Association between glomerular filtration rate and plasma N-terminal pro-atrial natriuretic peptide concentration in dogs

OBJECTIVES

To investigate the association between plasma N-terminal pro-atrial natriuretic peptide concentration and glomerular filtration rate in dogs.

MATERIALS AND METHODS

Dogs were classified into four categories by bodyweight. Dogs were divided into four groups (Groups 1 to 4) based on glomerular filtration rate estimates using plasma iohexol clearance per bodyweight category. Generalised linear models were built to explore the relationship between plasma N-terminal pro-atrial natriuretic peptide concentration and glomerular filtration rate and the effect of confounders on plasma N-terminal pro-atrial natriuretic peptide concentration.

RESULTS

Fifty-three dogs were included (Group 1, 25; Group 2, seven; Group 3, five; and Group 4, 16). The medians (interquartile range) N-terminal pro-atrial natriuretic peptide concentrations for Groups 1 to 4 were 7224 pg/mL (4766 to 10,254 mg/dL), 8958 pg/mL (4935 to 11,271 mg/dL), 9280 pg/mL (9195 to 10,384 mg/dL) and 12,683 pg/mL (9133 to 19,217 mg/dL), respectively. Group 4, estimated to have the highest reduction in glomerular filtration rate, had a higher plasma N-terminal pro-atrial natriuretic peptide concentration than Groups 1 to 3. Based on the final generalised linear model, influencing factors for plasma N-terminal pro-atrial natriuretic peptide concentration were plasma iohexol clearance (-0.136; 95% confidence interval, -0.227 to -0.046) and bodyweight (-0.058; 95% confidence interval, -0.098 to -0.018).

CLINICAL SIGNIFICANCE

N-terminal pro-atrial natriuretic peptide concentration is associated with the glomerular filtration rate.

Higher Blood Uric Acid in Female Humans and Mice as a Protective Factor against Pathophysiological Decline of Lung Function

The oxidant/antioxidant imbalance plays a pivotal role in the lung. Uric acid (UA), an endogenous antioxidant, is highly present in lung tissue, however, its impact on lung function under pathophysiological conditions remains unknown. In this work, pharmacological and genetic inhibition of UA metabolism in experimental mouse models of acute and chronic obstructive pulmonary disease (COPD) revealed that increased plasma UA levels improved emphysematous phenotype and lung dysfunction in accordance with reduced oxidative stress specifically in female but not in male mice, despite no impact of plasma UA induction on the pulmonary phenotypes in nondiseased mice. In vitro experiments determined that UA significantly suppressed hydrogen peroxide (H₂O₂)-induced oxidative stress in female donor-derived primary human bronchial epithelial (NHBE) cells in the absence of estrogen, implying that the benefit of UA is limited to the female airway in postmenopausal conditions. Consistently, our clinical observational analyses confirmed that higher blood UA levels, as well as the SLC2A9/GLUT9 rs11722228 T/T genotype, were associated with higher lung function in elderly human females. Together, our findings provide the first unique evidence that higher blood UA is a protective factor against the pathological decline of lung function in female mice, and possibly against aging-associated physiological decline in human females.

Melinjo seed extract increases adiponectin multimerization in physiological and pathological conditions

Melinjo seed extract (MSE) contains large amounts of polyphenols, including dimers of trans-resveratrol (e.g. gnetin C, L, gnemonoside A, B and D), and has been shown to potentially improve obesity. However, there is no clinical evidence regarding the anti-obesity effects of MSE, and its mechanisms are also unclear. We investigated the hypothesis that MSE supplementation increases the adiponectin (APN) multimerization via the up-regulation of disulfide bond A oxidoreductase-like protein (DsbA-L) under either or both physiological and obese conditions. To investigate the effect of MSE on the physiological condition, 42 healthy young volunteers were enrolled in a randomized, double-blind placebo-controlled clinical trial for 14 days. The participants were randomly assigned to the MSE 150 mg/day, MSE 300 mg/day or placebo groups. Furthermore, in order to investigate the effect of MSE on APN levels under obese conditions, we administered MSE powder (500 or 1000 mg/kg/day) to control-diet- or high-fat-diet (HFD)-fed C57BL/6 mice for 4 weeks. All participants completed the clinical trial. The administration of MSE 300 mg/day was associated with an increase in the ratio of HMW/total APN in relation to the genes regulating APN multimerization, including DsbA-L. Furthermore, this effect of MSE was more pronounced in carriers of the DsbA-L rs191776 G/T or T/T genotype than in others. In addition, the administration of MSE to HFD mice suppressed their metabolic abnormalities (i.e. weight gain, increased blood glucose level and fat mass accumulation) and increased the levels of total and HMW APN in serum and the mRNA levels of ADIPOQ and DsbA-L in adipose tissue. The present study suggests that MSE may exert beneficial effects via APN multimerization in relation to the induction of DsbA-L under both physiological and obese conditions.

Azithromycin Inhibits Constitutive Airway Epithelial Sodium Channel Activation in Vitro and Modulates Downstream Pathogenesis in Vivo

Epithelial sodium channel (ENaC) is an amiloride-sensitive sodium ion channel that is expressed in epithelial tissues. ENaC overexpression and/or hyperactivation in airway epithelial cells cause sodium over-absorption and dysregulated ciliary movement for mucus clearance; however, the agents that suppress constitutive airway ENaC activation are yet to be clinically available. Here, we focused on macrolides, which are widely used antibiotics that have many potential immunomodulatory effects. We examined whether macrolides could modulate constitutive ENaC activity and downstream events that typify cystic fibrosis (CF) and chronic obstructive pulmonary diseases (COPD) in in vitro and in vivo models of ENaC overexpression. Treatment of ENaC-overexpressing human bronchial epithelial cells (β/γENaC-16HBE14o- cells) with three macrolides (erythromycin, clarithromycin, azithromycin) confirmed dose-dependent suppression of ENaC function. For in vivo studies, mice harboring airway specific βENaC overexpression (C57BL/6J-βENaC-transgenic mice) were treated orally with azithromycin, a well-established antimicrobial agent that has been widely prescribed. Azithromycin treatment modulated pulmonary mechanics, emphysematous phenotype and pulmonary dysfunction. Notably, a lower dose (3 mg kg^-1) of azithromycin significantly increased forced expiratory volume in 0.1 s (FEV0.1), an inverse indicator of bronchoconstriction. Although not statistically significant, improvement of pulmonary obstructive parameters such as emphysema and lung dysfunction (FEV0.1%) was observed. Our results demonstrate that macrolides directly attenuate constitutive ENaC function in vitro and may be promising for the treatment of obstructive lung diseases with defective mucociliary clearance, possibly by targeting ENaC hyperactivation.

