Effect of propofol on norepinephrine-induced increases in [Ca2+]i and force in smooth muscle of the rabbit mesenteric resistance artery

BACKGROUND

Propofol (2,6-diisopropylphenol) possesses vasodilating activity in vivo and in vitro. The propofol-induced relaxation of agonist-induced contractions in small resistance arteries has not been clarified.

METHODS

The effect of propofol was examined on the contractions induced by norepinephrine and high K+ in endothelium-denuded rabbit mesenteric resistance artery in vitro. The effects of propofol on the [Ca2+]i mobilization induced by norepinephrine and high K+ were studied by simultaneous measurement of [Ca2+]i using Fura 2 and isometric force in ryanodine-treated strips.

RESULTS

Propofol attenuated the contractions induced by high K+ and norepinephrine, the effect being greater on the high K+-induced contraction than on the norepinephrine-induced contraction. In Ca2+-free solution, norepinephrine produced a transient contraction resulting from the release of Ca2+ from storage sites that propofol attenuated. In ryanodine-treated strips, propofol increased the resting [Ca2+]i but attenuated the increases in [Ca2+]i and force induced by both high K+ and norepinephrine. In the presence of nicardipine, propofol had no inhibitory action on the residual norepinephrine-induced [Ca2+]i increase, whereas it still modestly increased resting [Ca2+]i, as in the absence of nicardipine.

CONCLUSIONS

In smooth muscle of the rabbit mesenteric resistance artery, propofol attenuates norepinephrine-induced contractions due to an inhibition both of Ca2+ release and of Ca2+ influx through L-type Ca2+ channels. Propofol also increased resting [Ca2+]i, possibly as a result of an inhibition of [Ca2+]i removal mechanisms. These results may explain in part the variety of actions seen with propofol in various types of vascular smooth muscle.

Cortical anesthesia reduced the amplitude of local P300 event-related potential in rabbits by auditory oddball paradigm

Eight rabbits were employed in this study. Under anesthesia, one electrode was fixed in the skull at the bregma and another was fixed, with three guide cannulas around it, at a parietal point 5 mm lateral to the bregma. Two weeks later, with a 10-day interval, either 0.5% lidocaine (9 microl) or the same volume of normal saline was injected into cortex through the cannulas. Event-related potentials (ERPs) evoked by auditory oddball paradigm were recorded before and after the injections in alert rabbits. The probability of occurrence for the 2 and 1 kHz stimulus tones was 90% (frequent) and 10% (rare), respectively. After lidocaine injection, P3 amplitude to rare stimuli decreased to 37.6% (P < 0.05), while N1 did not show any significant changes. ERPs from the bregma were intact. P3 and N1 did not change after normal saline injection. Our results show that local parietal cortex is one of the P3 generators.

Use of leukocyte depletion to decrease injury after lung preservation and rewarming ischemia: an experimental model

BACKGROUND

Hypothermia is critical for proper lung preservation. Ideally, the lungs should be maintained at the optimal preservation temperature during the entire ischemic interval. Lung rewarming during implantation is commonly observed. This study was undertaken to investigate the severity of rewarming ischemia on preservation injury and the possibility of minimizing this by use of leukocyte depletion during initial reperfusion.

METHODS

Four experimental groups were tested as follows: neonatal piglet heart-lung blocks were either (1) placed on an isolated, blood-perfused, working heart-lung circuit without intervening ischemia (control, n = 6), (2) reperfused on the circuit with whole blood (WB, n = 6) after 13 hours of preservation, (3) reperfused with WB after 12 hours of preservation and 1 hour of rewarming (RWB, n = 5), or (4) reperfused with leukocyte-depleted blood for an initial 10 minutes followed by WB, after 12 hours of preservation and 1 hour of rewarming (n = 6). All groups were studied for 4 hours.

RESULTS

The partial pressure of arterial oxygen and lung compliance were significantly lower in the RWB group than in controls (113.8+/-33.1 vs 417.3+/-6.2 mm Hg, p < 0.01; and 0.8+/-0.2 vs 2.9+/-0.4 ml/cm H2O, p < 0.05, respectively). Pulmonary vascular resistance and lung wet/dry weight ratios were significantly higher in the RWB group than in controls (15884.1+/-11354.8 vs 6108.3+/-1309.9 dyne x sec x cm[-5], p < 0.05; and 7.13+/-0.24 vs 5.82+/-0.35, p < 0.05, respectively). The WB and leukocyte-depleted groups did not differ significantly from controls for any measured parameter.

CONCLUSIONS

This model confirms that rewarming ischemia during lung implantation exacerbates reperfusion injury. Leukocyte-depleted reperfusion as tested for a short period of time (10 minutes) ameliorates this injury and therefore should be considered for clinical lung transplantation.

Effect of cilostazol, a phosphodiesterase type III inhibitor, on histamine-induced increase in [Ca2+]i and force in middle cerebral artery of the rabbit

1. The effect of cilostazol, an inhibitor of phosphodiesterase type III (PDE III), on the contraction induced by histamine was studied by making simultaneous measurements of isometric force and the intracellular concentration of Ca2+ ([Ca2+]i) in endothelium-denuded muscle strips from the peripheral part of the middle cerebral artery of the rabbit. 2. High K+ (80 mM) produced a phasic, followed by a tonic increase in both [Ca2+]i and force. Cilostazol (10 microM) did not modify the resting [Ca2+]i, but it did significantly decrease the tonic contraction induced by high K+ without a corresponding change in the [Ca2+]i response. 3. Histamine (3 microM) produced a phasic, followed by a tonic increase in both [Ca2+]i and force. Cilostazol (3 and 10 microM) significantly reduced both the phasic and tonic increases in [Ca2+]i and force induced by histamine, in a concentration-dependent manner. 4. Rp-adenosine-3':5'-cyclic monophosphorothioate (Rp-cAMPS, 0.1 mM), a PDE-resistant inhibitor of protein kinase A (and as such a cyclic AMP antagonist), did not modify the increases in [Ca2+]i and force induced by histamine alone, but it did significantly decrease the cilostazol-induced inhibition of the histamine-induced responses. 5. In Ca2+-free solution containing 2 mM EGTA, both histamine (3 microM) and caffeine (10 mM) transiently increased [Ca2+]i and force. Cilostazol (1-10 microM) (i) significantly reduced the increases in [Ca2+]i and force induced by histamine, and (ii) significantly reduced the increase in force but not the increase in [Ca2+]i induced by caffeine. 6. In ryanodine-treated strips, which had functionally lost the histamine-sensitive Ca2+ storage sites, histamine (3 microM) slowly increased [Ca2+]i and force. Cilostazol (3 and 10 microM) lowered the resting [Ca2+]i, but did not modify the histamine-induced increase in [Ca2+]i, suggesting that functional Ca2+ storage sites are required for the cilostazol-induced inhibition of histamine-induced Ca2+ mobilization. 7. The [Ca2+]i-force relationship was obtained in ryanodine-treated strips by applying ascending concentrations of Ca2+ (0.16-2.6 mM) in Ca2+-free solution containing 100 mM K+. Histamine (3 microM) shifted the [Ca2+]i-force relationship to the left and increased the maximum Ca2+-induced force. Under the same conditions, whether in the presence or absence of 3 microM histamine, cilostazol (3-10 microM) shifted the [Ca2+]i-force relationship to the right without producing a change in the maximum Ca2+-induced force. 8. It is concluded that, in smooth muscle of the peripheral part of the rabbit middle cerebral artery, cilostazol attenuates the histamine-induced contraction both by inhibiting histamine-induced Ca2+ mobilization and by reducing the myofilament Ca2+ sensitivity. It is suggested that the increase in the cellular concentration of cyclic AMP that will follow the inhibition of PDE III may play an important role in the cilostazol-induced inhibition of the histamine-contraction.

