[Assignment of differentiation-relevant cDNA RA538 on human chromosomes by fluorescence in situ hybridization]

OBJECTIVE

To localize the differentiation-relevant cDNA RA538 (3.8kb) onto the human chromosome 8q2.

METHODS

A modified non-isotopic labeling technique was used.

RESULTS

The cDNA RA538 was obtained by subtraction hybridization from human esophageal cancer cell line EC8712 induced by retinoic acid. Fluorescence in situ hybridization (FISH) using double-labeled probes showed clear and paired hybridization signals at the corresponding regions of both two chromatids in 18 out of 60 metaphases examined. While by single-labeling, only 7 were positive in 60 metaphases observed and the fluorescent spots were seen only at one chromatid.

CONCLUSION

The modified FISH protocol is useful for mapping cDNA sequences of a few kilobases.

Modulation of brain catecholamine absorbing proteins by dopaminergic agents

Catecholamine absorbing proteins (CATNAPs) are localized in the brain and thus far have no known biochemical and pharmacological characteristics consistent with other receptor proteins or metabolic enzymes in the central nervous system. The oxidative metabolism of catecholamines in the brain, especially the catabolism of dopamine and its conjugation with metabolic brain proteins, results in the production of highly toxic free radicals. Since such processes are implicated in the pathophysiology of various neurodegenerative diseases, including parkinsonism, and since CATNAPs bind catecholamines with high affinity, there is a need to further investigate if these novel proteins could play a protective role against these harmful catecholamine metabolites. In this study, we demonstrate the purification, pharmacological characterization and modulation of CATNAPs, as the first steps necessary to elucidate the function of these proteins in the brain. First, CATNAPs were identified from tissues using [3H]N-n-propylnorapomorphine (a specific dopamine receptor agonist) and [125I]6-hydroxy-5-iodo[N(N-2,4-dinitro-phenyl)- aminopropyl]1,2,3,4-tetrahydronaphthalene ([125I]DATN; a highly specific ligand synthesized in our laboratory). Three proteins, with molecular masses of 47, 40 and 26 kDa, were identified and purified, which allowed for the subsequent production of antibodies against each of these CATNAPs. The effects of in vivo chronic administration of several dopaminergic agents on CATNAPs were also examined by Western immunoblotting. L-3,4-Dihydroxyphenylalanine (L-DOPA) treatment in rats resulted in the increase of all of the three proteins, as compared to controls. Treatment in rats with the dopamine depleting agent, reserpine, produced a significant decrease in all of the three CATNAPs. In addition, the effects of direct administration of apomorphine, dopamine, epinephrine, isopropylnorepinephrine, norepinephrine, N-n-propylnorapomorphine and 6-hydroxydopamine on CATNAP levels in rats were examined. Interestingly, we observed an increase (as compared to control) of the 47, 40 and 26 kDa proteins in animals treated with dopamine, norepinephrine, N-n-propylnorapomorphine and apomorphine. In contrast, animals treated with 6-hydroxydopamine showed significant decreases in the levels of all three proteins. It is evident that as the concentration of catecholamines increases, there is a corresponding increase in the levels of CATNAPs in the brain. These results clearly demonstrate the pharmacological modulation of CATNAPs by dopaminergic agents and suggest their possible role in the cytoprotection against damage caused by free radicals generated by oxidative stress.

[Comparison of diet, physical activity and serum lipids between Chinese and Japanese: Chengdu-Fukuoka Study]

A detailed diet history was taken from 326 Chinese adults, 116 college students in Chengdu, China, and 300 Japanese adults and 4529 college students in Fukuoka, Japan. Both populations consume high carbohydrate and low fat diet, but the Chinese diet was higher in carbohydrate, cereal energy/total energy ratio and polyunsaturated fatty acids/saturated fatty acids ratio, and lower in protein, fat and animal fat/total fat ratio compared to the Japanese diet. Cholesterol intake was significantly lower in Chinese than in Japanese (P < 0.001). Physical activity index in Chinese was higher than that in Japanese. Serum lipids and lipoprotein cholesterols were measured in the adults of Chinese and Japanese. Except the serum triglycerids level in female, the total cholesterol, TG, high density lipoprotein-cholesterol and low density lipoprotein-cholesterol levels in Chinese adults were lower than those in Japanese adults (P < 0.001). Since cholesterol is the major predisposing factor for coronary heart disease and the results of our study show that a high carbohydrate and low fat diet can be effective in lowering the cholesterol level in blood it will be of interest to see which kind of oriental dietary may be a preventive against coronary heart disease.

[Antitussive, expectorant and anti-inflammatory effects of rhizoma Cynanchi stauntonii]

Experiments indicated that the ethanol extract and ether extract from Rhizoma Cynanchi Stauntonii showed obvious antitussive and expectorant effects in mice with stomach administration. The antitussive effect of ethanol extract was stronger than the expectorant effect. The water extract showed a certain expectorant effect but no marked antitussive effect with oral administration. Obvious anti-inflammatory effect was observed on croton oil-caused mouse ear swell with intraperitoneal injection.

Usefulness of intracardiac echocardiography in complex transseptal catheterization during percutaneous transvenous mitral commissurotomy

OBJECTIVE

To examine the utility of intracardiac echocardiography in guiding complex transseptal catheterization of patients undergoing percutaneous transvenous mitral commissurotomy.

DESIGN

We assessed this procedure in high-risk patients in whom transseptal catheterization is technically complex and more demanding.

MATERIAL AND METHODS

Fifteen patients with mitral stenosis were studied. Twelve patients had giant left atria (70 mm or more), two had atrial septal aneurysms, and one had severe kyphoscoliosis. A newly developed 8-F 10-MHz intracardiac transducer catheter was placed in the right atrium through an 8-F Mullins sheath inserted from the left femoral vein. Echocardiographic images were used to confirm the septal position of the Brockenbrough needle tip before septal punctures.

