Practical Epoxidation of Olefins Using Air and Ubiquitous Iron-Based Fluorous Salen Complex

The epoxidation of olefins by substituting "air" for potentially harmful oxidants was achieved using an oxidation method that integrated a fluorous iron(III) salen catalyst derived from common metals and pivalaldehyde. Several aromatic disubstituted olefins were converted into their corresponding epoxides with high efficiency and quantitative yields. This reaction represents an environmentally friendly oxidation process that utilizes an abundant source of air and employs a readily available metal, iron, in the form of salen complexes, making it an environmentally conscious oxidation reaction.

P1918Comparison of the clinical outcome of pulmonary vein isolation with cryoballoon and radiofrequency ablation for atrial fibrillation with pulmonary vein triggers

Background

Pulmonary vein isolation (PVI) using radiofrequency (RF) or cryoballoon (CB) has been an established treatment for atrial fibrillation. PVI using RF is the most common method with a rather complex technique of a point-by-point tissue heating and navigation of electro-anatomical-guided mapping system, and PVI with CB is also the common method with a relatively simple technique of freezing balloon occlusion. These 2 types of ablation are comparable in terms of the efficacy of the PVI procedure.

Purpose

The data on the clinical outcome of each AF type with PV triggers has been limited. We compared the outcome of success rate between RF and CB group with respect to each AF type, and further assessed the efficacy of pulmonary vein isolation for AF patients with the origin of only PV.

Methods

A total of 3402 AF patients (age 64±11; 2463 males) underwent initial PVI from May 2009 to July 2018 (PAF: 67%, non-PAF: 37%). Radiofrequency using irrigation-tip catheter was employed to 1796 patients since May 2009 (RF-PAF: 55%, RF-non-PAF: 45%). Second-generation cryoballoon was employed to other 1606 patients since September 2014 (CB-PAF: 81%, CB-non-PAF: 19%). In CB group, PV touch-up ablation with RF was needed for 113 patients (7%) (CB-PAF: 6%, CB-non-PAF: 13%; p<0.001). After PVI, additional ablation for non-PV foci was undergone after the induction by using isoproterenol infusion and rapid atrial pacing (RF-AF: 34%, CB-AF: 32%; p=0.107).

Results

In all PAF patients, AF free survival rate was significantly superior in CB group (2-years Kaplan-Meir event rate, CB 83.2%, RF 75.2%; log-rank p<0.001). The percentage of patients with non-PV foci was almost equivalent in both group (CB 30%, RF 31%, p=0.644). And in PAF patients with only PV-foci, AF free survival rate was significantly superior in CB group (2-years Kaplan-Meir event rate, CB 85.0%, RF 78.8%; log-rank p<0.001). On the other hand, in all non-PAF patients, AF free survival rate was almost equivalent in both non-PAF group (2-years Kaplan-Meir event rate, CB 65.5%, RF-non-PAF 70.0%; log-rank p=0.9). The percentage of patients with non-PV foci was almost equivalent in both group (CB 40%, RF 39%, p=0.731), And in non-PAF patients with only PV-foci, AF free survival rate was almost equivalent in both non-PAF group (2-years Kaplan-Meir event rate, CB 69.7%, RF 73.0%; log-rank p=0.376).

Conclusions

Our study showed better outcome of PVI with CB for PAF patients with PV triggers, and indicated the non-inferiority of PVI with CB for non-PAF patients with PV triggers to PVI with RF.

P6380The impact of coronary artery disease to predict mortality and neurological outcome in post-cardiac arrest patients

Background

Some studies reported that performing coronary angiography (CAG) for patients with out-of-hospital cardiac arrest (OHCA) is effective for the prognosis and neurological outcome. However, the impact of complexity of coronary artery disease (CAD) on CAG findings has not been evaluated sufficiently.

Purpose

We sought to investigate the complexity of CAD to predict the prognosis and neurological outcome in patients with OHCA.

Methods

A total of 1382 out-of-hospital cardiac arrest patients were transferred to our critical care center, of which 252 cardiovascular arrest patients achieving the return of spontaneous circulation (ROSC) were extracted from the institutional consecutive database between January 2015 and December 2018. Among those patients, we performed CAG for 160 patients. To predict mortality in hospital and neurological outcome at 30 days, we investigated basic patients' characteristics, pre-hospital information, coronary anatomical angiographical findings.

Results

Ventricular fibrillation (VF) (P=0.001), younger age (P=0.007), pre-hospital ROSC (P<0.001) and normal coronary artery on CAG findings (P=0.014) were associated with low 30-days mortality in hospital. VF (P=0.003), younger age (P=0.004), pre-hospital ROSC (P<0.001), bystander cardiopulmonary resuscitation (CPR) (P=0.043) and normal coronary artery (P=0.001) were associated with good neurological outcome (cerebral-performance-category (CPC) =1 or 2) at 30 days. We further investigated 100 patients who had any coronary artery stenosis on CAG findings. Among these patients, 55 patients (55.0%) had multi-vessel coronary artery disease and 29 patients (29.0%) had at least a chronic total occlusion lesion. VF survivor (P=0.035), without previous history of CAD (P=0.008), pre-hospital ROSC (P=0.013), and Syntax score (P=0.002) were associated with low 30-days mortality. In multivariate analysis, Syntax score (OR 0.94; 95% confidence interval (CI) 0.88–0.99; P=0.042) was independent predictor of mortality. Bystander CPR (P=0.001), pre-hospital ROSC (P<0.001) were associated with good neurological outcome at 30 days. Bystander CPR (OR 5.92; 95% CI 2.01–17.5; P<0.001) and pre-hospital ROSC (OR 9.22; 95% CI 3.34–25.5; P<0.001) were predictive for good neurological outcome.

Conclusions

OHCA patients with any coronary stenosis had high mortality and bad neurological outcome in comparison with those who had normal coronary arteries. OHCA patients with CAD had complex lesions such as multi-vessel disease or chronic total occlusion lesions. The coronary complexity in patients with OHCA was a predictor of in-hospital 30-days mortality. However, pre-hospital care such as bystander CPR and pre-hospital ROSC were the most important to achieve good neurological outcome at 30 days in the present study.

P2266The predictor of mortality and neurological outcome in out-of-hospital cardiac arrest patients with non-ST-segment elevation

Background

The prognosis of patients with out-of-hospital cardiac arrest (OHCA) remains poor. Coronary artery disease (CAD) is the most frequent cause of OHCA. The prompt evaluation and revascularization for coronary artery in OHCA patients with ST-segment elevation are recommended because they often have CAD. However, OHCA patients without ST-segment elevation also have any coronary stenosis in the non-negligible proportion. The predictor of mortality and neurological outcome in OHCA patients with no ST-segment elevation has not been sufficiently elucidated.

Purpose

We sought to investigate the predictor of mortality and neurological outcome at 30 days in OHCA patients without ST-segment elevation.

Methods

A total of 1382 out-of-hospital cardiac arrest patients were transferred to our critical care center, of which 252 cardiovascular arrest patients achieving the return of spontaneous circulation (ROSC) were extracted from the institutional consecutive database between January 2015 and December 2018. Among those patients, 183 patients' electrocardiogram after ROSC were without ST-segment elevation. We performed coronary angiography (CAG) for 103 patients, who were eligible for final analysis. To predict mortality in hospital and neurological outcome at 30 days, we investigated basic patients' characteristics, pre-hospital information, post-hospital care.