[Anesthetic management of a patient with antiphospholipid syndrome]

A 46-year-old woman with antiphospholipid syndrome (APS) underwent an emergent laparotomy. The symptoms and signs of APS are reported to be thrombosis, habitual abortion, thrombocytopenia and biological false positive (BFP) for syphilis' tests. Clinical symptoms are based on hypercoagulation of blood, while prothrombin time (PT) activity and activated partial thromboplastin time (APTT) are prolonged. Although we have selected general endotracheal anesthesia without epidural catheterization, we recommend that the regional analgesia is suitable for those APS patients with abnormality of coagulation. If PT and APTT differ from clinical symptoms, we have to think about APS and manage the patients carefully as APS.

Vaginal atresia with transverse septum in a cat

A six and half-year-old nulliparous mixed breed cat which had the complaints of vomiting, abdominal distention and depression was presented to the Veterinary Teaching Hospital of Osaka Prefecture University. She was suspected of pyometra by clinical signs and tests. By laparotomy, it was clarified that both uterine horns and vagina showed distension by the accumulation of secretions, and the vagina ended blindly leaving a tough connective tissue at the border between cranial and caudal part of the vagina. Postoperative contrast-radiograph of the remaining vagina proved it had no persistence of the hymen. From these findings, the condition was diagnosed as a feline atresia vaginalis with the transverse vaginal septum which is caused by the embryonic failure of canalization of the paramesonephric duct between the end of the Müllerian duct and the urogenital sinus.

Purification and characterization of a GroEL homologue from the moderately eubacterial halophile Pseudomonas sp. #43

We have purified to apparent homogeneity and characterized a molecular chaperonin GroEL homologue (hpGroEL) from a moderately halophilic eubacterium, Pseudomonas sp. #43. Although this halophilic bacterium requires 1-2 M NaCl for growth, hpGroEL did not require a high concentration of salt for its stability, ATPase activity and refold-promoting activity for denatured protein. The ATPase activity was even more halo-sensitive than that of GroEL from Escherichia coli. The hpGroEL protein promotes Mg(2+)-ATP-dependent refolding of urea-denatured alpha-glucosidase in the presence of E. coli-GroES, indicating that chaperonins 60 and 10 isolated from halophilic and nonhalophilic eubacteria, respectively, can cooperate with each other.

Retrieval by other procurement teams provides favorable lung transplantation outcome

BACKGROUND

During the last 4 years, we have increasingly used lungs retrieved by other procurement teams. We therefore investigated whether the use of those lungs affected the outcome of lung transplantation.

METHODS

We analyzed the results of 159 consecutive lung transplantations performed at our institution between July 1, 1992, and December 31, 1995. The transplants were divided into three groups: distant donor lungs retrieved by our team (DB group, n = 68); distant donor lungs retrieved by other teams (DX group, n = 46); and local donor lungs retrieved by our team (LB group, n = 44). One transplantation with a local donor lung retrieved by another team was excluded from the analysis.

RESULTS

No significant differences were noted between the three groups in alveolar-arterial oxygen gradient immediately after transplantation (DB group, 359 +/- 18 mm Hg; DX group, 329 +/- 23 mm Hg; LB group, 327 +/- 20 mm Hg) and at 24 hours; days on ventilator; days in the intensive care unit; length of hospital stay; 30-day mortality; and actuarial 1-year survival (DB group, 81%; DX group, 87%; LB group, 89%).

CONCLUSIONS

The use of donor lungs retrieved by other teams achieves an equivalently satisfactory outcome after lung transplantation as lungs retrieved by our team.

Possible mechanisms underlying the midazolam-induced relaxation of the noradrenaline-contraction in rabbit mesenteric resistance artery

1. The mechanisms underlying the midazolam-induced relaxation of the noradrenaline (NA)-contraction were studied by measuring membrane potential, isometric force and intracellular concentration of Ca2+ ([Ca2+]i) in endothelium-denuded muscle strips from the rabbit mesenteric resistance artery. The actions of midazolam were compared with those of nicardipine, an L-type Ca2+-channel blocker. 2. Midazolam (30 and 100 microM) did not modify either the resting membrane potential or the membrane depolarization induced by 10 microM NA. 3. NA (10 microM) produced a phasic, followed by a tonic increase in both [Ca2+]i and force. Midazolam (10-100 microM) did not modify the resting [Ca2+]i, but attenuated the NA-induced phasic and tonic increases in [Ca2+]i and force, in a concentration-dependent manner. In contrast, nicardipine (0.3 microM) attenuated the NA-induced tonic, but not phasic, increases in [Ca2+]i and force. 4. In Ca2+-free solution containing 2 mM EGTA, NA (10 microM) transiently increased [Ca2+]i and force. Midazolam (10-100 microM), but not nicardipine (0.3 microM), attenuated this NA-induced increase in [Ca2+]i and force, in a concentration-dependent manner. However, midazolam (10 and 30 microM), had no effect on the increases in [Ca2+]i and force induced by 10 mM caffeine. 5. In ryanodine-treated strips, which have functionally lost the NA-sensitive Ca2+ storage sites, NA slowly increased [Ca2+]i and force. Nicardipine (0.3 microM) did not modify the resting [Ca2+]i but partly attenuated the NA-induced increases in [Ca2+]i and force. In the presence of nicardipine, midazolam (100 microM) lowered the resting [Ca2+]i and further attenuated the remaining NA-induced increases in [Ca2+]i and force. 6. The [Ca2+]i-force relationship was obtained in ryanodine-treated strips by the application of ascending concentrations of Ca2+ (0.16-2.6 mM) in Ca2+-free solution containing 100 mM K+. NA (10 microM) shifted the [Ca2+]i-force relationship to the left and enhanced the maximum Ca2+-induced force. Under these conditions, whether in the presence or absence of 10 microM NA, midazolam (10 and 30 microM) attenuated the increases in [Ca2+]i and force induced by Ca2+ without changing the [Ca2+]i-force relationship. 7. It was concluded that, in smooth muscle of the rabbit mesenteric resistance artery, midazolam inhibits the NA-induced contraction through its inhibitory action on NA-induced Ca2+ mobilization. Midazolam attenuates NA-induced Ca2+ influx via its inhibition of both nicardipine-sensitive and -insensitive pathways. Furthermore, midazolam attenuates the NA-induced release of Ca2+ from the storage sites. This effect contributes to the midazolam-induced inhibition of the NA-induced phasic contraction.

