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Japanese quail genetically selected on the basis of atherosclerosis susceptibility were tested for infection by Marek's disease herpesvirus (MDV). Viral DNA was detected in the atherosclerotic aortas of susceptible (SUS) quail by the technique of DNA hybridization. Southern blot analysis demonstrated that restriction mapping of aortic DNA was specific and different from that of MDV. Screening of quail embryos by dot-blot hybridization detected that MDV DNA existed in 100% of SUS quail tested. Resistant (RES) quail were a mixed population, with 16% of embryos resembling the SUS group. Functional MDV was not found by a number of methods including virus isolation, serological test, and exposure of sentinel chicks to SUS quail. These results suggest that the SUS quail possess a portion of the MDV genome in the germline, and the viral genes have been coselected by their susceptibility to cholesterol-induced atherosclerosis.

Noncemented autophor ceramic total hip arthroplasty (ACTHA) has been developed in recent years for treatment of advanced hip diseases. Bilateral ACTHAs were routinely performed in two operations at a four- to six-month interval. There have been no reported series of one-stage bilateral ACTHAs. In this retrospective study, the authors compared 20 patients who had bilateral one-stage ACTHAs with 15 patients who had similar bilateral arthroplasties in two stages. The study revealed no significant differences in estimated intraoperative blood loss, postoperative hemovac drainage, total amount of blood transfusion, intra- or postoperative complications, or postoperative functional results in the two groups. There was no difference in achieving prosthesis stability by interface bone growth, in spite of a significant difference in weight-bearing status during the immediate postoperative period. The one-stage bilateral procedure, however, offered advantages over two-stage bilateral procedures, including shorter length of hospital stay (18 days versus 27 days), shorter operative time (148 minutes versus 245 minutes), shorter period of disability (86 days versus 202 days), and reduced economic costs (about 10% less). There was no increase in the risk of morbidity or mortality in the one-stage bilateral group. In selected cases, one-stage bilateral ACTHA would be preferable.

External skeletal fixation has been proved to be an effective method in treating complex femoral shaft fracture in adult patients with multiple trauma, extensive soft tissue injury or vascular injury which need reconstructive procedures. This method has the advantages of less extensive surgical exposure, easy wound access, and early ambulation. Twenty-two cases of femoral shaft fracture, between the ages of 10 and 15, were treated with the Hoffmann external skeletal fixator in Chang Gung Memorial Hospital from 1981 to 1985. The average time for union and removal of fixator was 72 +/- 8 days (from 44 to 150 days). The average leg length discrepancy was 0.6 +/- 0.3 cm. There was no deep wound infection, nonunion, rotationary deformity in closed fracture. All patients regained their range of motion of knee within 3 months after removal of the Hoffmann apparatus. The advantages of simple technique, less extensive surgical exposure, early ambulation, easy nursing care, patient comfort and no significant complications make it a good alternative method for treatment of femoral shaft fracture in young teens.

Nineteen children, aged 3-15 years, with acute femoral neck fracture were treated. The follow-up period ranged from 2 years to 6 years, 9 months (avg. 54.8 +/- 14.5 months). The clinical and radiological assessments were carried out according to the assessment system of Ratliff. Undisplaced fractures and all intertrochanteric fractures were treated conservatively and displaced ones by reduction and multiple pinning. The outcomes reveal 14 (79%) with good results, 2 (10.5%), fair and 3 (15.8%), poor. Four hips (21%) developed avascular necrosis with 2 requiring secondary surgical procedures. Both of them also had leg length discrepancy. Another 3 hips (15.8%) developed coxa vara, one of them had mild leg length discrepancy.

SUMMARY: Pseudomonas putida LP, which grows on lipoate, NH4NO3 and mineral salts, converts most of the organic substrate to bisnor-lipoate (1,2-dithiolane-3-propanoic acid) and acetyl-CoA. D-, L-, or DL-lipoate serve equally well as carbon and sulphur sources. There was no growth on or bacterial oxidation of the chemically synthesized bisnor- or tetranor-(1,2-dithiolane-3-carboxylic acid) chain-shortened analogues, but these, as well as lipoate, could supply the sulphur needed for growth when acetate was provided as the sole source of carbon. The uptake of lipoate by the bacterium is very slow and non-inducible, while the uptake of acetate is faster than octanoate. The oxidation of octanoate is more rapid and extensive than that of lipoate. Levels of acyl-CoA synthetase are not affected by the source of carbon, but activities of isocitrate lyase and malate synthase are higher when the cells are grown in acetate, octanoate or lipoate and lower when glucose is the carbon source. The glyoxylate cycle is induced to facilitate utilization of acetyl-CoA derived from lipoate, which is also degraded to water-soluble catabolites that yield the much smaller amount of sulphur required for growth.

