Effects of Statin Plus Ezetimibe on Coronary Plaques in Acute Coronary Syndrome Patients with Diabetes Mellitus: Sub-Analysis of PRECISE-IVUS Trial

Aim: Coronary plaque regression is weak in acute coronary syndrome (ACS) patients with diabetes mellitus (DM). We evaluated whether dual lipid-lowering therapy (DLLT) with ezetimibe and atorvastatin attenuates coronary plaques in ACS patients with DM.

Methods: The prospective, randomized controlled, multicenter PRECISE-IVUS (Plaque Regression with Cholesterol Absorption Inhibitor or Synthesis Inhibitor Evaluated by Intravascular Ultrasound) trial assigned 246 patients undergoing percutaneous coronary intervention to DLLT or atorvastatin monotherapy and evaluated IVUS-derived changes in percent atheroma volume (ΔPAV), at baseline and 9–12-month follow-up, in 126 ACS cases, including 25 DM patients. The atorvastatin dose was up-titrated to achieve low-density lipoprotein cholesterol (LDL-C) < 70 mg/dL.

Results: In DM patients, the monotherapy group (n = 13) and the DLLT group (n = 12) showed a similar prevalence of coronary risks and baseline lipid profiles. During the study, the change in LDL-C level was similar between DM and non-DM patients. Compared with non-DM patients, DM patients showed weaker regression of ΔPAV by DLLT than those who underwent monotherapy (DM: −2.77 ± 3.47% vs. −0.77 ± 2.51%, P = 0.11; non-DM: −2.01 ± 3.36% vs. −0.08 ± 2.66%, P = 0.008). The change in LDL-C level was not correlated with ΔPAV in non-DM patients, but there was significant correlation between the change in LDL-C level and ΔPAV in DM patients (r = 0.52, P = 0.008).

Conclusions: ACS patients with DM showed weaker coronary plaque regression than their counterparts. A significant correlation between the change in LDL-C level and ΔPAV in DM patients suggested that more intensive lipid-lowering therapy is required in ACS patients with DM.

2D discontinuous piecewise linear map: Emergence of fashion cycles

We consider a discrete-time version of the continuous-time fashion cycle model introduced in Matsuyama, 1992. Its dynamics are defined by a 2D discontinuous piecewise linear map depending on three parameters. In the parameter space of the map periodicity, regions associated with attracting cycles of different periods are organized in the period adding and period incrementing bifurcation structures. The boundaries of all the periodicity regions related to border collision bifurcations are obtained analytically in explicit form. We show the existence of several partially overlapping period incrementing structures, that is, a novelty for the considered class of maps. Moreover, we show that if the time-delay in the discrete time formulation of the model shrinks to zero, the number of period incrementing structures tends to infinity and the dynamics of the discrete time fashion cycle model converges to those of continuous-time fashion cycle model.

Quantum chemical approach for highly durable anion exchange groups in solid-state alkaline fuel cells

The durability of anion exchange groups against OH⁻ ion that decomposed fast.

Amorphous nanosilica particles induce ROS generation in Langerhans cells

Generation of total intracellular reactive oxygen species (ROS) was measured in XS52 cells, a Langerhans cell-like line, treated with different sized amorphous silica particles. The results suggested that exposure to amorphous nanosilica particles (nSPs) with a particle size of 70 nm induced a higher level of ROS generation than did exposure to micron-sized amorphous silica particles. This finding means that it is essential to examine the biological effects of ROS generated after exposure to nSPs, which will provide useful information for hazard identification as well as the design of safer nanomaterials.

Size-dependent cytotoxic effects of amorphous silica nanoparticles on Langerhans cells

Amorphous silica nanoparticles (nSPs), are widely used in medicines, cosmetics and food. However, due to their reduced particle size they are suspected to pose new risks induced by changes in biological reactivity and kinetics, which differ from those of bulk materials. In a previous study, we showed that silica particles with a diameter of 70 nm penetrated the stratum corneum (SC) of mouse skin and were taken up by living cells such as keratinocytes and Langerhans cells. To clarify the relationship between particle size, distribution and cellular response, we have evaluated size-dependent intracellular localization and cytotoxicity of silica particles, using the mouse epidermal Langerhans cell line XS52. On treatment with silica particles of diameters 70, 300, and 1000 nm, cellular uptake and cytotoxicity increased with reduction in particle size. These results suggest that smaller sized silica particles induced greater cytotoxicity against Langerhans cells, which was correlated with the quantity of particle uptake into the cells.