[Acute retrograde dissection of the aorta is a formidable complication in retrograde perfusion through the femoral artery]

To avoid this complication, we applied a Nelaton catheter (Imamura, Tokyo, Japan: standard type) as a guide to insert an arterial perfusion cannula (Bardic) into the femoral artery. Initially, the Nelaton catheter is accurately placed into the femoral artery through a purse string suture without applying vascular clamps on the artery or its branches. Then the perfusion cannula is advanced using the Nelaton catheter as a guide. We believe this procedure will avoid acute retrograde dissection of the aorta since it protects the femoral artery from injuries caused by the vascular clamps or the tip of the perfusion cannula.

Peritoneal lymphatic stomata of the diaphragm in the mouse: process of their formation

BACKGROUND

Lymphatic stomata are channels connecting the peritoneal cavity with the lymphatics in the diaphragm. The process of sequential formation of the stomata has not been studied. The objective of this study was to examine the morphogenesis of the lymphatic stomata in mice.

METHODS

Ultrathin sections of diaphragms from ddY mice obtained on embryonic day 18 and postnatal days 0, 4, and 10 were observed with a transmission electron microscope.

RESULTS

By embryonic day 18 and postnatal day 0, lymphatics were already observed in the submesothelial connective tissue on the peritoneal side of the fetal diaphragm. The lymphatic endothelial cells, but not the mesothelial cells covering the diaphragm, protruded short cytoplasmic processes into the submesothelial connective tissue, and these almost reached the basal surfaces of individual mesothelial cells. By postnatal days 4 and 10, the lymphatic endothelial cells frequently protruded cytoplasmic processes into the submesothelial connective tissue, and the endothelial cell processes broke the continuity of both the basal lamina beneath the mesothelial cells and the submesothelial connective tissue. Neighboring endothelial processes formed a pair of U-shaped folds that were connected with each other via intercellular junctions at the apexes of the U-shaped folds. The disassembly of the intercellular junctions between the U-shaped folds was observed, and the basal surface of the mesothelial cell faced the lymphatic lumen. Dehiscence of the intercellular junctions between the mesothelial cells overlaying the lymphatics was observed, and lymphatic stomata were present. On the pleural side of the diaphragm, lymphatics were already present on embryonic day 18, but it was not observed that the endothelial process spanned the submesothelial connective tissue to the basal surface of the mesothelial cell.

CONCLUSIONS

These results suggest the following process of the formation of the lymphatic stomata. (1) Neighboring lymphatic endothelial cells span the submesothelial connective tissue to the basal surfaces of mesothelial cells. (2) The lymphatic stomata are formed by the disassembly of the intercellular junctions between the neighboring endothelial cells and between the mesothelial cells overlying the endothelial cells.

P300-like potential disappears in rabbits with lesions in the nucleus basalis of Meynert

The nucleus basalis of Meynert (nbM, substantia innominata) in the basal forebrain provides a single major source of cholinergic innervation for the entire cerebral cortex. We tested the effects of nbM lesions on rabbit P300-like potentials. The P300-like event-related potential (ERP) was recorded in 14 female adult white rabbits using a conventional auditory oddball paradigm. The probability of occurrence for the 2-kHz and 1-kHz stimulus tones was 90% (frequent) and 10% (rare), respectively. The nbM was destroyed bilaterally in seven rabbits referred to as the nbM (+) group. In the other seven rabbits [nbM (-) group], putamen nuclei (n=6) or amygdaloid nuclei (n=1) were destroyed bilaterally. The evoked responses were recorded before and 1 week after the destruction. In the nbM (+) group, P300 amplitude to rare stimuli significantly decreased after the lesion. In the nbM (-) group, no component of ERPs showed changes after the lesions. These results indicate that the nbM might be involved in the generation of the rabbit P300.

L-arginine administration during reperfusion improves pulmonary function

BACKGROUND

Nitric oxide is crucial to the maintenance of vascular homeostasis. Because nitric oxide levels decline upon lung reperfusion, infusion of L-arginine, a nitric oxide precursor, during reperfusion might prove effective at ameliorating reperfusion injury.

METHODS

Neonatal piglet heart-lung blocks were preserved with Euro-Collins solution for 12 hours, rewarmed at room temperature for 1 hour, and reperfused for 10 minutes with either whole blood (n = 5), whole blood containing L-arginine (10 mmol/L; n = 6), or leukocyte-depleted blood (n = 6) on an isolated, blood-perfused, working heart-lung circuit. After the initial 10 minutes, all blocks received whole blood for 4 hours. Control blocks were continuously perfused on the circuit without intervening ischemia (n = 6).

RESULTS

The partial pressure of oxygen in the whole blood group (113.8 +/- 33.1 mm Hg) was significantly less than in controls (417.3 +/- 6.2 mm Hg; p < 0.01). Lung compliance was significantly less in the whole blood group (0.8 +/- 0.2 mL/cm H2O) than in controls (2.9 +/- 0.4 mL/cm H2O; p < 0.01). The L-arginine and leukocyte-depleted blood groups showed no significant difference from controls.

CONCLUSIONS

L-Arginine infusion during reperfusion improves pulmonary function, making it a simple alternative to leukocyte depletion.

Single or bilateral lung transplantation for emphysema?

BACKGROUND

Most programs favor single lung transplantation for emphysema. However, this is controversial, and we have favored bilateral lung transplantation, confining single lung transplantation mainly to use in older patients and those of small stature.

METHODS

A retrospective analysis was done of 119 consecutive lung transplantation procedures for emphysema at Barnes Hospital between 1989 and 1994 (50 single lung, 69 bilateral lung transplants) to (1) identify outcome differences between the two groups and (2) define the appropriate role of these two procedures.

