[Pulmonary function tests and their clinical significances on outside of textbooks]

Pulmonary functions are classified two kinds of functions which are respiratory and non-respiratory. We explained new clinical significant results by looking at the usual respiratory pulmonary function tests and devices in this paper. We found two new indexes on uneveness of ventilation by analyzed compartments of forced expiratory curves(Tiffneu curves) and at improvement of CO single breathing method on diffusing capacity test. We found new index on bronchial anaphylaxis for bronchial asthma by time constant measured from forced expiratory curves, also. We found new index on ventilatory efficiency at developing the automatic respiratory resistance meter by the forced oscillation method of Du Bois, too.

Calorie restriction reduced blood pressure in obesity hypertensives by improvement of autonomic nerve activity and insulin sensitivity

Association between obesity and hypertension has been well recognized. A reduction in the body weight of over-weight hypertensive patients is a recommended lifestyle modification. The purpose of our study is to examine the relationship of insulin sensitivity and autonomic nervous activity with reduction of blood pressure by the calorie restriction. We evaluated the heart rate variability, nocturnal change of blood pressure and insulin resistance before and after a short-term low-calorie diet in 12 overweight essential hypertensives. After a week of standard diet (2000 kcal), 2 weeks of low-calorie diet (800 kcal) with normal sodium content induced a significant reduction in body mass index, triglyceride, fasting immunoreactive protein, homeostasis model assessment as an index of insulin resistance, and urinary excretion of sodium and potassium. Systolic blood pressure was significantly reduced both in daytime and night-time after the low-calorie diet (daytime, 134.5+/-6.0 to 122.0+/-4.1 mmHg; night-time, 126.8+/-5.2 to 113.4+/-7.2 mmHg). In daytime, diastolic blood pressure was also reduced (90.3+/-2.1 to 88.1+/-4.8 mmHg). Although heart rate was not significantly reduced, a rise of high frequency in night-time (346+/-82 to 572+/-108 ms2) and a fall of low frequency/high frequency in day-time (3.5+/-0.4 to 2.6+/-0.1) was significant after a low-calorie diet. In conclusion, weight loss by low-calorie diet with a constant intake of sodium, reduced blood pressure in obese hypertensives by improvement of vagal nervous activity and insulin resistance.

[Probability of the standardization of control survey in local medical association]

This report discusses about the probability of the standardization of external quality control (control survey) in local medical area such as prefecture size. For example, our control survey by Hiroshima medical association in Hiroshima prefecture is selected and shown on their effort to the standardization of the control survey. This Hiroshima control survey is continuing for 27 years and its purpose is the improvement of the differences between laboratory facilities. For the all standardization of control survey system, tests, devices and reagents, the recent reports of Hiroshima control survey shows that the reference methods by Japan Society of Clinical Chemistry (JSCC) and the enzyme reference materials by Japan Committee of Clinical Laboratory Standardization (JCCLS) are very useful for the improvement of the differences between laboratory facilities in Hiroshima Prefecture.

Intramolecular 1,3-dipolar cycloaddition strategy for enantioselective synthesis of FR-900482 analogues

[reaction: see text] Enantioselective synthesis of FR-900482 analogues is described. The key reaction of the synthesis is intramolecular 1,3-dipolar cycloaddition of a highly functionalized nitrile oxide with complete stereo- and regioselectivities to construct the eight-membered benzazocine ring.

[Relationship between flow volume curve and CT findings in non-smoking patients with long histories of bronchial asthma]

AIM

This study was conducted to verify whether bronchial asthma (BA) alone causes pulmonary emphysema (PE), and to examine the computed tomography (CT) findings in non-smokers with BA demonstrating the flow volume curve (FV curve) characteristic of PE.

SUBJECTS AND METHODS

Non-smoking patients with a history of BA for more than 20 years were divided into 2 groups: the dogleg pattern group (n = 5), with an FV curve characteristic of PE, and the concave pattern group (n = 16) with an FV curve characteristic of BA. CT scans was performed using CT values (level, 900 H.U.; width, 400 H.U.) that facilitate detection of a low attenuation area (LAA), and using conventional CT values (level, 700 H.U.; width, 1,300 H.U.). LAA (including air trapping), thickness of the bronchial wall, and partial atelectasis were compared between the 2 groups.

RESULTS

PE was not detected, although air trapping was found in all subjects. The thickness of the airway was greater in the dogleg pattern than in the concave pattern. The incidences of air trapping and partial atelectasis were higher in the former than in the latter.

DISCUSSION

BA alone may not cause PE. Some BA patients without PE show the FV curve characteristic of PE, reflecting an increase in the thickness of the airway wall and a decrease in the pulmonary ventilation probably due to the air trapping and the partial atelectasis.

IL-6 attenuates apoptosis, while neither IL-6 nor IL-10 affect the numbers or protease phenotype of fetal liver-derived human mast cells

BACKGROUND

The combination of recombinant human stem cell factor (rhSCF), rh interleukin (IL)-6 and rhIL-10 was reported to be optimal for mast cell development from cord blood progenitors and to induce chymase expression in all such mast cells earlier in their development than tryptase.

OBJECTIVE

The effects of rhIL-6 and rhIL-10 in various combinations on the rhSCF-dependent development of human mast cells from fetal liver progenitors were examined in serum-free media.

METHODS

Dispersed fetal liver cells were cultured in serum-free AIM-V medium with rhSCF alone, or with combinations of rhIL-6 and rhIL-10. Tryptase and chymase expression, surface Kit expression, metachromasia with toluidine blue and apoptosis were measured.

RESULTS

Neither rhIL-6 nor rhIL-10 nor the two interleukins together, when included from day 0 of culture, affected the number or protease phenotype of mast cells at 1 or 3 weeks. Expression of tryptase paralleled the appearance of metachromasia and surface Kit, both of which preceded chymase expression, regardless whether a rabbit polyclonal or mouse monoclonal anti-chymase antibody preparation was used. On the other hand, rhIL-6 markedly attenuated baseline levels of apoptosis in the presence of rhSCF as well as apoptosis occurring after withdrawal of rhSCF, whereas rhIL-10 had no effect.

CONCLUSION

RhIL-6 protected fetal liver-derived mast cells from apoptosis, particularly after withdrawal of rhSCF, but neither rhIL-6 nor rhIL-10 nor the combination of these interleukins affected the numbers or protease phenotype of these mast cells.