RESULTS

Transseptal puncture was successful and uncomplicated in all 15 patients. Use of intracardiac echocardiography eliminated the need for atrial angiography. Before transseptal puncture, the needle tip was identified to be in contact with the atrial septum, as an echogenic point with its acoustic shadow and septal indentation. In addition, in the two patients with aneurysms, puncture of the thin-walled aneurysms was avoided.

CONCLUSION

Intracardiac echocardiography facilitates safe complex transseptal catheterization in patients with mitral stenosis and giant left atria, atrial septal aneurysms, or severe kyphoscoliosis.

Percutaneous transvenous mitral commissurotomy in patients with mitral stenosis and coexistent hyperthyroidism

Percutaneous transvenous mitral commissurotomy (PTMC) was performed successfully without complications in 3 patients with severe mitral stenosis and hyperthyroidism. All 3 patients had pliable, noncalcified mitral valves. One patient who had been treated with methimazole for 6 months was still in a hyperthyroid state when she presented with intractable congestive heart failure and was found to have severe mitral stenosis. The heart failure improved immediately after PTMC, but the patient remained in New York Heart Association functional class 2 until a euthyroid state was achieved with I131 therapy. In the other 2 patients, hyperthyroidism was unsuspected at the time of PTMC. Unexpectedly suboptimal symptom improvement led to the diagnosis of hyperthyroidism 1 month after the intervention. In all 3 patients, PTMC resulted in an immediate hemodynamic and clinical improvement. However, complete clinical improvement occurred only when euthyroid state was achieved after antithyroid treatment. The present study suggests that PTMC is a safe and effective intervention modality in patients with coexisting hyperthyroidism and severe mitral stenosis. The procedure may be considered a therapeutic option in patients with hyperthyroidism and severe mitral stenosis.

[Dental appliances for the treatment of obstructive sleep apnea syndrome]

This study combined the use of cephalometrics and overnight polysomnographic monitoring to analyze the effects of a dental appliance on airway, sleep and respiratory conditions in 10 patients with obstructive sleep apnea. The findings indicated that horizontal and vertical mean changes in mandibular position while the appliance was worn were 1.73 mm and 9.30 mm, respectively, the mean superior airway space increased by 2.80 mm (P < 0.01), while the mean middle airway space increased by 6.75 mm (P = 0.01), the inferior airway space, however, didn't change significantly when the appliance was worn. The average Apnea Index decreased by 15.98 events per hour when the appliance was worn (P < 0.01), the average Respiratory Disturbance Index decreased from 39.43 to 6.62 events per hour in 9 of 10 patients (P < 0.01, one patient didn't have recording of hypoventilation). the lowest SaO2 value increased from 73.87% to 85.50% (P < 0.01). The reduction in the rate of airway obstructive events is attributed to the effect of appliance on the orophargneal structures. The dental appliance is a conservative, successful treatment alternative that could benefit patients with obstructive sleep apnea syndrome.

Atrial septal motion in effusive--constrictive pericarditis: transesophageal echocardiographic study and hemodynamic correlation

Transesophageal echocardiography was performed in 7 patients with effusive-constrictive pericarditis to analyze atrial septal motion(ASM). In 3 patients, the ASM was found to be normal with atrial septum (AS) moving toward the right atrium from ventricular mid-systole to early-diastole and toward the left atrium from mid-diastole to early-systole. Respiration had little effect on the ASM. In 2 patients, a brisk inversion of ASM toward the left atrium at ventricular early-to-mid systole was noted during inspiration. In the other 2 patients, a sustained ASM toward the left atrium during ventricular systole was found. In 4 of these 7 patients, hemodynamic studies were performed simultaneously with the transesophageal echocardiography. The ASM reflected the pressure gradient between the left atrium (as measured by pulmonary arterial wedge pressure) and the right atrium. The augmented ASM toward the left atrium occurred as left atrial pressure decreased markedly during inspiration. In conclusion, the ASM in patients with effusive-constrictive pericarditis showed 3 patterns: normal, sustained systolic motion toward the left atrium and a brisk systolic displacement toward the left atrium during inspiration. The ASM reflects changes in the interatrial pressure gradient.

[Antifebrile and anti-inflammatory effects of radix Cynanchi atrati]

The water extract of Radix Cynanchi Atrati used as intraperitoneal injection has been proved to have an obvious antifebrile++ effect on rat fever caused by 15% yeast suspension hypodermic injection as well as a significant anti-inflammatory effect. But the antiferbrile effect of its ethanol extract is not clear.

[Swallowing pattern in skeletal Class III malocclusion]

In this research, we compared the swallowing pattern in 33 normal occlusion adults with that in 29 skeletal Class III malocclusion adults, using computerized videofluoscopy. We found that: 1) in skeletal Class III malocclusion patients, the tongue, the hyoid bone and the mandible were in much lower position than those in normal people at postural position. The gap separation between the upper and lower lip was much larger. So was the space between the upper and lower molars. During swallowing, the tongue tip moved upward and backward, and continually moved back along with the backward movement of the tongue dorsum. This was the typical tongue retraction swallowing pattern in Class III malocclusion. The lips kept separation during deglutition, so did the molar region. 2) Abnormal swallowing pattern in skeletal Angle Class III patients was the adaptable change with the dentoalveolar disharmony, while the long time abnormal swallowing could change dentoalveolar structure.

[The early treatment of unilateral crossbite]

Fifteen unilateral crossbite patients of primary and mixed dentition with mandibular asymmetry were treated by transverse expansion using removable appliance. Posteroanterior cephalometric analysis was utilized before and after treatment. The results suggested that after the correction of unilateral crossbite, the deviation of midsagittal mandibular total lenth decreased significantly. According to this study, early treatment of unilateral crossbite is indicated.

