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Changes in cytoplasmic free calcium levels and membrane fluidity of platelets in contact with poly(acrylamide-co-methacrylic acid) (PAAmMAc) particles were examined to analyze the mechanistic aspect of regulating platelet function. Our previous studies demonstrated interesting features of PAAmMAc particles during interaction with platelets: (1) PAAmMAc particles induce no calcium increase but enhance membrane fluidity of platelets: (2) thrombin induces no calcium increase in platelets when the platelets were mixed previously with PAAmMAc particles; and (3) PAAmMAc particles induce a calcium increase in platelets when they were treated previously with sodium azide (NaN3). These results suggest the possibility that PAAmMAc surfaces may regulate the calcium level by influencing platelet metabolism. In this study, non-cross-linked PAAmMAc solution with the same chemical composition as the particles showed a suppressive effect on thrombin-induced calcium increase, but, no influence on membrane fluidity. This result indicates that aggregated macromolecular surface assemblies of PAAmMAc may dominate the increase in membrane fluidity of platelets although the calcium change is induced by discrete molecular level interaction between the PAAmMAc and platelet membranes. It was also revealed that the suppression of thrombin-induced calcium increase and the membrane fluidity increase in platelets by PAAmMAc particles were reduced by albumin-treatment of the particles. This result suggests that such phenomena may be due to a decrease in any physicochemical interaction of PAAmMAc surfaces with albumin, rather than platelet metabolic change. PAAmMAc particle surfaces with higher carboxyl groups exhibited a more suppressive effect on thrombin-induced calcium increase, whereas those with lower carboxyl groups derived a higher calcium increase when the platelets were treated previously with NaN3. These results suggest the importance of electrostatic and any other physicochemical interaction of PAAmMAc chains on regulating cytoplasmic calcium levels.

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, pravastatin (Pr) and simvastatin (Si), suppressed 1,2-dimethylhydrazine (DMH)-induced colon cancer development in female ICR mice. All mice received an i.p. injection of 10 mg DMH/kg body wt once weekly for 15 weeks. Pr was administered at 0.01, 0.005 and 0.001% levels in drinking water, and Si at 0.01 and 0.002% levels in the diet. All animals had access to Pr or Si throughout the experiments which were terminated at weeks 25 or 30. Histologically most of the tumors were well-differentiated adenocarcinomas. The incidence of colon tumors examined at weeks 25 or 30 was reduced by 67% in the 0.01% Pr group, by 30% in the 0.005% Pr and 0.01% Si groups, and by 24% in the 0.001% Pr and 0.002% Si groups, compared with their respective controls. However, the differences did not reach statistical significance. The number of tumors per mouse was significantly reduced in all groups administered Pr and Si except the 0.001% Pr group as compared to their respective controls. The results from those three independent experiments seem to suggest that HMG-CoA reductase inhibitors may prevent colon tumorigenesis in laboratory animal model.

Changes in cytoplasmic free calcium levels ([Ca2+]i) in platelets in contact with polystyrene (PSt) and poly(acrylamide-co-methacrylic acid) (PAAmMAc) particles were evaluated and results were compared with those from two representative biological calcium agonists; thrombin and calcium ionophore A23187. PSt particles stimulated a steep increase in cytoplasmic calcium levels in platelets as much as thrombin and A23187. Serratia protease-treated platelets showed a steep increase in [Ca2+]i by PSt particles, suggesting that PSt surfaces can initiate platelet activation independent of a glycoprotein Ib (GPIb)-mediated pathway. By contrast, dibucaine-treated platelets showed little increase in [Ca2+]i by PSt particles, indicating that microfilament assembly, including binding of GPIb with actin binding protein, should be required for platelet activation in contact with PSt surfaces. PAAmMAc particles induced little increase in cytoplasmic calcium levels in platelets. However, PAAmMAc particle-treated platelets demonstrated little response to thrombin in terms of an increase in [Ca2+]i and ATP release, suggesting the possibility that PAAmMAc surfaces may regulate [Ca2+]i by influencing platelet metabolism. Furthermore, sodium azide-treated platelets showed an increase in [Ca2+]i in platelets when contacting PAAmMAc particles, supporting the suggestion that PAAmMAc surfaces could regulate platelet functions. Fluorescence polarization measurements using 1,6-diphenyl-1,3,5-hexatriene-loaded platelets revealed that PAAmMAc particles increased membrane fluidity in platelets, which may be due to physicochemical interaction with PAAmMAc surfaces.