The stabilities of the 1:1 complexes of Mn 2+ , Cu 2+ , and Zn 2+ with lipoate and its chainshortened catabolites, viz., bisnorlipoate and tetranorlipoate, were studied by potentiometric titrations in water containing 50% dioxane ( I = 0.1, NaClO 4 ; 25 °C). A comparison of the stabilities of these complexes with those of simple carboxylates reveals that the catabolite complexes formed with Cu 2+ and Zn 2+ are more stable than expected from only the basicity of the carboxylate groups. This is evidence that chelates involving the disulfide group are formed. The stability of all Mn 2+ complexes is determined by the basicity of the carboxylate groups. The same pattern of stability holds for the mixed-ligand complexes formed by Cu 2+ or Zn 2+ , 2,2′-bipyridyl, and lipoate or one of its derivatives. It is evident that the disulfide group of the 1,2-dithiolane moiety can participate in the formation of binary and ternary complexes. The somewhat less-pronounced coordinating properties of the 1,2-dithiolane moiety compared with the tetrahydrothiophene moiety are discussed. It is apparent that the electron density at S(1) and S(2) in the dithiolane moiety of lipoate is not equivalent: S(1) is favored over S(2) in electrophilic reactions; possible biological implications are indicated.

A new method is described for determination of antitrypsin activity based on inhibition of trypsin solubilization of calcium caseinate in agar plates. The method was applied to analyze soybeans after graded heat treatments for their antitrypsin content. Biological determination of protein and energy values of the soybean samples showed direct correlation of these values with the destruction of antitrypsin as measured by the new method, using rainbow trout.

Publisher Summary This chapter describes the chromatographic and spectral properties of lipoic acid and its metabolites. The relative mobilities of metabolites of lipoic acid on paper and thin-layer chromatographies is presented in the chapter for several of the solvent systems that have proved most useful in separating lipoate derivatives; lipoamide and its disulfhydryl and thiolsulfinate forms are included, even though they have not been isolated from the excreta of mammals or culture filtrates of bacteria. Lipoic acid and its derivatives in which the disulfide bond is intact (including the thiolsulfinates, or monoxides) are readily visualized as dark spots on developed paper or thin-layer chromatograms under ultraviolet light; the disulfhydryl compounds do not absorb in the near ultraviolet and so are not detectable by this means. The disulfhydryl compounds react readily with the spray reagent of nitroferricyanide giving a transient red color; disulfide compounds react with nitroferricyanide only after spraying with cyanide, such as thiolsulfinates. Thiolsulfinate compounds can be detected by exposing chromatograms to hydrochloric acid fumes, followed quickly by spraying with a solution of 1% potassium iodide and 1% soluble starch. Both anion-exchange and gel filtration have proved useful as column chromatographic techniques for separating the catabolites of lipoic acid.

Two chain-shortened analogs of lipoic (1,2-dithiolane-3-pentanoic) acid, viz. bisnor-lipoic (1,2-dithiolane-3-propanoic) and tetranorlipoic (1,2-dithiolane-3-carboxylic) acids, have been chemically synthesized. The ir, uv, pmr, and mass spectroscopic properties and paper, thin-layer, and column chromatographic mobilities of lipoic acid and its analogs were investigated and are given.

Nutritional muscular dystrophy in the chick results from the simultaneous deficiency of vitamin E and cystine. Being a biological antioxidant, vitamin E might be functional in maintaining a proper redox state of the sulfur-containing amino acid in the proteins. The analyses of protein-bound sulfhydryls and disulfides at onset of muscular dystrophy in young chicks were carried out. The ratio of disulfide to sulfhydryls increased two- to three-fold in dystrophic muscle as compared to that in the control muscle proteins. Dystrophic and normal muscle proteins also were subjected to SDS-gel electrophoresis. Proteins of low molecular weight, supposedly derived from proteolysis, were present in the gels of the dystrophic muscle and absent in those of normal muscle extracts. As a result of these studies, a chemical model has been proposed to explain the oxidative deterioration of proteins in nutritional muscular dystrophy due to vitamin E deficiency.

A selenium deficiency in chicks produces degeneration and fibrosis of the pancreas. An investigation was undertaken to determine whether or not the activity of lipoic acid is impaired in the pancreas of selenium-deficient chicks. Enzymatic analyses of selenium-deficient chick tissues showed a reduction in lipoamide dehydrogenase both in pancreas and liver at a very early stage of growth. Using both direct measurements and sucrose-gradient cellular fractionation, it was found that the lipoamide dehydrogenase activity of the supernatant increased, and that of the mitochondria decreased in selenium-deficient as compared to normal chick livers. These results indicate an increased fragility of the mitochondrial membranes in selenium-deficient chicks.