[Study on LDL receptors of liver non-parenchymal cells in hypertriglyceridemic rats induced by high carbohydrate diet]

In the present study, hypertriglyceridemia was induced by feeding S. D. rats with high carbohydrate diet (carbohydrate accounting for 80% of total calorie) for 5 days. Rat liver parenchymal cells (PC) and non-parenchymal cells (NPC) were prepared by collagenase method. Human plasma LDL, VLDL and HDL were isolated by density gradient ultracentrifugation method. 125I-LDL was labelled by ICI method. 125I-LDL binding to rat liver PC and NPC were measured by Goldstein and Brown's method. The results showed that both rat liver PC and NPC had LDL receptors to bind, uptake and degradate 125I labelled human plasma LDL. The Bmax of 125I-LDL binding to NPC was 7-fold higher than that of PC (P < 0.01), but the Kd values remained unchanged. The Bmax of 125I-LDL binding to liver NPC from hypertriglyceridemic rats was significantly higher than that of NPC from the normal diet (carbohydrate accounting for 60% of total calorie) rats (435.4 + 100.0 vs 307.1 +/- 76.8 ng/mg cell protein, n = 6, P > 0.05), but there was no difference in Kd between the HTG rats and normal rats (18.1 +/- 4.1 vs 17.2 +/- 4.0 micrograms/ml n = 6, P > 0.05). These results suggest that the increase in fractional catabolic rate of LDL in patients with hypertriglyceridemia reported by Vega and Grundy might be induced by the increase in number of LDL receptor on liver non-parenchymal cells.

[Effect of native and oxidation-modified LDL, VLDL and HDL on the morphological appearance and phenotype of cultured human arterial smooth muscle cells]

The arterial smooth muscle cells (SMC) are the predominant type of cells in atherosclerotic lesions, and their proliferation plays an important role in the process of AS genesis. We established the primary culture and sub-culture method for human arterial SMC and observed the effects of LDL, VLDL, HDL, OX-LDL, OX-VLDL and OX-HDL on the morphological appearance and phenotype of cultured human arterial SMC. The results revealed that the cells cultured in the medium containing OX-LDL, OX-VLDL and OX-HDL (25 micrograms/ml) became more irregular with long finger-like projects and lacked a bipolar shape, and the characteristic "hills" and "valleys" disappeared. LDL and VLDL also had the influence but in smaller degrees. HDL did not have any effect. The SMC cultured in the presence of OX-LDL (25 micrograms/ml) had less myofilaments and more endoplasmic reticulua, Golgi and mitochondria in cytoplasm compared with the cells in control group under electronmicroscope. These results suggest that the atherogenic role of LDL, VLDL, OX-LDL, OX-HDL, and OX-VLDL are closely related to their stimulating effects on the modulation of phenotype of arterial SMCs from "contractile" towards "synthetic".

[Masticatory efficiency in skeletal class III malocclusion]

In this research, we used the Gunne's spectrophotometry method to measure the masticatory efficiency in 30 skeletal Class III patients and in 55 normal people. After groups comparing and step wise-regression analysis, we found that masticatory efficiency in Class III malocclusion group was much lower than that in normal occlusion group, and the masticatory efficiency in Class III malocclusion was about 60% of that in normal peoples. Masticatory efficiency in male was higher than that in female.

[Primary-explant method of culturing human arterial smooth muscle cells]

The primary culture of human arterial smooth cells (SMC) was performed successfully using the primary-explant method. The cells formed "hills and valleys" characteristic of SMC; the myofilament bundles were observed in the cytoplasm of the cells under an electron microscope and the cells were stained red with Ma's method. The growing character of 35th passage SMC kept unchanged. In addition, some problems concerning the culture of human arterial smooth muscle cells are discussed.

Properties of G-protein modulated receptor-adenylyl cyclase system in myocardium of spontaneously hypertensive rats treated with adriamycin

Properties of the receptor--G protein--adenylyl cyclase system were studied in spontaneously hypertensive rats (SHR) and age-matched normotensive Wistar-Kyoto rats (WKY) treated with adriamycin (ADR, 1 mg/kg per week) for 12 weeks. An identical dosing schedule caused a significantly greater decline in body weight gain and a marked elevation of plasma norepinephrine level in SHR than in WKY. A significant increase in the messenger RNA encoding Gi-alpha 2 was found in SHR+ADR group. The activity of the adenylyl cyclase stimulated by guanyliminodiphosphate [Gpp(NH)p] was decreased by 49% in SHR and 73% in SHR+ADR. However, stimulated activities of adenylyl cyclase by both sodium fluoride and forskolin remained unchanged. Functional level of stimulatory G-protein (Gs) as measured by reconstitution assay in sarcolemmal membrane was unaltered among different groups. Furthermore, the density of beta-adrenoceptor was significantly decreased without change of its affinity. Muscarinic receptors exhibited a three-site affinity distribution in SHR+ADR whereas other groups displayed only two-site affinity distribution. These results suggest that SHR exhibited a depressed myocardial adenylyl cyclase signaling system which may not be due to the functional uncoupling of beta-adrenoceptors from Gs but to the increased inhibitory G-protein (Gi) activity as demonstrated by the increased mRNA of Gi-alpha 2, increased inhibition of Gpp(NH)p-mediated adenylyl cyclase and the super high affinity for carbachol of the muscarinic receptors. Decreased beta-adrenoceptor density and functional alteration of Gi might be regarded as the predisposing factors for the increased susceptibility of myocardium of SHR to ADR.