Generation of anti-tumour effector T cells from naïve T cells by stimulation with dendritic/tumour fusion cells

Tumour-draining lymph node T cells are an excellent source of effector T cells that can be used in adoptive tumour immunotherapy because they have already been sensitized to tumour-associated antigens in vivo. However, such tumour-specific immune cells are not readily obtained from the host due to poor immunogenicity of tumours and reduced host immune responses. One obstacle in implementation of adoptive immunotherapy has been insufficient sensitization and expansion of tumour-specific effector cells. In this study, we aim to improve adoptive immunotherapy by generating anti-tumour effector T cells from naïve T lymphocytes. We attempted to achieve this by harnessing the advantages of dendritic cell (DC)-based anti-cancer vaccine strategies. Electrofusion was routinely employed to produce fusion cells with 30-40% efficiency by using the poorly immunogenic murine B16/F10 cell line, D5 cells, and DC generated from bone marrow cells. CD62L-positive T cells from spleens of naïve mice and the fusion cells were cocultured with a low concentration of IL-2. After 9 days of culture, the antigen-specific T cells were identified with an upregulation of CD25 and CD69 expression and a downregulation of CD62L expression. These cells secreted IFN-gamma upon stimulation with irradiated tumour cells. Moreover, when transferred into mice with 3-day established pulmonary metastases, these cells with coadministration of IL-2 exhibited anti-tumour efficacy. In contrast, naïve T cells cocultured with a mixture of unfused DC and irradiated tumour cells did not exhibit anti-tumour efficacy. Our strategy provides the basis for a new approach in adoptive T cell immunotherapy for cancer.

Projection patterns of lamina VIII commissural neurons in the lumbar spinal cord of the adult cat: an anterograde neural tracing study

This study was designed to characterize the morphology of commissural axons, with the goal of revealing some of the organizing principles of their projections in the lumbosacral cord. Axons were labeled anterogradely with biotinylated-dextran amine which was injected in the left lamina VIII and the adjoining parts of lamina VII in the lumbar segments L5-L6 in seven cats. After 3-4 weeks, commissural axons were well labeled throughout lumbosacral segments L1-S2. After crossing the midline at the injection level, labeled axons traveled rostrally and/or caudally in the contralateral ventral and lateral funiculi giving off multiple axon collaterals. The trajectories of 34 single axons were traced in their entirety from their points of origin to their distal ends. Most of these axons were thin (proximal diameter <3.5 microm) and short (<30 mm), and gave off 6 to 32 axon collaterals at short intercollateral distances (mean <2 mm) in the lumbosacral enlargement. Some thicker axons (diameter >3.5 microm) ascended as far as the thoracic level; these supplied only four to six collaterals at long intercollateral intervals ( approximately 6.5 mm). All of the axons except one projected unilaterally. The axons as a whole terminated throughout the contralateral ventral horn. However, axons that traveled in different parts of the white matter had different characteristic terminal arborizations. The collaterals of axons that traveled in the ventral funiculus terminated preferentially in laminae VII-VIII, while those in the lateral funiculus terminated in lamina IX. Although the collateral branching patterns differed from one axon to another, collaterals arising from a particular axon usually exhibited similar patterns at different rostrocaudal levels. These uniform collateral termination patterns indicate that the morphology of each neuron might be specifically related to its function. This may allow future studies to identify different functional types of commissural neurons on the basis of much less extensive reconstructions.

Relative contribution of Ia inhibitory interneurones to inhibition of feline contralateral motoneurones evoked via commissural interneurones

The aim of the study was to examine to what extent the crossed inhibition of hindlimb lumbar alpha-motoneurones is evoked via interneurones that mediate reciprocal inhibition between flexors and extensors (Ia inhibitory interneurones), and to what extent via other spinal interneurones. The crossed inhibition was evoked by reticulospinal and vestibulospinal tract fibres, stimulated in the contralateral medullary longitudinal fascicle and the lateral vestibular nucleus, respectively, or by group II muscle afferents in the contralateral quadriceps nerve. The components of the IPSPs recorded in motoneurones that were mediated by Ia inhibitory interneurones were identified by their depression following activation of Renshaw cells. Trisynaptic components of IPSPs of reticulospinal and vestibulospinal origin, and polysynaptic (but not trisynaptic) components of IPSPs from group II afferents were found to be depressed in the majority of the motoneurones, while disynaptic components, those due to direct actions of inhibitory commissural interneurones, were not depressed. These results indicate that the coordination of left and right hindlimb movements based on crossed inhibition from reticulospinal and vestibulospinal neurones, depends on the degree of activation of Ia inhibitory interneurones by muscle spindle afferents and on their inhibition by Renshaw cells. Our results also indicate that Ia inhibitory interneurones do not operate as last-order inhibitory interneurones in crossed trisynaptic pathways from group II afferents, even though they mediate inhibition evoked by interneurones in shared polysynaptic pathways of crossed flexor and extensor reflexes coactivated by group II and other high-threshold muscle, skin and joint afferents.