Vitamin D receptor gene polymorphism is associated with serum total and ionized calcium concentration

Restriction fragment length polymorphisms of the vitamin D receptor gene have recently been reported to be associated with changes in bone mineral density. Alterations in systemic calcium balance and Ca-regulating hormones such as 1,25(OH)2 vitamin D3 and parathyroid hormone have been demonstrated in essential hypertension. We investigated the relationship between polymorphisms of the vitamin D receptor gene and systemic Ca metabolism in patients with essential hypertension and in normotensives. We compared 147 subjects with essential hypertension and 100 normotensive control subjects. The genotype distribution and derived allele frequencies for the vitamin D receptor gene were similar in the two groups (genotype bb/Bb/BB and allele B/b: 60.1/32.6/7.2 and 0.24/0.76 in hypertensives vs. 56.0/36.0/8.0 and 0.26/0.74 in normotensive subjects). Serum concentrations of total Ca in the bb, Bb, and BB groups were, respectively, 4.5+/-0.3 vs. 4.5+/-0.4 vs. 4.4+/-0.5 mmol/l in normotensives and 4.6+/-0.3 vs. 4.6+/-0.4 vs. 4.4+/-0.5 mmol/l in hypertensives. Ionized Ca levels were 1.17+/-0.04 vs. 1.16+/-0.04 vs. 1.15+/-0.04 mmol/l in normotensives and 1.16+/-0.04 vs. 1.16+/-0.04 vs. 1.14+/-0.05 mmol/l in hypertensives, respectively. These results indicate that the BB genotype of the vitamin D receptor gene is associated with lower serum Ca levels but is not a useful predictive marker for the development of essential hypertension in Japanese subjects.

Apoptosis is not increased in myocardium overexpressing type 2 angiotensin II receptor in transgenic mice

To determine whether angiotensin type 2 (AT(2)) receptor stimulation induces apoptosis in cardiomyocytes in vivo, we developed transgenic mice overexpressing the AT(2) receptor in a cardiac-specific manner, using the alpha-myosin heavy-chain promoter. Ten- to 12-week-old male homozygous transgenic mice (n=44) and wild-type mice (n=44) were used. Both transgenic and wild-type mice were given either saline (control), a subpressor dose of angiotensin II (100 ng. kg(-1). min(-1)), a pressor dose of angiotensin II (1000 ng. kg(-1). min(-1)) for 14 days, a pressor dose of angiotensin II for 28 days to investigate the effects of stimulation on both angiotensin type 1 (AT(1)) and AT(2) receptors, the AT(1) antagonist L158809 alone, or a combination of angiotensin II (1000 ng. kg(-1). min(-1)) and L158809 for 14 days to investigate the effects of selective AT(2) receptor stimulation. Apoptosis was analyzed in paraffin-embedded ventricular sections by the terminal deoxynucleotidyl-transferase-mediated dUTP nick-end labeling (TUNEL) technique. In both transgenic and wild-type mice, administration of a subpressor dose of angiotensin II, L158809, or a combination of angiotensin II and L158809 did not significantly affect the tail-cuff blood pressure or heart-to-body weight ratio, whereas administration of a pressor dose of angiotensin II for 14 or 28 days significantly increased blood pressure and the heart-to-body weight ratio. However, there was no statistical difference between the effects of angiotensin II in transgenic and wild-type mice. The number of TUNEL-positive nuclei was approximately 0 to 10 per 100 000 cardiomyocytes, with no difference between transgenic and wild-type mice, regardless of saline infusion or any stimulation. In infarcted canine myocardial tissue sections for positive control, the number of TUNEL-positive nuclei was increased by 13.8 to 19.1 times compared with those in the noninfarcted myocardium. In conclusion, angiotensin II infusion for a period of 28 days failed to induce cardiomyocyte apoptosis regardless of the presence or absence of cardiac AT(2) receptor overexpression. It is unlikely that in mice the AT(2) receptor is a strong signal to induce cardiomyocyte apoptosis in vivo.

[Topics of clinical physiological tests--pulmonary function--proposal of physio-chemical tests]

Pulmonary functions are classified as respiratory and non-respiratory. Although the mechanisms of non-respiratory pulmonary function have already been established, no new tests of respiratory pulmonary function have been developed for a long time. Thus, we report here a new analytic test of respiratory pulmonary functions. The new analytic method is physio-chemical analysis, in which the chemical factors of lungs are estimated from the physiological characteristics of lung during respiration. As examples, this report shows the method of exchanging mechanical energy to chemical energy in a comparison of lung ventilatory work between smokers and non-smokers. This report discusses the relationship between chemical energy and ATP in the blood of pneumoconiosis patients.

Non-dipper phenomenon in essential hypertension is related to blunted nocturnal rise and fall of sympatho-vagal nervous activity and progress in retinopathy

Although the relation between the blunted nocturnal decline in blood pressure and target organ damages is well established, the mechanism underlying these results has not been clarified. We investigated the relationship among heart rate variability, nocturnal change in blood pressure and the severity of cardiac and extracardiac target organ damages caused by essential hypertension. We studied 52 Japanese inpatients with essential hypertension (24 men and 28 women; mean age, 49+/-3 years). After a stabilization period of 1 week, ambulatory blood pressure monitoring (ABPM) and 24-h ECG monitoring were performed and analyzed. The non-dipper subjects were defined as those whose nocturnal decrease of mean BP was < 10% of daytime blood pressure (BP). The sex, age, body mass index. duration of hypertension, and 24-h BP were similar in dipper (n = 34) and non-dipper (n = 18) patients. The left ventricular mass index (LVMI) was significantly higher and the degree of hypertensive retinopathy was significantly worse in the non-dipper patients than that of the dipper patients. In the non-dipper patients, indexes of time-domain analysis such as the sum of differences between adjacent RR intervals (NNDrms), the number of pairs of adjacent RR intervals differing by more than 50 ms in the entire recording (RR 50) were significantly lower than that of the dipper patients. Additionally, as for spectral analysis, daytime low frequency/high frequency (LF/HF) was higher and nighttime high frequency (HF) was lower than that of the dipper patients. Independent predictors were the 24-h mean blood pressure (MBP) for left ventricular hypertrophy (LVH), nighttime systric BP (SBP) for progress in retinopathy and duration of hypertension for proteinuria. In conclusion, decrease in parasympathetic nervous function and increase in sympathetic nervous function may contribute to occurrence of non-dipper phenomenon, as well as progress in retinopathy.

Coronary atherosclerosis and oxidative stress as reflected by autoantibodies against oxidized low-density lipoprotein and oxysterols

Clinical studies and animal experiments have demonstrated that oxidized low-density lipoprotein (oxLDL) and oxysterols play important roles in atherogenesis. OxLDL is immunogenic, and autoantibodies (Ab) against oxLDL are detectable in serum. We investigated the relevance of oxysterols and Ab against-oxLDL to coronary artery disease (CAD) in 183 patients undergoing coronary angiography. Patient groups included angiographically normal subjects (< 75% stenosis), others with spasm (> 75% narrowing in response to acetylcholine), and some others with fixed stenosis (> 75%). The group with stenosis was subdivided into patients with stable and unstable angina. Serum concentrations of autoantibodies and 25-, 27-, and 7-beta-hydroxycholesterols were significantly higher in the stenotic group than in the normal group (P < 0.01, P < 0.05, P < 0.05, and P < 0.05, respectively). Antibodies, but not oxysterol concentrations, were significantly greater in subjects with unstable than with stable angina (P < 0.01). We conclude that anti-oxLDL antibody and oxysterol concentrations are associated with coronary artery stenosis, and that oxidative stress may be greatly increased in unstable angina.