Immunocytochemical localization of M2 muscarinic receptors in rat ventricles with anti-peptide antibodies

We produced antibodies against a synthetic peptide corresponding to amino acids 168-192 of the second extracellular loop of the M2 human muscarinic receptor in rabbits. In immunoblot, affinity-purified antibodies specifically recognized a major band of rat ventricular muscarinic receptor protein with a molecular weight of about 80 KD. This recognition could be blocked by pre-incubation with peptide. Moreover, with both light (LM) and electron microscopic (EM) immunocytochemistry techniques, muscarinic receptors were detected on sarcolemma and T-tubules of rat cardiomyocytes. In addition, immunoreactions were localized in membranes of capillaries. Likewise, these reactivities were abolished by pre-incubation with peptide. These results suggest that the antibodies against the second extracellular loop of human M2 muscarinic receptor could specifically recognize rat ventricular muscarinic receptor protein and could be a powerful tool to study the fate of this receptor under different pathological or physiological conditions.

Urgent/emergent percutaneous transvenous mitral commissurotomy

Urgent/emergent percutaneous transvenous mitral commissurotomy (PTMC) was performed in 10 patients (two men and eight women, aged 21 to 60 yr). All patients had arterial hypoxemia and four required mechanical respirators. PTMC was performed in the semi-recumbent position in four patients. The seven patients with pliable valves (group 1) achieved good hemodynamic and echocardiographic results after PTMC, but one died 2 wk later because of sepsis complicating preexisting pneumonitis. The two pregnant patients uneventfully delivered normal babies at term. There was continued clinical improvement in the six surviving patients at last follow-up at 11 to 39 mon (median 26). Of the three patients with calcified valves and severe subvalvular lesions (group 2), the premoribund patient in whom last-resort PTMC created severe mitral regurgitation died 3 days later of multiple organ failure. The other two patients underwent mitral valve replacement 1-6 days later because of lack of clinical improvement due to creation of severe mitral regurgitation and ineffective mitral valve dilation, respectively. In conclusion, urgent/emergent PTMC is feasible and safe. However, its outcomes are dictated by the status of diseased mitral valve and coexisting illness.

Percutaneous transvenous mitral commissurotomy in patients with severe kyphoscoliosis

Because transseptal catheterization is felt to be contraindicated in patients with severe kyphoscoliosis, there have been no reports of percutaneous transvenous mitral commissurotomy performed in such patients. This report describes percutaneous transvenous mitral commissurotomy in three patients with severe thoracic kyphoscoliosis, with special emphasis on the transseptal puncture technique. Biplane right atrial angiography and the contrast septal flush method are very useful in landmark selection for a safe transseptal puncture.

Electrochemical sensor for heparin: further characterization and bioanalytical applications

Further studies regarding the potentiometric response to heparin of polymeric membranes doped with lipophilic quaternary ammonium salts are reported. Among a wide range of membrane formulations examined, optimum response toward macromolecular heparin is achieved using tridodecylmethylammonium chloride as the active membrane component within poly(vinyl chloride) or poly(vinyl chloride)/(vinyl acetate) films plasticized with dioctyl sebacate. Although such membranes are shown to exhibit a typical Hofmeister potentiometric selectivity pattern toward small inorganic and organic anions, a very large and reproducible response to heparin at submicromolar levels is observed in the presence of physiological saline (0.12-0.15 M NaCl), as well as in citrated whole blood. Equal response on a mass basis occurs with fragments of heparin's as small as 2500 Da. Complexation of heparin's anionic sites by macromolecules that bind heparin with high affinity (e.g., protamine and poly(L-lysine)) reduces the membrane electrode's heparin response, indicating that the electrode detects biologically available (unbound) heparin levels in solution. Quantitative potentiometric titrations of protamine with porcine mucosa heparin followed by the sensor yield stoichiometric values in good agreement with the literature. The biomedical utility of the sensor is demonstrated by measuring its response in whole blood from patients undergoing open heart surgery before and after heparin therapy and correlating such response to conventional blood clotting time measurements.

Pulmonary valvuloplasty in adults using the Inoue balloon catheter

This report describes a new balloon pulmonary valvuloplasty technique using the Inoue balloon catheter performed in 14 consecutive adult patients, aged 17-47 years (mean 27). The mean right ventricular systolic pressure and the pulmonary valvular peak-to-peak systolic gradient decreased from 102 +/- 41 to 52 +/- 19 mm Hg (p = 0.001) and 81 +/- 40 to 7 +/- 7 mm Hg (p = 0.0002), respectively. An infundibular peak-to-peak systolic gradient either developed (n = 13) or increased (n = 1). None of the patients were treated with beta-adrenergic blockers before or after the valvuloplasty. Eight patients underwent repeat hemodynamic study 12-30 months (mean 17) after treatment, and had no evidence of valvular restenosis. The mean right ventricular systolic pressure and the mean infundibular peak-to-peak systolic gradient decreased, compared to the values immediately after valvuloplasty (54 to 40 mm Hg, p = 0.03, and 28 to 10 mm Hg, p = 0.03, respectively). The study suggests that pulmonary valvuloplasty in adults using the Inoue balloon catheter technique is feasible, safe, and effective.

Two-dimensional echocardiographic observation of dehiscence of mitral plication annuloplasty suture

Echocardiographic findings of dehiscent suture from mitral plication annuloplasty have not been described. We herein describe transthoracic two-dimensional echocardiographic findings of an abnormal linear echo stretching across the mitral annulus in the left atrium in a 69-year-old male. This abnormal linear echo was confirmed to be a dehiscent plication suture at surgery.

