Colocalization of GP125/CD98 with tropomyosin isoforms at the cell-cell adhesion boundary

Two monoclonal antibodies designated as 1F6 and 4B10 were obtained on screening for reactivities to CD98-associated molecules by sandwich-type enzyme-linked immunosorbent assaying using hybridoma culture supernatants as the solid phase, cell lysates as an antigen source, and a mixture of biotinylated antibodies to CD98HC as a detector. Flow cytometric analysis with microspheres in combination with 1F6, 4B10, and anti-CD98HC also indicated the association of antibody-defined antigen(s) with CD98. 1F6 and 4B10, stained fibrillate components in fixed and permeated cells but were not reactive with unfixed live cells, suggesting that epitopes reside in the cytoskeleton-associated structure in the intracellular region. Two-color immunostaining followed by confocal microscopy revealed the colocalization of the antigen with CD98 at the cell-cell adhesion boundary of HeLa cells. 1F6 detected proteins with relative molecular masses of 33,000 to 43,000 on immunoblotting analysis involving cell lysates of human and rat cell lines. Analysis with a purified tropomyosin specimen from rabbit skeletal muscle demonstrated that 1F6 and 4B10 recognize tropomyosin. Two-dimensional gel electrophoresis followed by immunoblotting analysis revealed that 1F6 recognizes various tropomyosin isoforms. These results indicated that CD98 physically associates directly or indirectly with tropomyosin, and that this association is closely related to the cell-cell interaction.

[Does reperfusion therapy reduce complications in acute inferior myocardial infarction?]

Both right ventricular infarction and complete atrioventricular block were frequently seen in patients with acute inferior myocardial infarction before the introduction of reperfusion therapy (RT). However, the effect of reperfusion therapy on these 2 complications is not well known. To evaluate the effect of reperfusion therapy in them, we retrospectively studied the in-hospital outcome of 103 consecutive patients with acute inferior myocardial infarction within 72 hr after the onset, 23 with right ventricular infarction and 36 with complete atrioventricular block. Patients were divided into 2 groups: RT group (n = 63) in which Thrombolysis in Myocardial Infarction (TIMI) III flow was obtained by reperfusion therapy within 24 hr after the onset, and the non-RT group (n = 40) in which TIMI III flow was not obtained or did not receive reperfusion therapy. Patients with right ventricular infarction in the RT group had a larger proportion of proximal occlusion of the right coronary artery and the absence of preinfarction angina. There were no effects of perfusion on complete atrioventricular block. In 23 patients with right ventricular infarction and 36 patients with complete atrioventricular block, in-hospital stay, duration of using temporary pacing and Swan-Ganz catheter were shorter in the RT group than the non-RT group. Reperfusion therapy does not decrease the incidence of both complications. However, successful reperfusion therapy results in a rapid improvement in hemodynamic instability and atrioventricular conduction injury, and early hospital discharge. Preinfarction angina may be associated with a protective effect against the development of these 2 complications.

[A successful case of hybrid therapy for the left main trunk and triple coronary vessel lesions with acute myocardial infarction and cardiogenic shock]

A 86-year-patient who had acute myocardial infarction and critical cardiogenic shock was diagnosed to have the left main trunk (LMT) and triple vessel disease. Emergent coronary artery bypass grafting to the left anterior descending artery was performed using saphenous vein graft without cardiopulmonary bypass through median sternotomy. On the 41st postoperative day, catheter intervention was performed to the remaining lesions by stenting of LMT and percutaneous transluminal coronary angioplasty to the right coronary artery lesions. Tl scintigraphy showed remarkable reduction of myocardial ischemia. Hybrid therapy is the effective new strategy for critical cases which cannot be successfully and securely treated by medical or surgical approach alone.

Is preinfarction angina related to the presence or absence of coronary plaque rupture?

OBJECTIVE

To analyse the prodrome of acute myocardial infarction in relation to the plaque morphology underlying the infarct.

DESIGN

A retrospective investigation of the relation between rupture and erosion of coronary atheromatous plaques and the clinical characteristics of acute myocardial infarction. The coronary arteries of 100 patients who died from acute myocardial infarction were cut transversely at 3 mm intervals. Segments with a stenosis were examined microscopically at 5 micrometer intervals. The clinical features of the infarction were obtained from the medical records.