Intratracheal GLP-1 receptor agonist treatment up-regulates mucin via p38 and exacerbates emphysematous phenotype in mucus hypersecretory obstructive lung diseases

Glucagon-like peptide-1 (GLP-1) is a gastrointestinal hormone that stimulates glucose-mediated insulin production by pancreatic beta cells. It is also associated with protective effects in multiple tissues. GLP-1 receptor is highly expressed in pulmonary tissue, hinting possible pulmonary delivery of GLP-1 drugs. However, little is known about the role of GLP-1 signaling in the lung, especially in mucus hypersecretory obstructive lung diseases. Here, we showed that treatment with exendin-4, a clinically available GLP-1 receptor agonist, up-regulates mucin expression in normal airway epithelial cells and in the lung of normal mice, indicating mucus stimulatory effect of GLP-1 under physiological condition. Exendin-4 also increased mucin expression in in vitro cellular and in vivo murine models of obstructive lung diseases via the activation of p38 MAP kinase. Notably, mucin induction in vivo exacerbated key pulmonary abnormalities including emphysematous phenotypes, implying that GLP-1 signaling in the lung is detrimental under pulmonary obstructive condition. Another GLP-1 receptor agonist liraglutide had similar induction of mucin. Together, our studies not only demonstrate novel physiological and pathological roles of GLP-1 in the lung but may also caution against the clinical use of inhaled GLP-1 receptor agonists in the patients with obstructive lung diseases.

Auto-measure emphysematous parameters and pathophysiological gene expression profiles in experimental mouse models of acute and chronic obstructive pulmonary diseases

Pulmonary emphysema, inflammation and senescence-like phenotype are pathophysiological characteristics of chronic obstructive pulmonary disease (COPD). Recently, a murine model of COPD has been established by inducing airway-specific overexpression of epithelial Na⁺ channel β subunit (βENaC-Tg mice). However, little is known about the histological and biochemical differences between βENaC-Tg mice and an existing acute emphysematous mouse model (elastase-induced model). Here, we first utilized whole lung image-based quantification method for histological analysis to determine auto-measure parameters, including alveolar area, alveolar perimeter, (major axis + minor axis)/2 and Feret diameter. Even though the extent of emphysema was similar in both models, the coefficient of variation (CV) of all histological parameters was smaller in βENaC-Tg mice, indicating that βENaC-Tg mice show homogeneous emphysema as compared with elastase-induced acute model. Expression analysis of lung tissue RNAs further revealed that elastase-induced model exhibits transient changes of inflammation markers (Kc, Il-6, Lcn2) and senescence-related markers (Sirt1, p21) at emphysema-initiation stage (1 day), which does not last until emphysema-manifestation stage (3 weeks); while the up-regulation is stable at emphysema-manifestation stage in βENaC-Tg mice (14-week old). Thus, these studies demonstrate that βENaC-Tg mice exhibit diffuse-type emphysema with stable expression of inflammatory and senescence-like markers.

Integrative expression analysis identifies a novel interplay between CFTR and linc-SUMF1-2 that involves CF-associated gene dysregulation

Cystic fibrosis transmembrane regulator (CFTR) is a cyclic AMP-dependent Cl^- channel, and its dysfunction, due to CFTR gene mutations, causes the lethal inherited disorder cystic fibrosis (CF). To date, widespread dysregulation of certain coding genes in CF airway epithelial cells is well studied and considered as the driver of pulmonary abnormality. However, the involvement of non-coding genes, novel classes of functional RNAs with little or no protein-coding capacity, in the regulation of CF-associated gene dysregulation is poorly understood. Here, we utilized integrative analyses of human transcriptome array (HTA) and characterized 99 coding and 91 non-coding RNAs that are dysregulated in CFTR-defective CF bronchial epithelial cell line CFBE41o-. Among these genes, the expression level of linc-SUMF1-2, an intergenic non-coding RNA (lincRNA) whose function is unknown, was inversely correlated with that of WT-CFTR and consistently higher in primary human CF airway epithelial cells (DHBE-CF). Further integrative analyses under linc-SUMF1-knockdown condition determined MXRA5, SEMA5A, CXCL10, AK022877, CTGF, MYC, AREG and LAMB3 as both CFTR- and linc-SUMF1-2-dependent dysregulated gene sets in CF airway epithelial cells. Overall, our analyses reveal linc-SUMF1-2 as a dysregulated non-coding gene in CF as well as CFTR-linc-SUMF1-2 axis as a novel regulatory pathway involved in CF-associated gene dysregulation.

Zinc Deficiency via a Splice Switch in Zinc Importer ZIP2/SLC39A2 Causes Cystic Fibrosis-Associated MUC5AC Hypersecretion in Airway Epithelial Cells

Airway mucus hyperproduction and fluid imbalance are important hallmarks of cystic fibrosis (CF), the most common life-shortening genetic disorder in Caucasians. Dysregulated expression and/or function of airway ion transporters, including cystic fibrosis transmembrane conductance regulator (CFTR) and epithelial sodium channel (ENaC), have been implicated as causes of CF-associated mucus hypersecretory phenotype. However, the contributory roles of other substances and transporters in the regulation of CF airway pathogenesis remain unelucidated. Here, we identified a novel connection between CFTR/ENaC expression and the intracellular Zn^2 + concentration in the regulation of MUC5AC, a major secreted mucin that is highly expressed in CF airway. CFTR-defective and ENaC-hyperactive airway epithelial cells specifically and highly expressed a unique, alternative splice isoform of the zinc importer ZIP2/SLC39A2 (ΔC-ZIP2), which lacks the C-terminal domain. Importantly, ΔC-ZIP2 levels correlated inversely with wild-type ZIP2 and intracellular Zn^2 + levels. Moreover, the splice switch to ΔC-ZIP2 as well as decreased expression of other ZIPs caused zinc deficiency, which is sufficient for induction of MUC5AC; while ΔC-ZIP2 expression per se induced ENaC expression and function. Thus, our findings demonstrate that the novel splicing switch contributes to CF lung pathology via the novel interplay of CFTR, ENaC, and ZIP2 transporters.

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Zinc deficiency is a common feature in both CFTR-defective (CF) and ENaC-hyperactive (CF-like) airway epithelial cells.

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A splice switch from WT-ZIP2 to ΔC-ZIP2 as well as other ZIPs down-regulation caused zinc deficiency in CF and CF-like cells.

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Lower intracellular Zn^2 + levels contributed to CF-associated MUC5AC hypersecretion in airway epithelial cells.