Human skin-derived mast cells can proliferate while retaining their characteristic functional and protease phenotypes

Human mast cells in adult tissues have been thought to have limited, if any, proliferative potential. The current study examined mast cells obtained from adult skin and cultured in serum-free medium with recombinant human stem cell factor. During the first 4 weeks of culture, the percentages of mast cells increased from 10 to almost 100. After 8 weeks, a 150-fold increase in the number of mast cells was observed. When freshly dispersed mast cells were individually sorted onto human fibroblast monolayers and cultured for 3 weeks, one or more mast cells were detected in about two thirds of the wells, and in about two thirds of these wells the surviving mast cells showed evidence of proliferation, indicating most mast cells in skin can proliferate. Such mast cells all expressed high surface levels of Kit and Fc epsilon RI, each of which were functional, indicating IgE was not required for Fc epsilon RI expression on mast cells. Such mast cells also retained the MC(TC) protease phenotype of mast cells that normally reside in the dermis. After 4 to 8 weeks of culture these mast cells degranulated in response to substance P and compound 48/80, characteristics of skin-derived mast cells that persist outside of the cutaneous microenvironment. (Blood. 2001;97:2045-2052)

Disialoganglioside GD3 is selectively expressed by developing and mature human mast cells

BACKGROUND

Disialoganglioside GD3 is expressed on the surface of selected cell types. Anti-GD3 mAb administered to human subjects with malignant melanoma produces signs and symptoms of immediate hypersensitivity reactions.

OBJECTIVE

The expression of GD3 by human mast cells was assessed during mast cell development in vitro and in samples of lung and skin.

METHODS

GD3 on tissue- and in vitro-derived mast cells was analyzed after double labeling of cells for tryptase (G3 mAb) or Kit (YB5.B8 mAb) and GD3 (R24 mAb). Glycolipids in extracts of fetal liver-derived mast cells were examined by using high-performance thin-layer chromatography.

RESULTS

Flow cytometry showed that the percentage of GD3+ cells increased in parallel to Kit+ cells during the recombinant human stem cell factor-dependent development of fetal liver-derived mast cells. Double-labeling experiments showed that GD3+ cells were also surface Kit+ and granule tryptase positive, identifying them as mast cells in preparations of lung-, skin-, fetal liver-, and cord blood-derived cells. The major acidic glycolipid detected was NeuAcalpha2-8NeuAcalpha2-3Galbeta1-4Glcbeta1-1'Cer (GD3). Among peripheral blood leukocytes, only basophils and about 10% of the T cells were labeled with anti-GD3 mAb. Anti-GD3 mAb-conjugated magnetic beads were used to purify mast cells to greater than 90% purity from dispersed skin cells enriched to approximately 12% purity by means of density-dependent sedimentation but were less proficient for dispersed human lung mast cells, most likely because of other cell types that express GD3.

CONCLUSION

GD3 is expressed on the surface of developing human mast cells in parallel to tryptase in secretory granules and, like Kit, can serve as a target for their enrichment by immunoaffinity techniques.

Abnormal Ca2+ handling and increased Mg2+ permeability in platelets of hypertensive rats

In order to test the hypothesis that intracellular Na+ accumulation and cellular Mg2+ deficiency may be involved in the abnormalities in Ca2+ handling and reactivity in spontaneously hypertensive rats (SHR) platelets, the metabolism of Na+, Ca2+ and Mg2+ was determined in fluorescent dye loaded platelets from 15 SHR and 15 Wistar-Kyoto rats (WKY) at 12 weeks of age. Mg2+ leak was estimated as the Mg2+ influx induced by an increase in extracellular [Mg2+] (from 1 to 5 mmol/l) and Mg2+/Na+ exchange activity was estimated as the Mg2+ influx induced by a decrease in extracellular [Na+] (from 140 to 50 mmol/l). Cellular metabolism of the fluorescent dye was similar in the two groups. Mean platelet [Ca2+]i was significantly increased under basal and thrombin (0.1 U/ml)-stimulated conditions in SHR compared to WKY, both in the presence and absence of extracellular Ca2+. Mean Ca2+ discharge capacity was similar between the two groups. There was no difference in mean [Na+]i between the two groups. Basal [Mg2+]i was also increased in SHR platelets. Mg2+ leak was higher in SHR than in WKY, while Mg2+/Na+ exchange activity was similar in the two groups. There was no difference in serum Mg2+ concentration between SHR and WKY. These data suggest that abnormal Ca2+ handling is accompanied by elevation in [Mg2+]i via increased permeability of platelet cell membranes to Mg2+ in SHR without any alteration in [Na+]i, and do not support the Mg2+ deficiency hypothesis in genetically hypertensive rats.

Mechanism of anti-tumor effect of combination of bleomycin and shock waves

We have previously reported marked enhancement of the cytocidal effect of bleomycin (BLM) on cancer cell suspensions in vitro by the combination with shock waves. In this study, we evaluated the synergistic effects on cancer cell proliferation and apoptosis in solid tumors. A spherical piezo-ceramic element was used as the shock wave source, with a pressure peak of 40 MPa. A human colon cancer cell line, SW480 was implanted onto the back of nude mice. Two thousand shock waves were administered to the tumor immediately following an intravenous injection of BLM at a dose of one-tenth of the LD(50). The tumor was extirpated at 3, 6, 12, 24, 72 h and 1 week following shock exposure. Cell proliferation and apoptosis were detected by Ki-67 using antibody MIB-1 and by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labeling (TUNEL) method. The lowest percentage (35.7%) of Ki-67-positive cells appeared 24 h following the treatment. The maximum apoptotic index was detected within 6 h following the treatment. Moreover, numerous large cells with enlarged nuclei were detected histologically. These results suggest that shock waves may enhance chemotherapeutic effects by increasing apoptosis and decreasing cell proliferation in the tumor tissue.

[Results of a questionnaire survey about "standardization" of connection methods in Laboratory Automation System or Laboratory Information System by the National University Hospital Clinical Laboratory Divisions]

"Standardization" is very important in the field of clinical laboratory medicine. Enzyme reference materials(ERM) and standard plasma proteins(CRM470) have already been developed. Reference methods for some clinical chemical tests have also been developed. We are studying "standardization" of electric communication methods between computers and automatic analyzers in Laboratory Automation System(LAS) or Laboratory Information System(LIS). We present the results of a questionnaire survey of 73 LAS or LIS making Companies in this paper. Although "standardization" of electric communications or local area network in LAS or LIS has been done in only 22 companies(34.9%), we are planning more functional standard electric communication methods such as Health Level 7(HL7) or American Society for Testing and Materials(ASTM).

[Development of a case of Mycobacterium avium complex disease from right pleural effusion]

Moist pleurisy in patients with Mycobacterium avium Complex (MAC) is rarer than tuberculosis. We encountered an extremely rare case of MAC disease in a 75-year-old man who initially had only right pleural effusion. Gaffky VII was detected in the pleural effusion, and Mycobacterium avium was identified by culture and PCR. Although administration of antitubercular agents (RFP, INH, EB, and SM) + CAM and thoracic lavage were repeated, the Gaffky persisted strongly. Accordingly, pulmonary decortication and filling of the cavity with an omental flap were performed as surgical treatments. However, fistulas were formed between the remaining empyema cavity and the surgical wounds. Fenestration was also carried out. Postoperatively, centriacinar abnormalities appeared on computed tomography (CT). It has been reported that MAC disease begins with centriacinar abnormalities and the incidence of the lymphatic developmental pattern was low. Tuberculosis (the idiopathic pleuritis type) is considered to be caused this pattern from the primary infection focus. Therefore, the onset of unilateral effusion is extremely rare in patient with MAC disease, suggesting that the lymphatic developmental pattern occurs less frequently in patients with MAC disease. Furthermore, in this case, we speculated that centriacinar abnormalities were the MAC infection foci and could be detected by CT due to surgical invasion.