RESULTS

A deep intimal rupture was encountered in 81 plaques, whereas 19 had superficial erosions only. There were no differences in the location of infarction, the incidence of hypertension, diabetes mellitus, or hyperlipidaemia, diameter stenosis of the infarcted related artery, Killip class, Forrester's haemodynamic subset, or peak creatine kinase between plaque rupture and plaque erosion groups. The presence of plaque rupture was associated with significantly greater incidences of leucocytosis, current smoking, and sudden or unstable onset of acute coronary syndrome. In patients with unstable preinfarction angina, new onset rest angina rather than worsening angina tended to develop more often in the plaque rupture group than in the plaque erosion group (p = 0.08).

CONCLUSIONS

Plaque rupture causes the sudden onset of acute myocardial infarction or unstable preinfarction angina, which may be aggravated by smoking and inflammation.

Transpapillary biopsy in gallbladder disease

BACKGROUND

Endoscopic biopsy is routine in gastrointestinal disease; similarly, histopathologic diagnosis is desirable in gallbladder disease. In this study we examined the clinical usefulness and the problems associated with transpapillary gallbladder biopsy.

METHODS

Transpapillary gallbladder biopsy was attempted in 9 patients with gallbladder disease. After inserting a catheter sheath into the gallbladder using a guidewire via the transpapillary route without sphincterotomy, we inserted a biopsy forceps into the lumen of the sheath up to the gallbladder lumen and obtained specimens.

RESULTS

We could obtain sufficient specimens for histopathologic diagnosis in 8 of 9 cases (88.9%). Of the 8 successful cases, targeted specimens were obtained in 7 (87.5%). Diagnostic accuracy with respect to malignant versus benign disease was 100% (2 of 2) and 83.3% (5 of 6), respectively. There were no complications.

CONCLUSION

Transpapillary gallbladder biopsy is a clinically useful technique because it facilitates histopathologic diagnosis and therefore guides the choice of therapy.

Five phenolic glycosides from Alangium chinense

From the dried leaves of Alangium chinense, five novel phenolic glycosides, 6'-O-galloylsalicin (1); 4',6'-di-O-galloylsalicin (2); 4',6'-O-(S)-hexahydroxydiphenoylsalicin (3); 4', 6'-O-(R)-hexahydroxydiphenoylsalicin (4); and pyrocatechol 1-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranoside (5) were isolated. The structures of these new compounds were determined by spectroscopic methods.

An evaluation of three-dimensional ultrasonography for the measurement of gallbladder volume

OBJECTIVE

Various three-dimensional ultrasonography systems have been developed. We estimated the accuracy of a three-dimensional ultrasonography system for measuring gallbladder volume and compared the results to the sum-of-cylinders method.

METHODS

In an in vitro study, 10 balloons of various shapes, sized 5-68 mL were scanned by real-time ultrasonography. In an in vivo study, we evaluated the gallbladder emptying of 14 healthy male volunteers after ingestion of two raw egg yolks. In both studies, volume measurement was performed by the three-dimensional ultrasonography method and the sum-of-cylinders method.

RESULTS

With the three-dimensional ultrasonography method, the mean difference between the measured volume and the true volume and the limits of agreement were smaller than those of the sum-of-cylinders method. Gallbladder volumes did not differ significantly with both ultrasound methods.

CONCLUSION

The three-dimensional ultrasonography method accurately determined gallbladder volumes.

A survey of filling methods, intracanal medications, and instrument breakage

The present survey was conducted to obtain answers to some basic questions regarding the use of intracanal medications, root canal filling methods, and the intracanal breakage of instruments. A letter was sent to 300 endodontists listed in the 1995-1996 membership roster of the American Association of Endodontists. Eighty-five replies were received. Calcium hydroxide as an intracanal medication was used by 91.7% of the responding endodontists. With regard to the root canal filling technique, 52.9% used the lateral condensation method. When intracanal breakage occurred, 95.3% of the respondents informed the patient. The results of this survey provide useful information for the education of undergraduate dental students.

