Natural history of diabetes mellitus with special reference to age of onset and vascular complications

Age and sex distribution of diabetics, seasonal incidence of diabetes, grade of hyperglycemia, frequency of vascular complications and daily living conditions were studied of 2771 diabetic patients experienced at five clinics. The cases consisted of 1587 male and 1184 female diabetics. The distribution of age of diabetes onset revealed that males predominate among diabetics but females predominate among child diabetics, and that the precentage of child was extremely low. This pattern was emphasized as characteristic of Japanese diabetic population. Distribution of fasting blood sugar at the diagnosis of diabetes was compared among the age groups of diabetes-onset and the results showed that percentage of the value exceeding 300 mg/100 ml was highest in the under 10 year-onset cases and decreased with age. The frequency of diabetic retinopathy and of ischemic ECG changes was analysed from the view point of age of diabetes onset and also the duration of the disease. The frequency of the retinopathy at the diabetes-onset was zero in the under 10 year-onset cases, 4.2% in the 10s-onset cases and increased with age. The longer the duration of the disease the higher the frequency of the retinopathy was. This increase along with the duration was most remarkable in the 10s- and 20s-onset cases and less remarkable in the 30s-onset cases. The retinopathy was significantly more frequent in female diabetics. Daily of the patients were studied by a questionnaire and the analysis of 1022 cases with diabetes of more than three years revealed that cases of patients working uneventfully and/or feeling fit were most frequent among the 30s- or 40s-onset cases and that cases of bed-disability were frequent among the cases whose diabetes was found in their twenties or younger. This study showed that the prognosis of the patients is quite different according to whether their diabetes occurred before of after 30 years of age.     

Further studies on the possible compartmentation of the precursor pool of cholesterol for the biosynthesis of cholic acid in the rat

In vivo and in vitro experiments with rats were carried out to investie precursor for the biosynthesis of cholic acid. When rats with a bile-fistula were given a mixture of [2-14C]mevalonate and [1,2-3H]cholesterol intravenously, the 14C:3H ratio in cholic acid in both whole homogenate and cytosol prepared from their lives was higher than that in free cholesterol in any subcellular fraction of the livers. When [2-14C] mevalonate was administered intravenously to bile-fistula rats, the specific radioactivity of free cholesterol in the hepatic microsomal fraction exceeded that in any other fraction, and the specific radioactivity of biliary cholic acid was remarkably high, exceeding that of microsomal free cholesterol. In similar experiments with [4-14C] cholesterol, the specific radioactivity of free cholesterol in the hepatic microsomal fraction exceeded that in any other subcellular fraction and the specific radioactivity of biliary cholic acid was lower than that of free cholesterol in any hepatic subcellular fraction. Tissue suspensions of rat livers in Krebs-Ringer bicarbonate (pH 7.4)-5.5 mM glucose were incubated with [2-14C]mevalonate in O2-CO2 (95:5, v/v) at 37 degrees. The specific radioactivity of free cholesterol in the microsomal fraction prepared from the incubated tissue exceeded the specific radioactivities of free cholesterol in the other subcellular fractions. The estimated specific radioactivity of taurocholate formed during the incubation was far higher than that of microsomal free cholesterol. These data indicate that hepatic microsomal free cholesterol which was newly synthesized in situ was preferentially incorporated into cholic acid.     

A synthesis of array antennas for high directivity and low sidelobes

By application of a Gegenbauer polynomial, pattern synthesis of array antennas which have high directivity and low sidelobe level is investigated. A Chebyshev or uniform-amplitude array is included as a special case of the result obtained. The current amplitudes of the array elements are represented by a Jacobi polynomial and are easily calculated. It is shown by numerical calculations for a linear array and a hexagonal planar array that there is an optimum directivity for a specified sidelobe level within a class of Gegenbauer-polynomial patterns.     

Occurrence of plant sterols in aquatic vertebrates

Plant sterols were found by gas liquid chromatography in the sterols of five species of aquatic vertebrates; mackerel (Scomber japonicus), rainbow trout (Salmo gairdnerii), smelt (Osmerus dentex), sardine (Sardinops melanosticta) and chimera (Chimera phantasma). The sterols of chimera liver, sardine flesh and sardine viscera contained 9.0, 2.4 and 3.1% of C₂₈ and C₂₉ sterols in addition to 86.7, 96.6 and 95.2% of cholesterol. The occurrence of norcholestandienol, campesterol, β-sitosterol and C₂₈ stanol was shown by combined gas chromatography-mass spectrometry. Sperm whale (Physeter catodon) sterols consisted of more than 99% cholesterol with only traces of 22-dehydrocholesterol.     