The frequency of a visceral mycosis grows definitely higher with an immunocompromised host. Invasive fungal infection can be controlled by means of development of early diagnosis and antifungal therapy. In these types of cases, it is difficult to establish an antemortem diagnosis of invasive pulmonary aspergillosis and most of them were diagnosed postmortem. A patient was diagnosed as aspergillosis from the clinical and serological features. This patient underwent successful therapy during remission induction therapy of acute myelocytic leukemia (AML). A 26-year-old male was admitted to our hospital because of leukocytosis with a diagnosis of AML made by reviewing peripheral blood smears and bone marrow aspirate. After remission induction therapy, he was still febrile in spite of treatment with a broad spectrum antibiotics and empiric therapy of fluconazole. Unfortunately shadowing appeared on the chest radiograph and aspergillus antigen was detected from the serum and the sputum. Consequently, the patient who suffered from invasive pulmonary aspergillosis was diagnosed and treated with intravenous amphotericin B and flucytosine. The radiological shadow improved but AML relapsed, therefore, remission induction therapy of AML was started again but he died of sepsis caused MRSA. In the postmortem histopathological examination the lung tissues, the hyphae could not be confirmed while, in immunohistochemical examinations of the lesion at the left S8, aspergillus antigens were detected around the small necrotic lesions and in the polymorphologic giant cells. We emphasize that invasive pulmonary aspergillosis is very difficult to diagnose whereas active examinations and clinical early diagnosis may lead to more effective therapy and the prognosis.

Two kinds of water-soluble chlorophyll-protein complexes were prepared from leaves of Lepidium virginicum L., one (CP661) from the plant cultivated in a green house from seeds collected near Mono Lake, CA, and the other (CP-663) from a plant collected at Narashino, Chiba, Japan, by ammonium sulfate fractionation followed by column chromatography on DEAE-cellulose and Sephacryl S-200. The chlorophyll . proteins were further purified by crystallization. CP661 has absorption peaks at 661, 468, 439, 419, 380, 339 and 272 nm. CP663 had absorption peaks at 663, 469, 438, 419, 379, 338 and 272 nm. Estimated molecular weights were 78 000 for CP661 and 80 000 for CP663 by gel filtration chromatography and 83 000 for CP661 and 107 000 for CP663 by an equilibrium sedimentation method. 1 mol chlorophyll . protein contained 4 mol chlorophyll a and b with ratios of 1.0 in CP661 and 1.6 to 1.9 in CP663, but no carotenoids. These characters are different from those of chlorophyll-protein complexes which are prepared from the thylakoid membranes of chloroplasts with detergents.

To study the effect of fluid shear stress on cultured endothelial cells, we have developed an apparatus for the stress creation, which consists of a stainless steel disk driven by an electric DC motor and a stage to place a culture dish and to adjust the distance between the disk and the dish. When the disk is rotated, a concentric fluid movement occurs in the culture medium in the dish and exerts the shear stress on the endothelial cells cultured on the bottom of the dish. A theoretical analyses concerning the induced concentric flow velocity predicted that when the angular velocity of the disk rotation (omega) is slow enough to maintain a Reynolds' number of the order of 10, the exerted wall shear stress tau w on the endothelial cell monolayer is given for a constant as tau w = mu r omega/d where mu is the viscosity of the medium, d the distance from the plate to the monolayer and r the radial distance from the center of the dish. When omega is varied in a sinusoidal mode tau w also becomes sinusoidal, thus allowing to apply a pulsatile stress. In vitro experiments carried out to examine the validity of the theoretical results, using a suspension of polystyrene as a tracer with the ordinary culture medium and 99% ethanol, revealed excellent agreement of the measured velocity profiles with the predicted ones. The results demonstrated that the present apparatus can create both the steady and pulsatile wall shear stress on the culture cell layer as expected, unless Reynolds' number greatly exceeds the level of 10.

About 5,000 strains of marine microorganisms were screened for eicosapentaenoic acid (EPA)-producing ability, which was detected in 88 of them. All of the latter were found to be obligate aerobic, Gram-negative, motile, short rod-shaped bacteria. One strain, designated as SCRC-8132, showed a doubling time of 30 min at 25 degrees C and produced 20 mg/liter (4 mg/g dry cells) when cultured in a P-Y-M-Glucose medium for 18 h. The EPA to total fatty acids ratio was 24%. The strain produced 26 mg EPA/liter (15 mg/g dry cells) when cultured at 4 degrees C for 5 days, the EPA ratio being increased to 40%.

Preliminary crystallographic studies of a Bowman-Birk type protease inhibitor, AB-I, from adzuki beans (Phaseolus angularis) 'Takara,' and its complex with trypsin were carried out. AB-I, MW 9100 with 82 amino acid residues, crystallizes in a trigonal space group, P3121 (or P3221), with the following unit cell dimensions: a = 68.7, c = 99.7 A. The asymmetric unit contains two dimer molecules. Structure analysis at 5 A resolution revealed the rough appearance of the dimer. The complex between AB-I and trypsin also could be crystallized in a tetragonal space group, P41212 (or P43212), with the unit cell dimensions, a = 55.4 and c = 181.5 A, and Z = 8. The crystallinity seems to be much better than that of the crystals of the inhibitor alone. The other type of inhibitor from adzuki bean, AB-IIa, was also crystallized.

The crystal structure of the complex formed by bovine trypsin and Bowman-Birk type protease inhibitor AB-I extracted from azuki beans (Vigna angularis) 'Takara' has been analyzed. The structure was solved by the application of the phase combination of single isomorphous phases and trypsin model phases, followed by phase improvement using the iterative Fourier technique. From the resulting electron density map, a three-dimensional atomic model of the trypsin binding domain of AB-I has been built. The peptide chain at the trypsin reactive site turns back sharply at Pro29 and forms a 9-residue ring (Cys24-Cys32). The 'front side' of this ring, consisting of the reactive site (Cys24-Met28), interacts with trypsin in a similar manner to other families of inhibitors and forms a stable complex, which seems to be maintained by the interactions with the 'back side' of this ring (Pro29-Cys34). The similar spatial arrangements of the 'back side' of this inhibitor and the 'secondary contact region' of the other inhibitors with respect to the reactive site suggest an important common role of these regions in exhibiting inhibitory activity.