[Evaluation of vascular endothelial function]

Endothelial function was evaluated in renal and forearm vessels from patients with essential hypertension. First, the increase in renal blood flow evaluated by the clearance of para-aminohippurate, serum c-GMP and urinary NOx during L-arginine infusion was significantly attenuated in essential hypertension. This attenuated endothelium-dependent vasodilation was improved by angiotensin converting enzyme inhibitor, but unchanged by calcium antagonist. Second, the increase in forearm blood flow evaluated by plethysmography during acetylcholine infusion or reactive hyperemia was attenuated in essential hypertension. This attenuation was abolished by NO synthesis inhibitor. Forearm endothelial function was improved by angiotensin converting enzyme inhibitor, daily aerobic exercise and body weight reduction by low calorie diet. In conclusion, endothelium-dependent vasodilation was attenuated in renal and forearm vasculature of essential hypertensives via reduction of NO synthesis. This attenuation can be improved by several treatments.

An improved procedure for the development of human mast cells from dispersed fetal liver cells in serum-free culture medium

The in vitro development of human mast cells from fetal liver cells with recombinant human stem cell factor in serum-containing RPMI was compared to that in AIM-V media with and without serum. Compared to serum-containing media, AIM-V medium caused mast cells to develop earlier and in greater numbers. By 2 weeks, about 60% of cells in serum-free AIM-V medium were phenotypic mast cells, approximately 2 times the percentages in serum-containing media. By 6 weeks the percentages of mast cells were > or =80% under all conditions, but the number of mast cells was 3-4-fold greater in serum-free AIM-V medium than in serum-supplemented media. Mast cells obtained in serum-free AIM-V medium exhibited rounded nuclei, like tissue-derived mast cells; mast cells obtained in serum-supplemented media had segmented nuclei. By 10-12 weeks of culture about 40% of the AIM-V-derived cells showed strong chymase immunocytochemical staining, a pattern observed for only 14% of the cells in serum-containing media. AIM-V medium is a suitable medium for the development of human mast cells in vitro, and permits an earlier, more selective and greater expansion of mast cells than serum-containing media.

Type 1A dopamine receptor expression in the heart is not altered in spontaneously hypertensive rats

We have recently demonstrated that type 1A dopamine (D1A) receptor is expressed in the rat heart, but its function still remains unknown. In the present study, we investigated possible changes in the expression level and the distribution of the cardiac D1A receptor in the development of left ventricular hypertrophy in spontaneously hypertensive rats/Izumo strain (SHR/Izm) at the ages of 4, 8, and 20 weeks. We examined D1A receptor protein distribution by immunohistochemistry and gene expression by competitive polymerase chain reaction (competitive PCR). In SHR/Izm, compared with the age-matched Wistar Kyoto rats/Izmo strain (WKY/Izm), blood pressure and heart/body weight ratio were significantly increased at 8 and 20 weeks. By immunohistochemistry, the D1A receptor was localized in cardiomyocytes and vascular smooth muscle cells of coronary arteries, but not in interstitial fibrotic tissue. D1A receptor distribution was not changed either by the strain or the age. Competitive PCR analysis showed that the D1A receptor mRNA level was significantly higher at 4 weeks than at 8 and 20 weeks in both strains of rats and that there was no significant difference in D1A receptor mRNA between SHR/Izm and WKY/Izm at any age (43.2 +/- 10.4 attomol x 10(-3)/L v 43.1 +/- 11.2 attomol x 10(-3)/L at 4 weeks, P = not significant, 3.9 +/- 0.9 attomol x 10(-3)/L v 4.0 +/- 1.3 attomol x 10(-3)/L at 8 weeks, P = not significant, 3.0 +/- 1.2 attomol x 10(-3)/L v 1.9 +/- 1.6 attomol x 10(-3)/L at 20 weeks, P = not significant). These results do not support the hypothesis that changes in D1A receptor expression are associated with the development of left ventricular hypertrophy in SHR.

Type 2 angiotensin II receptor is downregulated in cardiomyocytes of patients with heart failure

BACKGROUND

The human heart expresses type 2 angiotensin (AT(2)) receptor, but the function is poorly defined.

METHODS

In the present study, we investigated (1) the cellular localization of the AT(2) receptor and (2) the relationship between the AT(2) receptor protein expression and the cardiac function of patients with ischemic heart disease. The receptor localization was assessed by immunohistochemistry and the protein expression was quantified by Western blotting in atrial tissues freshly obtained from 22 patients undergoing coronary artery bypass graft surgery (63.0+/-11.0 years old; male ratio, 85%). Prior to the surgery, blood was drawn for determination of atrial-natriuretic hormone level and the left ventricular function was assessed by ultrasound cardiography.

RESULTS

The results of immunohistochemistry showed that the AT(2) receptor was localized to cardiomyocytes and was not present in fibroblasts, vascular smooth muscles, or vascular endothelium. Atrial tissues showed various degrees of structural remodeling, but the localization of the AT(2) receptor was not altered in any tissue sections. The amount of the AT(2) receptor was negatively correlated with end-diastolic left ventricular diastolic dimension (r=-0.56, P<0.01), calculated left ventricular mass index (r=-0.51, P<0.02) and the plasma atrial natriuretic peptide (ANP) concentration (r=-0. 62, P<0.01) and positively correlated with left ventricular ejection fraction (r=0.48, P<0.05).

CONCLUSIONS

(1) The AT(2) receptor is localized to cardiomyocytes independently of the cardiac function. (2) Left ventricular dysfunction is associated with decreased expression of myocardial AT(2) receptor protein.

Anti-K-ras ribozyme induces growth inhibition and increased chemosensitivity in human colon cancer cells

Colon cancer is one of the carcinomas that is resistant to a variety of therapies. To develop a new therapy by regulating the activated K-ras gene in colon cancers, we prepared synthetic DNA encoding the ribozyme (catalytic RNA), and inserted it into an expression vector (LNCX) originated from a retrovirus. Transfection of the vector into SW620 human colon cancer cells brought about significant suppression of K-ras mRNA synthesis and inhibition of the cell growth. Studies in athymic mice, in which K-ras ribozyme-introduced SW620 cells were transplanted, also revealed a marked reduction of tumor growth in vivo. Furthermore, the ribozyme-introduced tumors became more sensitive to treatment with anti-cancer drugs such as cisplatin, adriamycin, 5-fluorouracil, vincristine, and etoposide. These data suggest that the possible efficacy of anti-K-ras ribozyme increases the chemosensitivity of human colon cancers as well as the inhibitory effect on the growth of human colon cancers.

