Effect of gomisin A (TJN-101) on the arachidonic acid cascade in macrophages

It has been reported that leukotrienes (LTs) may play a role in inflammatory liver diseases, and several inhibitors of LTs show an inhibitory effect on experimental liver injuries. In this study, the effect of Gomisin A (TJN-101), which is a lignan component of schisandra fruits, on the arachidonic acid cascade in macrophages was examined to explain the mechanisms of the inhibitory effect of TJN-101 on liver injuries. The production of leukotriene B4 was suppressed by treatment with TJN-101, while the activity of 5-lipoxygenase was not affected. The release of arachidonic acid from macrophages stimulated with fMet-Leu-Phe or the Ca++ ionophore A23187 was suppressed by treatment with TJN-101. The activity of phospholipase A2 was not affected by treatment with TJN-101. These results suggested that TJN-101 produces an inhibitory effect on the biosynthesis of LTs by preventing the release of arachidonic acid, and it was thought that the preventive effect on the arachidonic acid cascade may be partially associated with the inhibitory effect of TJN-101 on liver injuries.     

Movement of the lateral and medial poles of the working condyle during mastication in patients with unilateral posterior crossbite.

Patients with unilateral posterior crossbite often show reverse sequential jaw movement patterns on the frontal view during mastication on the crossbite side. Recent studies show that such patients are prone to suffer from temporomandibular joint (TMJ) disc displacement, particularly the lateral portion. The purpose of this study was to examine the movement of the lateral and medial poles of the working condyle during mastication in such patients. Subjects were 12 consecutive patients with unilateral posterior crossbites and without TMJ disc displacements and 12 normal subjects. An optoelectronic jaw-tracking system with 6 degrees of freedom was used to record the motion of the lateral and medial poles of the working condyle during mastication of standardized hard, gummy jelly. The data from the first 10 cycles were analyzed. The lateral and medial poles of the condyle on the crossbite side moved more in the medial direction and less in the lateral direction during mastication in the crossbite patients than the condyle in the normal subjects. The lateral pole of the working condyle moved more in the posterior and inferior directions and less in the anterior direction than the medial pole in all subjects. These results suggest that these condylar movements in patients with unilateral posterior crossbites might be related to the susceptibility to TMJ disc displacement, particularly the lateral portion.     

Drug Binding to α1-Acid Glycoprotein Studied by Circular Dichroism

The interactions of acidic and basic drugs with ₁-acid glycoprotein (₁-AGP) were investigated using circular dichroism (CD) measurements. Extrinsic Cotton effects were generated by the binding of drugs to ₁-AGP. The CD data suggested the presence of a single binding site on the ₁-AGP molecule. The induced ellipticities of the acidic drug–₁-AGP system decreased with increasing pH, while the ellipticities for the basic drugs increased with pH. The ellipticities for all drugs were reduced by the addition of fatty acids. Furthermore, the induced ellipticities decreased in the presence of cesium chloride for basic drugs bound to ₁-AGP. The extrinsic Cotton effects therefore appear to result from hydrophobic interaction with ₁-AGP for the acidic drugs and from hydrophobic and electrostatic interactions for the basic drugs.     

Basic and clinical evaluation of an immunoradiometric competitive inhibition assay for 2----6 sialyl Lewis a antigen--1. Evaluation of assay conditions and normal values

We describe an immunoradiometric competitive inhibition assay of the serum levels of the 2----6 sialyl Lewisa antigen, using "SLA 2-6 Otsuka" kits. The assay required only duplicate 50-microliters samples, and the concentration of 2----6 sialyl Lewisa antigen in serum was determined by reference to a standard curve ranging from 0 to 160 arbitrary U/ml. The intra- and inter-assays reproducibilities were good and analytical recovery of antigen were excellent. The serum levels of the antigen were highly dependent on the Lewis blood types of the tested individuals; i.e., the levels of the antigen in the sera of the Lewisa-b- individuals were significantly lower than those of the antigen obtained with the Lewisa+b- and Lewisa-b+ individuals. The cut-off value (42 U/ml) was obtained as mean + 2SD, which was carefully calculated from the antigen levels in sera of the non-Lewisa-b- individuals.     

Analysis of small dense LDL in patients with type 2 diabetic mellitus by the modified Krauss method using an internal standard

In patients with Type 2 diabetes mellitus (Type 2 DM), the relationship between the prevalence rate of small dense LDL (sdLDL) and parameters of lipid metabolism was analyzed using the method devised by modified Krauss method using apoferritin as an internal standard. The prevalence rate of sdLDL was 34% compared with it of normal subjects in this study. When the severity of Type 2 DM was classified into three groups of the HbA1c value, neither the sdLDL size nor its prevalence rate differed significantly depending upon the severity of the Type 2 DM. Also, when the prevalence rate of sdLDL was analyzed in relation to the severity of complications, i.e., of microangiopathy (retinopathy and nephropathy) or macroangiopathy (cerebral infarction), there was no significant difference in the prevalence rate of sdLDL depending on the severity of any of these complications. On the other hand, the prevalence rate of sdLDL was found to be correlated with the serum TG level. The serum level of TG-rich remnants (metabolites of TG) was also high in patients with sdLDL. It should take notice that the assessment of sdLDL should be used the authorized method for the evaluation. Thus it is concluded that the levels of sdLDL were important in evaluation of Type 2 DM. The prevalence rate of sdLDL did not correlate with the severity, nor the modalities for the complications of Type 2 DM.     