Results

Any coronary stenosis was founded in 50 patients (48.5%). Male (P=0.007), older age (P<0.001), past history of coronary artery disease (CAD) (P=0.037) and diabetes mellitus (P=0.087) were associated with coronary artery stenosis on CAG findings. Age (OR 1.05; 95% confidence interval (CI) 1.02–1.08; P<0.001), male (OR 5.33; 95% CI 1.37–20.7; P<0.001) were independent predictors of coronary artery stenosis. Among those who had stenosis, 34 patients (68.0%) survived and 27 patients (54.0%) achieved good neurological outcome (cerebral-performance-category (CPC) =1 or 2) at 30 days. Successful revascularization by percutaneous coronary intervention (PCI) was not associated with low mortality (P=0.77). Past history of CAD (P=0.014) and high Syntax score (P=0.030) were associated with mortality. Bystander cardiopulmonary resuscitation (CPR) (P-0.021), pre-hospital ROSC (P<0.001) was more frequent in patients with good neurological outcome. Pre-hospital ROSC (OR 14.7; 95% CI 3.1–69.3; P<0.001) was independently predictive for good neurological outcome.

Conclusions

Successful PCI for OHCA patients with no ST-segment elevation was not a predictor of mortality. CAD past history and complex CAD was associated with mortality. Pre-hospital information such as pre-hospital ROSC was important to achieve good neurological outcome.

P1919The assessment of the application and the efficacy of pulmonary vein isolation with cryoballoon for non-paroxysmal atrial fibrillation

Background

Pulmonary vein isolation (PVI) using second generation cryoballoon (CB) ablation has become an established treatment for paroxysmal atrial fibrillation (PAF) patients. On the other hand, PVI with radiofrequency (RF) has been an established treatment for non-PAF patients, in addition to PAF patients.

Purpose

The data on second generation CB ablation for non-PAF patients is limited. We assessed the application of PVI with CB for non-PAF patients and compared the outcomes of success rate, radiational time, and procedural time.

Methods

A total of 2632 AF patients (age 64±10; 1873 males) underwent initial PVI from September 2014 to June 2018. Second-generation CB was employed to 1587 patients (CB-PAF: 80%, CB-non-PAF: 20%) and RF using irrigation-tip catheter was employed to other 1045 patients (RF-PAF: 40%, RF-non-PAF: 60%). In CB group, PV touch-up ablation with RF was needed for 113 patients (7%) (CB-PAF: 6%, CB-non-PAF: 13%; p<0.001). After PVI, additional ablation for non-PV foci was undergone after the induction by using ISP infusion and rapid atrial pacing.

Results

AF free survival rate was almost equivalent in both non-PAF group (2-years Kaplan-Meir event rate, CB-non-PAF 66.3%, RF-non-PAF 69.8%; log-rank p=0.297). There was significantly difference in procedural time (CB-non-PAF 132±56min, RF-non-PAF: 189±52min, p<0.001), and radiation time (CB-non-PAF: 47±40min, RF-non-PAF: 75±31min, p<0.001). The percentage of patients with non-PV foci was significantly higher in CB group (CB-non-PAF 41%, RF-non-PAF 54%, p<0.001), and after excluding the patients with non-PV foci, AF free survival rate was almost equivalent in both group (2-years Kaplan-Meier event rate, CB-non-PAF 75.4%, RF-non-PAF 78.8%; log-rank p=0.577). On the other hand, in patients in CB, AF free survival rate was significantly superior in PAF group (2-years Kaplan-Meir event rate, CB-PAF 83.3%, CB-non-PAF 65.2%; log-rank p<0.001). There was significantly difference in procedural time (CB-PAF: 117±47min, CB-non-PAF: 132±56min, p<0.001), and radiation time (CB-PAF: 38±22min, CB-non-PAF: 46±27min, p<0.001). The percentage of patients with non-PV foci was significantly higher in non-PAF group (CB-PAF 30%, CB-non-PAF 41%, p<0.001), and after excluding the patients with non-PV foci, AF free survival rate was also significantly superior in PAF group (2-years Kaplan-Meier event rate, CB-PAF 85.1%, CB-non-PAF 69.8%; log-rank p<0.001).

Conclusions

For non-PAF patients with PV triggers, PVI with CB might be non-inferior to PVI with RF. Our study showed the efficacy of CB in terms of the shortening of procedural time, and the reduction of radiational exposure. PVI with CB for non-PAF patients was inferior to that for PAF patients.

Simultaneous supraventricular tachycardias in both fetuses of a twin gestation

BACKGROUND

Fetal supraventricular tachycardia confers an increased risk of cardiac failure, hydrops, and eventual intrauterine death. Although protocols for prenatal anti-arrhythmic treatment are now well established, few published reports discuss this condition in the setting of multiple pregnancies.

CASE REPORT

A 20-year-old primigravida woman with a twin pregnancy presented at 31 weeks of gestation for routine obstetrical check-up which revealed simultaneous supraventricular tachycardia in both fetuses. She was treated with oral digoxin, resulting in successful cardioversion in both of the fetuses, which was maintained until they were delivered by caesarian section at 38 weeks gestation. However, several hours after birth, tachyarrhythmias recurred in each of the infants. Combined disopyramide therapy with digoxin was necessary to control their heart rates.

CONCLUSION

The treatment of arrhythmia in fetuses of a multiple gestation presents unique issues, particularly when diagnosed prior to fetal lung maturity.

[Familial aortic dissection; cases involving a father, mother, and son]

The occurrence of familial aortic dissection is rare in cases that are not linked to Marfan syndrome. We report the 3 cases of acute aortic dissection, involving both parents and their son. Case 1 (father case): 79-year-old male visited a nearby doctor complaining of severe chest and back pain. He was diagnosed as acute aortic dissection (Stanford type A). An emergency operation was carried out and he had an artificial vascular replacement of ascending aorta and arch portion. Case 2 (mother case): 73-year-old female was treated for hypertension. Suddenly, she had a terrible epigastralgia and back pain. The contrast enhanced chest computed tomography (CT) revealed an acute aortic dissection (Stanford type A). The ascending aortic aneurysm ruptured in the ambulance while she was transferred to our hospital. She arrived at our hospital after cardiac and respiratory arrest. We attempted to perform cardiac massage, but we could not bring her back to life. Case 3 (son case): 48-year-old male was transferred to our hospital diagnosed with acute aortic dissection (Stanford type A). The ascending aorta replacement was performed on the same day. We were able to save cases 1 and 3 by performing surgery. Aortic dissection is thought to be the disease of medial degeneration. Hereditary links to aortic dissection are not well understood, with the exception of Marfan syndrome cases. The investigation of genetic mechanisms related to aortic dissection will be expected in the future.

[A difficult case of antiphospholipid syndrome with repeated restenosis of coronary artery and grafts]

A 65-year-old man complained of exertional angina. Coronary angiography revealed 99% stenosis in the left anterior descending artery (LAD). He underwent percutaneous transluminal coronary angioplasty (PTCA) and stenting. Repeat angiography demonstrated restenosis of the previous PTCA and stenting site. He underwent coronary artery bypass grafting (CABG) with placement of the left internal thoracic artery (LITA) to LAD. Chest discomfort and V1-V3 ST elevation appeared on the first post operative day. Coronary angiography revealed occlusion of the LITA graft. He underwent re-operation. Because the radial artery was severely sclerotic, the great saphenous vein was used for the graft. Two weeks later, he began to show edema in the left lower extremity. Echoangiogram showed occlusion of the left deep vein with thrombus. He tested positive for anticardiolipin IgG and IgM antibodies. Eighteen months after re-operation, he had recurrent chest discomfort on exertion. Coronary angiography revealed 90% stenosis of the anastomosis (SVG-LAD). A second re-operation was performed. We used the right internal thoracic artery (RITA) for the graft. The postoperative angiography showed patent graft. The patient has been doing well without any complications.