Expression and localization of angiotensin subtype receptor proteins in the hypertensive rat heart

The cellular localization of the AT(2) receptor and the regulation of its expression in hypertrophied left ventricle are not well known. We compared the expression of the cardiac AT(1) and AT(2) receptor in spontaneously hypertensive rats/Izumo strain (SHR/Izm) and Wistar Kyoto rats/Izumo strain (WKY/Izm), ages 4, 12, and 20 wk, by means of immunohistochemistry and Western blot analysis. In SHR/Izm, compared with WKY/Izm, blood pressure (161 +/- 2 vs. 120 +/- 2 mmHg at 12 wk, P </= 0.01, and 199 +/- 3 vs. 123 +/- 3 mmHg at 20 wk, P </= 0.01) and heart-to-body weight ratio (3.76 +/- 0.07 vs. 3.06 +/- 0.06 mg/g at 12 wk, P </= 0.01, and 3.90 +/- 0.08 vs. 3.01 +/- 0.12 mg/g at 20 wk, P </= 0.01) were significantly elevated. There was no difference in these values between the two strains at 4 wk of age. Histologically, 20-wk-old SHR/Izm demonstrated myocardial hypertrophy, a thickening of the smooth muscle layer of the intracardiac arteries, and perivascular fibrosis. By immunohistochemistry, the AT(2) receptor was localized to cardiomyocytes and vascular endothelial cells, but not in the vascular smooth muscle cells. No major AT(2) receptor signal was observed in perivascular fibrosis at any age in either strain of rats. No difference was detected in this localization between the two strains. By Western blotting, a single 44-kDa band for the AT(2) receptor and a single 60-kDa band for the AT(1) receptor were detected in ventricles from both strains of rats at all ages. Densitometric analysis demonstrated that the AT(2) receptor 44-kDa band was decreased by 20% at 12 wk and 32% at 20 wk (P < 0.01) in SHR/Izm compared with WKY/Izm. The intensity of the AT(1) receptor 60-kDa band was increased by 57% in 20-wk-old SHR/Izm compared with WKY/Izm (P < 0.05). There was no significant difference in the intensity of the 44- or 60-kDa bands in 4-wk-old animals of either strain. We demonstrated a decrease in the AT(2) receptor and an increase in the AT(1) receptor protein with no change in their localizations in hypertrophied left ventricular myocytes of SHR/Izm.

Abnormal magnesium status in patients with cardiovascular diseases

To investigate magnesium status in patients with cardiovascular diseases and in those presenting high factors for these diseases, we measured the concentrations of serum total Mg, serum ionized Mg and intra-erythrocyte Mg. Mg is an important cofactor for many enzymes, especially those involved in phosphate transfer reactions. Mg deficiency has been shown to be associated with fatal cardiovascular diseases, as well as with risk factors for these diseases. Only measurement of the serum concentration of total Mg is routinely available, but ionized Mg is the physiologically active component. Furthermore, most of the body's Mg is present in the intracellular space. Subjects included patients with ischaemic heart disease (n=80), cardiac arrhythmia (n=60), diabetes mellitus (n=36), essential hypertension (n=194) and hypercholesterolaemia (n=60). The same measurements were made in healthy controls (30 men and 26 women; mean age 58+/-11 years). The serum ionized Mg concentration was measured with a selective ion electrode. The intra-erythrocyte Mg concentration was measured by atomic absorption. No gender difference was found for any Mg parameter, nor was age related to any Mg parameter. The serum albumin concentration was positively correlated only with the serum total Mg concentration. Although the serum total Mg concentration was similar in all groups, patients with diabetes mellitus and arrhythmia had lower serum levels of ionized Mg. Patients with essential hypertension exhibited higher intra-erythrocyte Mg concentrations than the healthy controls. Thus the measurement of serum total Mg concentration may obscure the presence of extracellular Mg deficiency in patients with arrhythmia and diabetes mellitus. Furthermore, the intracellular accumulation of Mg does not support the hypothesis of Mg deficiency in patients with essential hypertension.

[Expired nitric oxide concentration derived from nasal cavity and that derived from airway and lung in Japanese cedar pollinosis]

AIM

Japanese cedar pollinosis (Type I allergy to Japanese cedar pollen) shows a high incidence in spring in Japan, demonstrating symptoms such as pituita, rhinostenosis, lacrimation and sometimes pharyngeal pain. The following study investigated whether expired nitric oxide (NO) concentration is increased in Japanese cedar pollinosis, and whether expired NO concentration can be used to discriminate from cold syndrome which symptoms are similar to Japanese cedar pollinosis.

SUBJECTS AND METHODS

In 20 healthy subjects, 20 patients with Japanese cedar pollinosis and 20 patients with cold syndrome, expired NO concentrations derived from nasal cavity and those derived from airway and lung were measured. Expired NO concentrations derived from nasal cavity and those derived from airway and lung were compared among the groups.

RESULTS

In patients with Japanese cedar pollinosis expired NO concentrations derived from nasal cavity and those derived from airway and lung markedly increased. In patients with cold syndrome there were no significant increases in these concentrations.

DISCUSSION

It is considered that expired NO concentration is useful for discriminating Japanese cedar pollinosis from cold syndrome. It seems interesting that not only expired NO concentrations derived from nasal cavity but also those derived from airway and lung were clevated. Generalized airway inflammation may be present, even without clinical asthma, in patients with Japanese cedar pollinosis.

[The future of clinical laboratory database management system]

To assess the present status of the clinical laboratory database management system, the difference between the Clinical Laboratory Information System and Clinical Laboratory System was explained in this study. Although three kinds of database management systems (DBMS) were shown including the relational model, tree model and network model, the relational model was found to be the best DBMS for the clinical laboratory database based on our experience and developments of some clinical laboratory expert systems. As a future clinical laboratory database management system, the IC card system connected to an automatic chemical analyzer was proposed for personal health data management and a microscope/video system was proposed for dynamic data management of leukocytes or bacteria.

[Significance of area under the flow volume curve--useful index of bronchial asthma]

Some studies have reported that area under the flow volume curve (AUFVC) can be an index of pulmonary function. However, the significance of AUFVC remains to be clarified. We have clarified that AUFVC reflects the momentum of expired air. Size of flow volume curve (= AUFVC) has been commonly recognized to be changeable visually in patients with asthma. To clarify whether size of flow volume curve (= AUFVC) is a useful index of the course of bronchial asthma, we compared the rate of improvement forced expiratory volume in 1 second (FEV1.0), peak expiratory flow rate (PEFR) or forced vital capacity (FVC) to the rate of improvement in AUFVC after admission in 20 patients with bronchial asthma. The rate of improvement in AUFVC positively correlated with the rate of improvement in FEV1.0, PEFR or FVC. AUFVC demonstrated more marked improvement than other indices. Since AUFVC reflects the momentum of expired air, bronchial asthma's patients could understand visually that the momentum of expired air decreased due to airway stenosis by presenting flow volume curve. Therefore, visual size of flow volume curve helped patients with asthma to understand the condition of asthma. Size of flow volume curve (AUFVC) may be useful index of the course of bronchial asthma.