The role of zinc in the pathogenesis of CF lung disease is not well understood. We utilized human CF patient-derived cell lines and primary cells as well as murine CF model, and identified zinc deficiency as a common characteristic in CF models. Down-regulation of several zinc importers (ZIPs) in CF cells caused zinc deficiency, which is sufficient for induction of MUC5AC, a major secreted mucin that exacerbates CF pathogenesis. Especially, strong contribution of ΔC-ZIP2, a novel ZIP2 splice isoform, in the regulation of CF-associated MUC5AC hypersecretion was clearly demonstrated. The study refined the importance of zinc in airway homeostasis.

[Radiofrequency modified maze operation for chronic atrial fibrillation with ASD; report of a case]

A 61-year-old man with congestive heart failure was referred to our hospital and diagnosed as atrial septal defect (ASD) [Qp/Qs = 1.6] with chronic atrial fibrillation. Occurrence of atrial fibrillation was supposed to be the cause of heart failure rather than L-R shunt of ASD. The patient was successfully operated on with the use of routine cardiopulmonary bypass. Radiofrequency modified maze procedure was done, and then small ASD (1 cm of diameter) was closed with patch. Postoperative transthoracic Doppler echocardiography confirmed clear A wave for transmitral and transtricuspid flow. The patient recovered uneventfully and was discharged in stable sinus rhythm and has been drug free since then.

Mechanism of apoptosis induced by a lysosomotropic agent, L-Leucyl-L-Leucine methyl ester

Lysosomes are fundamental for cell growth, and thus inhibition of the lysosomal function often leads to cell death. L-Leucyl-L-leucine methyl ester (LeuLeuOMe) is a lysosomotropic agent that induces apoptosis of certain immune cells. LeuLeuOMe is taken up through receptor-mediated endocytosis, and then converted into (LeuLeu)n-OMe (n>3) by dipeptidyl peptidase I (DPPI) in lysosomes, which reportedly causes rupture of the lysosomes and DNA fragmentation. In this study we examined how lysosomal damage causes DNA fragmentation in LeuLeuOMe-treated HL-60 cells. When acridine orange was employed to monitor lysosomal membrane integrity, orange or red granular fluorescence was seen in normal cells. In contrast, LeuLeuOMe-treated cells showed orange, yellow or green cellular fluorescence all over the cytoplasm, suggesting that LeuLeuOMe induced a loss of lysosomal membrane integrity. The loss was inhibited by a DPPI inhibitor, GlyPheCHN2 (GFCHN2), but not by a caspase-3 inhibitor, Ac-DEVD-CHO, indicating that a condensation product was responsible for the loss. LeuLeuOMe also induced the activation of caspase-3-like protease and DNA fragmentation, both of which were inhibited by either GFCHN2 or Ac-DEVD-CHO. Therefore, the activation of caspase-3-like protease links the loss of lysosomal membrane integrity to DNA fragmentation during apoptosis induced by LeuLeuOMe.

Long-term follow-up of large flat colorectal tumors resected endoscopically

BACKGROUND AND STUDY AIM

When a large flat colorectal tumor is excised by piecemeal endoscopic resection, it is not possible to obtain suitable specimens for histopathological examination to assess whether the resection has been complete. We prospectively analysed follow-up colonoscopy examinations of endoscopic polypectomy resection sites for residual lesions.

PATIENTS AND METHODS

A total of 24 patients with large flat colorectal tumors were treated using an endoscopic submucosal saline injection technique. The resection site was prospectively examined for residual lesions using a magnifying colonoscope, at 3, 6, 12 and 24 months postoperatively.

RESULTS

None of the 5 patients who underwent en bloc resection exhibited residual lesions postoperatively. Of the 19 patients who underwent piecemeal resection, one died of an asthma attack and 18 were followed up. Residual lesions were detected in four of these 18 patients (three adenomas and one cancer), which were resected endoscopically. When the tumor was resected endoscopically en bloc and was judged histologically to be completely resected, residual lesions were not detected at follow-up. However, residual lesions were detected in 22.2 % of patients 3 months after initial resection when polyps were resected piecemeal. After treatment, residual lesions were detected in two patients (11.1 %) at 24 months.

CONCLUSION

After piecemeal endoscopic resection for large flat colorectal tumors, it is necessary to follow-up and remove residual lesions endoscopically every 3 months until they all are removed.

Increased rectal wall thickness may predict relapse in ulcerative colitis: a pilot follow-up study by ultrasonographic colonoscopy

BACKGROUND AND STUDY AIMS

Ulcerative colitis is a chronic inflammatory bowel disease with repeated remission and relapse, although the occurrence of relapse is difficult to predict. We performed a prospective study to determine whether there is a relationship in ulcerative colitis between the inflammatory changes identified by endoscopic ultrasonography (EUS) and relapse.

PATIENTS AND METHODS

Participants were 23 ulcerative colitis patients who had not suffered a relapse for 1 month, with a Seo activity index less-than-or-equal 150 and Baron grade 1 at colonoscopy. The thickness of the first to the third layer of the rectal wall in these patients was measured by EUS at the start of the study. They were subsequently followed up for 1 year to record any relapses, defined as having a Seo activity index > 150 and Baron grade greater-than-or-equal 2 at colonoscopy.

RESULTS

Relapse occurred in eight patients. The mean activity index of the relapsed patients was 187.3 (95 % confidence interval (CI), 166.4 - 208.2) at the end of the study. The thickness of the first to the third layer of the rectal wall, as evaluated by EUS at the beginning of the study, was significantly larger in the relapse group (mean 2.73 mm, 95 % CI 2.13 - 3.33 mm) than in the non-relapse group (1.79 mm; 1.56 - 1.99 mm; P = 0.0001).

CONCLUSIONS

Catheter probe-assisted endoluminal ultrasonography may predict the occurrence of relapse of ulcerative colitis.

Early results of coronary grafting using ultrasonically skeletonized internal thoracic arteries

BACKGROUND

We have developed an ultrasonic complete skeletonization technique for obtaining internal thoracic artery (ITA) grafts and have used this method clinically since January 1998. In this report, we discuss the early results of bilateral ITA grafts obtained with our method.

METHODS

We studied 200 consecutive patients who underwent coronary artery bypass grafting using ITAs obtained by this technique. Angiography of the grafts was performed in 188 patients (94%) within 1 month after coronary artery bypass grafting.

RESULTS

The ITA grafts were about 4 cm longer than pedicled ITA grafts. The free flow through the grafts was at least 30% higher than through pedicled ITAs. The early patency rate determined by postoperative angiography of the grafts was 99.7% for left ITAs and 100% for right ITAs. No patient required postoperative intervention or repeated surgery.