[Early and late results of combined valvular and coronary artery surgery]

A total of 42 patients with combined valvular and coronary artery surgery were examined to analyze risk factors for cardiac related events and late deaths. There were aortic valve disease in 26 patients and mitral valve disease in 16. Preoperatively, 14 patients (33%) had cardiac dysfunction (ejection fraction < or = 40%) and 10 patients (24%) were in New York Heart Association (NYHA) functional class IV. There was no operative death with 96% of early graft patency. There was 8 late deaths during 5.6 years of mean follow up. Actuarial survival rate was 86% and 64% after 5 and 10 years, respectively. Cardiac dysfunction was a significant independent predictor for late death. Cardiac related events occurred in 9 patients. Freedom from cardiac related events was 78% and 59% after 5 and 10 years, respectively. Cardiac dysfunction and mitral valve surgery were significant independent predictors for cardiac related events. Late result of combined mitral and coronary artery surgery was unfavorable in patients with cardiac dysfunction.

[Management for type A acute dissection]

From March 1998 to May 2002, we experienced 46 patients with type A acute dissection (AAD). Fifteen patients managed initially with conservative treatment because of intramular hematoma (IH, n = 10), broad cerebral infarction (n = 3), others (n = 2). One who diagnosed IH at admission progressed to AAD and underwent surgery. However his diagnosis of IH at admission was proved to be misdiagnosis retrospectively. In 8 of the remaining 9 patients, hematoma disappeared during the follow-up of 6 months to 1 year. In patients with broad cerebral infarction, 2 died early after admission and 1 discharged with hemiplegia. Thirty-two patients underwent surgery and 1 with preoperative broad cerebral infarction died 36 days after surgery. In the remaining 31 patients, 30 patients discharged ambulatory.

Medullary reticulospinal tract mediating a generalized motor inhibition in cats: iii. functional organization of spinal interneurons in the lower lumbar segments

The previous report of intracellular recording of hindlimb motoneurons in decerebrate cats [ 511] has suggested that the following mechanisms are involved in a generalized motor inhibition induced by stimulating the medullary reticular formation. First, the motor inhibition, which was prominent in the late latency (30-80 ms), can be ascribed to the inhibitory effects in parallel to motoneurons and to interneuronal transmission in reflex pathways. Second, both a group of interneurons receiving inhibition from flexor reflex afferents and a group of Ib interneurons mediate the late inhibitory effects upon the motoneurons. To substantiate the above mechanisms of motor inhibition we examined the medullary stimulus effects upon intracellular (n=55) and extracellular (n=136) activity of spinal interneurons recorded from the lower lumbar segments (L6-L7). Single pulses or stimulus trains (1-3) pulses, with a duration of 0.2 ms and intensity of 20-50 microA) applied to the medullary nucleus reticularis gigantocellularis evoked a mixture of excitatory and inhibitory effects with early (<20 ms) and late (>30 ms) latencies. The medullary stimulation excited 55 interneurons (28.8%) with a late latency. Thirty-nine of the cells, which included 10 Ib interneurons, were inhibited by volleys in flexor reflex afferents (FRAs). These cells were mainly located in lamina VII of Rexed. On the other hand, the late inhibitory effects were observed in 67 interneurons (35.1%), which included cells mediating reciprocal Ia inhibition, non-reciprocal group I (Ib) inhibition, recurrent inhibition and flexion reflexes. Intracellular recording revealed that the late inhibitory effects were due to inhibitory postsynaptic potentials with a peak latency of about 50 ms and a duration of 50-60 ms. The inhibitory effects were attenuated by volleys in FRAs. Neither excitatory nor inhibitory effects with a late latency were observed in 69 (36.1%) cells which were located in the intermediate region and dorsal horn. These results suggest the presence of a functional organization of the spinal cord with respect to the production of the generalized motor inhibition. Lamina VII interneurons that receive inhibition from volleys in FRAs possibly mediate the postsynaptic inhibition from the medullary reticular formation in parallel to motoneurons and to interneurons in reflex pathways.