Evaluation of mitogen-induced responses in marine mammal and human lymphocytes by in-vitro exposure of butyltins and non-ortho coplanar PCBs

The effects of exposure to butyltin compounds (BTs: tributyltin; TBT, dibutyltin; DBT and monobutyltin; MBT) and non-ortho coplanar PCBs (IUPAC 77, 126 and 169) on marine mammals and human lymphocyte were evaluated. Peripheral blood mononuclear cells (PBMCs) isolated from Dall's porpoises (Phocoenoides dalli), bottlenose dolphins (Tursiops truncatus), a California sealion (Zalophus californianus), a larga seal (Phocoa largha) and humans (Homo sapiens) were exposed at varying concentrations of BTs and coplanar PCBs. Concanavalin A (Con A)-stimulated mitogenesis found significantly suppressed (P<0.01) when the cells were exposed at 300 nM (89 ng/ml) of TBT and 330 nM of DBT (77 ng/ml), while MBT showed little cytotoxicity at treatment levels of up to 3,600 nM (620 ng/ml). BTs concentrations in the liver of Dall's porpoises from Japanese coastal waters ranged between 81-450 ng/g for TBT and 200-1,100 ng/g (wet wt.) for DBTs, which is greater than the cytotoxic levels registered in this study. In contrast, non-ortho coplanar PCBs did not suppress cell proliferation at concentrations of up to 30 nM (10 ng/ml). The residue levels of coplanar PCBs in the blubber of Dall's porpoises were 0.12-1.3 ng/g, which were one order of lower than those levels that do cell proliferation. When cells were exposed to a mixture of TBT/DBTand coplanar PCBs, the proliferation was significantly reduced to 33 nM DBT plus 34 nM CB-77 and 33 nM DBT plus 28 nM CB-169 mixtures, respectively. The investigations relating the contaminant-induced immunosuppression in marine mammals have been focused on persistent organochlorines such as PCBs. pesticides and dioxin compounds. However, this study suggested the possibility of BTs could also pose a serious threat to the immune functions in free-ranging marine mammals and humans.

[Two cases of stent graft repair for thoracic aortic dissection: usefulness of three-dimensional computed tomogram]

We carried out stent graft repair in two patients with Stanford type B thoracic aortic dissection. A 51-year-old male was admitted to our hospital because of thoracic aortic dissection. Chest CT revealed an aneurysm of the distal aortic arch. The entry was pointed out 1 cm distal from the take off of the left subclavian artery in three-dimensional CT (3 D-CT). He was treated with a Gianturco stent which was anchored into the 30 mm Hemashield graft under selective cerebral perfusion. Another case was a 72-year-old male with a descending aortic aneurysm. 3 D-CT showed that the entry existed 4 cm proximal to the celiac artery. We performed transluminal implantation of the spiral Z-stent covered with the woven Dacron graft. 3 D-CT was useful for the preoperative management and the surgical treatment of thoracic aortic dissection.

Down-regulation of IL-12 p40 gene in Plasmodium berghei-infected mice

We analyzed the mechanism that causes suppression of IL-12 p40 gene induction during Plasmodium berghei infection. Although IL-12 together with IFN-gamma plays an important role in protection against pathogenic infection, the IL-12 p70 protein production of infected macrophages is lower than that by the uninfected macrophages. We showed in the present study that the induction of IL-12 p40 gene but not IL-12 p35 gene in macrophages of P. berghei-infected mice was profoundly inhibited. The inhibition was induced by interaction with macrophages that had contacted with P. berghei-infected erythrocytes and was mediated by a soluble factor, IL-10. There was comparable activation of NF-kappaB in uninfected and infected cells. The induction of IFN-regulatory factor-1 gene was comparable in transcription level in uninfected and infected cells, while the unidentified complex formation of IFN-regulatory factor-1 was observed in infected cells. Therefore, the inhibition of the IL-12 p40 gene induction appeared to be regulated at transcriptional regulation level of the gene.

Gallic acid induces vascular smooth muscle cell death via hydroxyl radical production

In the present study, we investigated whether gallic acid (GA) can induce death in cultured vascular smooth muscle cells (VSMCs), and whether production of the hydroxyl radical (.OH) is involved in the process of GA action. GA killed cultured VSMCs from rat aorta, in a dosc- and time-dependent manner. Cytoplasmic shrinkage and nuclear condensation were observed light microscopically in GA-treated VSMCs, which appeared apoptotic. However, the ultrastructure of the VSMC was not typical of apoptosis: nuclear condensation was not glossy, and the plasma membrane and subccellular organelles were disrupted. Although the VSMC were positive for in situ nick end-labeling (TUNEL). they did not show a DNA ladder pattern on gel electrophoresis and were negative for T aq polymerase-based in situ ligation, which is more specific for apoptosis than TUNEL. Moreover. GA-induced cell death was not prevented by Boc-Asp-fmk (a pan-caspase inhibitor). Production of OH was detected in GA-treated VSMCs using high-performance liquid chromatography with salicylic acid as a trapping agent. Lipid peroxidation was also observed. The production of .OH was inhibited by catalase (CAT) and deferoxamine (DFX), and these treatments completely rescued VSMCs from cell death. In a cell-free system, GA produced .OH in the presence of Fe2+-EDTA, which was quenched by CAT and DFX, suggesting involvement of the Haber-Weiss reaction. Oxidative stress by reactive oxygen species, .OH in particular, is one of the mechanisms of GA-induced death of VSMCs, the mode of which was different from typical apoptosis.

Characterization of ultrastructure and its relation with DNA fragmentation in Fas-induced apoptosis of cultured cardiac myocytes

The purposes of the present study were to define precisely the ultrastructural features of apoptosis in cultured cardiomyocytes and to determine whether DNA fragmentation is essential for the apoptotic morphology. When cultured neonatal murine cardiomyocytes were incubated with an agonistic anti-Fas antibody in the presence of a non-toxic amount of actinomycin D or cycloheximide, approximately 70% of them had lost their viability after 24 h. The dead cardiomyocytes showed the typical ultrastructural changes of apoptosis on transmission and scanning electron microscopy, as well as by positive in situ nick end-labelling (TUNEL), positive Taq polymerase-based in situ ligation, a DNA ladder pattern on gel electrophoresis, and an increase in the active fragment of caspase-3. According to TUNEL at the electron microscopic level, apoptotic nuclear change, cytoplasmic shrinkage, and DNA fragmentation always occurred simultaneously in apoptotic cardiomyocytes. Other ultrastructural features of apoptosis were the appearance of abundant lipid-like structures in the cytoplasm of cardiomyocytes at the early phase, and a high incidence of plasma membrane rupture and formation of apoptotic bodies at the later phase. When zinc, an inhibitor of Ca2+/Mg2+-dependent endonuclease, was added to the present model, activation of caspase-3 and an apoptotic ultrastructure were still observed in spite of the lack of DNA fragmentation, indicating that this type of myocyte death is also apoptosis. In conclusion, the typical apoptotic ultrastructure and DNA fragmentation occur simultaneously in association with caspase-3 activation in Fas-stimulated cultured cardiomyocytes. Apoptotic morphology can, however, be observed even without DNA fragmentation.

