons exhibiting a small late Ca2+current, while LTD was obtained from recordings showing a large late Ca2+current in response to ATP application. There was a statistically significant correlation between the magnitude of long‐term plastic changes and the size of Ca2+currents in response to ATP application. Furthermore, there was significant difference between the average size of the Ca2+current in the LTP group and the size in the LTD group. These results suggest that a small Ca2+influx in response to ATP application induces LTP, whereas a large one induces LTD in guinea pig hippocampal CA1 neurons. Hippocampus 2003;13:81–92. © 2003 Wiley‐Liss, Inc.

The present study has investigated the role of ATP in the induction of synaptic plasticity, using local application of ATP by picopump administration into the stratum radiatum of guinea pig hippocampal region CA1. Excitatory postsynaptic currents (EPSCs) evoked by stimulation of Schaffer collateral/commissural afferents synapsing on CA1 pyramidal cells of hippocampal slices were monitored in voltage-clamp mode, using whole-cell recording. Brief local application of ATP (1 mM) induced an inward current, usually consisting of early- and late-phase components. Because the late-phase component of an ATP-induced current was largely inhibited by Ca²⁺-free solution, this component is supposed to depend on extracellular Ca²⁺. After local application of ATP, long-term synaptic modification of EPSCs was induced: LTP was detected in neurons exhibiting a small late Ca²⁺ current, while LTD was obtained from recordings showing a large late Ca²⁺ current in response to ATP application. There was a statistically significant correlation between the magnitude of long-term plastic changes and the size of Ca²⁺ currents in response to ATP application. Furthermore, there was significant difference between the average size of the Ca²⁺ current in the LTP group and the size in the LTD group. These results suggest that a small Ca²⁺ influx in response to ATP application induces LTP, whereas a large one induces LTD in guinea pig hippocampal CA1 neurons. Hippocampus 2003;13:81–92. © 2003 Wiley-Liss, Inc.

A 60-year-old woman who had undergone repair of an atrial septal defect was readmitted to the hospital with dyspnea, abdominal distention, and leg edema 31 months after surgery. An echocardiogram demonstrated massive pericardial effusion. Cardiac catheterization revealed elevation and equilibrium of the 4-chamber diastolic pressure and a dip-and-plateau pattern in the right and the left ventricular pressures. Despite removal of pericardial fluid by pericardiocentesis, the findings and symptoms did not improve. The patient underwent both parietal and visceral pericardiectomy after which striking hemodynamic and symptomatic improvement occurred. Effusive-constrictive pericarditis is uncommon but should be considered in patients with refractory heart failure and massive pericardial effusion showing no improvement after removal of pericardial fluid.

1. Using simultaneous recordings of the field EPSP and the population spike in the CA1 neurons of guinea pig hippocampal slices, we confirmed that delivery of a high-frequency stimulation (tetanus: 100 pulses at 100 Hz) produced robust long-term potentiation of synaptic efficacy (LTP) in two independent components, a synaptic component that increases field excitatory postsynaptic potentials (EPSPs) and a component that results in a larger population spike amplitude for a given EPSP size (E-S potentiation). 2. In the same cells, reversal of LTP (depotentiation; DP) in the field EPSP and in the E-S component is achieved by delivering low-frequency afferent stimulation (LFS:1 Hz, 1000 pulses) 20 min after the tetanus. 3. When the tetanus or LFS was applied to CA1 inputs in the presence of an adenosine A1receptor antagonist, 8-cyclopentyltheophylline (1 μM), the field EPSP was enhances in LTP and attenuated in DP, while the E-S relationship was not significantly affected in either LTP or DP. 4. When similar experiments were performed using an A2receptor antagonist, CP-66713 (10 μM), the field EPSP was blocked in LTP but facilitated in DP, while E-S potentiation was enhanced during both LTP and DP. 5. The results show that endogenous adenosine, acting via A1or A2receptors, modulates both the synaptic and the E-S components of the induction and reversal of LTP. Based on the results, we discuss the key issue of the contribution of these receptors to the dynamics of neuronal plasticity modification in hippocampal CA1 neurons.