Slowly developing perigraft seroma after a modified Blalock-Taussig shunt

We report a 26-year-old patient with slowly developing perigraft seroma 15 years after a modified Blalock-Taussig shunt with an expanded polytetrafluorethylene graft. The mediastinal mass was first observed on a chest x-ray film 8 years after the shunt operation. The mass contained massive gelatinous or organic tissues with a severely calcified pseudocapsule, and it was adjacent to the calcified but functioning graft. No fluid collections were noted. The histological findings were compatible with a seroma. No recurrence was noted on last follow-up 1 year postoperatively.

Postoperative evaluation of pylorus-preserving procedures compared with conventional distal gastrectomy for early gastric cancer

We evaluated postoperative function in 98 patients who underwent surgery for early gastric cancer between 1995 and 1998 to compare the results of pylorus-preserving procedures to those of conventional distal gastrectomy with Billroth I (B-I). The pylorus-preserving procedures included endoscopic mucosal resection (EMR), performed in 12 patients; local resection (Local), performed in 14 patients; segmental resection (Seg), performed in 8 patients; and pylorus-preserving gastrectomy (PPG), performed in 19 patients. B-I was performed in 45 patients. The nutritional status and serum albumin (Alb) levels after PPG, the hemoglobin (Hb) levels after EMR, Local, and PPG, and the present/preoperative body weight ratios after EMR, Local, Seg, and PPG were superior to those after B-I. The time before oral intake was recommenced after EMR and Local, the volume of oral intake tolerated after EMR, Local, Seg, and PPG, and the postoperative hospital stay after EMR were all superior to those after B-I. Moreover, significantly fewer patients suffered reflux symptoms after EMR, Local, and PPG, abdominal fullness after EMR, and early dumping syndrome after EMR, Local, and PPG than after B-I. There was also less evidence of gastritis after EMR, Local, and PPG, and of bile reflux after EMR, Local, and PPG, than after B-I. These findings indicate that pylorus-preserving procedures may result in a better postoperative quality of life for selected patients with early gastric cancer.

[Emergent surgical treatment of type A acute aortic dissection in an elderly patient]

An 86-year-old man with severe chest pain and shock was transferred to our hospital. Computed tomography revealed type A aortic dissection with cardiac tamponade. He needed intubation and closed chest massage preoperatively. At operation, intrapericardial space was filled with clotted blood and rupture of the ascending aorta was confirmed. He underwent a successful emergency graft replacement of the ascending aorta. Postoperative course was uneventful except for mild hemianopsia due to cerebral infarction. He had recovered to be able to walk and is doing well.

Environmentally benign formation of polymeric microspheres by rapid expansion of supercritical carbon dioxide solution with a nonsolvent

A novel method is reported for forming polymer microparticles, which reduce atmospheric emissions of environmentally harmful volatile organic compounds such as toluene and xylene used as paint solvent in paint industry. The polymer microparticles have formed through rapid expansion from supercritical solution with a nonsolvent (RESS-N). Solubilization of poly(styrene)-b-(poly(methyl methacrylate)-co-poly (glycidyl methacrylate)) copolymer(PS-b-(PMMA-co-PGMA), MW = 5000, PS/PMMA/PGMA = 2/5/3), poly(ethylene glycol) (PEG, M. W = 4000), bisphenol A type epoxy resin (EP, MW = 3000), poly(methyl methacrylate) (PMMA; MW = 15000, 75000, 120000), and poly(oxyalkylene) alkylphenyl ether (MW = 4000) in carbon dioxide (CO2) was achieved with the use of small alcohols as cosolvents. The solubility of the PS-b-(PMMA-co-PGMA) is extremely low in either CO2 or ethanol but becomes 20 wt % in a mixture of the two. Because ethanol is a nonsolvent for the polymer, it can be used as a cosolvent in rapid expansion from supercritical solution to produce 1-3 microm particles that do not agglomerate. Obtained polymer particles by RESS-N were applied as powder coatings. The resulting coatings have a smooth and coherent film. The particle size distribution of microspheres was controlled by changing the polymer concentration, preexpansion pressure, temperature, and injection distance. The feed compositions were more effective than the other factors in controlling the particle size. The polymeric microparticles formed by RESS-N method can be utilized to make the thin coating film without anytoxic organic solvents and/or surfactants.