Relationship between thallium-201 myocardial SPECT and findings of endomyocardial biopsy specimens in dilated cardiomyopathy

The purpose of this study was to clarify which myocardial histological findings associated with dilated cardiomyopathy (DCM) are reflected in quantitative 201Tl myocardial SPECT. We obtained studied SPECT images from 21 patients with DCM 10 minutes and 2 hours after they received an injection of 111 MBq 201Tl at rest. We calculated the percent coefficient of variation of myocardial 201Tl counts [%CV(TI)], the washout rate (WR), standard deviation of WR [SD(WR)], extent score (ES) and severity score (SS). We used image analysis to measure % fibrosis, % myocytes, the ratio of fibrous tissue to myocyte tissue (F/My), myocyte size and standard deviation of myocyte size [SD(My)] in left ventricular endomyocardial biopsy specimens. The %CV(Tl) was correlated with % fibrosis and F/My. The ES and SS also correlated with F/My. The correlation between SD(WR) and SD(My) was significant. The present findings suggest that %CV(Tl), ES and SS of rest 201Tl SPECT reflect myocardial fibrosis and that the standard deviation of washout reflects the distribution of myocyte size.

Mode and role of cell death during progression of atherosclerotic lesions in hypercholesterolemic rabbits

Two cell types, macrophages and smooth muscle cells (SMCs), play important roles in the development of atherosclerotic lesions. Both contribute to the formation of the lesions not only by their presence but also by taking in or releasing extracellular substrates during life and at death. The present study aimed to elucidate their turnover, focusing on the detailed description of the modes of death in each cell type, and the roles of their death in the progression from early into advanced atherosclerotic lesions. Ascending aortas were obtained from New Zealand white male rabbits fed a diet with 1% cholesterol for 3 months (3-M group, n= 6) and 6 months (6-M group, n = 6). They were histologically examined, and the cell death was checked by in situ nick end-labeling (TUNEL), using a Taq polymerase-based in situ ligation assay with/without combination of immunohistochemistry, electron microscopy (EM), and TUNEL at the EM level. Intimal hyperplasia and luminal stenosis advanced with increased dietary interval, and the aortic intima of the 3-M group consisted of histological types I-III atherosclerotic lesions, whereas that of the 6-M group included types III-V. Along with the progression, the cellular population decreased, but the area of fibrosis increased. The percentage area of macrophages declined (from 60% +/- 5% to 23% +/- 2%), but that of SMCs increased (from 5% +/- 1% to 10% +/- 2%). The positive cells for in situ ligation were less frequent in the 6-M group (0.05% +/- 0.01%) than in the 3-M group (0.2% +/- 0.04%), which was due to a decrease in SMCs positive for in situ ligation. The frequency of TUNEL-positive cells was higher than that of in situ ligation-positive cells in both groups, suggesting that cell death involved not only apoptosis but also oncosis. This was confirmed using EM: cell death occurred via both apoptosis and oncosis. EM-TUNEL positively labeled not only apoptotic but also some oncotic nuclei. Death of macrophages and SMCs involves both apoptosis and oncosis in the aortic intima of hypercholesterolemic rabbits. Decline in the dying rate of SMCs might be associated with the formation of SMC-rich and collagen-rich lesions in the late advanced stage of atherosclerosis, although such a cause-effect relationship is to be further confirmed.

Apoptosis and overexpression of bax protein and bax mRNA in smooth muscle cells within intimal hyperplasia of human radial arteries : analysis with arteriovenous fistulas used for hemodialysis

There is a type of arteriosclerosis with remodeling of middle-size arteries in which intimal hyperplasia of smooth muscle cells (SMCs) plays the main role, and there are few macrophages, T lymphocytes, and foam cells. It is unknown whether apoptosis and the expression of Bax, an inducer of apoptosis, are increased according to the progression of this type of human arteriosclerosis, which is different from so-called atherosclerosis. Bax heterodimerizes with Bcl-2, an inhibitor of apoptosis, and the ratio of Bax to Bcl-2 determines cellular apoptosis or survival. Thus, we investigated apoptosis and the expressions of Bax, bax mRNA, and Bcl-2 in human arteriovenous (AV) fistulas used for hemodialysis, a representative of arteriosclerosis of the aforementioned type. The material was 20 radial arteries obtained from 20 patients with chronic renal failure undergoing AV shunt surgery. SMCs, macrophages, and T lymphocytes were immunohistochemically identified at the light microscopic (LM) level. Apoptosis was detected by in situ terminal deoxynucleotidyl transferase (TdT)-mediated digoxigenin-dUTP nick end labeling (TUNEL) at both the LM and electron microscopic (EM) level. Cell proliferating activity was estimated by proliferating cell nuclear antigen (PCNA). Bax and Bcl-2 were detected by immunohistochemistry and Western blot analysis. Expression of bax mRNA was detected by in situ hybridization. LM TUNEL-positive cells in both the intima and media were significantly increased according to the percent stenosis of the vessels. EM analysis revealed that ultrastructures of apoptotic SMCs were seen in both synthetic and contractile phenotypes. Their frequency of occurrence in the intima and media were greater in those vessels with >50% stenosis than in those with <50% stenosis (5.2+/-0.7% versus 1.0+/-0.3% in the intima and 2. 1+/-0.5% versus 0.2+/-0.1% in the media). The proportion of apoptotic SMCs with ruptured plasma membranes was greater than that of apoptotic SMCs with intact membranes in the intima of the former (4.1+/-0.6% versus 1.1+/-0.1%). Only those SMCs with apoptotic ultrastructures had TUNEL-positive nuclei with moderate or marked accumulation of immunogold particles at the EM level. However, ultrastructures of oncosis (primary necrosis) were not observed. Immunohistochemical analyses showed significant positive correlations between percent stenosis of vessels and the percentage of either PCNA-positive intimal cells or Bax-positive areas in the intima and media. Bcl-2-positive cells were not observed in the intima but mainly in the outer media. The percentage of Bcl-2-positive medial cells was definitely decreased at an early stage after formation of the AV fistula but did not change according to the duration of hemodialysis or the progression of arteriosclerosis. Western blot analysis of Bax or Bcl-2 and in situ hybridization of bax mRNA confirmed the immunohistochemical data. Thus, regulation of cellularity in intimal hyperplasia of SMCs in human arteriosclerosis with remodeling is mediated by proliferation and apoptosis but not oncosis. The apoptosis is probably induced by an increase in the Bax to Bcl-2 ratio.

Significance of myocytes with positive DNA in situ nick end-labeling (TUNEL) in hearts with dilated cardiomyopathy: not apoptosis but DNA repair

BACKGROUND

The presence of apoptotic myocytes has been reported in human hearts with dilated cardiomyopathy (DCM) on the basis of a positive finding of DNA in situ nick end-labeling (TUNEL). However, ultrastructural evidence of myocyte apoptosis has not been obtained.

METHODS AND RESULTS

A total of 80 endomyocardial biopsies were obtained from right and left ventricles of 20 patients with DCM and 20 normal control subjects. TUNEL-positive myocytes were found by light microscope in 15% of DCM specimens (controls, 0%, P<0.05), and the percentage of TUNEL-positive myocytes per section in DCM was 1. 0+/-2.7% (mean+/-SD). According to TUNEL at the electron microscopic level (EM-TUNEL), immunogold particles, which label DNA breaks with 3'-OH terminals, were markedly accumulated in the bizarre-shaped nuclei, with widespread clumping of chromatin (so-called "hypertrophied nuclei") of the myocytes obtained from DCM. Their ultrastructure was neither apoptotic nor necrotic but rather that of living cells. Taq polymerase-based DNA in situ ligation assay, which detects double-stranded DNA fragments more specifically than TUNEL, did not detect a positive reaction in any case. In mirror sections, all of the TUNEL-positive myocytes in DCM simultaneously expressed proliferating cell nuclear antigen, which is required for both DNA replication and repair, but Ki-67, a replication-associated antigen, was completely negative in all cases, which appeared to rule out cell proliferation activity.

CONCLUSIONS

Most of the TUNEL-positive myocytes in hearts with DCM are not apoptotic but rather living cells with increasing activity of DNA repair.