[Magnesium (Mg) status in patients with cardiovascular diseases]

Mg is the fourth most abundant total cation in the human body and the second most abundant intracellular cation. Moreover, Mg is an important cofactor for many enzymes especially those involved in phosphate transfer reactions. Mg is therefore essential in the regulation of the metabolism of other ions and cellular functions. Mg deficiency has been shown to be associated with fatal cardiovascular diseases such as cardiac arrhythmias and coronary heart disease, as well as with risk factors for these diseases, such as hypertension, and diabetes mellitus. Clinical evaluation of Mg status has been limited by the lack of suitable technology for measuring this cation. Although the measurement of serum total Mg is routinely available, ionized Mg is physiologically active. Furthermore, most of the body's Mg is present in the intracellular space. Our findings showed that serum total Mg was similar in all groups, but patients with arrhythmias and diabetes mellitus revealed lower levels of serum ionized Mg. On the other hand, patients with essential hypertension exhibited higher intraerythrocyte Mg concentrations than healthy controls. The measurement of serum total Mg may obscure the diagnosis of an abnormality in Mg metabolism in patients with arrhythmias and diabetes mellitus. Furthermore, the intracellular accumulation of Mg does not support the hypothesis of Mg deficiency in patients with essential hypertension.

[The present and future of the pulmonary function tests. The relationship between respiratory and non-respiratory function]

Pulmonary function is classified as respiratory and non-respiratory function. Respiratory pulmonary function involves exchange of O2 and CO2 gas at alveolar units in the lung and non-respiratory pulmonary function concerns metabolism of enzymes, hormones, surfactants vaso-active substances and immunological factors in the lung. The purpose of this study was to examine the relationship between respiratory and non-respiratory function using our newly developed expired NO gas continuous analytic method and the calculation method of ventilatory energy of the lung. Furthermore, we analyzed the relationship between arterial blood O2 pressure (PaO2) and mitochondrial function.

Effect of L-arginine infusion on systemic and renal hemodynamics in hypertensive patients

This study was designed to compare the renal endothelial function in patients with essential hypertension and normal renal function with that in hypertensive patients with renal insufficiency. We studied the effects of L-arginine (500 mg/kg intravenously over 30 min) on renal hemodynamics in 30 normotensive control subjects, 32 patients with mild to moderate essential hypertension who had normal renal function, and seven hypertensive patients with renal insufficiency who had a serum creatinine concentration >2.0 mg/mL and a glomerular filtration rate <50 mL/min/1.48 m2. L-Arginine infusion similarly reduced the mean blood pressure between the three groups (normotensive: -9.7% +/- 0.7%, hypertensives with normal renal function: -10.2% +/- 0.8%, and hypertensives with renal insufficiency: -8.2% +/- 1.3%). The L-arginine-induced decrease in renal vascular resistance was smaller in essential hypertensive patients than in normotensive subjects (-11.0% +/- 2.2 v -19.8% +/- 2.1%, P <.05). However, L-arginine had no effect on the renal vascular resistance in hypertensive patients with renal insufficiency (1.6% +/- 4.8%). Urine nitrite/nitrate levels in response to L-arginine significantly increased in the three groups in the following order: patients with renal insufficiency (47% +/- 15%), essential hypertensive patients (87% +/- 10%), and normotensive subjects (129% +/- 12%). The glomerular filtration rate was unaffected by L-arginine in normotensive and essential hypertensive patients (3.1% +/- 2.4% and 4.2% +/- 2.5%), but significantly decreased in hypertensive patients with renal insufficiency (-13.7% +/- 6.1%). These findings suggest that the ability of the L-arginine-nitric oxide-cGMP pathway to relax the renal vascular tone may be impaired in essential hypertensive patients and more markedly blunted in hypertensive patients with renal insufficiency, in parallel with increasing serum creatinine concentrations.

[A case of cervical-mediastinal lymph node tuberculosis progressed to pulmonary lesion through a bronchial fistula]

The patient was a 25-year-old man who had been admitted to a local hospital due to fever and trachelophyma. Tubercle bacillus was detected in pus culture obtained by biopsy of the trachelophyma, but not in sputum culture. Because combined therapy with 3 antituberculous drugs (RFP, INH and SM) failed to reduce the fever or drainage from the biopsy region, the patient was transferred to our hospital. Chest X-ray films taken on admission revealed dilatation of the superior mediastinal shadow; chest CT images revealed cervical and mediastinal lymphadenopathy and an anterior mediastinal abscess, but no pulmonary lesion. About 2 months after admission, cough developed and Gaffky type 2 was detected in the patients sputum. Bronchoscopy and bronchography revealed a bronchomediastinal fistula. Forty days after the onset of cough, reticulogranular shadows were observed in the right upper lobe on chest X-ray films, and a diffuse centrilobular lesion was observed in the right upper lobe on chest CT images. From these clinical observations, the patient was given a diagnosis of cervical-mediastinal lymph node tuberculosis, which had progressed to pulmonary lesion through a bronchial fistula due to lymphadenitis.

Cloning and characterization of a novel zinc finger protein that associates with nuclear matrix

We have recently reported that the nuclei of B16 melanoma cells are intensely stained with anti-rat vitronectin (Vn) antibody, which reacts with both mouse and rat Vn. In the present study, we characterized the protein immunoreactive with the antibody using NIH3T3 cells, whose nuclei were also stained with the antibody. Western blot analysis showed that a protein with an approximate molecular weight of 75 kDa (p75), which was distinct from Vn, existed in the nuclear fraction, and, more specifically, in the nuclear matrix fraction, of NIH3T3 cells. Screening of an NIH3T3 cDNA library resulted in the isolation of a nearly full-length cDNA clone encoding p75. A database search revealed that the cDNA represents a novel gene. The deduced amino acid sequence showed that the protein is 580 amino acids long and contains two C2H2-type zinc finger motifs and glutamic acid-rich domains in the C-terminal region. When a fusion protein of green fluorescence protein and p75 was expressed in NIH3T3 cells, fluorescence was preferentially observed in the nuclei, demonstrating that the protein has a nuclear localization signal. The p75 protein, termed ZAN75, exhibited DNA-binding activity in a zinc-dependent manner. Southern blot analysis demonstrated that the ZAN75 gene exists in a single copy in the mouse genome and that a closely related gene is also present in chicken, rat, and human. Northern blot analysis showed that the ZAN75 gene is ubiquitously expressed in adult mouse tissues. In the cell cycle of NIH3T3 cells, expression was low in the G0/G1 phase, increased during the G1 phase, and persisted during the S and G2/M phases, suggesting that ZAN75 plays a role in regulating cell growth.

[A mild case of acute eosinophilic pneumonia]

We encountered a mild case of acute eosinophilic pneumonia in a 24-year-old man who developed symptoms once he started smoking. Bronchoalveolar lavage revealed eosinophilia. Chest computed tomography revealed a small amount of bilateral pleural effusion and multicentric panacinar shadows with peripheral ground-glass opacities. During the clinical course, the patient suffered only cough and fever, which subsided in 13 days without the administration of steroids. Although the clinical course in this case resembled that of simple pulmonary eosinophilia, we diagnosed it as a mild case of acute eosinophilic pneumonia because pleural effusion rarely accompanies simple pulmonary eosinophilia, symptoms developed when the patient began smoking, and interstitial involvement was suggested by bilateral effusion and ground-glass opacity. We look forward to the establishment of the disease concept of acute eosinophilic pneumonia, including mild cases, and a classification system for eosinophilic lung diseases, including acute eosinophilic pneumonia.