CONCLUSIONS

Ultrasonic complete skeletonization increases the effective length of ITA bypasses, improves free flow through the bypasses, and it is less invasive than conventional pedicled harvesting. These excellent early results indicate that this technique is a straightforward, safe, less invasive, and optimal method for obtaining ITA bypass grafts.

Dynamic localization and function of Bni1p at the sites of directed growth in Saccharomyces cerevisiae

Formin homology (FH) proteins are implicated in cell polarization and cytokinesis through actin organization. There are two FH proteins in the yeast Saccharomyces cerevisiae, Bni1p and Bnr1p. Bni1p physically interacts with Rho family small G proteins (Rho1p and Cdc42p), actin, two actin-binding proteins (profilin and Bud6p), and a polarity protein (Spa2p). Here we analyzed the in vivo localization of Bni1p by using a time-lapse imaging system and investigated the regulatory mechanisms of Bni1p localization and function in relation to these interacting proteins. Bni1p fused with green fluorescent protein localized to the sites of cell growth throughout the cell cycle. In a small-budded cell, Bni1p moved along the bud cortex. This dynamic localization of Bni1p coincided with the apparent site of bud growth. A bni1-disrupted cell showed a defect in directed growth to the pre-bud site and to the bud tip (apical growth), causing its abnormally spherical cell shape and thick bud neck. Bni1p localization at the bud tips was absolutely dependent on Cdc42p, largely dependent on Spa2p and actin filaments, and partly dependent on Bud6p, but scarcely dependent on polarized cortical actin patches or Rho1p. These results indicate that Bni1p regulates polarized growth within the bud through its unique and dynamic pattern of localization, dependent on multiple factors, including Cdc42p, Spa2p, Bud6p, and the actin cytoskeleton.

The Hecht vault performed at the 1995 World Gymnastics Championships: deterministic model and judges' scores

The aim of this study was to determine the mechanical variables that govern success of the Hecht vault. The participants were 122 male gymnasts from 30 countries performing the vault at the 1995 World Gymnastics Championships. The vaults were filmed using a Photosonics 16-mm motion picture camera operating at 100 Hz. Approximately 80 frames were digitized for each vault analysed. The method of Hay and Reid was used to develop a theoretical model to identify the mechanical and physical variables that determine linear and angular motions of the vault. Correlational analysis was used to establish the strength of the relationship between the causal mechanical variables identified in the model and the judges' scores. Significant correlations (P < 0.005) indicated that the following were important determinants of success: large horizontal and vertical velocities at take-off from the board and the horse; large vertical and angular distances of pre-flight; large vertical impulses of high force and short duration exerted on the horse and the resulting large changes in vertical velocity on the horse; and large horizontal and vertical distances and long times of post-flight. Of the 18 significant variables identified in the present study, the angular distance of pre- and post-flights, the horizontal velocity and angular momentum at take-off from the horse, and the average moment of inertia and duration of post-flight collectively accounted for 57% of the variation in the judges' scores.

[Management of coronary artery disease combined with aortic stenosis: how to do with mild aortic stenosis]

A total of fourteen patients with combined operation of coronary artery bypass grafting (CABG) and aortic valve replacement (AVR) for coronary artery disease (CAD) and aortic stenosis (AS) were reviewed to evaluate the indication of the combined operation. Preoperative pressure gradient across the valve and effective orifice area were 21-89 mmHg (mean 64 mmHg), 0.5-1.9 cm2 (mean 0.92 cm2), respectively. The extent of CAD was 1-3 (mean 2.0). Fractional shortening (%FS) ranged from 13% to 43% with mean value of 28%. All patients underwent CABG and AVR. The number of grafts was 1-4 (mean 2.3) with internal thoracic artery used in 7 cases. Mechanical valves were employed for all patients except 1 case with cerebral aneurysm. There was no operative death, although low output syndrome developed in 2 cases. One had poor left ventricular function preoperatively, and the other was emergency case. Fractional shortening improved postoperatively even in two cases with preoperative %FS less than 20%, and all grafts were patent on postoperative coronary angiography. The event-free survival was 100% during 32 months of mean follow-up. Combined AVR with CABG is recommended to avoid risky secondary operation in patients of CAD and AS, even if one of which is relatively mild, because of the fact that operative and late results of the combined surgery are satisfactory.

Coronary artery bypass grafting using the "Super Pulse" dynamic pulsatile cardiopulmonary bypass device in patients with cerebrovascular occlusive disease

Patients with coronary disease complicated by severe carotid or intracranial arterial stenosis underwent coronary artery bypass graft surgery (CABG) using a novel method of dynamic pulsatile cardiopulmonary bypass (Super Pulse CPB). The Super Pulse technique can maintain the systolic pressure and systolic-diastolic amplitude in such a way that they mimic the physiologic circulation. Forty-five patients (33 males and 12 females, mean age 65.1 years) with coronary disease who had a greater than 75% stenosis of the carotid or intracranial arteries were evaluated. Evaluation was performed for the following 3 groups: 8 patients with conventional pulsatile CPB (Group I), 8 patients with conventional pulsatile CPB plus intraaortic balloon pumping (Group II), and 29 patients with Super Pulse CPB. Maximum, minimum, and mean perfusion pressures during CPB were 112.7, 53.6, and 76.9 mmHg (integrated mean), respectively, in Group III. The systolic-diastolic amplitude was significantly better than for Group I and similar to baseline pressures. No patients in Group II or Group III developed perioperative cerebral disorders or myocardial infarction, while in Group I perioperative cerebral disorders developed in 3 patients, myocardial infarction occurred in 2 patients, and 2 patients died during hospitalization. The initial performance of the Super Pulse CPB indicates excellent safety, and is useful for patients with co-morbid cerebral arterial disease.

Retrograde cerebral perfusion versus selective cerebral perfusion as evaluated by cerebral oxygen saturation during aortic arch reconstruction

BACKGROUND

Time limits for neuroprotection by retrograde cerebral perfusion (RCP) and selective cerebral perfusion (SCP) in aortic arch aneurysm repair or dissection are undergoing definition.

METHODS

Using near-infrared optical spectroscopy, changes in regional cerebrovascular oxygen saturation (rSO2) were compared between the two perfusion methods.