Fifteen-year follow-up of a heterozygous Fabry's disease patient associated with pre-excitation syndrome

A 47-year-old woman with heterozygous Fabry's disease with pre-excitation syndrome has been followed up for 15 years. Diagnosis was confirmed by the typical electron microscopic feature of the endomyocardial specimen and a decreased plasma alpha-galactosidase activity. As the disease progressed, the interventricular septum thickened from 11 to 17 mm as measured by echocardiography, while the AH interval was prolonged from 80 to 140 msec. In Fabry's disease, the PR interval has been reported to be variable from short PR to AV block. Therefore, this case may be helpful to understand the time course in the AV conduction abnormalities with the progression of Fabry's disease.

Role of apoptosis in the disappearance of infiltrated and proliferated interstitial cells after myocardial infarction

Myocardial infarction (MI) progresses from the acute death of myocytes and the infiltration of inflammatory cells into granulation, followed by scars. During the healing process, the myocardial interstitial cell population in the infarcted tissues increases markedly and then decreases. We postulated that apoptosis is responsible for this process. Twenty-four male Japanese white rabbits underwent a 30-minute occlusion of the left coronary artery followed by reperfusion for 2 days, 2 weeks, or 4 weeks (n=8 each). The histological features consisted of dead cardiomyocytes and marked leukocyte infiltration at 2 days after MI and granulation consisting of numerous alpha-smooth muscle actin-positive myofibroblasts, macrophage antigen-positive macrophages, and neovascularization at 2 weeks. At 4 weeks, the cellularity decreased markedly, and scars were evident. Interstitial cells with positive nick end labeling were significantly more frequent at the light microscopic level in the 2-day MI samples (5.3+/-3.6% in the center and 6.9+/-3.3% in the periphery of the infarct region) than in the 2-week (2.5+/-1.0%) and 4-week (0.5+/-0.5%) samples. DNA electrophoresis showed a clear ladder in tissues from the ischemic areas at 2 days after MI but not at 2 and 4 weeks after MI. Ultrastructurally, typical apoptotic figures, including apoptotic bodies and condensed nuclei without ruptured plasma membranes, were detected in leukocytes from all hearts with 2-day MI and in myofibroblasts, endothelial cells, and macrophages from all hearts with 2-week MI. In the electron microscopic in situ nick end labeling, immunogold particles intensely labeled the condensed chromatin of the typical apoptotic nuclei. These particles were also accumulated on nuclei of the interstitial cells showing homogeneous density but not definite condensation as typical apoptotic nuclei, suggesting an early stage of apoptosis. Thus, apoptosis plays an important role in the disappearance of both the infiltrated leukocytes and the proliferated interstitial cells after MI. This finding may have therapeutic implications for postinfarct ventricular remodeling through apoptosis handling during the healing stage of MI.

[Postoperative infections related to pacing wires, pulmonary arterial catheters, and drainage tubes temporarily inserted during open-heart surgery]

Bacterial examinations of temporary pacing wires (P-wires), pulmonary arterial (P-A) catheters, and drainage tubes temporarily inserted during open-heart surgery were performed in 213 patients. Bacteria were detected in 19 (2.8%) of 672 specimens gathered from the subject patients, with coagulase-negative Staphylococcus (CNS) being most frequently observed. P-wires accounted for 17 out of 19 of the culture-positive specimens, and 7 of the P-wires remained in place for more than two weeks. The frequency of infection with the P-wires was significantly higher than with the P-A catheters or drainage tubes. The period of time that the P-wire was left in place significantly longer than for P-A catheter or drainage tube. There was, however, no statistically significant difference between the culture-positive and negative groups in respect to age, detention periods, operation times, CPB times, or length of ICU stay. As a result of these findings, we have concluded that P-wires should be removed as soon as possible following surgery, and in any case, a meticulous care should be taken to prevent transcutaneous infection.

Investigation of laser-induced fluorescence of several natural leaves for application to lidar vegetation monitoring

The laser-induced fluorescence spectra of living leaves of seven different trees were investigated by using a 355-nm pulsed Nd:YAG laser. The shapes of the spectra (360-800 nm) varied depending on the season and growing conditions. Generally, red fluorescence (>650 nm) was larger during summer to autumn, which offers information on the activity of photosynthesis, and blue-green fluorescence (<650 nm) was relatively large in early summer and late autumn to winter, which offers information on the progress of growth and senescence. The spectral shapes also varied depending on the organic constituents inside the leaves. Separation of the spectra into their components was tried to identify the leaves' constituents. These basic data are indispensable for developing a vegetation-monitoring fluorescence lidar.

[Intraventricular arachnoid cyst--on the origin of intraventricular arachnoid cysts]

Arachnoid cysts very rarely occur within the ventricular system, where no arachnoid tissue exists. We present three cases of intraventricular arachnoid cyst with special reference to its origin. The first patient was a 5-year-old boy who complained of headaches and enlargement of his head. A CT scan revealed obstructive hydrocephalus and a large cystic lesion in the right lateral ventricle. The symptoms resolved after fenestration of the cyst and cystoperitoneal shunt. The second patient was a 49-year-old woman who complained of headache and numbness in her left upper extremity. A CT scan and MRI revealed a large cyst in the trigone of the right lateral ventricle. Fenestration of the cyst wall and cystoperitoneal shunt were performed relieving her complaints. The third patient was a 42-year-old man who complained of frequent seizures and dizziness. A CT scan and MRI demonstrated a moderate size cystic mass in the inferior horn of the right lateral ventricle. The symptoms were improved by partial resection of the cyst wall. Immunohistochemical studies and light microscopy confirmed that the cyst walls were composed of arachnoid membrane, implying that the cysts were arachnoid cysts. CT and MRI in these three cases showed widening of the choroidal fissure bordering the cyst wall, occasionally involving a part of the protruding cyst wall. On enhanced CT and MRI, the choroid plexus in the trigone of ipsilateral lateral ventricle was displaced anterolaterally, implying that the cysts had grown from outside the choroid plexus. Postoperative MRI demonstrated the shrunken cyst wall attached to the choroidal fissure. The surgical findings in case 3 also showed that the cyst wall was attached firmly to the choroid plexus. These findings appeared to indicate that the intraventricular arachnoid cyst originated from the arachnoid layer drawn into the choroidal fissure with choroidal vascular mesenchyme.

A case of Fabry's disease with granulomatous interstitial nephritis

A 15-year-old boy with proteinuria and hematuria is reviewed in this study. He was first found to have urinary abnormalities at the age of 13 years, and his renal function was exacerbated for a short duration. Renal biopsy was performed to make a histological diagnosis and to establish adequate therapy. Light microscopy showed marked tubulointerstitial inflammation with granulomatous changes, and electron microscopy revealed that numerous osmiophilic inclusions were present in podocytes, mesangial cells, and endothelial cells of the glomeruli and in epithelial cells of the tubules. The alpha-galactosidase activity of lymphocytes from the patient was measured, and the results of this assay indicated that the patient's lymphocytes had a low level of alpha-galactosidase activity. Therefore, the patient was diagnosed as having Fabry's disease with renal dysfunction. This study demonstrated that the onset age of renal insufficiency in Fabry's disease may be earlier than that described previously, and that when granulomatous interstitial nephritis is developed, renal function may deteriorate progressively.

Immunochemical crossreactivity between globulins from buckwheat and indigo seeds

Immunochemical relationships between salt-soluble proteins (albumins plus globulins) from buckwheat and indigo seeds were shown by immunoblot and immunodiffusion analyses using rabbit antisera raised against buckwheat globulins. These antigenic crossreactivities were roughly consistent with their polypeptide components judged by two-dimensional electrophoresis and SDS-PAGE analyses.