Abstract: This study was undertaken to examine the longterm survival rates of patients following abdominal aortic aneurysm (AAA) repair in comparison with an age-matched normal population, and to determine by multivariate analysis the factors influencing long-term survival. Of 125 patients who underwent AAA repair prior to July 1986, 13 died during hospitalization. Of these 13 patients, 6 who suffered aneurysmal rupture all died within 30 days. The survival rate of patients with ruptured aortic aneurysms was significantly lower than that of those with nonruptured aneurysms. Of the 112 patients surviving hospitalization, 85 died within 0.48 to 24 years after their operation. The long-term survival rate of patients who had suffered a preoperative cardiovascular event was significantly lower than that of those who had not suffered a preoperative cardiovascular event. The actual survival rate was significantly lower than the expected survival rate. According to a multivariate analysis, the significant predictors of late survival were age, aneurysmal rupture, and chronic renal failure in all the patients, and age, chronic renal failure, and pre- and postoperative cardiovascular events in patients who did not die in hospital. These findings indicate the importance of improving immediate perioperative management of ruptured AAA and that cardiovascular events should be prevented, or treated during long-term follow-up.

The relationship of prostaglandin E2,of which a large amount is produced in various neoplasms, and hematogenous distant metastases was investigated in a total of 44 colorectal cancer patients because of its varied pathophysiologic potentials. The authors found significantly high levels of PGE2in local venous blood draining the carcinoma and in peripheral blood in cases with liver or lung metastasis, as well as a significantly large amount of PGE2production in the carcinoma tissue. The results suggest that increased local blood PGE2could enhance the metastasis formation, and increased peripheral blood PGE2may be useful in the detection of such metastasis in colorectal cancer.

Smoothness of movement is an inherent characteristic of the motor repertoire of primates. According to the minimum hand jerk model, a major feature of motor coordination in two-joint upper limb movements by humans in the horizontal plane is the production of the smoothest possible movement of the end effector, the hand (‘hand version’). In the present study, this model was extended to the formation of the trajectory of the centre of mass (CMt) of the whole arm system (‘CMt version’), and its importance for the shaping of multijoint movements was tested against the classical ‘hand version’. During point-to-point movements between many pairs of targets in the work space, the movements of the CMt showed lower changes of torque than in movements of the hand on a straight path. Furthermore, the CMt version of the minimum jerk model reproduced the curved hand trajectory that can be observed in actual human performance. Under the assumption that the smoothness criterion is induced by a high-level motor coordination, our results suggest that CMt-based planning can be an alternative strategy for joint coordination. It offers the advantage of the simplified scaling of joint torques which are suitable for execution of planned movements.

Abstract: We report two cases of a membranous stenosis of the hepatic portion of the inferior vena cava. Membranotomy was performed with a specially designed instrument similar to a Tubbs' dilator following balloon membranotomy. During the procedures, ultrasonographic observations were made and this technique was confirmed to be effective for proper placing of a balloon and a dilator in the stenotic portion. Follow-up evaluation of the procedures was also feasible with this ultrasonic aid.

Abstract: We report herein the case of a 47-year-old woman of the Jehovah's Witness faith in whom Y-grafting for a ruptured abdominal aortic aneurysm was successfully performed without a homologous blood transfusion. We used a Cell Saver (Haemonetics, Braintree, MA, USA) red cell salvaging device and an aortic occlusion balloon catheter, and performed gentle and minimal dissection during the operation. Postoperatively, the patient was kept heavily sedated and required hypothermic therapy for only 14 h. We treated her severe anemia using conventional drugs, including iron and folic acid, and her hemoglobin increased smoothly. Although her hemoglobin level decreased to 2.8 g/dl during the operation, her postoperative course was uneventful.

Abstract: Five transvenous instrumental membranotomies were performed in four patients with membranous obstruction of the hepatic segment of the inferior vena cava. Membranotomy was done with a specially designed instrument similar to a Tubbs' dilator, which was inserted through femoral or the right internal jugular veins. Pressure gradients across the membrane disappeared after membranotomy and the release of the stenosis was confirmed by angiography and ultrasonography. One patient needed a second membranotomy because of recurrent stenosis 7 years after the initial procedure.

Abstract: An 18-year-old man involved in a traffic accident presented with a left-sided hemothorax. After undergoing left chest tube drainage, he showed temporary stable hemodynamics for 7h. Later, an emergency left thoracotomy was performed because of abrupt, hemorrhagic shock. The intima and media of the descending thoracic aorta was completely transected, and a tube graft was successfully interposed with a simple aortic clamp in 47 min. The patient was eventually discharged from the hospital with no sequelae, such as paraplegia.

We created an atrial septal defect (ASD) using a Ferris–Smith–Kerrison bone punch under transesophageal echocardiographic monitoring for infants with complex congenital heart diseases, eg, transposition of the great arteries. We describe a safe and easy technique of ASD creation instead of Blalock–Hanlon operation.