Evaluation of time-resolved fluorometric immunoassay of CA 50

Serum CA 50 was determined by a time resolved fluorometric immunoassay (TR-FIA) with CANAG CA-50 DELFIA kit. Evaluation of the assay system gave satisfactory results in its sensitivity, accuracy, reproducibility, dynamic range and easy handling. No prozone phenomenon was observed up to 347,000 U/ml. From a histogram of 134 normal sera, the cut off point was determined at 34 U/ml. CA 50 in 202 patients' sera was determined with this assay. Nineteen of 20 patients pancreatic cancer, 6 of 21 gastric cancer, 14 of 25 hepatoma gave positive values. In comparison with CA 19-9, higher values and higher rates of positive CA 50 were observed in benign and malignant liver diseases, suggesting its non-cancerous origin in the liver. A high correlation was observed between the level of CA 50 and CA 19-9 of 157 patients' sera. Serum CA 50 was completely correlated with CA 19-9 in the clinical course of patients with pancreatic cancer, but not in patients with hepatoma. Thus we conclude that the CANAG CA-50 DELFIA System is useful for the diagnosis and monitoring cancer patients but must be used with care because of its elevation in benign liver diseases.     

Tumor necrosis factor-alpha in the placenta is not elevated in pre-eclamptic patients despite its elevation in peripheral blood

PROBLEM: Tumor necrosis factor-alpha (TNF-alpha) is present in human placental and uterine cells at the early and late stages of gestation and promotes the regulation of trophoblast growth and invasion. We evaluated whether TNF-alpha levels in the placenta and blood of pre-eclamptic women differed from those with normal pregnancies. METHOD OF STUDY: The subjects were 39 pregnant women carrying single fetuses (21 normal-pregnant and 18 pre-eclamptic patients). Their average gestational age at entry was 38-39 weeks. Peripheral blood was collected before the onset of labor and separated serum was stored at -20 degrees C. A tissue segment of the placenta was cut and frozen in liquid nitrogen immediately after delivery at -80 degrees C. The frozen placental tissue was added to phosphate-buffered saline. The tissue was fully homogenized and centrifuged. Separated supernatant was stored at -80 degrees C. TNF-alpha levels in separated serum and TNF-alpha and total protein (TP) levels in separated supernatant were measured. The presence of TNF-alpha in the placenta was evaluated by immunohistochemistry in five pre-eclamptic and five normal-pregnant patients. RESULTS: Serum TNF-alpha levels were higher in pre-eclampsia than in normal pregnancies. However, TNF-alpha/TP levels in the placenta did not differ significantly between the two groups. As for TNF-alpha immunostaining of trophoblastic cells in the placenta, it was weak in three and moderate in two of the normal pregnancies, while it was absent in two, weak in one, and moderate in two in the pre-eclampsia group. CONCLUSIONS: We demonstrated no significant increase in TNF-alpha/TP levels in the placenta in pre-eclampsia despite a significant increase in serum TNF-alpha levels. There was no strong immunostaining for TNF-alpha detected by immunohistochemistry in the pre-eclampsia group. These findings suggest that TNF-alpha in the placenta is not a key cytokine to interfere with normal trophoblast invasion into the myometrium in pre-eclampsia, and that sources other than the placenta may contribute to the elevated levels of TNF-alpha found in the circulation of pre-eclamptic patients.     

cAMP-independent decrease of ATP-sensitive K+ channel activity by GLP-1 in rat pancreatic β-cells

Using the patch-clamp method, we studied the mechanism of depolarization of rat pancreatic beta-cells induced by glucagon-like peptide 1 (7-36) amide (GLP-1). GLP-1 caused depolarization in a concentration-dependent manner (0.2-100 nM). Exendin (9-39) amide, a GLP-1 receptor antagonist, prevented the GLP-1-induced depolarization. GLP-1 reduced tolbutamide-sensitive membrane currents evoked by voltage ramps from -90 to -50 mV, recorded in the perforated whole-cell configuration, suggesting that GLP-1 decreased the activity of the ATP-sensitive K+ channel (KATP). This GLP-1 effect was prevented by exendin (9-39) amide. In cells treated with Rp-cAMPS, an inhibitor of the cAMP-dependent protein kinase (PKA), GLP-1 still caused depolarization and reduced the whole-cell membrane current through KATP. Examined in the cell-attached configuration, 20 nM GLP-1, applied out of the patch, had little effect on KATP activity. In the inside-out configuration, the open time probability and the single-channel conductance of KATP in the absence of ATP inside the membrane were unaffected by the presence of 20 nM GLP-1 in the pipette. In both conditions, application of ATP to the inside of the membrane reduced KATP activity. The half-maximal concentrations (ki) of ATP were 11.6 microM without and 5.6 microM with 20 nM GLP-1 in the pipette (P<0.05). The values of the Hill coefficient (h) were 1.03 without and 1.01 with GLP-1. We conclude that GLP-1 reduces KATP activity by elevating the sensitivity of KATP to ATP, resulting in depolarization of pancreatic beta-cells. This GLP-1 action is independent of the cAMP signalling pathway.     

Development of sandwich radioimmunometric assay for serum c-erbB-2 oncogene product and its significance in diagnosing breast carcinoma]

A sandwich radioimmunometric assay using monoclonal antibodies 6G10 and SV2-61 gamma directed to the extracellular domain of the c-erbB-2 oncogene product was developed and the antigen levels in sera from normal donors and patients with breast carcinoma were determined. The antigen levels in normal donors were uniformly low (9.52 +/- 0.91 ng/ml) and 3.0% (2/66 cases) slightly exceeded the cutoff value (11.4 ng/ml). In patients with breast carcinoma, serum c-erbB-2 protein levels increased and the positivity was as high as 45.7% (16/35 cases) in recurrent cases. Determination of c-erbB-2 protein may be a useful marker for serological diagnosis of breast carcinoma.