Ipecac alkaloids from Cephaelis acuminata

From the dried roots of Cephaelis acuminata, five ipecac alkaloids, neocephaeline, 7'-O-demethylcephaeline, 10-O-demethylcephaeline, 2'-N-(1"-deoxy-1"-beta-D-fructopyranosyl)cephaeline and 2'-N-(1"-deoxy-1"-beta-D-fructopyranosyl)neocephaeline, were isolated, along with emetine, cephaeline, psychotrine, protoemetine, 9-demethylprotoemetinol and isocephaeline. Structures were determined by spectroscopic and chemical means.

Impairments of long-term potentiation in hippocampal slices of beta-amyloid-infused rats

In this study, we investigated the neuronal activity of hippocampal slices from the beta-amyloid protein-infused (300 pmol/day for 10-11 days) rats using the extracellular recording technique. Perfusion of nicotine (50 microM) reduced the amplitude of electrically evoked population spikes in the CA1 pyramidal cells of the vehicle control rats, but not in those of the beta-amyloid protein-infused rats, suggesting the impairment of nicotinic signaling in the beta-amyloid protein-infused rats. Long-term potentiation induced by tetanic stimulations in CA1 pyramidal cells, which was readily observed in the vehicle control rats, was also impaired in the beta-amyloid protein-infused rats. Nicotinic blockade by adding hexamethonium into the perfused solution inhibited long-term potentiation induction. Taken together, our previous and present results suggest that beta-amyloid protein infusion impairs the signal transduction mechanisms via nicotinic acetylcholine receptors. This dysfunction may be responsible, at least in part, for the impairment of long-term potentiation induction and may lead to learning deficits.

Changes in cortical width with bone turnover in the three different endosteal envelopes of the ilium in postmenopausal osteoporosis

Histological indicators of bone turnover were compared in the three endosteal envelopes (cancellous, endocortical, and intracortical) of iliac bone specimens obtained from 82 osteoporotic women, to assess the correlation between bone turnover and bone volume in different remodeling sites. Although there was a significant but weak correlation between the mineral apposition rate (MAR), a histological indicator of bone formation at the basic multicellular unit (BMU) level, and the three endosteal envelopes, the bone formation rate corrected for bone surface (BFR/BS) and mineralizing surface (MS/BS), indicators of the rate of bone formation reflecting activation frequency, in the cancellous and endocortical envelopes was more closely related to the rate in the intracortical envelope. The endocortical BFR/BS and MS/BS were higher than the rate in the cancellous envelope (1.6-2.1 times and 2.0-2.4 times, respectively), indicating a higher turnover rate in the endocortical envelope. According to stepwise regression analysis of the significant determinants contributing to bone mass, several histological determinants relating to bone turnover were identified: (1) trabecular thickness (Tb.Th) was a positive determinant, whereas age and cancellous bone volume referent BFR (BFR/BV) were negatively correlated determinants of the cancellous bone volume (BV/TV) (R2 = 0.50, p < 0.001); and (2) the endocortical wall thickness (W.Th) of the given side and the cortical width (Ct.Wi) of the opposite side were positive determinants, whereas the cancellous osteoid surface (OS/BS), cancellous MAR, and endocortical eroded surface (ES/BS) of the given side were the negatively correlated determinants of the Ct.Wi of the thicker cortex (R2 = 0.62, p < 0.001). In the thinner cortex, the endocortical W.Th of the given side and Ct.Wi of the opposite side were only used as the positive determinants of the Ct.Wi of the given side (R2 = 0.55, p < 0.001). In addition: (3) a significant but weak correlation was found using the intracortical BFR/BV as a positively correlated determinant of the cortical porosity (Ct.Po) in the thicker cortex (R2 = 0.17, p < 0.01). Although these histological determinants do not fully explain the mechanisms of bone loss, an increased rate of bone turnover contributes to bone loss not only in the cancellous and intracortical envelopes, but also in the endocortical envelope, indicating increased endocortical bone resorption in osteoporosis.