RESULTS

The single lung transplantation group was older and had a higher proportion of female patients. However, baseline pulmonary function (forced expiratory volume in 1 second), arterial oxygen tension, and exercise tolerance (6-minute walk distance) were similar. After transplantation, 90-day mortality (single lung transplantation 10% versus bilateral lung transplantation 7.2%; p = 0.74) and duration of mechanical ventilation, intensive care unit stay, and hospitalization were similar. Both groups achieved a significant and sustained improvement in forced expiratory volume, arterial carbon dioxide tension, arterial oxygen tension, and exercise tolerance within 3 months. However, the improvements in forced expiratory volume, arterial oxygen tension, and exercise tolerance were consistently significantly better in recipients of bilateral transplants at and beyond 6 months. Obliterative bronchiolitis was equally prevalent in both groups. Survival was similar but showed a trend toward better late survival in recipients of bilateral transplants (5-year actuarial survival: bilateral lung transplantation 53% versus single lung transplantation 41%).

CONCLUSIONS

We conclude that (1) both procedures are satisfactory options in emphysema, producing durable results; (2) bilateral lung transplantation is not associated with increased operative mortality or morbidity and achieves superior improvements in spirometry findings, oxygenation, exercise tolerance, and possibly late survival; and (3) the superior improvements in function (and late survival) after bilateral lung transplantation may be attributed to the presence of more pulmonary reserve after the onset of obliterative bronchiolitis.

Ligation of lateral carotid artery attenuates disturbance of brain function caused by subsequent cerebral ischemia in rabbits

The effects of right carotid artery ligation on the subsequent cerebral ischemia, induced by iron particle injection, in rabbits, were evaluated by recording somatosensory evoked potentials (SEPs) and cerebral blood flow (CBF) using laser Doppler flowmetry. Iron particle injection decreased CBF over 120 min and delayed SEP onset latency in rabbits with no previous carotid artery ligation (control group). In rabbits with a carotid ligation 3 days before, iron particle injection induced the decrease of CBF, as in the control group, but did not prolong the latency of SEP. Injection of iron particles induced only a transient decrease of CBF (less than 10 min) followed by an abrupt recovery, and no prolongation of SEP latency was observed in rabbits with a carotid ligation 6 days before. These results suggest that carotid artery ligation induces a beneficial effect on cerebral function during the subsequent ischemia, which is independent on the CBF changes.

Retroesophageal right subclavian artery originating from the aortic arch distal and dorsal to the left subclavian artery

In the cadaver of a Japanese 79 year-old man a retroesophageal right subclavian artery was observed to be derived from the arch of the aorta slightly distal and dorsal to the left subclavian artery. Its origin formed Kommerell's arterial diverticulum (50 mm in circumference), and it passed between the esophagus and the vertebral column and continued to the right to become the axillary artery. No right recurrent laryngeal nerve was observed. There was a right ansa subclavia around the subclavian artery. Although this anomaly is relatively rare, it is important as a cause of dysphagia lusoria.

The superficial ulnar artery originating from the axillary artery

An anomalous superficial ulnar artery was found during anatomical dissection in the right arm of an 83-year-old Japanese woman. It originated in the axillary artery, crossed over the median nerve, coursed ventral to the median nerve and the brachial artery, but superficial to the bicipital aponeurosis and the flexor muscles. At the palm it formed the superficial and deep palmar arches together with the branches of the radial artery. The brachial artery divided into the radial and common interosseous arteries in the cubital fossa.

Reliability of a questionnaire used to survey allergic disease in school

The reliability of a questionnaire which contained 21 items concerning asthma and allergies of the nose, skin, and eyes and other questions was evaluated by test-retest method. The questionnaire was the same as one used two years ago in a survey of allergic diseases found among elementary, junior and senior high school students in Shizuoka Prefecture, Japan. In order to evaluate its reliability, calculations were made of proportions of agreement, Cohen's kappa values and intraclass correlation coefficients. Both the proportions of agreement and the kappa values were fair, and all the intraclass correlation coefficients showed high values. The results suggest that there might be a slight effect of age, and that the articles which showed higher kappa values tended to be easy to answer, while the items in which kappa values were lower tended to consist of questions of multiple answers. This questionnaire can be regarded as useful for our original purpose of investigating allergic diseases. Among the kappa values of items, the values regarding diagnosis by doctor tended to be the largest. It was suggested that doctor's diagnosis was strongly convincing for patients. The reliability of this questionnaire survey can be regarded as satisfactory.

Cardiac gene transfer by intracoronary infusion of adenovirus vector-mediated reporter gene in the transplanted mouse heart

This study introduces a model for intracoronary gene transfer in murine cardiac isografts using adenovirus vectors. This approach may offer an opportunity to modulate alloreactivity after cardiac transplantation. Donor hearts were infected via the coronary arteries with a volume of 10(9) plaque-forming units per milliliter of a recombinant adenovirus containing the beta-galactosidase-encoding gene (Ad.CMVLacZ). In a control group, 200 microliters of normal saline solution was infused. The grafts were stored in 4 degrees C cold saline solution for 15 minutes, then transplanted heterotopically into syngeneic hosts (B10.BR). The grafts were harvested at 3, 7, 15, or 30 days (n = 5 for each group) after transplantation, and beta-galactosidase activity was assessed by histochemical staining (X-gal). All grafts were functioning when harvested. X-gal staining pattern was nonuniform with positive staining appearing in epicardial, myocardial, and endocardial cells, as well as in the vessel walls. The cells permissive to infection consisted predominantly of myocardial cells. The mean total numbers of beta-gal-positive staining cells per slice were 68.7 +/- 27.3 in the 3-day group, 330.4 +/- 53.8 in the 7-day group, 151.3 +/- 48.0 in the 15-day group, and 39.9 +/- 10.8 in the 30-day group, thus peaking in the 7-day group (p < 0.05). Control isografts (n = 5), retrieved at day 30, revealed no staining activity. In conclusion, our model demonstrates that intracoronary gene transfer to the transplanted murine cardiac grafts is feasible at the time of harvest. Adenovirus-mediated gene transfer produces widespread gene expression which, though perhaps transient, does not adversely affect myocardial structure or function. This technology may allow modification of graft immunogenicity in the future through the production of therapeutic proteins sufficient to modulate local immune responses.