RESULTS

Immediately before cardiopulmonary bypass, baseline rSO2 was 63.9%+/-6.9% for the RCP and 66.1%+/-5.3% for the SCP group (no significant difference). As patients were core-cooled to 20 degrees C, rSO2 increased to 73.1%+/-8.8% and 74.1%+/-7.9% in the RCP and SCP groups, respectively. With circulatory arrest, rSO2 suddenly decreased. After starting cerebral perfusion, rSO2 returned to prearrest values in the SCP group but continued decreasing steadily in the RCP group, to levels below baseline after about 25 minutes. At the end of perfusion, rSO2 was 57.4%+/-12.2% for the RCP group and 71.7%+/-6.9% for the SCP group, and the ratio of rSO2 to baseline value was 0.89 for RCP and 1.08 for SCP despite a shorter brain perfusion time for RCP (38.8+/-18.0 versus 103.3+/-43.3 minutes). Three of 5 patients whose ratios of rSO2 to baseline at the end of brain protection were 0.7 or less had neurologic deficits.

CONCLUSIONS

Although SCP showed no clinically important time limitation, rSO2 continued to decrease with time during RCP. An rSO2 ratio less than 0.7 could represent a critical lower limit.

The effect of direct lidocaine injection into the clamped aortic segment on the spinal evoked potential: early diagnosis for spinal cord ischemia

PURPOSE

The aim of this study was to identify a method to determine whether segmental artery reconstruction was indicated during aortic clamping.

METHOD

Spinal cord evoked potential (SCEP) and regional spinal blood flow were studied in 24 adult dogs. Using the left heart bypass technique, aortic clamping divided the aorta into thoracic, abdominal, and terminal segments. After the occlusion of the descending aorta and discontinuation of the perfusion to the abdominal segment, animals were assigned to four groups: no treatment with perfusion to the terminal aorta (group IA), no treatment with cessation of bypass (group IB), 5% lidocaine administration (5 mg/kg) into the abdominal segment with perfusion to the terminal aorta (group IIA), and lidocaine administration with cessation of bypass (group IIB).

RESULTS

Cessation of bypass reduced spinal blood flow and SCEP amplitude. Lidocaine injection allowed for a significant rapid decrease in SCEP amplitude in group IIB compared with group IB (24.2% +/- 13.4% versus 92.3% +/- 33.2%; p = 0.0039). The degree of spinal blood supply was reflected immediately in the magnitude of SCEP amplitude change by the direct lidocaine injection. (group IB versus group IIB; p = 0.023).

CONCLUSION

The direct injection of lidocaine into the clamped aorta results in a rapidly change in SCEP in the threat of ischemia and can be used to make an early detection of the segmental arteries perfusing to the spinal cord.

Emergency percutaneous cardiopulmonary bypass support for acute myocardial infarction

We assessed the efficacy of emergency percutaneous cardiopulmonary bypass support (PCPS) in the treatment of patients with acute myocardial infarction complicated by cardiogenic shock. Emergency PCPS was instituted in 21 consecutive patients beginning in 1991. After the stabilization of the hemodynamics, coronary reperfusion was performed by means of coronary artery bypass grafting or percutaneous transluminal coronary angioplasty. Of the seven patients with acute myocardial infarction involving either the left main or two-vessel territories, five survived more than 1 month, but only one patient remained alive and well after 20 months. The main cause of death for this group was low output syndrome. Four of 12 patients with acute left main trunkal occlusion in the catheter laboratory survived and showed a preserved cardiac function (mean followup 28.5 months). The main cause of death for this group was brain damage. Two patients with single-vessel territory acute myocardial infarction underwent PCPS to treat refractory ventricular fibrillation. Both patients were still alive and well at a 12-month followup. Percutaneous cardiopulmonary bypass support successfully stabilized the hemodynamics, allowing time to perform revascularization for all three groups of patients with life-threatening acute myocardial infarction. Recanalization was nevertheless unable to salvage the damaged myocardium in cases of prolonged ischemic time.

Surgical results for thoraco-abdominal aneurysm by modified DeBakey method using centrifugal biopump and renal cryopreservation

BACKGROUND

In this paper, we report the surgical results of our DeBakey and Crawford combined method.

METHODS

From 1985 to 1995, 22 consecutive patients with thoraco-abdominal aneurysms underwent a modified DeBakey and Crawford combined procedure to minimize the ischemic time for the spinal cord and visceral organs. The extent of aneurysm as classified by Crawford was as follows: Group I, 12; Group II, 4, Group III, 3; Group IV, 3. The etiology of the aneurysm was atherosclerosis in 19, cystic medial necrosis in 2, and aortitis in 1. The aneurysm was approached through the spiral opening method. First, end-to-side distal anastomosis was performed above the bifurcation under partial aortic clamping, and this was followed by proximal anastomosis. During the end-to-end proximal anastomosis, a Gott shunt tube or heparinless left heart bypass was used. In two patients, left renal artery had been previously reconstructed by a saphenous vein graft extending from the left common iliac artery. Then aneurysm was opened, and the right renal artery and superiors mesenteric artery were perfused with cold blood. In two patients, partial cardiopulmonary bypass and selective perfusion were performed. In eight patients, renal artery, celiac artery, superior mesenteric artery, and intercostal artery were reconstructed with a branch graft.

RESULTS

No patient died within 30 days of surgery, however, one patient died of acute myocardial infarction (POD 54) and another of ventricular fibrillation during hemodialysis (POD 60). Postoperative complications included paraplegia, and renal failure requiring dialysis each in two patients. Postoperative angiography revealed 18/19 (94.7%) of grafts were patent.

CONCLUSIONS

In conclusion, by using different techniques for spinal cord and visceral protection, including the Gott shunt, Biomedicus pump, renal cryopreservation, and separate revascularization of viscera and intercostal arteries, good results could be obtained.

Rupture of a dissecting aneurysm into the superior vena cava in Marfan's syndrome

Aneurysmal dilatation of the aorta with subsequent dissection or rupture occurs frequently in patients with Marfan's syndrome. These complications are among the major causes of death. We report the case of a 51-year-old man with annulo-aortic ectasia in Marfan's syndrome. Acute aortic dissection and rupture into the superior vena cava occurred 8 years after aortic valve replacement. The preoperative diagnosis was made by right heart catheterization and computed tomography. A markedly increased left-to-right shunt occurred with rapid enlargement of the fistula due to the fragility of the aortic wall characteristic of Marfan's syndrome. Postmortem examination demonstrated severe medial necrosis with rupture of the aortic wall into the superior vena cava which was adherent to the suture line of the aortotomy from the previous surgery. Type A aortic dissection with severe congestive heart failure strongly suggested rupture into the pulmonary circulation.