[Prognosis for patients with angina pectoris accompanied by chronic renal failure]

Chronic renal failure (CRF) is one of the risk factors of a worse outcome for patients with coronary artery disease. However, few studies have assessed the outcome in such patients. This study investigated the clinical characteristics, treatment modalities, and prognosis for patients with angina pectoris accompanied by CRF and evaluated the validity of current treatment strategy for these patients. A total of 593 patients (248 with stable angina and 345 with unstable angina) admitted to our institution were studied. Renal failure was defined as serum creatinine of > or = 2.0 mg/dl. Patients were divided into 2 groups, with renal failure (46 patients) and without renal failure (547 patients), and the former group was further divided into 2 groups with hemodialysis (26 patients) and without hemodialysis (20 patients). The mean follow-up period was 2.5 +/- 1.2 years and the follow-up rate was 99%. The prevalences of congestive heart failure (26% vs 3%, p < 0.001), hypertension (72% vs 45%, p < 0.005), and multivessel coronary artery disease (65% vs 33%, p < 0.001) were higher in patients with CRF. The left ventricular end-diastolic volume was greater in patients with CRF than in patients without CRF (114 +/- 36 vs 85 +/- 24 ml/m2, p < 0.001). The calcification score of both coronary arteries and abdominal aorta evaluated by electron-beam computed tomography was higher in patients with CRF (2,187 +/- 2,727 vs 631 +/- 841, p = 0.03; 4,091 +/- 3,068 vs 2,191 +/- 2,249, p = 0.02, respectively). In-hospital cardiac mortality was higher in patients with CRF than in patients without CRF (8.7% vs 0.7%, p < 0.001). The cumulative survival was 88% at 1 year and 65% at 3 years in patients with CRF and 99% and 97% in patients without CRF, respectively (p < 0.001). The incidence of re-hospitalization due to congestive heart failure was higher in patients with CRF (19% vs 1.3%, p < 0.0001). The cumulative survival in CRF was 93% at 1 year, 57% at 3 years in the medical treatment group and 87% and 75% in the invasive therapy group, respectively (p = 0.1). Patients with angina pectoris and CRF had a poor prognosis under the current treatment strategy. Newly developed therapeutic strategies, such as rotational atherectomy, minimally invasive direct coronary artery bypass surgery and combinations, will be necessary to improve the long-term prognosis for these patients.

Role of cytokines and adhesion molecules in ischemia and reperfusion in patients with acute myocardial infarction

Although acute myocardial infarction (AMI) may involve both plaque rupture and ischemia-reperfusion injury, the pathogenesis of these phenomena is unclear. To elucidate the pathogenesis of AMI, serial measurements of platelet activating factor (PAF), interleukin-6 and cell adhesion molecules were made in patients with AMI. The PAF levels were measured upon hospital admission and at 24 and 72h in 8 patients with AMI. Serum levels of interleukin-6, soluble E-selectin (sE-selectin), soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule- 1 (sVCAM- 1) were measured upon admission and at 24 h and 4 weeks in 30 patients with AMI and 15 patients with stable effort angina. PAF levels were higher in patients with AMI than in normal volunteers; the increased levels lasting at least 72h. In contrast, interleukin-6 increased at 24h. sE-selectin was elevated at admission and sVCAM-1 increased later. sE-selectin levels upon admission in patients with additional ST-segment elevation after reperfusion were significantly higher than those in patients without ST-elevation. In patients with AMI, the time-course of changes in blood levels of cytokines varied according to the individual substances. Although it is unclear what is the precise role of each of the cytokines in the pathophysiology of AMI, sE-selectin may be possibly related to the reperfusion injury in the infarcted myocardium.

Reduced expression of the alphabeta T-cell antigen receptor by alveolar T-cells

A previous study revealed that reduced expression (modulation) of the CD3 antigen is a common characteristic of alveolar T-cells in health and disease. As CD3 molecules are noncovalently bound to T-cell antigen receptors (TCR), it was hypothesized that modulation of TCR was also a feature of alveolar T-cells. To demonstrate this, lymphocytes from bronchoalveolar lavage fluid were stained with an anti-alphabeta TCR antibody and analysed by flow cytometry. The expression of alphabeta TCR by alveolar T-cells was evaluated by calculating mean fluorescence intensity (MFI) and was compared with alphabeta TCR expression by autologous blood T-cells. As anticipated from a previous study, modulation of TCR was observed not only in healthy volunteers but also in patients with pulmonary sarcoidosis, other pulmonary diseases, and nonpulmonary diseases. There were no significant differences in MFI of alveolar T-cells among the study groups. The degree of modulation assessed by the difference of MFI between blood and alveolar T-cells was greater for CD4+ cells than for CD8+ cells owing to the higher MFI of CD4+ blood T-cells. Coculture of alveolar macrophages with blood T-cells in vitro induced partial modulation of TCR. These results demonstrate the ubiquity of modulation of T-cell receptors on alveolar T-cells and suggest, in contrast to a previous report by other investigators that it is caused by some nonantigenic mechanism possibly inherent in the alveolar milieu. The implications of this phenomenon in in vivo immune responses of the lung need to be examined.