Expression of mucinous ovarian-cancer antigen in hybrid-cells derived by fusing a malignantly transformed bloom-syndrome cell-line (bs-shi-4m ovc-mu) and mouse L-cell-line

The expression of mucinous ovarian cancer (OVC) antigen by hybrid cell lines derived by fusing a malignantly transformed Bloom syndrome (BS) cell line (BS-SHI-4M OVC-MU) and mouse L cells has been studied. Cell surfaces of 16 hybrids which grew 12-40 days post-fusion have been analysed by using a number of sera from mucinous OVC patients and indirect membrane immunofluorescence (IF). Three hybrids which appeared at a late stage (30-40 days in 24-well culture plates) were clearly positive in almost 100% of the hybrid cell population, while all of those which appeared earlier (in 12 days) were completely negative. Cytogenetic analysis showed that these three hybrids with positive mucinous OVC antigen contained human chromosome 22 or 22q-, though no metaphases from antigen negative population had 22 or 22q-. Therefore, we assign the gene for mucinous OVC antigen to the chromosome 22. Identification of chromosome 22 in hybrid cells was confirmed by the fluorescence in situ hybridization (FISH) analysis using chromosome 22 painting probe.

[Chromosome breakage syndrome and fragile X syndrome]

Chromosome instability is a characteristic cytogenetic feature of a number of genetically determined human disorders collectively known as chromosome breakage syndromes. Included among the disorders are Bloom's syndrome (BS), Fanconi's anemia (FA), ataxia telangiectasia (AT). In each of the syndromes chromosome instability exists in the form of increased frequencies of breaks and interchanges occurring either spontaneously or following treatment with various DNA-damaging agents. These diseases have in common an autosomal recessive transmission and an increased tendency to develop malignancies. The blood cells of subjects with AT, BS, or FA are significantly more radiosensitive than those of controls, particularly in the occurrence of chromosome aberrations.

Diagnostic relevance of abortion-associated human embryonic antigen expressed on the cell surface of tumour promoter-treated Bloom syndrome cells

We detected stable expression of human embryonic antigen associated with spontaneous abortion (HEAA) on the cell surface of a tumour promoter-treated B lymphoblastoid cell line (BS-SHY) originating from Bloom syndrome. We used indirect immunofluorescence and diluted serum from 44 patients who had recurrent spontaneous abortions. With the use of the panning procedure, we separated characteristic cells expressing strong HEAA. The BS-SHY-HEAA cells separated here would be useful for measuring serum antibody (against HEAA) produced by patients with recurrent abortions. It was also noted that aborters who received husbands' leukocyte immunization have lost this antibody, and have delivered successful pregnancies at term. Using HEAA proteins, we conducted Western blotting analysis for the amino acid sequencing (mol. wt 77 kDa). Amino acid sequencing data indicated that HEAA had 87.5% homology to the immunoglobulin (Ig) VHIII region in the framework. Recently, the protective value of high dose i.v. administration of immunoglobulin in the treatment of recurrent spontaneous abortions has been reported to be similar to that of leukocyte immunization. Therefore, the BS-SHY-HEAA cells appear to provide a valuable tool for rapid serological diagnosis and for evaluating the efficacy of immunotherapy with husbands' leukocytes in patients with recurrent spontaneous abortions.

Differential locations in the midbrain of distinct groups of vertical eye movement-related neurones in cat: their projections and direct connections with oculomotor neurones

The present study was undertaken to investigate the firing patterns, location and projections of vertical eye movement-related neurones in the Forel's field H (FFH), the interstitial nucleus of Cajal (INC), and reticular formation of the mesodiencephalic junction (MDJ) in chronically prepared alert cats. A total of 456 neurones in the medial MDJ with firing closely related to vertical eye movements was examined using antidromic microstimulation and spike-triggered averaging technique. On the basis of their firing patterns, these neurones were classified into five groups, i.e. burst neurones (BNs), burst-tonic neurones (BTNs), tonic neurones (TNs), augmenting neurones (ANs) and pause neurones (PNs). BNs were located mainly in the dorsomedial part of the FFH. Most of TNs were found more caudally than BNs. BTNs and PNs were located further caudally, within the INC and nearby reticular formation. ANs were located mainly in the dorsolateral part of the FFH. Both medium-lead BNs (MLBNs) and BTNs projected to the inferior rectus (IR) subdivision of the oculomotor nucleus on both sides. MLBNs projected to the trochlear nucleus as well through collateral branches of the axon projecting to the oculomotor nucleus. Downward and upward MLBNs made direct excitatory and inhibitory connections, respectively, with IR motorneurones. These results suggest that many kinds of neurones in the paramedian regions of MDJ play a significant role in the genesis of vertical eye movements.

Cancer antigen expression and chromosomal changes in a carcinogen-transformed bloom-syndrome B-lymphoblastoid cell-line

The phenomenon of sister chromatid exchange (SCE) is an interesting genetic event in metaphase chromosomes, even though its exact mechanism remains unknown. The fact that SCE can take place, whether 'spontaneously' or induced by various agents, is in itself important, for such an event, involving damage and possible repair of bilateral loci in chromosomes, presents opportunities for modification of the cell characters (e.g. oncogene activation). BS B- lymphoblastoid cell lines with high SCE levels were highly susceptible to malignant transformation by chemical carcinogenesis, in which cancer antigens are expressed on the cell surface with the disappearance of immunoglobulin (Ig), when the number of SCE exceeded 140 SCE per cell (over the baseline of 70 SCE per cell). The existence of an increased level of SCE which might cause unequal recombination between either sister chromatids or chromatids of homologous chromosomes may reflect phenomena secondary to malignant transformation or may have played a key role in initiation and maintenance of expression of the oncogenes and the antigens associated with cancers.

A human embryonic antigen associated with spontaneous-abortion is expressed on the cell-surface of a tumor promoter-treated bloom-syndrome B-lymphoblastoid cell-line

We detected stable expression of a human embryonic antigen associated with spontaneous abortion (HEAAb) on the cell surface of a tumor promoter (TPA)-treated B-lymphoblastoid cell line (BS-SHY) originating from Bloom syndrome (BS). We used indirect immunofluorescence (IF) and diluted serum from numerous patients who had recurrent spontaneous abortions (RSAs). With the use of the panning procedure, we separated characteristic cells expressing strong HEAAb. The BS-SHY-HEAAb cells separated would be useful for measuring serum antibody (against HEAAb) produced in the immune system of recurrent aborters. Using HEAAb proteins, we conducted Western blot (WB) analysis for the amino acid sequencing (MW, 77 KD). Amino acid sequencing data indicated that HEAAb had 87.5% homology to the immunoglobulin (Ig) VHIII region in the framework, and that differences were due to 2 amino acid alterations; from Gly (G) to Val (V) at the ninth residue and from Gly (G) to asp (D) at the sixteenth residue. No identical mutations were reported in the framework region of IgV(H)III. Even though the exact mechanism of TPA-induced HEAAb expression remains unknown, TPA increases BS SCE from 70 SCE per cell level to approximately 100, thus, it seems plausible that SCE plays some role in the expression of HEAAb, and plays a role in Ig disappearance from BS-SHY-HEAAb cells. Correlation of SCE, mutations causing Ig disappearance and HEAAb expression is discussed.