Single lung transplantation for canine pulmonary hypertension

BACKGROUND

In spite of recent reports of the clinical application of single lung transplantation for pulmonary hypertension, there is little underlying experimental data because of the lack of a reliable animal pulmonary hypertensive transplant model. We have established a pulmonary hypertensive model in beagles with dehydromonocrotaline and have been able to measure cardiopulmonary hemodynamics accurately and use circulatory assists during procedures. The purpose of this study was to determine whether single lung transplantation could be performed after the protocol of clinical procedure.

METHODS AND RESULTS

In six control dogs, allografting was successfully completed without cardiopulmonary bypass. Because one pulmonary hypertensive recipient dog died of right ventricular failure during the procedure without cardiopulmonary bypass, we used bypass for allografting in five pulmonary hypertensive dogs. Cardiopulmonary bypass lowered pulmonary artery pressure, allowing pulmonary arterial clamping and avoiding right ventricular overload. All pulmonary hypertensive dogs undergoing bypass were successfully weaned from bypass, indicating a good hemodynamic response to transplantation. In pulmonary hypertensive dogs, transplantation resulted in significant decreases in systolic pulmonary artery pressure and pulmonary vascular resistance, and a significant increase in blood flow to the graft lung, whereas in controls the results were the reverse.

CONCLUSIONS

Thus we were able to show that hemodynamics improved after single lung transplantation with cardiopulmonary bypass in a new pulmonary hypertensive animal model. These relatively larger animals are valuable for further studies of single, double, bilateral, and heart-lung transplantation for pulmonary hypertension.

[A case report of an infective endocarditis caused by methicillin-resistant Staphylococcus aureus with successful mitral valve replacement]

We report a case of successful mitral valve replacement performed on the patient who is an infective endocarditis due to MRSA. She was 27-year-old female and treated by antibiotics medication because of remittent fever two years ago. On August 1995, cerebral infarction occurred and she was pointed out endocarditis. After high fever continued, blood cultures demonstrated MRSA. Furthermore, echocardiography showed vegetation on posterior mitral valve leaflet and moderate mitral regurgitation so, mitral valve replacement with a S.J.M. 25 mm performed to control MRSA sepsis condition. During operation, we used VCM 2 g into the extracorporeal circulation and after operation 0.5 g intravenously every 6 hours. Two weeks later we changed antibiotics to FOM, Viccillin and ABK according to the result of minimum inhibitory concentration (MIC) obtained through blood culture. The patient was discharged on the 44 th postoperative day because of her uneventful postoperative course.

[Rupture of the aneurysm of the sinus valsalva: thirteen years after the initial diagnosis]

We report a case of an unruptured aneurysm of the sinus Valsalva (URASV) which was followed thirteen years without surgery. A 47-year-old female had a heart murmur detected at age 34 during pregnancy. Though an URASV was diagnosed, because the aneurysm was less than 1 cm in size, no surgery was advised at that time. Thirteen years later, she gradually noticed of increased heart beats and also dyspnea on exertion. Echocardiogram showed an aneurysm of the sinus Valsalva ruptured to the RV cavity. In June 1994, resection of the aneurysm was performed. One year later, the patient was asymptomatic. This may be the second longest long-term follow-up report of the patient with an unruptured aneurysm of the sinus Valsalva.

Counterproductive effects of sodium bicarbonate in diabetic ketoacidosis

Although a growing body of evidence supports that alkali therapy in diabetic ketoacidosis (DKA) might be counterproductive, our knowledge about the consequences of this treatment on ketone metabolism is limited. Consequently, we performed clinical and animal studies to further examine this topic. The clinical studies assessed seven patients with DKA treated with continuous insulin infusion at a low dosage. Three of them also received sodium bicarbonate (NaHCO3), whereas the remaining four acted as controls. The group receiving NaHCO3 showed a 6-h delay in the improvement of ketosis as compared with controls. In addition, there was an increase in acetoacetate (AcAc) levels during alkali administration, followed by an increase in 3-hydroxybutyrate (3-OHB) level after its completion. Significant differences were not found between groups in the response of plasma glucose to the overall therapy. The animal study examined the effects of a NaHCO3-rich perfusate on the hepatic production of ketones with the in situ rat-liver preparation. Alkali loading resulted in an immediate increase in the AcAc level followed by increases in both the 3-OHB level and the 3-OHB/AcAc ratio after its completion. Hepatic ketogenesis increased even further, to about twice the basal level, after termination of the NaHCO3 loading. This investigation confirms that alkali administration augments ketone production and unravels an effect of bicarbonate infusion that promotes a selective build up of AcAc in body fluids. The data support that alkali therapy in DKA has nonsaltuary effects in the metabolism and plasma levels of ketones.

Acute left atrial thrombus causing cardiogenic shock following mitral valve replacement: report of a case

We report herein the rare case of a 53-year-old woman who developed cardiogenic shock due to an acute left atrial thrombus following replacement of the mitral valve. A definitive diagnosis was not able to be made using precordial echocardiography because of the broad, flat shape of the thrombus; however, transesophageal echocardiography imaged the thrombus in detail. The patient was initially stabilized by percutaneous cardiopulmonary support after which a thrombectomy was successfully performed.

[A case of mitral valvuloplasty with concomitant CABG in an aged patient]

A 79-year-old man was referred to our hospital complaining of the manifestation of mild heart failure. Echo cardiography and LV gram showed sever mitral regurgitation by the prolapse of posterior leaflet. CAG revealed coronary artery disease affected two vessels (LAD and RCA) without symptoms. Quadrangular resection of posterior leaflet (McGoon's method) without annuloplasty and concomitant single CABG to the LAD using a saphenous vein were performed. Postoperative course was satisfactory and the manifestation of heart failure was diminished. Mitral valvuloplasty with concomitant CABG may be a safe and effective procedure in the treatment of aged patients.

Pharmacologic intervention for ischemic brain edema after retrograde cerebral perfusion