Ionic graft copolymerization. I. Homopolymerization of β-propiolactone by sodium acetate catalyst

The polymerization of β-propiolactone (βPL) by sodium acetate catalyst has been investigated. The polymerization behavior with monomer purified with calcium chloride was found to be a little different from that previously reported for this monomer. That is, poly-β-propiolactone (PβPL) obtained from βPL dried with CaCl₂ has a higher degree of polymerization than that obtained from conventionally treated βPL, and its infrared spectrum shows type II configuration, which differs from that reported in previous papers. Some chain transfer reaction is observed even for the polymerization of the CaCl₂–dried βPL; however, this is less important in toluene. The electronegativity of the anion or cation in catalyst greatly influences the rate of polymerization.     

Enzyme-linked immunosorbent assay for monitoring toxic dioxin congeners in milk based on a newly generated monoclonal anti-dioxin antibody

To develop an enzyme-linked immunosorbent assay (ELISA) for monitoring the toxicity due to polychlorinated dibenzo-p-dioxins and dibenzofurans contaminated in human breast milk, we have generated novel monoclonal antibodies using some haptenic derivatives linked to bovine serum albumin via the C-1 or C-2 position on the dioxin skeleton. BALB/c or A/J mice were repeatedly immunized with the immunogen, and spleen cells were fused with P3/NS1/1-Ag4-1 myeloma cells. After five fusion experiments, a hybridoma clone was established that secretes an antibody D9-36 group specifically recognizing the major toxic congeners, 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), 1,2,3,7,8-pentachlorodibenzo-p-dioxin, and 2,3,4,7,8-pentachlorodibenzofran. An ELISA is developed on the basis of the competitive and labeled-antigen format. The toxic congeners extracted from butter or milk specimens by a novel extraction cartridge and a peroxidase-labeled dioxin analogue were sequentially reacted with a fixed amount of D9-36 in the presence of Triton X-100. The bound fraction was captured on a microtiter plate, immobilizing a second antibody, and the enzyme activity was colorimetrically determined. This ELISA afforded a practical sensitivity (measurable range, 1-100 pg/assay; detection limit, 1.0 pg/assay as 2,3,7,8-TCDD equivalent). The assay values for milk and butter samples were in reasonable accordance with the sum of the toxicity-equivalent quantity of each congener, which had been determined by a high-resolution gas chromatography/high-resolution mass spectrometry method.     

Specimen preparation for high-resolution transmission electron microscopy using focused ion beam and Ar ion milling

We have developed a focused ion beam (FIB)-Ar ion-milling technique for high-resolution transmission electron microscopy. A micrometresized specimen was mounted on a cross section of metal foil of a few micrometres thick, using FIB microsampling. Following this, a 2 degrees wedgeshaped part was made in the specimen using FIB. Finally, the specimen was milled using an Ar ion beam to remove the FIB-damaged layers. We applied the FIB-Ar ion milling technique to a CeO(2)/Gd(2)Zr(2)O(7) multilayer specimen, resulting in the crystal lattice fringes of both layers being clearly observable in comparison to a specimen finished using a Ga ion beam at an accelerating voltage of 10 kV.     

Polygonal epithelial cells in glomerular cell culture: Podocyte or parietal epithelial origin?

Podocytes are unique cells with regard to morphology, their inability to proliferate in situ, and their apparent essential function for glomerular filtration and permselectivity. Upon transfer into culture conditions, polygonal epithelial cells grow out from isolated glomeruli and these cells have been postulated to represent dedifferentiated podocytes, even though they are negative for podocyte-specific markers and undergo cell division. However, it is controversial whether they originate from podocytes or parietal epithelial cells (PECs) of Bowman's capsule, because isolated glomeruli contain more or less Bowman's capsule. In this review, we shall summarize recent progress in the identification of the origin of the polygonal cells and the characterization of podocytes in culture.     

Reactions of polymers in supercritical fluids for chemical recycling of waste plastics

Sub- or supercritical fluids have been focused as reaction media for environmental applications from a view point of green chemistry. Chemical recycling of waste plastics is important issue. We have applied reaction in water or organic solvent in sub- or supercritical condition to convert polymers into its monomers. Condensed polymers such as polyethylene terephthalate or nylon 6 were depolymerized to its monomers by hydrolysis of alcoholysis in supercritical water or alcohol. The other polymers such as phenol resin and fiber reinforced plastics (FRP) were also decomposed to small molecules by solvolysis. In this paper, the degradation of polymers studied in our group was reviewed.     

Photoluminescence properties of GaN with dislocations induced by plastic deformation

Fresh (a/3)[1120] dislocations on the (1100) prismatic plane were introduced into GaN bulk crystals by plastic deformation at 950–1000°C. In photoluminescence studies at 11 K, the near-band-edge (3.48 eV) luminescence intensity decreased remarkably in the deformed GaN, which was attributed to the introduction of high-density nonradiative recombination centers during plastic deformation. The yellow-band luminescence (2.22 eV) decreased due to plastic deformation, while several luminescence bands centered at 1.79, 1.92, and 2.4 eV developed. The dependence of PL features on deformation and annealing suggests that yellow luminescence is not related to the native structure of edge dislocations in GaN.