[Rupture of dissecting aortic aneurysm associated with the right-sided aortic arch and anomalous course of the left brachiocephalic vein--a case report]

A case of ruptured dissecting aortic aneurysm (DeBakey IIIb) associated with the right sided aortic arch and anomalous course of the left branchiocephalic vein was reported. A sixty-nine-year-old female suddenly had the severe back pain and soon fell into shock. The diagnosis of a ruptured dissecting aortic aneurysm associated with the right sided aortic was obtained on CT scanning. CT films also showed the left brachiocephalic vein behind the ascending aorta. Emergency operation was performed through median sternotomy and left thoracotomy. The descending aorta, forming an aneurysm with the aberrant subclavian artery, prominently protruded far to the left, and was located behind the trachea and the esophagus. Extra-anatomical bypass grafting was performed between the ascending aorta and the distal descending aorta. The patient eventually died of multiple organ failure on the 11th day after operation. These findings were confirmed by autopsy. A rare vascular anomaly with aortic dissection was reported, and a surgical approach to that lesion was discussed.

Complement activation by cross-linked B cell-membrane IgM

The B cell membrane IgM (mIgM) occurs in a monomeric form incapable of activating C. However, when cross-linked by a polyvalent ligand, mIgM may activate C by assuming a polymeric structure like secreted IgM. This possibility was tested with CR2- lymphoma cells, which did not activate C spontaneously. When CR2-deficient mIgM(lambda)+ Ramos cells were treated with F(ab')2 goat anti-lambda, then exposed to human serum, a marked C3 deposition took place, as examined by the flow cytometry. Similarly, C3 deposition on mIgM(kappa)+, mIgD(kappa)+ P32 cells was induced by F(ab')2 of either anti-kappa or anti-mu. Anti-delta was without effect, but the C3 deposition resulting from anti-kappa was markedly enhanced after mIgD was modulated by anti-delta. The mIgM-cross-linked cells bound C1q, and C3 deposition on these cells was abrogated by depletion of C1q, but not Factor B nor D, from serum. The C1-binding step of the mIgM-mediated C activation was inhibited by monomeric Fab' of polyclonal anti-mu containing a blocking Ab to the hemolytic activity of human IgM Forssman Ab. A large proportion of C3 deposits on mIgM-cross-linked cells was found to be associated with mIgM in the form of C3dg or C3d. These results demonstrate that cross-linked mIgM indeed triggers the classical pathway of C.

Complement activation by cross-linked B cell-membrane IgM

The B cell membrane IgM (mIgM) occurs in a monomeric form incapable of activating C. However, when cross-linked by a polyvalent ligand, mIgM may activate C by assuming a polymeric structure like secreted IgM. This possibility was tested with CR2- lymphoma cells, which did not activate C spontaneously. When CR2-deficient mIgM(lambda)+ Ramos cells were treated with F(ab')2 goat anti-lambda, then exposed to human serum, a marked C3 deposition took place, as examined by the flow cytometry. Similarly, C3 deposition on mIgM(kappa)+, mIgD(kappa)+ P32 cells was induced by F(ab')2 of either anti-kappa or anti-mu. Anti-delta was without effect, but the C3 deposition resulting from anti-kappa was markedly enhanced after mIgD was modulated by anti-delta. The mIgM-cross-linked cells bound C1q, and C3 deposition on these cells was abrogated by depletion of C1q, but not Factor B nor D, from serum. The C1-binding step of the mIgM-mediated C activation was inhibited by monomeric Fab' of polyclonal anti-mu containing a blocking Ab to the hemolytic activity of human IgM Forssman Ab. A large proportion of C3 deposits on mIgM-cross-linked cells was found to be associated with mIgM in the form of C3dg or C3d. These results demonstrate that cross-linked mIgM indeed triggers the classical pathway of C.

[Perforation of the right ventricular wall and extraction into the left thoracic cavity by a permanent endocardial pacemaker lead: a case report]

A 80-year-old woman with right ventricular wall perforation and extraction into the left thoracic cavity by a permanent endocardial pacemaker (PM) lead was presented. The patient underwent an insertion of a permanent endocardial lead into the apex of the right ventricle for the treatment of sick sinus syndrome. The right ventricular perforation of the PM lead was incidentally diagnosed by recognizing it into the left thoracic cavity three months after the operation. Another PM lead could be inserted without removal of the former one.

A method for simultaneous detection of fluorescent G-bands and in situ hybridization signals

Improved techniques for detecting in situ hybridization signals on fluorescent G-bands are described. Prior to hybridization of biotinylated DNA probes, chromosomes with replication G-bands were treated with formaldehyde and denatured with an alkaline solution. These steps preserve chromosome morphology well, and enable us to simultaneously demonstrate fluorescein hybridization signals and G-banded chromosomes stained with propidium iodide. This method is useful for precise chromosomal localization of DNA markers.

Cytidylate cyclase activity is stimulated via activation of a guanine nucleotide-binding protein

Cytidylate cyclase is a membrane-bound enzyme which catalyzes the biosynthesis of cytidine 3',5'-cyclic monophosphate (cCMP) from CTP. By using a sensitive and specific enzyme immunoassay method, we evaluated the participation of guanine nucleotide-binding protein (G-protein) in the regulation of cytidylate cyclase activity in rat brain and other tissues. AlF4-, an activator of G-proteins, effectively elevated the cyclase activity. The stimulation by GTP gamma S, a nonhydrolyzable GTP analogue, was also observed in time- and concentration-dependent manner during the preincubation and this effect was competitively inhibited by the addition of GDP beta S. However, islet-activating protein and cholera toxin which affected adenylate cyclase activity had no effect on cytidylate cyclase activity. These results indicate that cytidylate cyclase is associated with a certain G-protein and its activity is regulated by the mode different from that of adenylate cyclase.

[The prevalence and the clinical characteristics of silent myocardial ischemia detected by stress thallium scintigraphy]

The prevalence of silent myocardial ischemia was retrospectively assessed in a group of 100 consecutive patients with angiographically proved coronary artery disease, and diagnostic ECG, by symptom-limited exercise thallium-201 scintigraphy. Twenty-four patients had no evidence of ischemia despite adequate exercise level. So among 76 patients with exercise induced ischemia, only 33 patients (43%) stopped exercise due to anginal pain (symptomatic ischemia: Group 3). And 43 patients with asymptomatic ischemia composed of 23 patients (30%) with ECG change (Group 2B) and 20 patients (26%) without ECG change (Group 2A). Patients background including the history of old myocardial infarction and diabetes mellitus, were similar among Group 2A, 2B, and Group 3. And our major observation was that the extent and severity of quantified SPECT perfusion defects was nearly identical between 3 groups Thus in this study group, there was a rather high prevalence rate of silent ischemia (57%) by exercise thallium-201 criteria. Patients with silent ischemia, associated with positive and negative exercise ECG findings, and those with exercise angina had similar background and comparable amount of jeopardized myocardium.