Retrograde cerebral perfusion has recently been the focus of interest as a simple new technique of brain protection during aortic arch operations. We undertook the experimental protocol of 120 minutes of retrograde cerebral perfusion followed by antegrade reperfusion. Eighteen mongrel dogs were used. Retrograde cerebral perfusion was maintained at a flow rate of 150 to 250 ml/min to keep the perfusion pressure from 15 to 25 mm Hg. Animals were divided into three groups as follows: in group I, no treatment was received during and after retrograde cerebral perfusion; in group II, mannitol (2 gm/kg) was administered before cardiopulmonary bypass was restarted; and in group III, antivasospastic substance (1,2-bis nicotinamido]-propane) was continuously injected during and after retrograde cerebral perfusion (1 mg/kg per minute). Cerebral blood flow decreased during retrograde cerebral perfusion in all three groups. Cerebrovascular resistance showed marked increases 30 and 60 minutes after cardiopulmonary bypass was restarted in group I compared with the values in groups II and III (group I: 3.35 +/- 0.73 and 5.00 +/- 1.57 mm Hg/ml per 100 gm per minute; group II: 1.30 +/- 0.33 and 1.03 +/- 0.17 mm Hg/ml per 100 gm per minute; group III: 1.24 +/- 0.41 and 0.98 +/- 0.24 mm Hg/ml per 100 gm per minute). The oxygen extraction level was reduced by cooling, but it rose to a higher level as a result of significant desaturation of returned blood even in deep hypothermia during retrograde cerebral perfusion. Both cerebral metabolic rate of oxygen and cerebral metabolic rate of glucose remained at low levels during retrograde cerebral perfusion. Ratios of cerebral blood flow to cerebral metabolic rate of oxygen and cerebral blood flow to cerebral metabolic rate of glucose were markedly reduced during retrograde cerebral perfusion. Intracranial pressure showed significant increases 30 and 60 minutes after cardiopulmonary bypass was restarted in group I compared with values in group II or group III (group I: 22.7 +/- 2.8 and 20.6 +/- 5.1 mm Hg; group II: 6.3 +/- 1.8 and 5.3 +/- 1.3 mm Hg; group III: 4.2 +/- 1.7 and 7.7 +/- 2.8 mm Hg). Water content of the brain tissue in group I (77.54% +/- 0.29%) was significantly higher than that in group II (74.71% +/- 0.76%) or group III (74.14% +/- 0.48%). These data suggest that the supply of oxygen or glucose by retrograde cerebral perfusion is not enough to maintain sufficient cerebral metabolism, which may cause brain edema during antegrade reperfusion.(ABSTRACT TRUNCATED AT 400 WORDS)

[Simultaneous operations for both the repair of the aortic arch aneurysm and repeated CABG]

A 73-year-old female complaining of left thoracic pain was referred to our hospital. In 1988, she had the first CABG of the left circumflex coronary artery (CX) and right coronary artery. On admission in April 1994, chest X-ray and CT scan revealed a saccular aortic aneurysm, 5 x 5 cm in size, extending to the distal to the left subclavian artery. Coronary arteriography showed a patency of the CX graft, but 99% stenosis of the proximal left anterior descending branch (LAD) with delayed opacification. After the repeated median sternotomy, cardiac arrest was achieved with the aortic cross clamping and St. Thomas Hospital solution infusion. CABG to the LAD branch using a saphenous vein was accomplished. Following this, the replacement of the aortic aneurysmal lesion with a prosthetic graft was performed under the selective cerebral perfusion with deep hypothermia. Proximal anastomosis of the vein graft was completed during a rewarming period. The operation was performed without complications. Postoperative course was satisfactory except a few minor transient complications such as athelectasis of the left upper lobe and the intra-thoracic hematoma. After one month's hospitalization, she was discharged, and currently (six months postoperative) remains asymptomatic.

Isolation of rat TATA factor as an active 75kDa protein complex

A general transcription factor TFIID was purified from rat liver by a sequential column chromatography including organomercurial Sepharose and Sephacryl S-200 chromatographies, which were developed with an acidic buffer (pH5.5). Analyses by SDS-polyacrylamide gel electrophoresis, assay of eluants after renaturation, and immunoblotting showed that isolated TATA factor is an active 75kDa protein complex which contains 36kDa TATA-binding protein.

Partial sequencing of two forms of concanavalin A-unbound collagenase inhibitor from bovine gingiva

Three forms of collagenase inhibitor, one ConA-bound and two ConA-unbound, were extensively purified from bovine gingiva by sequential column chromatography. Analysis by sodium dodecyl sulphate-polyacrylamide gel electrophoresis revealed that inhibitory activity resides in proteins with M(r) of 26000-28000 and 22000 for ConA-bound and two ConA-unbound inhibitors, respectively. Of these, two ConA-unbound inhibitors were partially sequenced in the first 12 amino acids and found to have an identical sequence. The NH2-terminal sequence had 100% identity with TIMP-2 or MI.

[A case of aortic valve stenosis and regurgitation with idiopathic thrombocytopenic purpura]

A patient of aortic valvular disease with idiopathic thrombocytopenic purpura underwent aortic valvular replacement. We report a preventive measure against the intra and postoperative bleeding. The patient was a 67-year-old man. He was diagnosed as aortic valvular stenosis with regurgitation. There was no abnormal data about the coagulation test. Thrombocyte count was 8.2 x 10(4)/mm3, but thrombocytopenic life span had shortened 3.8 days. So, we used gamma-globulin 400 mg/kg/day for 5 days before the day of operation and infused blood platelets on the day of operation. There was no problem intra and postoperative period. On the 14th postoperative day thrombocyte count increased to 22.9 x 10(4)/mm3, and thrombocytopenic life span returned to normal range (7.6 days). But on the 45th day of postoperation, thrombocyte count decreased to 11.0 x 10(4)/mm3. We think that many gamma-globulin medication is a useful method to prevent intra and postoperative bleeding resulting from idiopathic thrombocytopenic purpura.

[A case of surgical repair of aortic dissection associated with tear of the right coronary artery]

A 39-year-old female with dissecting aortic aneurysm of DeBakey type I, underwent replacement of the ascending aorta. We found that the right coronary artery originated just distally from the left sinus of Valsalva, run transversally in the aortic wall. Because the entry of dissection occurred at the right coronary artery, it was torn longitudinally. Aorto (graft)-rt. coronary bypass grafting was performed. She had no ischemic heart symptoms postoperatively. It is supposed that the dissecting aortic aneurysm was caused by the anomalous origin of the right coronary artery.

[A case of bilateral multiple pulmonary arteriovenous fistula treated by the right fistula plication and resection of the left lingual lobe with use of microwave tissue coagulator (MTC)]

A 53-year-old man with the history of brain abscess and multiple cerebral arterio-venous malformations underwent the staged operation for bilateral multiple pulmonary arterio-venous fistulas (PAVF). Right fistula plication and the resection of the left lingular lobe using MTC were performed through posterolateral thoracotomy. Postoperatively, the patient showed the right residual fistula, but, he has been doing well without PAVF complications such as polycythemia and hypoxemia. In conclusion, 1) PAVF with central nervous system complications should be treated aggressively either by surgery or by embolization. 2) MTC was useful for the resection of the lung because of no air leak and bleeding coming from the resected section.