Double-headed protease inhibitors I, IIa, and IIc (AB I, AB IIa, and AB IIc) have been purified from azuki beans "Takara" (Vigna angularis) by conventional chromatographic methods and their amino acid sequences have been determined. AB I, AB IIa, and AB IIc had molecular weights of 9,166, 8,661, and 8,756 daltons, consisting of 82, 78, 79 amino acid residues, respectively. The molecular weights of these inhibitors, determined by gel filtration at pH 8.0, were 18,000 for AB I and 17,000 for both AB IIa and AB IIc, indicating that the inhibitors are dimers. The inhibitors had isoelectric points of 4.7 (AB I), 6.8 (AB IIa), and 6.2 (AB IIc). AB I stoichiometrically inhibited both trypsin and chymotrypsin at a molar ratio of 1 : 1. On the other hand, AB IIa and AB IIc both inhibited trypsin at a molar ratio of about 1 : 2 and also inhibited chymotrypsin, though only weakly. Sequence comparison with other double-headed inhibitors indicated the reactive sites of AB IIa and AB IIc for trypsin to be Lys26-Ser27 and Arg53-Ser54, and those of AB I for trypsin and chymotrypsin to be Lys26-Ser27 and Tyr53-Ser54, respectively. The differences between AB IIa and AB IIc were that AB IIa lacked the C-terminal aspartic acid residue, and that Glu10 and Arg60 in AB IIa were replaced by Gln10 and His60 in AB IIc. A comparison between AB IIa and AB I revealed 25 variant amino acids among the 78 residues of AB IIa; further, Ab IIa lacked 4 amino acid residues in the C-terminal region of AB I.

In order to chemically remove the calculus adhering to a denture, new denture cleaner was prepared on an experimental basis. The principal ingredient of this solution was a chilating agent which contained the phosphoric acid. This study consisted of the fundamental and the clinical examinations of this solution the purpose of which was to test the solvent power of this solution on the calculus and to evaluate its influence on the denture materials and its effectiveness in clinical practice. 1. the fundamental study 1) method (1) The test for the solvent power of this solution. The powder of tricalcium phosphate (T.C.P. powder: Wakohjunyaku Co.) was substituted for the calculus adhering to a denture. (1) The influence of the solution temperature on the solvent power. The T.C.P. powder was dissolved at 20 degrees C, 30 degrees C, 40 degrees C, 50 degrees C and 60 degrees C temperature in 10 g of the solution within 10 minutes and the amount of dissolved powder was weighted. The time was measured with a stop watch (Seiko Co.) until 0.5 g of T.C.P. powder had been dissolved in 10 g of the solution. (2) The effect of using it with an ultrasonic cleaner. The time to dissolve 0.1 g of T.C.P. powder in 10 g of this solution was compared with that of the 15% EDTA solution. The measurement was repeated 5 times and the arithmetic mean of the 5 sample values was calculated in order to show the experimental results. The room temperature was 19 +/- 2 degrees C, the humidity was 56 +/- 3%. (2) The influence of this solution on the denture materials. (1) resin specimen. In order to test the transverse strength, transverse deflection, Young's modulus and Knoop hardness, resin specimens were processed in the manner specified in I.S.O. 1567. The data were compared the resin specimens steeped in this solution and with the control sample that was steeped in water. The specimens were immersed up to 24 hours. Furthermore the existence of tarnish was observed with a 40 times microscope. (2) metal specimen. In order to test the corrosion, metal specimens were produced according to the manner of a corrosion test. The metal specimens were held vertically and the end immersed to 20 mm in this solution for 24 hours and 120 hours each. After steeping, each specimen was measured for loss in weight. The data were calculated as the loss in weight per hour (mg/cm) and the depth of corrosion per year (mm/yr).(ABSTRACT TRUNCATED AT 400 WORDS)

The purpose of this study was to estimate masticatory efficiency of complete denture wearers. The subjects were 72 patients, treated before 5-10 years at students' clinic of Tsurumi University, School of Dental Medicine. The masticatory efficiencies with peanuts and Kamaboko were calculated. Results 1. The mean masticatory efficiency with peanuts for 63 patients was 35.8%, and with Kamaboko (steamed fishpast) for 64 patients was 94.5%, in comparison with natural dentition. 2. The mean masticatory efficiency with peanuts was 124.3%, and with Kamaboko was 99.6%, for complete denture wearers. 3. Comparing the measured value of masticatory efficiency with 5 to 10 years wearing period, there was significant difference in the masticatory efficiency between peanuts and Kamaboko. 4. There was significant difference in the masticatory efficiency with peanuts between the group needed new denture and the group not needed but there was not significant difference with Kamaboko.