The recovery function of paired somatosensory evoked potentials in cerebral ischemic rabbits

In cerebral ischemia of different degrees, the amplitudes of somatosensory evoked potentials (SEPs) are facilitated or depressed. Different mechanisms might be responsible for the explanation of the contradictory phenomena. SEPs obtained using the paired stimulation method were employed in trying to find out the role of the functional changes of the inhibitory system in the brain during ischemia. Eight rabbits were used for recording the amplitude recovery curve of paired SEPs in the normal state, and the other ten were used for recording the recovery curve in different cerebral ischemic degrees. Cerebral ischemia was induced by the iron particle injection method. The attenuation of the depressed recovery function of the paired SEP amplitudes was detected during cerebral ischemia when SEP amplitudes were either facilitated or depressed. The results indicate that the function of the inhibitory system in the brain is selectively vulnerable during cerebral ischemia.

A new retinacular ligament and vein of the human temporomandibular joint

In the human temporomandibular joints of 14 Japanese cadavers, we observed a new retinacular ligament that connected to the retrodiskal pad posterolaterally and was accompanied by a vein draining the retrodiskal pad. This retinacular ligament originated from lateral to posterolateral part of the joint. The origin included the articular tubercle of the zygomatic process of the temporal bone. The ligament descended along the mandibular ramus to insert into the fascia of the masseter muscle at the mandibular angle. The vein originated from the venous plexus in the retrodiskal pad and ran parallel to the retinacular ligament, giving off branches to the retromandibular, transverse facial, and superfacial temporal veins. There were no remarkable differences in the size of the retinacular ligaments among individuals as well as between the left and right sides. The retinacular ligament had firm fibrous connections with the posterolateral part of the retrodiskal pad, where the external fibrous membrane of the articular capsule was lacking. These findings suggest that the retinacular ligament and its accompanying vein function together to maintain blood circulation during jaw movement and may also be related to the development of occlusal disorders.

Somatosensory evoked potentials in cerebral ischemia of rabbits

Twenty-one rabbits were used in the ischemic group and six in the control group. Cerebral ischemia of variable degree was induced by Fe particle injection method. Somatosensory evoked potentials (SEPs) and cerebral blood flow (CBF) were compared when the CBF levels decreased to their minimum. The latency of the SEPs increased along with the decrease of the CBF when it was lower than 20 ml/100 g/min (68% of the pre-ischemic control level). This may be related to the ischemic change of the white matter. The amplitude showed diphasic changes. When the CBF decreased below 20 ml/100 g/min, the amplitude increased; when the CBF was lower than 11 ml/100 g/min (38% of the pre-ischemic level), it decreased. These results indicate that the functions of the cerebral cortex might be excited in mild ischemia, and be suppressed in severe ischemia.

[The pulmonary air meniscus sign in a case of sclerosing hemangioma]

A 57-year-old woman was admitted to our hospital because of a slowly growing pulmonary tumor with a 34 year history. Chest roentgenogram on admission showed a 42 mm sharply demarcated solitary tumor in the left upper lobe. Chest CT revealed a slit-like pulmonary air meniscus. Left upper lobectomy was performed. A specimen from the resected lung histologically showed solid, papillary and hemorrhagic patterns, and the diagnosis of pulmonary sclerosing hemangioma was therefore made. Pulmonary air meniscus sign in pulmonary sclerosing hemangioma is rare. We think one possible mechanism in the production of an air meniscus sign in sclerosing hemangioma is bleeding in communication with a bronchus.

Chordal reconstruction with polytetrafluoroethylene (PTFE) sutures for mitral regurgitation

Chordal reconstruction of the mitral valve using CV4 or CV5 polytetrafluoroethylene (PTFE) (Gore-Tex. Flagstaff, AZ, USA) sutures was performed in seven patients with mitral regurgitation (MR) to ascertain its efficacy. The MR had been caused by prolapse of the anterior leaflet in three patients, the posterior leaflet in two, and both leaflets in two; five of the patients had an MR of grade III or IV. There was one hospital death, which occurred in a patient whose MR had resulted from papillary muscle dysfunction caused by a myocardial infarction (MI). Chordal reconstruction failed and was converted to a mitral valve replacement in two patients, one of whom had suffered a MI and another who had a congenital papillary muscle anomaly. The remaining five patients all underwent successful chordal reconstruction with PTFE sutures, resulting in the disappearance of the MR in two patients and an improvement to grade I in three patients. Although the longest follow-up period has been only 1 year, the MR has not worsened. This technique is relatively easy to perform, and allows almost all the mitral apparatus to remain in situ, while enabling repair of the mitral valve, regardless of the state of the diseased chordae.

[Identification of the most appropriate time for lung transplantation in the patients with idiopathic interstitial pneumonitis]

In order to identify the most appropriate time for lung transplantation, we examined the natural courses of eight patients who died of idiopathic interstitial pneumonitis (IIP). Five of eight patients died within two years after they were diagnosed as IIP and six died within one year after the last admission. As the disease progressed, arterial oxygen pressure tended to decrease and serum LDH level to increase. But no parameter was able to predict the natural courses of patients. We conclude that it is very difficult to identify the most appropriate time for lung transplantation and the prognosis of IIP patient is very poor. Therefore as soon as patients are diagnosed as IIP, it is mandatory to assess their eligibility for lung transplantation.

Detection and characterization of antibodies to bacterial heat-shock protein 60 in sera of patients with primary biliary cirrhosis

The enzyme-linked immunosorbent assay (ELISA) with bacterial heat-shock protein 60 (HSP60) purified from Yersinia enterocolitica (Ye) revealed that the antibodies directed against YeHSP60 existed in sera of patients with primary biliary cirrhosis (PBC). To characterize the epitope specificity of the antibodies in patients, the epitope mapping of HSP60 by means of the antibodies was performed. The results have suggested that the epitope recognized with anti-HSP60 antibodies in PBC relates to the amino acid sequence of YeHSP60 molecule as follows: DLGQAKRVVINKDTTIIIDGVGDEAAIQGRLAQIRQQIEEATSDYDKEK.