Prognosis after a first Q-wave myocardial infarction in ethnic Chinese people: a prospective study

The prognosis after a first Q-wave myocardial infarction was investigated in 206 Chinese patients of 65 years or younger who had a predischarge cardiac catheterization and coronary angiography. Three patients studied were lost to follow-up. In the remaining 203 patients with ages of between 28 and 65 years, 101 (49.8%) had 0- or 1-vessel disease, 56 (27.6%) had 2-, and 38 (18.7%) had 3-vessel disease. Significant left main coronary artery stenosis was noted in 8 (3.9%). During a mean follow-up of 33 months, 33 (16.3%) patients had 36 episodes of cardiac events, and 16 (7.9%) died of cardiac causes. Stepwise logistic regression analysis revealed that the left ventricular ejection fraction and left main coronary artery disease were predictors of cardiac mortality, while age and the extent of coronary artery disease were predictors of total cardiac events. There was no variable that could predict recurrence of myocardial infarction.

[A study of accuracy of multiple-unit one-piece castings of fixed bridge]

We studied how the accuracy of the three-unit and four-unit bridges is affected by the three different sprue programmes and heat-treatment. The results of experiments are as follows. 1. In the two types of fixed bridge the accuracy of the lateral pouring sprue programme is greater than that of the top-pouring and bottom-pouring sprue programmes. 2. After the heat-treatment of the casting, the stresses are distributed again, so the accuracy of the casting becomes lesser. 3. The change in the measurement of the total and pontic lengths of multiple-unit fixed bridges generally causes a "fork shape" deformity.

Familial aggregation of oesophageal cancer in Yangcheng County, Shanxi Province, China

Oesophageal cancer is the second most common cause of cancer death in China and is particularly prevalent in northern China. Genetic factors have been studied less than environmental factors in the aetiology of this disease. This study was conducted to evaluate familial aggregation of oesophageal cancer. All households in Yangcheng County were interviewed in 1979 to determine family history of oesophageal cancer. In 1989, vital status for all family members from three Yangcheng villages was determined and re-interviews were conducted among families who reported a positive family history of oesophageal cancer in 1979. Risk of oesophageal cancer was evaluated by comparing family and individual rates of oesophageal cancer during the 1979-1989 interval stratified by the number of family members with oesophageal cancer prior to 1979. More families with prior oesophageal cancer history reported new oesophageal cancer deaths during the follow-up period than families without prior history (19% versus 5%). Oesophageal cancer rates increased with increasing positivity of family history, and adjustment for other risk factors did not substantially alter this result. We conclude that these data provide evidence for familial aggregation of oesophageal cancer.

Contrast transesophageal echocardiographic demonstration of coronary artery fistula within left atrial appendage thrombus in mitral stenosis

Coronary neovascularization and fistula formation arising from the left circumflex artery demonstrated by coronary angiography is a specific sign for the presence of left atrial appendage thrombus in patients with mitral stenosis. However, the fistula drainage site in the left atrium in relation to the thrombus cannot be ascertained by the angiographic method. We performed transesophageal echocardiography simultaneously with coronary angiography in five patients with severe mitral stenosis and left atrial appendage thrombus. The angiography showed coronary neovascularization and fistula arising from the left circumflex artery in three patients. In these three patients, the transesophageal echocardiography confirmed the presence of a coronary fistula by identifying contrast exuding from the surface of the thrombus. Thus we have shown for the first time the usefulness of contrast transesophageal echocardiography in imaging the exact drainage site of coronary artery fistula from left atrial appendage thrombus.

A strategy for isolating differentiation-inducing complementary DNAs from human esophageal cancer cell line treated with retinoic acid

Treatment of the human esophageal cancer cell line EC8712 with retinoic acid (RA) stopped the cell growth significantly and gave rise to terminal differentiation of the cells characterized by increased expression of involucrin gene. Two cDNA libraries were constructed from the parental and RA-treated cells respectively. Repeated subtractive hybridization of single-stranded plasmid DNA prepared from pooled colonies of cDNA library of the parental cells with cDNA probe generated from the RA-treated cells exhausted sequences common to both libraries of the cell. The unhybridized cDNA probe represented, therefore, the genes activated after RA-treatment. By using these enriched cDNAs as probe to screen the cDNA library constructed from the RA-treated cells thirty-nine positive colonies were obtained, of which two were specifically due to RA-induction. One of these two cDNA clones, designated as pRA538, has undergone further analysis and shown differentiation-inducing effect on parental cancer cells. A novel strategy for cloning genes involved in terminal differentiation of cancer cells is developed.

Developmental expression of the glial fibrillary acidic protein (GFAP) gene in the mouse retina

1. In the nervous system, Glial fibrillary acidic protein (GFAP) is a well-known, cell type-specific marker for astrocytes. 2. In the mammalian retina, Muller cells, the major class of retinal glia, do not express GFAP or contain only low amounts of this protein. In retinas with photoreceptor degeneration, however, high levels of GFAP are found. It is possible that GFAP synthesis in these retinas could result from "dedifferentiation" of Muller cells as a consequence of disruption of normal neuron-glia interactions. 3. We have carried out immunocytochemical and in situ hybridization studies to examine whether GFAP or its mRNA is expressed by retinal cells early in embryonic development. 4. Our results show that GFAP-containing cells, which are probably astrocytes, are found only in the ganglion cell and nerve fiber layers and that these cells appear after postnatal day-1 (P-1) and continue to form until P-10. 5. Astrocyte formation starts from the optic disc and moves toward the periphery of the retina at a rate of approximately 160-200 microns per day. 6. An unexpected result from these studies is that GFAP mRNA levels are high in the first week of birth and decline rapidly as the animal develops. 7. Finally, we did not find either GFAP or GFAP mRNA in retinal cells other than astrocytes during normal development.