Angiotensin-converting enzyme inhibition, but not calcium antagonism, improves a response of the renal vasculature to L-arginine in patients with essential hypertension

Endothelial function has been shown to be impaired in patients with essential hypertension. The purpose of the present study was to determine whether antihypertensive drug therapy improves impaired endothelium-dependent renal vasorelaxation in essential hypertensive patients without atherosclerosis. We evaluated the effects of intravenous infusion of L-arginine (500 mg/kg given over 30 minutes) on systemic and renal hemodynamics in 27 patients with mild to moderate essential hypertension who were randomly assigned to treatment with either the angiotensin-converting enzyme inhibitor imidapril or the calcium antagonist amlodipine for 12 weeks in a double-blind fashion. After the 12 weeks, the decrease in blood pressure was similar in the imidapril (n=14) and amlodipine (n=13) groups. The increase in renal plasma flow was also similar in both groups. L-Arginine-induced renovascular relaxation was increased by imidapril (renal plasma flow, 9.6+/-5.1% to 14.4+/-7.4%; renal vascular resistance, -10.4+/-8.1% to -16.7+/-9.2%, P<0.05, respectively) but not by amlodipine. Urinary excretion of nitrite/nitrate in response to L-arginine was significantly increased by imidapril (90+/-29% to 134+/-63%, P<0.05) but remained unchanged by amlodipine. These findings suggest that angiotensin-converting enzyme inhibition improves the impaired endothelium-dependent renovascular relaxation in patients with essential hypertension due to the increase in nitric oxide production and that the reduction in blood pressure with a calcium antagonist does not play a major role in the potentiation of L-arginine/nitric oxide-mediated effects.

Effect of 17beta-estradiol on inhibition of platelet aggregation in vitro is mediated by an increase in NO synthesis

The low prevalence of coronary heart disease in premenopausal women and its increase after menopause are well established. Although estrogen is thought to play a role in protecting the vasculature, the mechanism has not been fully clarified. The contribution of platelets to atherosclerotic cardiovascular diseases is well recognized. The present study focused on the still-controversial effect of estrogen on platelet function. We investigated the in vitro effects of estrogen on human platelets, including their aggregation, Ca2+ metabolism, the synthesis of cyclic nucleotides, and NO (nitrite/nitrate) synthesis after stimulation with thrombin or ADP. Pretreatment of platelets with 17beta-estradiol reduced the platelet aggregation induced by thrombin or ADP, whereas 17alpha-estradiol had no effect. 17Beta-estradiol accelerated the recovery of [Ca2+]i after the agonist-induced peak and reduced the area under the curve of accumulated platelet [Ca2+]i but did not alter the baseline [Ca2+]i, Ca2+ influx induced by thrombin or ADP, the release of Ca2+ from internal stores, or the size of internal Ca2+ stores. Pretreatment of platelets with 17beta-estradiol had no effect on the intracellular concentration of cAMP but increased that of cGMP in agonist-stimulated platelets. Additionally, 17beta-estradiol increased the platelet concentration of nitrite/nitrate in a dose-dependent manner. These effects of 17beta-estradiol on platelet aggregation, Ca2+ metabolism, and NO synthesis were abolished by exposure to N(G)-monomethyl-L-arginine, an NO synthesis inhibitor. These results suggest that 17beta-estradiol plays an important role in inhibiting platelet aggregation by promoting Ca2+ extrusion or reuptake activity that is dependent on the production of cGMP by increasing NO synthesis.

DD genotype of the angiotensin I-converting enzyme gene is a risk factor for early onset of essential hypertension in Japanese patients

Although angiotensin-converting enzyme (ACE) plays an important role in blood pressure regulation, no relationship between the insertion/deletion (I/D) polymorphism of the ACE gene and essential hypertension has been observed. However, as the pathogenesis and genetic background of essential hypertension are heterogeneous, we investigated whether the ACE gene is a marker of subgroups of patients with essential hypertension. A group of 178 patients with essential hypertension (90 men/88 women; 53 +/- 13 years of age, mean age +/- SD ) and 101 normotensive control subjects (54 men/47 women; 51 +/- 14 years of age, mean age +/- SD ) were included in the study. The allele frequencies of the two groups were similar. There were no differences in age, blood pressure, retinopathy grade, presence of proteinuria, or resting plasma renin activity (PRA) among the hypertensive patients with the II, ID, and DD genotypes. However, the age of onset of hypertension of patients with the DD genotype was lower (p < 20.05) and their left ventricular mass index was higher (p < 2 0.05) than those in patients with the non-DD genotype. These data suggest that the I/D polymorphism of the ACE gene is associated with an early onset of hypertension and left ventricular hypertrophy in Japanese patients with essential hypertension.

[Measurement of expired nitric oxide concentration]

Much interest has been focused on standardization of measurement of expired nitric oxide (NO) concentration. The aim of this study was establish a simple measurement of expired NO concentration.

SUBJECTS AND METHODS

This study included 5 healthy male adults. To clarify whether NO is excreted in expired air constantly, its concentrations were measured while changing the flow rate. To examine the influence of NO derived from the nasal cavity, we compared expired No concentrations sampled from the month with those sampled from the endotracheal tube inserted to the trachea at a constant flow rate serially.

RESULTS

Expired NO concentrations decreased in inverse with the flow rate. No may be serially excreted in expired air. When serial changes of expired No concentrations sampled from the mouth were examined, its NO concentration initially reached a peak, then showed a plateau. Serial changes of those sampled from the endotracheal tube showed only a plateau. Plateau levels were not different between the two kinds. Therefore the peak values may have been influenced by NO derived from the nose that fell in the trachea by inspiration. Plateau values appeared to represent airway and lung-derived NO.

CONCLUSIONS

A simple measurement of expired NO concentration should be sampled from the mouth at a constant flow rate serially. Evaluating plateau values is appropriate for expired NO concentration.

Activation of platelets in bronchial asthma

STUDY OBJECTIVES

To investigate whether platelets are activated in asthmatics with increased release of preformed mediators and to investigate the influence of oral administration of theophylline on them.

DESIGN

Comparison of the intracellular free calcium concentration ([Ca2+]i) in platelets as an indicator of platelet activation, CD62P expression on platelets, and the chemokine regulated upon activation in normal T cells expressed and presumably secreted (RANTES) level in platelet-rich buffer supernatants between asthmatics and normal subjects.

SETTING

The respiratory outpatient clinics, Hiroshima University, Japan.

PARTICIPANTS

Twenty-five normal volunteers, 19 asthmatics taking no oral drugs associated with asthma treatment (group A), and 18 asthmatics taking oral theophylline (group B).

MEASUREMENTS AND RESULTS

While the resting [Ca2+]is in platelets were similar among the three groups, the [Ca2+]is in group A were significantly higher than those in normal subjects (p<0.05) and group B (p<0.01) after thrombin or 9,11-epithia-11,12-methano-thromboxane A2 (STA2) stimulation in the absence of external Ca2+. The CD62P expression level and RANTES level in group A after STA2 stimulation were significantly higher than those in normal subjects and group B (p<0.05).