Femoral shaft fractures often happen, and usually indicate only one part of the traumatic injuries sustained by the body. Preoperative evaluation and management may be life-saving. The favored treatment of fracture itself is now intramedullary nailing. There were 144 adult cases treated with intramedullary nails and followed up for at least two years at Chang Gung Memorial Hospital from July 1981 to June 1984. The results revealed a high union rate 96.5% (139/144): closed method 100% (34/34), open method 95% (105/110). Significant complications requiring repeated annoying surgical reintervention were rare, only 4% (6/144), due to deep infection or nonunion. Bone union period was about four months. Range of motion of knee was also satisfactory. This study suggests enough benefit of the delayed closed intramedullary nailing in the management of femoral shaft fractures.

Two lines of Japanese quail were genetically selected. One is highly susceptible (SUS) to atherosclerosis, developing severe aortic atherosclerosis in 9 weeks by feeding 0.5% cholesterol in the diet. The other is highly resistant (RES), developing little disease under the same conditions. The pathology of quail atherosclerosis, characterized by intimal thickening, the presence of foam cells, the proliferation of myofibroblast cells, and the formation of scar with collagen deposition, is similar to the human disease. Because of its small size, low feed consumption, and short life cycle, these quail are an excellent model for the study for prevention and pathogenesis of atherosclerosis. A study has shown that the quail respond to treatment with nicotinic acid, gemfibrozil, clofibrate, and aspirin with reduction of atherosclerosis. More recently these birds were tested for the presence of a herpes virus, Marek disease virus (MDV), as a possible etiologic agent. Initial diagnosis by isolation of MDV and agar precipitin test was negative. However, when a gene library of MDV was used to prepare a battery of radioactive DNA probes, high-stringency DNA hybridization has demonstrated the presence of viral genes in quail aorta, heart, nucleated RBC, and embryo. The intensity of hybridization increased with the increased severity of atherosclerosis in aortas. In embryos, all SUS quail were positive, but only a part of RES quail were positive. These results indicated that these quail were latently infected by a putative herpes virus closely related to MDV. Since DNA homology was detected in the embryo, it is possible that the viral genes are integrated in the host DNA, and they are the heritable elements for the susceptibility to atherosclerosis.

A strain of bacteria that can degrade lipoic acid was isolated from soil. The bacterium, adapted to use 0.4% dl -lipoate as the sole organic substrate to supply carbon, sulfur, and energy, was identified morphologically and physiologically as a strain of Pseudomonas putida . Degradation of 1,6 - 14 C -lipoic acid, synthesized from 1,6 - 14 C -adipic acid, was evidenced by: (i) loss of approximately 50% of the total radioactivity from the medium after bacterial growth; (ii) appearance of 14 C-degradation products upon paper and thin-layer chromatography of the culture medium; and (iii) oxygraphically measured utilization of O 2 by cells in the presence of lipoate or other oxidizable substrates. Analyses of the benzene extract of culture medium by infrared, nuclear magnetic resonance, and mass spectrometry, and by gas-liquid chromatography after desulfuration, have characterized bisnorlipoic acid, or 4,6-dithiohexanoic acid, as the major catabolite present in the medium. β-Oxidation of the side chain is thus proven to be a pathway employed by the pseudomonad to degrade lipoic acid.

The microstructure of fiber-like SiC/Si3N4 composite particulate was investigated using high-resolution transmission electron microscopy techniques. The SiC/Si3N4 composite particulate consisted of aβ-SiC core and a α-Si3N4 outer shell. Two kinds of composite particulate were distinguished when the observed orientation of the SiC core was . In one type of the SiC/Si3N4 composite particulate, a crystal relationship of (111)β-SiC | (102) α-Si3N4 and (111)β-SiC ‖ (114) α-Si3N4 was identified; in the other type of the SiC/Si3N4 composite particulate, a crystal relationship of (111)β-SiC ‖ (001) α-Si3N4, and (111)β-SiC ‖ (101) α-Si3N4 was observed.

Following a discussion of existing probe theories for a collisional plasma, a new theory is given for ion collection by a spherical probe in a collisional plasma which goes over to the collisionless theory of Allen et al. at low pressures and the continuum theory of Su and Lam at high pressures. Numerical results are given in a form suitable for interpretation of experimental data. Experimental probe studies in the positive column (1 cm diameter) of a He discharge in the pressure range 0.05‐0.4 Torr are described and the use of the electron and ion saturation methods for determining plasma concentration compared with one another and with a microwave cavity perturbation method. The limitations of the theories and experimental methods are discussed.