Short- and long-term results of catheter balloon percutaneous transvenous mitral commissurotomy

Percutaneous transvenous mitral commissurotomy (PTMC) was performed in 219 patients with symptomatic, severe rheumatic mitral stenosis. There were 59 men and 160 women, aged 19 to 76 years (mean 43). Pliable, noncalcified valves were present in 139 (group 1), and calcified valves or severe mitral subvalvular lesions, or both, in 80 patients (group 2). Atrial fibrillation was present in 133 patients (61%) and 1+ or 2+ mitral regurgitation in 59 (27%). Technical failure occurred with 3 patients in our early experience. There was no cardiac tamponade or emergency surgery. The only in-hospital death occurred 3 days after the procedure in a group 2 premoribund patient in whom last-resort PTMC created 3+ mitral regurgitation. Mitral regurgitation appeared or increased in 72 patients (33%); 3+ mitral regurgitation resulted in 12 patients (6%). There were 3 systemic embolisms. Atrial left-to-right shunts measured by oximetry developed in 33 patients (15%). Immediately after PTMC, there were significantly reduced (p = 0.0001) left atrial pressure (24.2 +/- 5.6 to 15.1 +/- 5.1 mm Hg), mean pulmonary artery pressure (39.7 +/- 13.0 to 30.6 +/- 10.9 mm Hg) and mitral valve gradient (13.0 +/- 5.1 to 5.7 +/- 2.6 mm Hg). Mitral valve area increased from 1.0 +/- 0.3 to 2.0 +/- 0.7 cm2 (p = 0.0001) and cardiac output from 4.4 +/- 1.4 to 4.7 +/- 1.2 liters/min (p less than 0.01). The results mirrored clinical improvements in 209 patients (97%). Multivariate analysis showed an echo score greater than 8, and valvular calcification and severe subvalvular lesions as independent predictors for suboptimal hemodynamic results.(ABSTRACT TRUNCATED AT 250 WORDS)

[The role of arterial collagen nonenzymatic glycosylation (NEG) in the pathogenesis of diabetic macroangiopathy]

In this study, we found that 5-Hydroxymethylfurfural (5-HMF) released from aortic collagen was significantly increased in diabetic rats with diabetic duration of 4, 8, 12 weeks (P less than 0.001, P less than 0.001, P less than 0.001). Collagen-link fluorescence (CLF) was also increased in diabetic rats P less than 0.005, P less than 0.05, P less than 0.01 respectively). Mean collagen-content was higher in diabetic rats than in the controls (P greater than 0.05, P less than 0.01, P less than 0.01 respectively). In diabetic rats, the amount of 5-HMF was related to plasma glucose concentration (r = +0.52, P less than 0.01) and CLF (r = +0.58, P less than 0.01). There was a positive correlation between CLF and collagen-content in diabetic rats (r = +0.45, P less than 0.05). These results suggest that NEG do occur in arterial collagen. Advanced glycosylation end products could participate in glucose derived cross-link formation and accumulate through the lifetime of collagen, which may change the function and structure of collagen. The increase of collagen content of arterial wall in diabetic rats may probably have resulted from excessive formation of cross-links.

[Effects of high carbohydrate and high fat diet on plasma apolipoproteins AI, AII, B100, CI, CII, CIII and E in normal and hypertriglyceridemic humans]

Effects of high carbohydrate (CHO) and high fat diet on plasma apolipoproteins (apo) AI, AII, B100, CI, CII, CIII and E were assessed in 10 healthy subjects and 10 patients with endogenous hypertriglyceridemia. High CHO diet consisted of 80% CHO, 5% fat and 15% protein of total calories, and high fat diet consisted of 40% CHO, 45% fat and 15% protein. After 5 days normal diet (60% of total calories from CHO, 25% from from fat and 15% from protein), the subjects studied received sequentially high CHO diet and normal diet for 5 days and high fat diet and normal diet for 5 days. Fasting blood samples were drawn on days 1, 3, and 5 of high CHO and high fat diet period, and 5 days after taking normal diet. Results showed that fasting plasma apo AI slightly decreased (P less than 0.01) on day 3 of the high CHO diet period and slightly increased (P less than 0.01) on day 3 of the high fat diet period, plasma apo AII increased after intake of high CHO diet, but no changes were observed after the subjects were placed on high fat diet. Fasting plasma apo B100 decreased (P less than 0.001) in hypertriglyceridemics on the 3rd day of the high CHO diet, but no differences were noted in normal subjects on the same diet. On the 3rd day of the high fat diet period, apo B100 increased (P less than 0.01) in normal subjects, but no changes were found in hypertriglyceridemics. Apo CII and CIII levels declined during the high CHO diet period but increased in normal subjects after intake of high fat died.(ABSTRACT TRUNCATED AT 250 WORDS)

Localization of laminin B1 mRNA in retinal ganglion cells by in situ hybridization

In the nervous system, neuronal migration and axonal growth are dependent on specific interactions with extracellular matrix proteins. During development of the vertebrate retina, ganglion cell axons extend along the internal limiting (basement) membrane and form the optic nerve. Laminin, a major component of basement membranes, is known to be present in the internal limiting membrane, and might be involved in the growth of ganglion cell axons. The identity of the cells that produce retinal laminin, however, has not been established. In the present study, we have used in situ hybridization to localize the sites of laminin B1 mRNA synthesis in the developing mouse retina. Our results show that there are at least two principal sites of laminin B1 mRNA synthesis: (a) the hyaloid vessels and the lens during the period of major axonal outgrowth, and (b) the retinal ganglion cells at later development stages. Müller (glial) cells, the major class of nonneuronal cells in the retina, do not appear to express laminin B1 mRNA either during development or in the adult retina. In Northern blots, we found a single transcript of approximately 6-kb size that encodes the laminin B1 chain in the retina. Moreover, laminin B1 mRNA level was four- to fivefold higher in the postnatal retina compared to that in the adult. Our results show that in addition to nonneuronal cells, retinal ganglion cells also synthesize laminin. The function of laminin in postnatal retinas, however, remains to be elucidated. Nevertheless, our findings raise the possibility that neurons in other parts of the nervous system might also synthesize extracellular matrix proteins.