A new method for evaluating the bitterness of medicines by semi-continuous measurement of adsorption using a taste sensor

We describe a new method for the evaluation of the bitterness of medicines by semi-continuous measurement of adsorption using a multichannel taste sensor or 'electric tongue'. The bitterness of 10 basic medicines was evaluated by both the taste sensor and in human gustatory sensation tests with 11 volunteers. The sensor part of the taste sensor consists of eight electrodes made of lipid/polymer membranes. Three variables were obtained from the taste sensor data: sensor output (S), the change of membrane potential caused by adsorption, corresponding to aftertaste (C), and the ratio C/S. These variables were used to predict an estimated bitterness score in multiple regression analysis. Semi-continuous measurement of C (every 30 s up to 150 s) was adopted as an additional explanatory variable, and the attenuation rate of C was defined as C'. These data were also subjected to multiple regression analysis. The correlation coefficient (r) estimated for the bitterness score predicted by the taste sensor, using C' for channel 2 and C/S for channel 4, and the score obtained by human gustatory sensation, was 0.824. This value was greater than that obtained using C/S for both channels 2 and 4 (0.734). The method described in the present study seems to offer good predictability for the evaluation of bitterness.

Preparation and characterization of insulin-loaded acrylic hydrogels containing absorption enhancers

The objectives of this study were to prepare insulin-loaded acrylic hydrogel formulations containing various absorption enhancers, to perform in vitro and in vivo characterization of these formulations, and to evaluate the factors which affecting insulin availability on rectal delivery of insulin using this hydrogel system. The acrylic block copolymer of methacrylic acid and methacrylate, Eudispert, was used to make the hydrogel formulations. As absorption enhancers, 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-CyD), lauric acid (C12), or the sodium salt of C12 (C12Na), were incorporated into the hydrogels. In an in vitro release test, the release rate of insulin from the hydrogels decreased as the polymer concentration of the hydrogel increased. The addition of C12Na to the hydrogel further increased the insulin release rate, which was greater at higher concentrations of the enhancer. A portion of the C12Na was found to remain bound to the acrylic polymer in dissolution medium. Serum insulin levels were determined at various time points after the administration of insulin solution or insulin-loaded (50 units/kg body weight) Eudispert hydrogels containing 5% (w/w) of C12, C12Na, or DM-beta-CyD to in situ loops in various regions of the rat intestine. The most effective enhancement of insulin release was observed with formulations containing C12Na. The bioavailability of insulin from the hydrogels was lower than that from the insulin solutions. Hydrogel formulations containing 7% or 10% Eudispert remained in the rectum for 5 h after rectal administration. However, the 5% (w/w) C12Na solution stained with Evan's-blue had diffused out and the dye had reached the upper intestinal tract within 2 h. Finally, the rectal administration of insulin-loaded hydrogels, containing 4%, 7%, or 10% (w/w) Eudispert and 5% (w/w) of enhancer (C12, C12Na, or DM-beta-CyD) to normal rats was shown to decrease serum glucose concentrations. The greatest effect was found with insulin-loaded 7% (Eudispert) hydrogel containing C12Na which having cosiderable large insulin release rate and bioadhesive characteristics.

Pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation

Right atrial isomerism is well known to be associated with anomalous pulmonary venous drainage and a potentially dangerous sequel to pulmonary venous obstruction, and is associated with high mortality. We report a 16-month-old girl with pulmonary venous obstruction requiring lobectomy for hemoptysis after a Glenn operation. Two years after surgery, she is doing well with 80% oxygen saturation and no further episodes of hemoptysis.

Early and late results of partial plication annuloplasty for congenital mitral insufficiency

BACKGROUND

Partial plication annuloplasty is the main technique for congenital mitral insufficiency because this technique allows the mitral anulus to grow, in contrast to ring annuloplasty. However, this technique is not satisfactory for mitral insufficiency with some anomalies of the mitral valve apparatus.

METHODS

Forty-one patients underwent partial plication annuloplasty for mitral regurgitation from July 1979 to December 1998. Mitral regurgitation associated with an atrioventricular defect, an atrioventricular discordance, and a univentricular heart was excluded from this study.