Differential upregulation of PLP and MAG genes in C6 glioma cells by N2A neuroblastoma conditioned medium

The effect of factors released from N2A neuroblastoma cells on the expression of myelin protein genes in glioma C6 cells, i.e., proteolipid protein (PLP) and myelin-associated glycoprotein (MAG), was studied. Both cells lines were propagated in serum-free DMEM-F10 (1:1) medium. The addition of 50% N2A conditioned medium (N2ACM) stimulated the proliferation of C6 cells by approximately 4.5 fold as compared to control cells. The N2ACM-treated cells formed aggregates indicating increased cell-cell affinity. The exposure of C6 cells to N2ACM transiently stimulated the expression of both the MAG-specific and the PLP-specific messages up to eight and four fold over the control values, respectively. The maximal upregulation of the PLP gene occurred two days after N2ACM administration and preceded that of the MAG gene by two days. The effect of N2ACM was dose-dependent in the range of 12.5 to 50%. The secretion of N2A paracrine factors that stimulated the myelin gene expression was also time-dependent. The optimal conditioning time for the release of the PLP gene-stimulating activity was one day, while the maximal MAG gene-stimulating activity was found in the medium conditioned for 3 days. This cellular system may provide a convenient model for studies on trophic neuronal-glial interaction. Furthermore, the results indicate a difference in the regulatory mechanisms between the PLP and the MAG genes.

[Presence of human epidermal growth factor (hEGF), basic fibroblast growth factor (bFGF) in human aqueous]

Thirty-eight cataract eyes and 15 artificial aphakic or pseudophakic eyes were enrolled in this study to determine levels of human epidermal growth factor (hEGF) and basic fibroblast growth factor (bFGF) in human aqueous, using a radioimmunoassay. Neither hEGF nor bFGF were detected in either congenital cataract eyes or senile cataract eyes without any complication. In cases of senile cataract complicated with glaucoma and traumatic cataract, bFGF range from 0.4 to 0.8 ng/ml whereas hEGF was not detected. In cases of senile cataract with myocardial or brain infarction and anterior subcapsular cataract, bFGF was detected ranging from 0.4 to 1.0 ng/ml and in some of the cases hEGF was detected at a level of 1.0 ng/ml. hEGF was detected at 1.0 ng/ml in some cases of secondary cataract after uveitis, cataract complicated with retinal detachment, cataract after scleral buckling or vitrectomy, and aphakic or pseudophakic eyes after extracapsular cataract extraction or phacoemulsification. These results showed that hEGF and bFGF exist at a level of about 1 ng/ml in human aqueous in some pathological states and it seems possible that proliferation of lens epithelial cells is promoted by the growth factors, with the result that after cataract, anterior capsular opacities and shrinkage become severe.

Retinoic acid-regulated expression of proteolipid protein and myelin-associated glycoprotein genes in C6 glioma cells

The effect of retinoic acid (RA) on the expression of myelin-specific genes, i.e., proteolipid protein (PLP) and myelin-associated glycoprotein (MAG) in rat glioma C6 cells, was analyzed by Northern blot hybridization. RA-treatment increased the steady-state level of the PLP-specific messages within one day after RA administration and the upregulation reached a maximum on the third day. Concomitantly, the expression of MAG-specific messages in the RA-treated C6 cells dropped below the detectability limit. The expression of the PLP gene was directly related to the RA concentration increasing to approximately 44-fold over the control (untreated cells) level at 10(-6) M RA. The stimulatory effect was vitiated by cycloheximide indicating the involvement of intermediate genes in the PLP gene activation. The total cellular RNA content and the level of cyclophilin mRNA was not changed by the RA-treatment. The present data indicate that RA can be a potent modulator of the myelin-specific gene expression. Furthermore, the reciprocal response of PLP versus MAG genes to RA demonstrates that these two genes utilize different regulatory mechanisms.

Reduction of cerebral blood flow in chronic schizophrenia: relation to age

The effect of age on resting-state cerebral blood flow (CBF) was studied in 40 medicated patients with chronic schizophrenia aged 20 to 57 and 32 age- and sex-matched normal controls, using the regional CBF with the xenon-133 inhalation technique. Global CBF (average of 16 cerebral regions) and the left prefrontal flow ratio (left prefrontal/global CBF) were significantly lower in schizophrenics aged 20-29 than in age-matched controls. Both global CBF and the left prefrontal flow ratio correlated with age in controls, but neither of such correlations was found in schizophrenics. Therefore, the CBF deficits in chronic schizophrenia appear to be unaffected by the aging process.

Cyclic AMP-induced upregulation of proteolipid protein and myelin associated glycoprotein gene expression in C6 cells

A model culture system of C6 rat glioma cells was used to test the involvement of cAMP in the regulation of the myelin PLP and MAG genes. The treatment of cells with isoproterenol (10(-5) to 10(-8) M) upregulated the expression of the PLP and MAG genes in a concentration-dependent manner. The mRNA for PLP reached a maximum (sevenfold higher than in control cells) after about 12-24 hr, then declined to approximately fourfold over the control level. The response of MAG gene was delayed by at least 36 hr, and the level of MAG mRNA reached a maximum of approximately 48-fold over the control level on the fourth day in culture. The co-administration of propranolol blocked the effect of isoproterenol, whereas 10(-5) M forskolin simulated the effect of isoproterenol, indicating a role of cAMP in the signal transduction cascades leading to upregulation of the myelin genes. However, the dissimilarity in the timing and the extent of upregulation of the PLP and MAG genes by cAMP-stimulating agents indicate the existence of different intracellular mechanisms for the activation of these two genes. Cycloheximide blocked the stimulatory effect of isoproterenol on both the PLP and MAG genes, indicating that the effect of cAMP on the myelin genes is mediated by protein product(s) of other cAMP-response gene(s).

Down regulation of myelin-specific mRNAs in the mechanism of hypomyelination in the undernourished developing brain

The expression of myelin-specific protein genes, i.e. myelin proteolipid (PLP), basic (BP), and myelin associated glycoproteins (MAG) was studied in normal and severely undernourished 20-day-old rats. The undernutrition paradigm resulted in reductions of approximately 50, 25 and 65% in body weight, brain weight and brain myelin yield, respectively. The amount of total brain RNA was not significantly altered, although the amount of cyclophilin (CYC) mRNA was increased. In contrast, the steady-state levels of myelin specific mRNAs were significantly decreased by approximately 40, 20 and 40% for PLP, BP and MAG, respectively. In addition, polyadenylation of the PLP transcript was altered, producing an abnormal ratio of the 1.6 kb to the 3.2 kb PLP mRNAs. The results indicate that down-regulation of myelin-specific gene expression is involved in the mechanisms of hypomyelination in hunger disease, although the individual genes are differently altered. Furthermore, undernutrition may have additional effects on the posttranscriptional processing of the transcripts as indicated by the abnormal size distribution of PLP messages.

Effect of culture conditions on PLP and MAG gene expression in rat glioma C6 cells

The effects of culture conditions on the expression of myelin-specific genes, i.e. proteolipid protein (PLP) and myelin-associated glycoprotein (MAG) in rat glioma C6 cells was studied. Early passage (40-46) cells had higher steady-state level of PLP- and MAG-specific mRNA than late (100) passage cells when grown in defined (serum-free) medium. The PLP gene expression was increased whereas the MAG gene expression was reduced in the presence of 10% fetal calf serum in either passage. The level of both PLP- and MAG-specific messages was also directly related to the cell density indicating cell contact-induced stimulation of the gene expression. Furthermore, the cells apparently secrete factors into the medium, which upregulate the gene expression in autocrine fashion. The results also indicate a dissimilarity of regulatory mechanisms involved in the expression of the PLP and MAG genes.