Panning and immune electron-microscopic study of mucinous ovarian-cancer antigen-specific cells derived from malignantly transformed bloom-syndrome B-lymphoblastoid cells

We separated characteristic mucinous ovarian cancer (OVC) antigen cells from malignantly transformed Bloom syndrome (BS) cell line (BS-SHI-4M) with the panning procedure using OVC patients sera. We undertook an immune electron-microscopic and scanning electron-microscopic study to acquire information regarding the antigenic determinant of the membrane using pre-embedding method, as well as immunofluorescence (IF) study. The distribution of Protein A colloidal gold (PAG) grains on the cell membrane of mucinous OVC antigen cells paralleled that of fluorescein-conjugated anti-human IgG observed in the IF study. The three patterns of PAG labeling of uniform labeling, uniform partial labeling, and partial labeling of one side of the cell paralleled the three patterns of IF labeling observed under IF. These findings strongly suggest the immunological reaction of BS-SHI-4M OVC-MU antigen cells with the antibody of mucinous OVC patient serum. Western blot analysis demonstrated that the antigen which characterizes mucinous OVC has a band at 84000 MW.

Resistance to 1-Beta-d-arabinofuranosylcytosine and hypersensitivity to bleomycin in ataxia-telangiectasia B-lymphoblastoid cell-lines

Three ataxia telangiectasia (AT) B-lymphoblastoid cell lines (B-LCLs) were examined for the chromosome aberrations induced by a DNA replication and repair inhibitor, 1-beta-D-arabinofuranosylcytosine (ara-C), and the effects of ara-C on the frequencies of chromosome aberrations caused by bleomycin (BLM). All these AT cell lines exhibited resistance to ara-C compared with normal and Bloom syndrome (BS) cells. In contrast with normal and BS cells, ara-C did not enhance chromosome aberrations produced by BLM in AT cells, although these cells showed hypersensitivity to BLM. After treatment with 1 X 10(-5) M ara-C for 24 h, total frequencies of chromosome aberrations in AT cells were 0.095-0.115/cell, which is about 6 times lower than those in normal (0.625/cell) and BS cells (0.775/cell). Following combination treatment with tetrahydrouridine (THU) and ara-C, we found that the frequencies of chromosome aberrations in AT B-LCLs were greatly increased compared with treatment with ara-C alone. Furthermore, when AT cells were pretreated with THU in combination with ara-C, then treated with BLM, a great synergistic enhancement of chromosome aberrations was observed. Because THU is an exclusive inhibitor of cytidine deaminase, these results strongly indicate that in AT B-LCLs there could be overproduction of cytidine Jeaminase, which is responsible for ara-C resistance. On the other hand, combination of THU and deoxycytidine (dCyd) significantly reduced chromosome aberrations induced by BLM in AT cells, although dCyd alone had no effect on bleomycin-induced chromosome aberrations. Break point distributions on chromosome bands following treatment with BLM or ara-C plus THU, alone or in combination, were examined and are discussed.

Medium-lead burst neurons related to vertical saccades in cat Forel's field H: input from vestibular nucleus

The present study was undertaken to investigate synaptic connections between medium-lead burst neurons (MLBNs) related to vertical saccades in Forel's field H and vestibular nucleus (VN) neurons. Extracellular spikes were recorded from single MLBNs and their responses to VN stimulation were examined using chronically prepared alert cats. Twenty of 30 upward MLBNs and 10 of 22 downward MLBNs could be synaptically activated mainly by the ipsilateral VN stimulation with spike latencies of 2.2-12.0 and 1.9-11.7 ms, respectively. These results suggest that there exist di- or polysynaptic connections which transfer velocity signals for vertical saccades from the ipsilateral vestibular nucleus neurons to the vertical MLBNs.

Projections of vertical eye movement-related and head rotation-related neurons in the medial mesodiencephalic junction to pontine reticular formation in cat

Spikes of single neurons related to vertical eye movements and vertical head rotation were recorded extracellularly in the medial mesodiencephalic junction (MDJ) of chronically prepared alert cats, and their antidromic responses to stimulation of the pontine reticular formation (PRF) were studied. Among the vertical eye movement-related-neurons, augmenting neurons (ANs) and tonic neurons (TNs) were activated antidromically from the lateral PRF. Stimulation of the midline PRF activated antidromically mainly ANs, long-lead burst neurons (LLBNs) and upward medium-lead burst neurons (MLBNs). The head rotation-related neurons were antidromically activated from the lateral PRF but not-from the midline PRF. These results suggest that some MDJ neurons related to vertical eye movements or head rotation directly project to the paramedian PRF.

Oxygen uptake and carbon dioxide elimination during controlled hypotension induced by prostaglandin E1 or nitroglycerin

To compare the effects of prostaglandin E1 (PGE1) with those of nitroglycerin (NTG) on whole body metabolism (oxygen uptake (VO2) and carbon dioxide elimination (VCO2) during induced hypotension, we have studied 16 patients undergoing elective surgery (radical mastectomy or tympanoplasty). The patients were allocated randomly in a non-blinded manner to two groups. Baseline characteristics were similar in the two groups. Arterial pressure was controlled at about 70% of the baseline value using PGE1 or NTG. VO2, VCO2, gas exchange ratio (RQ) and deadspace ventilation ratio (VD/VT) were measured continuously with mass spectrometry. The values for all variables were measured for 10 min at five times (1 = start of surgery (baseline value); 2 = start of drug infusion; 3 = 60 min after start of drug infusion; 4 = drug infusion stopped; 5 = surgery finished). VO2, VCO2, RQ and VD/VT values were relatively constant in both groups during surgery. The balance between oxygen supply and oxygen demand was maintained during induced hypotension with PGE1 or NTG.

Interaction of bloom-syndrome cellular cancer antigens with sera of malignant-lymphoma patients - an immunological and cytogenetical study

We have analyzed chromosome abnormalities in 32 B-cell lymphoma (B-ML), 29 T-cell lymphoma (T-ML) and 29 adult T-cell leukemia/lymphoma (ATL) patients and tested the reactivity of Bloom syndrome (BS) derived malignant lymphoma (ML) antigen with the sera in these patients with immunofluorescence (IF) and Western blotting (WB) protocols. Among the cases analyzed, 14q32 abnormalities were observed in 11 (B-ML), 8 (T-ML) and 10 (ATL) cases; these changes were accompanied by complex numerical and structural abnormalities. In the IF and WB analyses, the reactivity of BS ML antigen and ML sera showed high positivity in over 85% of ML cases and appeared to clearly raise the number of successful diagnoses as compared to the chromosome finding, giving 50-60% success in identifying ML. WB analyses demonstrated common ML antigen band at 97 KD (B-ML, T-ML and ATL). DNA analysis from BS ML antigen cells (BS-SHI-4M ML) showed rearranged fragments in both T-cell receptor (TCR alpha3 and immunoglobulin joining region (I(g)J(H) genes. The present findings of rearrangements of TCR alpha3 and I(g)J(H) in BS-SHI-4M ML antigen cells possibly support the common reactivity of BS ML antigen to B- and T-ML and ATL sera. The possible role of immunoglobulin heavy chain variable region (I(g)V(H) gene mutation and ML antigen expression is discussed.