[Thoracic duct cyst--a case report]

A case of thoracic duct cyst was reported. The patient, 72 year old man, was admitted with chief complaint of dysphagia. Chest X-ray film demonstrated an ovoid mass at the right upper mediastinum and the esophagus pressed by the tumor to the right. CT scan showed a round tumor with obscure margin located at the right upper mediastinum. Other laboratory data were almost within normal limits. Thoracotomy was performed on March 26, 1987 under diagnosis of leiomyoma of the esophagus. A fluid containing cyst covered with pleura was found at the upper mediastinum. The tumor was connected to the thoracic duct at its upper and lower portion. The cyst was isolated by sharp and blunt dissection without difficulties and removed. The cyst measured 7.5 X 4.5 X 4.5 cm and contained chyle. Pathological examination revealed no evidence of malignancy. Postoperative course of this patient was uneventful, and dysphagia was disappeared.

[Production of prostaglandin E2 by polymorphonuclear neutrophils isolated from gingival crevicular fluid and peripheral blood of dogs in periodontal health and disease]

We examined PGE2 synthesis using inflamed and non-inflamed GCF PMNs and PB PMNs in the presence and absence of certain stimulators. The basal levels of PGE2 release from GCF PMNs isolated from ligature-induced gingival sulcus with a GI value over 2.2 were significantly lower than those from GCF PMNs isolated from sham operated sites with a GI value below 2.1. Levels were comparable to those from PB PMNs isolated at each experimental period, indicating that the amount of PGE2 synthesized by GCF PMNs is not correlated exactly with the severity of periodontitis. Calcium ionophore A23187 stimulated PGE2 synthesis by all PMN preparations. When compared to those with inflamed and non-inflamed GCF PMNs, stimulation was higher with PB PMNs. However, the chemotactic factor fMLP inhibited the synthesis by inflamed and non-inflamed GCF PMNs. PGE2 synthesis by PB PMNs isolated after periodontal operation was stimulated by the drug, but those cells isolated before the operation did not respond.

[The causes of prolonged postoperative respiratory care in mitral valve disease with a giant left atrium]

Whether a giant left atrium in mitral valve disease itself prolongs postoperative respiratory care or does not is an important problem. We investigated it in 39 patients who underwent MVR without plication of the left atrium. A giant left atrium (GLA) was defined when CT-LA volume exceeded 300 ml by rapid sequential CT or left atrial diameter exceeded 60 mm by echocardiography. According to this criteria, the 39 patients were divided into two groups: 18 patients of GLA group and 21 of non-GLA group. Eight GLA (44%) and 11 non-GLA patients (52%) needed postoperative respiratory care with intratracheal intubation for more than 24 hours. Four GLA (22%) and 2 non-GLA patients (9.5%) needed reintubation. There was no significant difference between the two groups concerning the duration of postoperative respiratory care and the frequency of reintubation. The reintubated patients had three prominent preoperative clinical profiles, such as poor general condition, poor cardiac function and poor respiratory function. Consequently, it is concluded that in mitral valve disease with a GLA the prolongation of postoperative respiratory care is largely due to poor cardiac and respiratory function rather than to the compression to the bronchus by a GLA.

[A case of Marfan syndrome with recurrent bilateral pneumothorax and anuloaortic ectasia]

A 17-year-old male patient with Marfan syndrome was admitted due to recurrent bilateral pneumothorax which had recurred totally 11 times during the past 3 years. For the treatment of obstinately continuing right pneumothorax resection of bullae in combination with pleuropexy using OK 432 was effective. Two months thereafter Bentall operation with a composite graft consisting of a woven Dacron tube and a Björk-Shiley 27 mm aortic valve prosthesis was performed for his anuloartic ectasia. Left pneumothorax recurred 2 weeks after Bentall operation. But it was treated successfully with OK 432 injection into the left pleural cavity. Now, he is doing well as a student.

Techniques used by elite long jumpers in preparation for takeoff

It was hypothesized that some characteristics of the positions adopted by long jumpers during the final strides of the approach are significantly related to the distance of the jump, and that they are so related only by virtue of their relationships with the horizontal velocity at touchdown and/or the vertical velocity at takeoff. Trials by 20 male and 26 female long jumpers were recorded cinematographically and subsequently analyzed. The takeoff distance for the fourth-last stride, the landing distance for the last stride, and the height of the center of gravity (CG) at takeoff into the jump were significantly correlated with the distance of the jump. These three position variables were significantly related to the distance of the jump, through their relationships with the velocity of the approach and the vertical velocity of the CG at takeoff into the jump. Considered alone, they were not influential in determining the distance of the jump.

[Effective thromboexclusion for repeating bleeding tendency caused by dissecting aneurysm: a case report]

A 75-year-old woman developed general fatigue and left chest pain in October 1986, and Chest CT showed DeBakey IIIb dissecting aneurysm. During the next 8 months, she repeated abdominal pain, tarry stool and subcutaneous hemorrhage for three times and after an angiography large hematoma at puncture site appeared. The laboratory data showed the decrease in platelet and fibrinogen and the increase in FDP every time when she developed the symptoms. Because this bleeding tendency was thought to be the "local DIC" caused by dissecting aneurysm, we performed thromboexclusion on July 27, 1987. Immediately after the operation, 60 packs of platelet and 3 g of fibrinogen was transfused, then laboratory data remarkably improved and bleeding tendency disappeared. The patient died 12 days after the operation of sudden ventricular tachycardia. At autopsy, precise cause of death was not determined, but the purpose of thromboexclusion seemed to be achieved, because good thrombus formation was observed in the descending aorta and the graft was patent.

[Surgical treatment of a right atrial myxoma with pulmonary embolism]

We report on an 18-year-old man with a right atrial myxoma complicated by widespread pulmonary infarction. Under cardiopulmonary bypass, a typical gelatin-like myxoma of 65 g in weight and the segments of pulmonary infarction were simultaneously removed. From the excised lung specimens, pulmonary tissue infarction caused by myxoma acting as a blocker was recognized. This was a very rare case of myxoma complicated by pulmonary infarction, and we report here the successful removal of the right myxoma and partial pneumonectomy.

Separation and partial characterization of three forms of collagenase inhibitor from bovine gingiva

Three forms of collagenase inhibitor were isolated; one bound to Con A-Sepharose and the other two did not. The Con A-bound (Mr 38,000) and the two unbound (Mr 50,000 and 22,000) inhibitors contained about 20, 15 and 65% of the total inhibitory activity, respectively. The bound and one of the unbound (Mr 22,000) inhibitors were fairly specific for mammalian collagenase; the other unbound inhibitor was rather non-specific and also inhibited trypsin and thermolysin, but not bacterial collagenase. All the inhibitors were heat stable (90 degrees C, 30 min) and unaffected by 4-aminophenylmercuric acetate, but were inactivated by reduction and alkylation.