Differential regulation of myelin gene expression in SV40 T antigen-transfected rat glioma C6 cells

Rat glioma C6 cells were stably transfected with a pSV3-neo plasmid containing SV40 T antigen gene, and geniticin-resistant transfectants (designated C6T cells) were cloned. The C6T cells grew as well-defined foci of cells showing squamous or irregular morphology. The doubling time for transfected cells was reduced by approximately 40% as compared to control C6 cells. The transfection with T-antigen also affected the expression of genes coding for structural myelin proteins and for myelin-associated enzymes. The steady-state level of proteolipid protein (PLP)-specific mRNA in C6T cells was 44% lower than in parental C6 cells. On the other hand, the transfection upregulated the expression of myelin-associated glycoprotein (MAG) by 153%. The activity of 2':3' cyclic AMP phosphodiesterase (CNP) was increased by approximately 80% in the C6T cells as compared to untransfected, control cells. The activity of calcium-activated neutral proteinase (CANP) was also significantly elevated in the transfectants by approximately 50% and 220% for millimolar and micromolar form respectively. The results indicate that T antigen affects the expression of myelin genes, although, individual genes appear to be differently regulated implying the existence of several independent regulatory mechanisms.

In vitro IgG rheumatoid factor production by CD5-negative murine B cells in response to immune complexes of lipopolysaccharide

We studied the in vitro production of rheumatoid factor (RF) by spleen cells of normal adult mice. IgG RF cross-reactive with rabbit IgG was produced in response to immune complexes of TNP-lipopolysaccharide (LPS) with murine IgG anti-TNP antibody in an Fc-specific manner, but not to a mixture of IgG and LPS. Antibody-uncomplexed LPS induced little IgG RF production, but suppressed the subsequent IgG RF response to antibody-complexed LPS, whereas IgM RF was induced by either LPS or antibody-complexed LPS. The IgG RF production followed as rapid a time course as IgM RF production; the rate of IgG RF production reached its maximum soon after a lag period of 1 day and declined after 5 days. Treatment of splenic B cells from BALB/c mice with anti-Ly-1.2 antibody and rabbit complement resulted in a selective reduction of IgM RF production by 90%, with little effect of IgG RF production. These results suggest that IgG RF is derived primarily from CD5- memory B cells which have been developed in normal mice by an unknown mechanism. Unlike the CD5+ precursor cells for IgM RF, these memory cells are unresponsive to polyclonal stimulation by LPS but are activated by simultaneous stimulation by aggregated Fc epitopes and the mitogenic stimulus from LPS.

Lymphokine-independent, leukemia cell-mediated induction of tumor necrosis factor in human monocytes

Unactivated human blood monocytes and monocytic THP-1 cells were found to respond to some leukemia cells by tumor necrosis factor (TNF) production. The TNF production by THP-1 cells in response to K562 cells was preceded by a rapid rise in [Ca2+]i, initiated within 1 h and terminated within 4 h as a refractory state took over. Neither the amount nor the duration of TNF production was enhanced by gamma-interferon. The P32/ISH cells did not induce a significant [Ca2+]i change of TNF production, while MOLT-4 cells failed to induce TNF despite their capacity to mobilize Ca2+ in THP-1 cells. The failure of P32/ISH or MOLT-4 to induce TNF was attributed primarily to a lack of stimulatory membrane molecules rather than to suppression by an inhibitory component, since liposomes carrying membrane components of K562 and MOLT-4 or P32/ISH in varying proportions elicited TNF production that precisely reflected the K562 proportion. The ability of K562 to induce TNF was selectively impaired by trypsin, whereas the ability to mobilize [Ca2+]i was more sensitive to glutaraldehyde, although once the latter activity was extinguished, the K562 cell could no longer induce TNF. These results suggest that some leukemia cells are equipped with two or more signaling membrane moieties which together stimulate monocytes for transient tumoricidal expression in the preimmune stage.

IgG isotype and isotype specificity of murine monoclonal IgG rheumatoid factors

Immune complexes of lipopolysaccharide (LPS) with homologous IgG antibody induces rheumatoid factor (RF) predominantly of the IgG class in normal mice, while LPS alone induces mostly IgM RF directed to homologous IgG1. In this study, IgG monoclonal RFs (mRF) were prepared from hybridomas derived from spleen cells of BALB/c mice which were immunized with complexes of TNP-LPS with anti-TNP mouse IgG and their specificity to mouse IgG subclasses was assessed by analysing dissociation kinetics of the ligands due to RF-specific and non-specific interactions. Of the 19 IgG mRFs (11 IgG1, five IgG2a, one IgG2b and two IgG3 types) tested, 14 were directed to either IgG3 or IgG2b or both, while only one exhibited a significant binding capacity to IgG1. Other mRFs, although reactive to rabbit IgG, exhibited little homophilic activity. None of these mRFs reacted strongly with their own isotypes. The results suggest that the IgG RF producing cells are not direct progenies of the IgG1-directed IgM RF-producing cells but may have developed via a rigorous selection process to eliminate clones that produce self-reactive RF.

Epidermoid of the quadrigeminal cistern--case report

The authors report a case of an epidermoid in the quadrigeminal cistern in a 40-year-old female who presented with headache and nausea. According to the literature, epidermoids are rarely found in the quadrigeminal cistern. Additional unusual features in this case were the absence of a capsule and T1-weighted magnetic resonance images suggestive of both solid (less intense) and fluid (more intense) components.

[Recurrent cerebral aneurysm suggestive of misplaced clipping. Case report]

A case of recurrent cerebral aneurysm after complete neck clipping is described. A 47-year-old male who presented with headache and nausea underwent neck clipping of a berry aneurysm of the left middle cerebral artery. Ten days later, angiographic findings suggested the presence of a second, large aneurysm adjacent to the first, which suggested misplaced clipping. Reoperation confirmed that a new aneurysm had formed next to the original aneurysm. A possible explanation of the recurrence is as follows. The M1 flowed into the M2 at a right angle. The aneurysmal neck was situated on the distal end of the M1 and the dome protruded antero-inferiorly at an angle of nearly 90 degrees to the long axis of the M1 opposite the origin of the M2. The parent artery bulged slightly, and its wall was thin and reddish, just distal to the aneurysmal neck. Proximal to the neck there was another small bulge, but the wall here was normal. These bulges were coated with Oxycel and Biobond at the time of aneurysmal neck clipping. After clipping, blood flow into the dome was interrupted, and the consequent hemodynamic stress caused the bulges to expand dramatically and form a new aneurysm. The authors conclude that there is a likelihood of early recurrence after neck clipping if the parent artery exhibits such morphological features as observed in this case.

Monoclonal antibodies recognizing different epitopes of the 27-kDa gap junction protein from rat liver

Monoclonal antibodies (2-3E2, 6-3G11, and 7-3H6) against gap junction plaques purified from rat liver were prepared and characterized. Immunoblot analysis of liver gap junctions revealed that all three antibodies reacted with the 27-kDa protein, but not with the 22-kDa one. The 2-3E2 and 6-3G11 antibodies both reacted with the 27-kDa protein in gap junctions purified from livers of the rat, mouse, rabbit, and guinea pig; the 7-3H6 antibody, however, failed to react with the 27-kDa protein from guinea pig liver. The 7-3H6 antibody reacted strongly with the 24- to 26-kDa degradation products of the 27-kDa protein. Indirect immunofluorescence showed that the 6-3G11 and 7-3H6 antibodies both gave the same specific fluorescence labeling on rat liver cryosections, suggesting that these two antibodies recognized the cytoplasmic sites of the 27-kDa protein. Immunoblot analysis of protease-digested fragments from the 27-kDa protein revealed that the 7-3H6 antibody reacted with the 24- and 17-kDa fragments (including portions of the carboxyl-terminal domain of the 27-kDa protein) produced with endoproteinases Arg-C and Lys-C, respectively. Immunoblot analysis of CNBr fragments of the 27-kDa protein revealed that all three antibodies reacted with the 10-kDa fragment, which is thought to be the carboxyl-terminal domain of the 27-kDa protein. These results demonstrate that three monoclonal antibodies recognize different epitopes of the cytoplasmic sites (probably the carboxyl-terminal domain) of the 27-kDa liver gap junction protein.