[Is it safe and available to transfuse directly the shed mediastinal blood after cardiac surgery?]

Autotransfusion of the shed mediastinal blood after cardiac operations was performed in 20 cases (ATS group). Safety and efficacy of the autotransfusion were studied comparing with the 10 cases without autotransfusion (control group). A 65.1 +/- 17.1% of bleeding volume within 24 hours after surgery was autotransfused in the ATS group. The ATS group received 1,396 +/- 1,674 ml of the banked blood compared with 780 +/- 1,194 ml for the control group. There was no significant difference between two groups in regard to saving the banked blood. Hematological and biochemical studies after surgery in the ATS and control groups revealed that CPK, BUN and creatinine of the ATS group were significantly higher than those of the control group, although these changes were transitory and trivial. However, prothrombin time of the ATS group was lower than that of control group, so there may be the possibility that this technique itself increases the hemorrhage. Since the cardiotomy filter was obstructed with clots in cases of massive bleeding, shed mediastinal blood may not be fully defibrinogenated in the cases with massive bleeding. These results lead to the following conclusions: autotransfusion of the shed mediastinal blood after cardiac operations is a safe method, but the efficacy of it is doubtful.

Characteristics of a 28-kDa collagenous protein extracted with guanidine from EDTA-demineralized rabbit alveolar bone

Bone proteins in alveolar bone of mandibles from young adult rabbits (3-month-old) were extracted with 4.0 M guanidine hydrochloride (GuHCl), followed by 0.5 M ethylenediaminetetraacetate, and again with 4.0 M GuHCl (G2-ext). The proteins in the G2-ext were fractionated on a gel-filtration column, followed by an anion-exchange column in the presence of 7.0 M urea. A 28-kDa protein was isolated from the G2-ext. The purified 28-kDa protein showed intense staining with silver on SDS-PAGE slab-gel under reducing conditions. This protein was digested with bacterial collagenase, and a 19-kDa fragment appeared on the gel. However, the protein was not susceptible to reduction with cyanogen bromide. The protein did not bind to hydroxyapatite crystals in the presence of 7.0 M urea, and also did not bind to some lectins. On SDS-PAGE under non-reducing conditions, the protein migrated as two bands; a new band appeared at approximately the 85-kDa region in addition to the original 28-kDa band. The amino acid compositions of the protein were similar to those of the alpha 1-pN-propeptide of type I procollagen obtained from other tissues.

Decrease in aortic distensibility after an extended aortic reconstruction for Marfan's syndrome as a cause of postoperative acute aortic dissection DeBakey type I: a report of two cases

Two cases of Marfan's syndrome underwent a reconstruction of the abdominal aorta and descending thoracic aorta. A replacement of the abdominal aorta with visceral arteries as well as a wrapping of the descending thoracic aorta was performed in case 1 while a reconstruction of the descending thoracic aorta and infra-renal abdominal aorta was done in case 2. After the reconstruction, both cases developed acute aortic dissection DeBakey type I. Another reconstruction of the ascending aorta was then urgently performed. Cardiac catheterization after the second operation in case 1 revealed that the distensibility of the aorta had disappeared at the location of the vascular prosthesis while it had also decreased at the wrapped portion, and the maximum dp/dt of the ascending aorta also increased. Increases in the pulse pressure and pulse rate after the first operation were observed in both cases. These hemodynamic changes, which were produced by a decreased distensibility of the reconstructed aorta, increased the mechanical stress to the native aortic wall, and may have been one of the causes of acute aortic dissection DeBakey type I occurring after reconstruction with a prosthesis.

[Chordal reconstruction with polytetrafluoroethylene (PTFE) suture for mitral regurgitation caused by prolapsed anterior leaflet]

Cardiac surgeons have hesitated to perform valvuloplasty for MR caused by elongated or ruptured chordae of the anterior leaflet (AL) of the mitral valve. We experienced three cases of successful chordal reconstruction (CR) to the AL last year. Two of them were due to elongation of all chordae tendineae to the AL. Four CRs, one chordal shortening, cleft closure and ring annuloplasty (AP) were performed in one case, and 8 CRs to the AL, two to the posterior leaflet, commissural closure and ring AP in another. In the third case 2 CRs combined with Reed's AP, closure of ASD and tricuspid AP were performed. The MR disappeared in one case and improved to grade I in others postoperatively. NYHA classes improved from class III or IV to I or II postoperatively. The MRs have not increased 6 to 12 months after the surgery. The CR with PTFE suture enabled to do the valvuloplasty for the chordal abnormalities of the AL without valve resection. This technique seems to be adequate for repairing a major prolapse of the AL caused by multiple chordal abnormalities.

A pulsatile cardiopulmonary bypass system that prevents negative pressure at the membrane oxygenator

Negative pressure is a problem in pulsatile cardiopulmonary bypass (CPB). To avoid this, the authors designed a pulsatile CPB system containing a Sarns centrifugal pump (CP) and a Univox membrane oxygenator, in which the inertial flow is not obstructed by the CP. In both an in vitro study and a clinical study, negative pressure was not observed in the arterial line of the CPB circuit when this system was used. When a roller pump (RP) was used, however, instead of a CP, negative pressure did occur. In a clinical study using this system, mean pulse pressure was 36 mmHg and hemolysis, expressed as the rate of rise in plasma free hemoglobin from 10 to 70 min of CPB, was 26.2 mg/dl/hr, which did not exceed that seen with a pulsatile CPB using an RP instead of a CP. The hemolysis seen in the study caused no clinical problems. Thus, pulsatile CPB using a CP and Univox membrane oxygenator should be considered for clinical use to prevent the occurrence of negative pressure.

[Reexpansion pulmonary edema after removal of a huge localized mesothelioma]

A 70-year-old female with hypoglycemia was admitted to our hospital for progressive dyspnea. In chest X-ray film, a mass occupied two thirds of the left hemi-thorax followed by the right shift of the mediastinum. Thoracotomy revealed that a huge tumor grew from the left upper lobe and the diaphragm without invasion. The resected tumor was 2550 g in weight. Histological diagnosis was benign fibrous mesothelioma. A large amount of expectoration started soon after the resection of the tumor. Measurement of protein in tracheal fluid and serum revealed that the event resulted from the reexpansion of the left lung after the huge mass removal. The patient recovered from pulmonary edema followed by steroid administration and respiratory management. We consider that it is useful to measure the protein in tracheal fluid and serum for diagnosis of reexpansion pulmonary edema.