Gas-liquid chromatographic determination of vitamin D in tuna liver and vitamin D resin oils.

Gas-liquid chromatographic (GLC) determination of vitamin D3 in tuna liver and vitamin D3 resin oils was investigated and a routine method slightly modified from the previously reported methods (1, 2) was established. Since both tuna liver and vitamin D3 resin oils contained large amounts of sterols, digitonin-Celite column chromatography according to SHEPPARD et al.(4) was used to remove the sterol influence from the unsaponifiable matters of the oils. After collecting the eluate and evaporating the solvent, the residue was subjected to thin-layer chromatography (TLC) using Kieselgel GF254 as an adsorbent and a mixture of n-hexane-ethyl acetate (4: 1) as a developing solvent. The scraped zones corresponding to vitamin D3 and pre-D3 were trimethylsilylated and then applied to the GLC using 1.5% OV-17 packed on Shimalite W (80-100 mesh) as a stationary phase. Trimethylsilylation of the gas chromatograms was an essential procedure, because the peaks of unknown substances in tuna liver oils and lumisterol in vitamin D3 resin oils could not be separated from the peak of pyro-D3 without trimethylsilylation. When the proposed method was applied to the samples, satisfactory results were obtained.     

MR imaging in the assessment of lung cancer patients: primary lung cancer staging, evaluation of therapeutic effect and diagnosis of recurrent tumor

Magnetic resonance imaging and computed tomography were compared in a prospective study of 137 lung cancer patients proved by surgery or autopsy for determining the staging, evaluation of therapeutic effect and diagnosis of recurrent tumor. 1. Lung cancer staging In peripheral lung cancer, T1 and T2 relaxation times of the tumors before operation have some correlation with those of operated specimens. These relaxation times, however, are of limited nodule characterization. Hilar mass and adjacent pulmonary consolidation (obstructive pneumonia or collapse) can be distinguished on T2-weighted image (77%) and Gd-DTPA enhanced image (80%). Therefore these images help in distinguishing tumor from peripheral lung disease. In the diagnosis of tumor invasion to the heart and great vessels, MRI is superior to CT because MRI can be helpful in distinguishing true mass from heart and great vessels. As for the chest wall, MRI is more useful than CT in detecting tumor invasion especially to the thoracic inlet and superior regions. In the diagnosis of mediastinal and hilar lymphadenopathy, MRI is equivalent or slightly inferior to CT, but MRI can easily demonstrate the lymphadenopathy at subcarinal region on coronal image. 2. Evaluation of therapeutic effect in lung cancer patients treated by radiation and chemotherapy MRI patterns of therapeutic effect was divided into 3 types. It is suggested that there is some correlation between these patterns and histologic types. MRI can easily demonstrate necrotic area on T2-weighted and Gd-DTPA enhanced images. 3. Diagnosis of recurrent tumor in treated lung cancer Concerning detecting recurrent tumor after surgery or irradiation, and delineating tumor from radiation pneumonitis, T2-weighted and Gd-DTPA enhanced images are of clinical value.     

Improvement of dissolution characteristics of 4-t-butyl-2′-car☐ymethoxy-4′-(3-methyl-2-butenyloxy)chalcone by β-cyclodextrin complexation

The inclusion complexation of 4-t-butyl-2′-car☐ymethoxy-4′-(3-methyl-2-butenyloxy)chalcone (SU-740), a newly developed antiulcer agent, with β-cyclodextrin (β-CyD) in water and in solid state was investigated for the purpose of improving the low aqueous solubility and oral bioavailability. SU-740 formed 1:1 and 1:2 (guest:host) inclusion complexes in water and in the solid state and the 1:1 stability constant was much higher than the 1:2 stability constant. The dissolution rate of SU-740 was significantly improved by the complexation with β-CyD, suggesting the enhanced bioavailability.     

Deficiency of P62, a putative collagen receptor, in platelets from a patient with defective collagen-induced platelet aggregation.

Recently, we described a platelet antibody against a putative collagen receptor (P62), which was found in a patient with idiopathic thrombocytopenic purpura (ITP) (Blood 69:1712). We now report a deficiency of the P62 receptor in a young man whose platelets showed defective collagen-induced platelet aggregation. He had a mild bleeding tendency and slight thrombocytopenia. The results of coagulation and fibrinolysis studies were normal. The patient's platelets were partially unresponsive to collagen, although aggregation in response to ADP, thrombin, ristocetin, and calcium ionophore (A23187) was almost normal. Adhesion of his platelets to bovine collagen was markedly reduced. Addition of collagen caused no synthesis of thromboxane (TX)B2 in platelet rich plasma (PRP) from this patient. Furthermore, collagen produced no rise of cytosolic free calcium ([Ca2+]i) in fura2-loaded platelets. In contrast, thrombin caused TXB2 formation and an increase of [Ca2+]i in his platelets. These results suggest defective interaction between the platelets and collagen. The IgG from the ITP-patient induced irreversible aggregation in normal PRP, but caused no aggregation of the young man's platelets. Immunoblot studies showed that normal platelets had antigens with a molecular weight of 62 KDa under reducing conditions and of 57 KDa under nonreducing conditions. In contrast, the young man's platelets had no P62 band, although GPIa/IIa and thrombospondin were normally present. These results indicate that impaired collagen-induced aggregation in the patient's platelets was due to a deficiency of P62 and confirm that P62 may play a crucial role as a collagen receptor in platelet activation.