Figure-eight kinking of the aorta (pseudocoarctation) coexistent with coarctation

An asymptomatic young man presented with a cardiac murmur and hypertension only in the right arm. Angiograms showed kinking of the aortic arch with a figure-eight appearance consistent with pseudocoarctation. Before the kinked segment, also demonstrated were a stenotic lesion in the aortic arch proximal to the left carotid artery and profound collateral circulations in the right thorax. These findings strongly suggested a rare combination of pseudocoarctation and true coarctation. His hypertension was corrected following surgery with a bypass graft between the ascending aorta and the abdominal aorta.

Atrial natriuretic peptide and vasopressin during percutaneous transvenous mitral valvuloplasty and relation to renin-angiotensin-aldosterone system and renal function

To study the relation between plasma atrial natriuretic peptide (ANP) and cardiac pressure, and to assess the pathophysiologic significance of ANP in water and electrolyte metabolism, the changes in plasma levels of ANP and arginine vasopressin (AVP) were examined in 11 patients with mitral stenosis who underwent percutaneous transvenous mitral valvuloplasty, and compared with the changes in the renin-angiotensin-aldosterone system and renal function. Immediately after valvuloplasty, plasma ANP levels decreased significantly with a concomitant decrease in mean pressures in the left atrium, the pulmonary artery and the right atrium. Plasma ANP levels decreased to the normal range in 4 of the 6 patients with normal sinus rhythm, while all 5 patients with atrial fibrillation had higher levels despite a similar degree of decrease in atrial pressure. There were significant positive correlations between plasma ANP levels and the mean left atrial pressure (r = 0.61, p less than 0.01), the mean pulmonary arterial pressure (r = 0.49, p less than 0.01) and the mean right atrial pressure (r = 0.54, p less than 0.01). The mean plasma AVP levels, on the other hand, showed a transient increase after valvuloplasty from 0.5 +/- 0.1 to 1.2 +/- 0.4 pg/ml (p less than 0.05). The mean plasma renin activity (1.3 +/- 0.3 vs 2.7 +/- 0.8 ng/ml/hr, p less than 0.05) and plasma aldosterone concentration (8.6 +/- 2.3 vs 17.2 +/- 5.2 ng/dl, p less than 0.05) also increased significantly 30 minutes after valvuloplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic and clinical efficacies of catheter balloon percutaneous transvenous mitral commissurotomy: experience of 100 patients with rheumatic mitral stenosis

From January 1987 to December 1988, 100 patients with symptomatic severe rheumatic mitral stenosis underwent percutaneous transvenous mitral commissurotomy (PTMC). The patients included 32 males and 68 females, aged 19-71 years (mean of 41). Mild mitral regurgitation (grade 1 or 2) was present in 23 patients and a history of thromboembolism in 12. One patient had had mitral restenosis after surgical open mitral commissurotomy 9 years earlier. The mitral valve was successfully dilated in 97 patients. PTMC resulted in immediate improvements in hemodynamic measurements. The left atrial pressure decreased from 24.5 +/- 5.3 to 14.8 +/- 5.2 mmHg (p less than 0.001), the mean mitral transvalvular gradient from 13.8 +/- 4.8 to 5.0 +/- 2.8 mmHg (p less than 0.001), and the mean pulmonary artery pressure from 38.8 +/- 12.0 to 30.6 +/- 10.3 mmHg (p less than 0.001). The mitral valve area increased from 1.1 +/- 0.3 to 2.2 +/- 0.8 cm2 (p less than 0.001). The cardiac output increased from 4.5 +/- 1.2 to 4.84 +/- 1.2 L/min (p less than 0.05). The right atrial pressure did not change significantly after PTMC (6.5 +/- 3.8 vs 6.4 +/- 4.0 mmHg). The mitral valve area measured by 2-D echocardiograms increased from 1.04 +/- 0.48 to 1.88 +/- 0.66 cm2 after PTMC (p less than 0.001). All 97 patients were followed for 6-24 months (median of 13) after the PTMC. After an initial recovery period of 1-2 weeks, all patients reported improvements in symptoms and in New York Heart Association (NYHA) functional class by at least one class. A comparison between treadmill exercise test durations before, and 3 months after PTMC, showed an increase from 9.1 +/- 4.3 to 15.4 +/- 3.8 minutes (n = 60; p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Localization of L-glutamic acid decarboxylase mRNA in cat retinal horizontal cells by in situ hybridization

Retinal horizontal cells receive synaptic input from photoreceptors and provide a pathway for lateral interactions in the vertebrate retina. In nonmammalian retinas, the H1 horizontal cells appear to use gamma-amino butyric acid (GABA) as their neurotransmitter. The transmitter used by mammalian horizontal cells, however, remains to be identified. In the present study, we have employed in situ hybridization to examine whether cat retinal horizontal cells contain L-glutamic acid decarboxylase (GAD) mRNA and hence might use GABA as their transmitter. In the cat retina, labeled cell bodies were found in the inner nuclear layer and the ganglion cell layer. No labeled cells were found in the photoreceptor layer. In the inner nuclear layer, labeled somata were present at two locations. The majority of them (approximately 72%) were located in the vitread side of the inner nuclear layer bordering the inner nuclear layer/inner plexiform layer boundary. A second class of labeled cells in the inner nuclear layer (approximately 20%) had larger somata and were present at the inner nuclear layer/outer plexiform layer boundary. Double labeling experiments with antisera to parvalbumin, a horizontal cell marker, showed that these perikarya belonged to horizontal cells. RNA blot analysis showed that cat retina contains a single species of GAD mRNA that is about 4 kb in size. These data show that in addition to GABAergic amacrine, displaced amacrine, and interplexiform cells described previously, horizontal cells contain GAD mRNA and may use GABA as their neurotransmitter. Hence, GABA may be a transmitter that is involved in lateral inhibition in both nonmammalian and mammalian retinas.