RESULTS

There were no early or late deaths. In early results, partial plication annuloplasty was more effective for mitral regurgitation with abnormality of the posterior leaflet (n = 14) or normal leaflet motion (n = 8) than with abnormality of the anterior leaflet and its apparatus (n = 14) or absence of chordae (n = 4). The mean follow-up period was 145.8 months. During the follow-up period, 2 patients underwent mitral valve replacement, and a third patient underwent mitral valve repair with partial plication annuloplasty after the first repair. The main cause of mitral regurgitation of 2 of the 3 patients was absence of chordae. The actuarial freedom from reoperation rate was 94.9% +/- 3.6%, 91.9% +/- 4.7%, and 91.9% +/- 4.7% at 5, 10, and 15 years after the operation, respectively.

CONCLUSION

Early and long-term results of partial plication annuloplasty were acceptable for congenital mitral insufficiency with any type of malformation of the mitral valve, and results were excellent with abnormality of the posterior leaflet and its apparatus or normal leaflet motion. However, late results were suboptimal for mitral regurgitation with absence of chordae. Other techniques, such as artificial chorda replacement, should be adapted in these cases.

De Vega annuloplasty and Carpentier-Edwards ring annuloplasty for secondary tricuspid regurgitation

BACKGROUND AND AIM OF THE STUDY

Residual or recurrent tricuspid regurgitation (TR) has been reported after several types of surgical repair. The development of late TR is an important complication of left heart surgery. The results of De Vega annuloplasty were compared with those obtained after Carpentier-Edwards ring (CE ring) annuloplasty in patients with secondary TR.

METHODS

The records of 45 patients who underwent surgery for secondary TR between January 1995 and July 2000 were reviewed retrospectively. Twenty-eight patients underwent De Vega annuloplasty, and 17 had a CE ring annuloplasty. The groups were similar with respect to associated cardiac lesions. No significant preoperative differences were observed in NYHA functional class, TR grade, and pulmonary artery pressure between the two groups.

RESULTS

One CE patient died of left ventricular dysfunction after postoperative bleeding. The 28 De Vega patients and remaining 16 CE patients had an uneventful recovery, and were discharged. Tricuspid ring size after repair was similar between groups. Mean (+/- SD) follow up in the entire patient cohort was 39+/-23 months (range: 6 to 75 months). TR recurrence was rated as grade II or III in 13 patients (45%) after De Vega annuloplasty, but was grade II or III in only one patient (6%) patient after CE ring annuloplasty. There was a significant difference in TR recurrence between the groups (p = 0.027), but no significant difference in NYHA class.

CONCLUSION

CE ring annuloplasty significantly decreased the recurrence of TR; thus, CE ring annuloplasty is superior to De Vega annuloplasty in patients with secondary TR.

Hyperamylasemia and subclinical pancreatitis after cardiac surgery

Hyperamylasemia after cardiac surgery is common but typically causes no clinical concern because it consists mainly of the salivary isoenzyme. In this study we evaluated the incidence, source, and time course of postoperative hyperamylasemia with special attention to the possibility of subclinical pancreatitis. In 88 patients prospectively tested for serum amylase and lipase concentrations, elastase 1 activity, and amylase isoenzyme characteristics, 57 (64%) showed hyperamylasemia during the early postoperative period. In most cases early hyperamylasemia was not of pancreatic origin, but two patients were diagnosed with subclinical pancreatitis. Among the last 23 patients, 5 of 10 patients with early hyperamylasemia exceeding 1000 IU/L showed late hyperamylasemia on the seventh postoperative day, when it represented mainly the pancreatic isoenzyme. Lipase concentrations and elastase 1 activities were elevated in these cases. Late hyperamylasemia following cardiac surgery may be of pancreatic origin and indicative of subclinical pancreatitis, even if early hyperamylasemia was of salivary origin.

Medullary reticulospinal tract mediating the generalized motor inhibition in cats: parallel inhibitory mechanisms acting on motoneurons and on interneuronal transmission in reflex pathways