CONCLUSIONS

We conclude that agonist-mediated activation of platelets is augmented in asthmatics resulting in enhanced release of chemokine such as RANTES, which could be suppressed by oral administration of theophylline.

Increased cytosolic free Mg2+ and Ca2+ in platelets of patients with vasospastic angina

This study was designed to test the hypothesis that the cellular metabolism of Ca2+ and Mg2+, which is important in platelet function, is abnormal in the platelets of patients with vasospastic angina. Cytosolic free Mg2+ concentration ([Mg2+]i) and Ca2+ handling were determined in the platelets of 24 patients with vasospastic angina and 24 control subjects by use of mag-fura 2 and fura 2. Platelet aggregation was also examined. Basal [Mg2+]i and cytosolic free Ca2+ concentration ([Ca2+]i) in platelets were significantly higher in patients with vasospastic angina than in control subjects. The amplitude of the [Ca2+]i transient induced by thrombin (0.03-1.0 U/ml) was significantly increased in the presence, but not in the absence, of extracellular Ca2+ in patients with vasospastic angina, as compared with controls. Therefore, the influx of Ca2+ across the plasma membrane may be accelerated in vasospastic angina. Thrombin (0.1-1.0 U/ml)-induced maximum aggregation response was significantly greater in patients with vasospastic angina than in controls. Results suggest that increased [Mg2+]i and altered Ca2+ handling by platelets may be associated with coronary vasospasm.

Characterization of the integrin alpha(v) gene promoter in mice

To characterize a promoter for integrin alpha(v) in mice, we cloned a 5'-flanking region of the mouse integrin alpha(v) gene. The nucleotide sequence of the promoter region lacks both TATA or CCAAT boxes, and has the consensus sequence for Sp1, Ets, AP-2 and GATA-1. The transcription initiation site was mapped as 287 base pairs (bp) upstream from the translation initiation site by primer extension analysis. To analyze the promoter activity of the integrin alpha(v) gene, the successive 5'-deletions which were cloned upstream of the luciferase reporter gene were transfected into mouse melanoma B16F10 cells with high metastatic properties. The luciferase assay reveals that a region (positions -108 to +22) has important cis-acting elements for the promoter activity. Further, three distinct protein-DNA complexes in the promoter region were detected in a gel shift assay using nuclear extracts from B16F10 cells. To identify positions where the complexes are formed, the promoter region (positions -108 to +97) was subjected to DNaseI footprinting analysis. The analysis showed that a 17 bp-element (positions -31 to -15) interacts with putative transcription factors. Deletion of the 17 bp-element from the promoter resulted in a reduction of about 80% in the promoter activity when compared with the wild type promoter, and a gel shift assay using the deleted mutant of the promoter showed only one protein-DNA complex. These results reveal that the 17 bp-element contains cis-acting elements, and plays an important role in the transcription initiation of the integrin alpha(v) gene.

[The present and future of clinical physiologic tests]

The symposium on clinical physiologic tests was designed in the 44th congress of all central laboratory divisions of national university hospitals at 28, 29 May in 1997. The title of symposium was "the present and future of clinical physiologic tests" which was named by professor M. Itoh. Four symposists were nominated among the specialists on clinical physiologic tests of members of above congress. Professor M. Itoh and Professor H. Kawaguchi spoke about Erectric Cardio Graphy (ECG) and main heart function tests and Professor M. Kambe spoke about pulmonary function tests and Professor M. Okada spoke about the using methods of clinical physiologic test data in remote and distant medicine. The special feature of clinical laboratory division in Japanese large hospitals is that has clinical physiologic tests part and the clinical laboratory division of hospitals in foreign countries has no clinical physiologic tests part. So, we expect more development of clinical physiologic tests part in nearly future.

Nonadrenergic, noncholinergic inhibitory innervation in the longitudinal muscle of the rabbit portal vein

1. We examined whether nitric oxide (NO) and ATP take part in inhibitory nonadrenergic, noncholinergic (NANC) neurotransmission in the portal vein of Japanese White rabbits. Longitudinal strips of the vein were suspended in organ baths containing Krebs bicarbonate solution. Preparations relaxed in response to electrical field stimulation (EFS) (25 V, 0.5 msec in duration, 1-50 Hz) and exogenous ATP (1-300 microM) after contraction was induced with 10 microM ergotamine in the presence of 3 microM guanethidine and 0.1 microM atropine. 2. The relaxation response to EFS was abolished by addition of 100 microM NG-nitro-L-arginine, an NO synthase inhibitor. This abolition was partly reversed by 10 mM L-arginine, a substrate for NO synthase. 3. The relaxation response to exogenous ATP was significantly inhibited by 1 mM suramin, a P2X- and P2Y-purinoceptor antagonist, whereas relaxation response to EFS was not inhibited by 1 mM suramin. 4. From the results of this study, we conclude that the inhibitory NANC neurotransmission is mediated by NO alone and does not involve ATP in the portal vein of Japanese White rabbits under our experimental conditions.

Differential effects of extracellular Mg2+ on thrombin-induced and capacitative Ca2+ entry in human coronary arterial endothelial cells

Receptor-mediated and capacitative Ca2+ entry are the primary Ca2+ entry pathways in endothelial cells (ECs). The mechanisms for Ca2+ entry via these pathways have not been fully elucidated. In this study, the effect of low and high external Mg2+ concentrations on these Ca2+ entry pathways was examined in human coronary arterial ECs. External Mg2+ concentration did not affect cytosolic free Mg2+ concentration. After exposure to thrombin in Ca(2+)-free medium, addition of Ca2+ to the medium caused a rise in cytosolic free Ca2+ concentration ([Ca2+]i), indicating thrombin-induced Ca2+ influx. Thrombin-induced Ca2+ influx was inhibited by not only low but also high external Mg2+ concentrations. After depletion of endoplasmic Ca2+ stores by thapsigargin, addition of Ca2+ to the medium induced an increase in [Ca2+]i, indicating capacitative Ca2+ entry. Capacitative entry was found to be accelerated by low external Mg2+ and inhibited by high external Mg2+ concentration. Results suggest that receptor-mediated Ca2+ influx requires external Mg2+ but is inhibited by increased external Mg2+ concentrations and that capacitative Ca2+ entry is reduced by external Mg2+ in human coronary arterial ECs.

Lack of effect of transmembrane gradient of magnesium and sodium on regulation of cytosolic free magnesium concentration in rat lymphocytes

The regulation of the intracellular concentration of Mg2+ ([Mg2+]i) is not fully understood. The level of Mg in lymphocytes is a good predictor of total body Mg status. We measured [Mg2+]i and total Mg in rat lymphocytes by using, respectively, the fluorescent Mg2+ indicator mag-fura-2 and atomic absorption spectrophotometry. The basal [Mg2+]i in rat lymphocytes was 328 +/- 23 micromol/l. An elevation to 5 mmol/l or the removal of extracellular Mg2+ did not affect [Mg2+]i. A reduction in extracellular Na+ did not influence [Mg2+]i for 60 min. The total Mg concentration in lymphocytes also remained stable. Results suggest that the permeability of the plasma membrane to Mg2+ is very low, and that Na+/Mg2+ exchange is not involved in the regulation of [Mg2+]i in rat lymphocytes.