Localization of L-glutamic acid decarboxylase mRNA in monkey and human retina by in situ hybridization

Immunocytochemical studies with gamma-aminobutyric acid (GABA) antibodies and glutamic acid decarboxylase antibodies have shown that the primate retina contains GABAergic amacrine, interplexiform, and displaced amacrine cells. In addition, subpopulations of photoreceptors and horizontal cells have also been suggested to be GABAergic in this retina. In the present study, we have used in situ hybridization to localize GABAergic neurons in human and monkey retinas. In situ hybridizations were carried out with 35S-labeled DNA and RNA probes derived from human and cat glutamic acid decarboxylase cDNA clones. In the monkey retina, labeled cells were present in the inner nuclear and ganglion cells layers. The outer nuclear layer or the inner segment layer had only background levels of labeling. In the inner nuclear layer, all labeled somata were located in the vitread-half bordering the inner nuclear layer/inner plexiform layer boundary. These cells constituted approximately 83% of all labeled cells. Labeled cells were also seen in the ganglion cell layer. In the human retina, labeled somata were observed only in the inner nuclear and the ganglion cell layers. In the inner nuclear layer, the majority of labeled cells were located close to the inner nuclear layer/inner plexiform layer boundary although a minor population of labeled somata (approximately 20%) were found deeper in the inner nuclear layer. The distribution of glutamic acid decarboxylase mRNA-containing cells we observed is in good agreement with the known location of GABAergic neurons. We, however, did not find glutamic acid decarboxylase mRNA in either horizontal cells or photoreceptors in monkey and human retina.

Subcellular localization of an intermediate filament protein and its mRNA in glial cells

Eucaryotic mRNAs are generally localized in the cell body, where most protein synthesis occurs. We have found that mRNAs encoding the glial intermediate filament protein are spatially distributed in the glial cell cytoplasm close to the location of the glial filaments. Whereas the glial filament protein mRNA was located predominantly in the distal process, actin mRNA was found almost exclusively in the apical portion of the glial cell. This pattern of mRNA localization might provide a mechanism for synthesis of proteins in specific subcellular compartments by mRNA translation locally.

Transcriptional activation of an intermediate filament protein gene in mice with retinal dystrophy

We are interested in understanding neuronal interactions that regulate expression of specific genes in glial cells in the nervous system. In the normal mouse retina, the glial intermediate filament protein (GFAP) is not detectable in Müller cells, the predominant glial cells in the retina. Photoreceptor degeneration resulting from retinal degeneration (rd) mutation or environmental light damage, however, leads to the appearance of GFAP in Müller cells. We have investigated the mechanism underlying GFAP accumulation in these retinas. Western blotting analysis, steady-state mRNA level comparisons, and nuclear run-on assays show that transcription of the GFAP gene is activated in these retinas. In situ hybridizations with retinal sections and solitary Müller cells establish that GFAP mRNA levels are elevated in Müller cells. These results show that disruption of neuron-glia interactions resulting from photoreceptor degeneration leads to activation of the GFAP gene in glial cells of mice with retinal dystrophy. The functional significance of this glial response and the need for GFAP expression remain to be understood.

Rapid fall in elevated plasma atrial natriuretic peptide levels after successful catheter balloon valvuloplasty of mitral stenosis

To determine whether an acute fall in atrial pressure decreases the secretion of atrial natriuretic peptide in man, changes in the plasma levels of this peptide were studied after catheter balloon valvuloplasty of the mitral valve. Ten patients with severe mitral stenosis were included in the study. The valvuloplasty resulted in an immediate reduction in left atrial pressure and an increase in the mitral valve area. Decreases in right atrial pressure were inconsistent and less significant. Plasma atrial natriuretic peptide levels, which were elevated before the valvuloplasty, decreased significantly in all 10 patients at 15 minutes after the valvuloplasty and reached lower plateaus at 30, 45, and 60 minutes after the procedure. In the seven patients studied for a longer period, both plasma atrial natriuretic peptide levels and the left atrial pressure remained reduced 24 hours after the valvuloplasty. Plasma atrial natriuretic peptide levels before and 30 to 60 minutes after the valvuloplasty were positively correlated to simultaneously determined left and right atrial pressures. These results indicate that atrial stretch caused by increased atrial pressure is an important stimulus for atrial natriuretic peptide release in man. "De-stretching" of the myocytes of the atria results in rapid inhibition of atrial natriuretic peptide secretion.

Early diagnosis of acute myocardial infarction by myoglobin latex agglutination test

Early elevation of the serum myoglobin level in acute myocardial infarction (AMI) has been noted for years. In this study, 39 patients admitted to the Coronary Care Unit with acute chest pain within 72 hours (mean 12 +/- 15 hours) or electrocardiographic changes suspected of acute myocardial infarction had a serum myoglobin latex agglutination test to evaluate its diagnostic accuracy in acute myocardial infarction. Of these 39 patients, 24 had documented acute myocardial infarction as their final diagnosis. By the time of admission, 18 of the 24 cases with infarction had positive myoglobin tests (sensitivity 75%). Of those 15 cases without myocardial infarction, 13 had negative myoglobin tests (specificity 87%). If only those 17 cases admitted within 5 hours of the onset of chest pain were analyzed, the serum myoglobin test became positive in 8 of 10 cases with documented AMI but the 2 cases with negative results turned positive 2 hours later (sensitivity 80% to 100%). Due to the fact that myoglobin tests were negative in all other 7 cases without infarction, the specificity was 7/7 (100%). In contrast, the creatine phosphokinase isoenzyme study was positive only in 3 of these 10 patients with documented AMI in the first blood sample taken during admission. In conclusion, the serum myoglobin latex agglutination test is a quick and reliable method that helps in the early diagnosis of acute myocardial infarction.