The present study was designed to elucidate the spinal interneuronal mechanisms of motor inhibition evoked by stimulating the medullary reticular formation. Two questions were addressed. First, whether there is a parallel motor inhibition to motoneurons and to interneurons in reflex pathways. Second, whether the inhibition is mediated by interneurons interposed in known reflex pathways. We recorded the intracellular activity of hindlimb motoneurons in decerebrate cats and examined the effects of medullary stimulation on these neurons and on interneuronal transmission in reflex pathways to them. Stimuli (three pulses at 10-60microA and 1-10ms intervals) delivered to the nucleus reticularis gigantocellularis evoked inhibitory postsynaptic potentials in alpha-motoneurons (n=147) and gamma-motoneurons (n=5) with both early and late latencies. The early inhibitory postsynaptic potentials were observed in 66.4% of the motoneurons and had a latency of 4.0-5.5ms with a segmental delay of more than 1.4ms. The late inhibitory postsynaptic potentials were observed in 98.0% of the motoneurons and had a latency of 30-35ms, with a peak latency of 50-60ms. Both types of inhibitory postsynaptic potentials were evoked through fibers descending in the ventrolateral quadrant. The inhibitory postsynaptic potentials were not influenced by recurrent inhibitory pathways, but both types were greatly attenuated by volleys in flexor reflex afferents. Conditioning medullary stimulation, which was subthreshold to evoke inhibitory postsynaptic potentials in the motoneurons, neither evoked primary afferent depolarization of dorsal roots nor reduced the input resistance of the motoneurons. However, the conditioning stimulation often facilitated non-reciprocal group I inhibitory pathways (Ib inhibitory pathways) to the motoneurons in early (<20ms) and late (30-80ms) periods. In contrast, it attenuated test postsynaptic potentials evoked through reciprocal Ia inhibitory pathways, and excitatory and inhibitory pathways from flexor reflex afferent and recurrent inhibitory pathways. The inhibitory effects were observed in both early and late periods. The present results provide new information about a parallel inhibitory process from the medullary reticular formation that produces a generalized motor inhibition by acting on alpha- and gamma-motoneurons, and on interneurons in reflex pathways. Interneurons receiving inhibition from flexor reflex afferents and a group of Ib interneurons may mediate the inhibitory effects upon motoneurons.

Coronary artery bypass grafting for patients with an atherosclerotic ascending aorta

OBJECTIVES

We review the outcome of coronary artery bypass grafting in patients with a severe atherosclerotic ascending aorta.

METHODS

Subjects were 31 patients averaging 69.4 +/- 6.9 years old studied from 1990 through 1998. Ascending aortic lesions were assessed using epiaortic echo and 2 types of aortic nonclamping techniques applied. In 29 patients operated on in the early years, bypass grafting was conducted on the hypothermic fibrillated heart in 22 and on the beating heart in 7. The remaining 2 underwent off-pump coronary artery bypass grafting more recently. For cases with multivessel disease, we used composite grafting.

RESULTS

Three patients developed mild stroke and 5 died within 30 days of surgery--4 from multiple emboli (1 accompanied by a stroke) and 1 from perioperative myocardial infarction. One hospital death occurred due to brain damage and multiorgan failure following unexpected rupture of a saphenous vein graft. No cardiac deaths occurred in the late stage of our series. Actuarial survival was 73.0% for 3 years and 68.0% for 5 years. Freedom from cardiac events was favorable in the remaining 25 survivors.

CONCLUSIONS

Outcome was suboptimal for the risks involved. Recent technical advances, including coronary surgery on the beating heart with or without cardiopulmonary bypass using variable in-situ or free arterial grafts, associated with adequate evaluation of systemic atherosclerosis, should improve this outcome.

Pioglitazone, a specific PPAR-gamma ligand, inhibits aspirin-induced gastric mucosal injury in rats

BACKGROUND

Neutrophils activation and tumour necrosis factor-alpha (TNF-alpha) induction play a critical role in aspirin-induced gastric mucosal injury. Peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, has recently been implicated as a regulator of inflammatory responses. The aim of the present study was to determine whether pioglitazone, a specific PPAR-gamma ligand, can ameliorate aspirin-induced gastric mucosal injury in rats, and whether the agent can inhibit the increase in neutrophil accumulation associated with TNF-alpha expression.

METHODS

Aspirin-induced injury was produced by the intragastric administration of aspirin (200 mg/kg) and HCl (0.15 N, 8.0 mL/kg). Pioglitazone was given to the rats by gastric intubation 1 h before the aspirin administration. Thiobarbituric acid-reactive substances and tissue-associated myeloperoxidase activity were measured in gastric mucosa as indices of lipid peroxidation and neutrophil infiltration. The gastric concentration of TNF-alpha and the expression of TNF-alpha mRNA was determined by ELISA and reverse transcriptase-polymerase chain reaction.

RESULTS

The intragastric administration of acidified aspirin induced hyperemia and haemorrhagic erosions in rat stomachs. The increase in the total gastric erosive area after aspirin administration was significantly inhibited by treatment with pioglitazone in a dose-dependent manner. The increases in thiobarbituric acid-reactive substances and myeloperoxidase activity after aspirin administration were both significantly inhibited by pre-treatment with pioglitazone (10 mg/kg). The gastric content of TNF-alpha increased and the expression of TNF-alpha mRNA was up-regulated after aspirin treatment. However, the peak TNF-alpha mRNA expression 1 h after aspirin administration was inhibited by pioglitazone.