The distribution of sugar chains on the vomeronasal epithelium observed with an atomic force microscope

The distribution of sugar chains on tissue sections of the rat vomeronasal epithelium, and the adhesive force between the sugar and its specific lectin were examined with an atomic force microscope (AFM). AFM tips were modified with a lectin, Vicia villosa agglutinin, which recognizes terminal N-acetyl-D-galactosamine (GalNAc). When a modified tip scanned the luminal surface of the sensory epithelium, adhesive interactions between the tip and the sample surface were observed. The final rupture force was calculated to be approximately 50 pN based on the spring constant of the AFM cantilever. Distribution patterns of sugar chains obtained from the force mapping image were very similar to those observed using fluorescence-labeled lectin staining. AFM also revealed distribution patterns of sugar chains at a higher resolution than those obtained with fluorescence microscopy. Most of the adhesive interactions disappeared when the scanning solution contained 1 mM GaINAc. The adhesive interactions were restored by removing the sugar from the solution. Findings suggest that the adhesion force observed are related to the binding force between the lectin and the sugars distributed across the vomeronasal epithelium.

Three cases of spinal decompression sickness treated by U.S. Navy Treatment Table 7

For patients of type 2 decompression sickness, recompression therapy using U.S. Navy Treatment Table 6 (TT6) and its extensions is the most common means of treatment. However, some cases are resistant to the recompression therapy, and the outcome of TT6 is not always satisfactory. Although a new table, the U.S. Navy Treatment Table 7 (TT7) was described in 1985 in the U.S. Navy Diving Manual, to date few cases who were treated using TT7 have been reported. Here, we report three cases of spinal decompression sickness who received treatment according to TT7. Two were sports scuba divers, and the other a commercial diver. TT7 was applied later than 4 d after onset in all three cases; two patients were remarkably improved during the recompression therapy, while the other improved to a certain extent after additional repetitive TT6. Mild impairment of lung function, probably due to pulmonary oxygen toxicity, was observed on lung function testing in one case. In all cases, after additional TT6 and/or rehabilitation, patients were able to return to active daily living.

The purification and characterization of fatty acid hydroperoxide lyase in sunflower

Two fatty acid hydroperoxide lyases (HPO lyase I and II) were purified to apparent homogeneity from etiolated hypocotyls of sunflower (Helianthus annuus L.) by a combination of ion-exchange, hydrophobic interaction, and gel filtration chromatography. The two HPO lyases were separated during the hydrophobic interaction chromatography step, with HPO lyase I more hydrophilic than HPO lyase II. The estimated M(r) of both native HPO lyases was determined by gel filtration to be 200,000 and SDS-PAGE in the presence of 100 mM dithiothreitol showed that the enzyme was composed of a single 53 kDa peptide, suggesting that the enzyme exists as a tetramer in vivo. HPO lyase was also abundant in the cotyledons and green leaves. HPO lyases I and II from hypocotyl metabolized 13-hydroperoxylinoleic acid and 13-hydroperoxylinolenic acid to the same extent, but the green leaf enzyme was more than ten-fold more active with 13-hydroperoxylinolenic acid than 13-hydroperoxylinoleic acid. A difference spectrum between CO-bound and CO-unbound dithionite-reduced HPO lyase I showed an absorbance maximum at 452 nm, indicating that it was a cytochrome P450-type enzyme. The activities of HPO lyase I and II were significantly inhibited by nordihydroguaiaretic acid, sulfhydryl reagents, and piperonylbutoxide, which is a cytochrome P450 inhibitor.