CONCLUSION

Based on these data, the beneficial effects of pioglitazone on aspirin-induced gastric mucosal injury may be attributed to its anti-inflammatory properties.

Clinical characteristics of patients with constrictive pericarditis after coronary bypass surgery

Constrictive pericarditis (CP) is an unusual sequela of cardiac surgery, so the present study evaluated the clinical characteristics of patients with CP after coronary artery bypass grafting (CABG). Four hundred and sixty-three patients who underwent isolated CABG between January 1989 and March 1999 were examined retrospectively. The first choice of treatment for postoperative pericardial effusion was non-steroid anti-inflammatory agents, and an increased dose of diuretics. The second treatment choice was corticosteroids or pericardial drainage. When CP was suspected during the follow-up period (mean, 54+/-31 months), cardiac catheterization was carried out to establish the diagnosis. Of the 463 patients undergoing CABG, there were 11 (2.4%) who developed CP after surgery. The median time to the onset of symptoms after CABG was 4 weeks (range, 3-96 weeks). On univariate and multivariate analysis, normal left ventricular ejection fraction, warfarin administration, and early postoperative pericardial effusion were significantly associated with a greater potential of postoperative CP. The effusion was bloody in all cases of pericardial drainage despite warfarin therapy. Not draining the postoperative effusive pericardial effusion was a risk factor for the development of CP. Pericardial drainage for patients with significant effusion after CABG is important for the prevention of subsequent CP, especially in those patients being treated with warfarin or with normal left ventricular function.

Surgery for acute type A aortic dissection using retrograde cerebral perfusion

OBJECTIVE

We reviewed the surgical management of acute type A aortic dissection between 1989 and 1998.

METHODS

Subjects were 28 consecutive patients (mean age: 61.8 +/- 10.7 years) with acute type A aortic dissection were studied. The mean duration between aortic dissection onset and surgery was 17.5 +/- 17.0 hours. In surgery, aortic pathology and flow patterns in dissected aortic channels were evaluated using transesophageal and epiaortic echo. Simple, safe combination of profound hypothermic circulatory arrest with retrograde cerebral perfusion and open aortic anastomosis was used for brain protection. Hypothermic circulatory arrest was 46.9 +/- 24.8 minutes. Aortic repair consisted in ascending aortic replacement in 5 patients, with hemiarch repair in 17, and total arch repair in 6. Intimal tears were resected in all but 2 patients. Concomitantly resuspension of the aortic valve was done in 9 and aortic root replacement in 2.

RESULTS

No operative (30-day) deaths occurred, although 2 died from unrelated hepatic failure during hospitalization or late-stage pancreatic cancer in the late stage. In cerebral sequellae, 1 patient suffered a stroke and 2 patients developed temporary neurologic dysfunction.

CONCLUSION

Our experience demonstrated that the simplified conjunction of hypothermic circulatory arrest with retrograde cerebral perfusion and open aortic anastomosis, associated with real-time assessment by transesophageal and epiaortic echo, is safe and useful during emergency aortic repair for acute type A aortic dissection.

Variation of des-gamma-carboxyprothrombin (PIVKA-II) levels in cord blood throughout gestation

The variation of des-gamma-carboxyprothrombin (PIVKA-II, protein induced by vitamin K absence) levels in umbilical cord blood throughout gestation was examined using a highly sensitive method, electrochemiluminescence immunoassay (ECLIA). PIVKA-II levels in infants without any complications were low, but modestly high, exceeding the normal range of healthy adults during the preterm period, followed by a remarkable increase after the 37th week of gestation. Among infants complicated with severe preeclampsia a marked increase of PIVKA-II levels was observed in preterm infants, showing a good correlation with the existence ofinfarctions on the placenta. On the other hand, among infants complicated with preterm premature rupture of the membranes (PROM) in which antibiotics were administered during the prenatal period, a moderate elevation of PIVKA-II levels was observed. These data suggest that the normal range of PIVKA-II in fetuses is modestly high compared with adults and any deficient status of vitamin K would not exist throughout the preterm period. Nevertheless, the vitamin K status might readily fall into a deficient condition in term infants. Furthermore, it is notable that vitamin K deficiency would be induced in complicated gestation with severe preeclampsia and medication with antibiotics.