The diagnostic specificity of a new method to detect obstructive jaundice by determination of lipoprotein X (LP-X) was tested in 144 patients with different kinds of hepatic diseases and compared with the usual chemical "obstructive jaundice specific" tests, such as bilirubin, SGOT, SGPT, alkaline phosphatase, LAP and gamma-GT. The LP-X test was performed by using all-in test kit LP-X Rapidophor" low-voltage electrophoresis of Immuno AG/Wien. The results were correlated with the histological classification of the liver biopsy specimen. In 82% of the histologically verified cases of obstructive jaundice the result of the LP-X test was positive, whilst in 98.5% of the histologically negative cases the result of the LP-X test was negative. Hence, this LP-X method proved superior to chemical methods in providing a clear-cut positive or negative answer to the presence of cholestasis. Furthermore, the LP-X test was suitable for long-term follow-up investigation of patients with obstructive jaundice.
The effect of the major metabolite of aspirin, namely salicylic acid, upon the pentose phosphate pathway (PPP) of normal and G6PD-deficient red cells has been studied. Salicylic acid was shown to inhibit this pathway in proportion to the amount present. At any concentration of this substance there was greater inhibition of the PPP in G6PD-deficient than in normal red cells.
After a 500 mus laser flash a 120 mus phase in the decay of delayed fluorescence is visible under a variety of circumstances in spinach chloroplasts and subchloroplast particles enriched in Photosystem II prepared by means of digitonin. The level of this phase is high in the case of inhibition of oxygen evolution at the donor side of Photosystem II. Comparison with the results of Babcock and Sauer (1975) Biochim. Bio-phys. Acta 376, 329-344, indicates that their EPR signal IIf which they suppose to be due to Z+, the oxidized first secondary donor of Photosystem II, is well correlated with a large amplitude of our 120 mus phase. We explain our 120 mus phase by the intrinsic back reaction of the excited reaction center in the presence of Z+, as predicted by Van Gorkom and Donze (1973) Photochem. Photobiol. 17, 333-342. The redox state of Z+ is dependent on the internal pH of the thylakoids. The results on the effect of pH in the mus region are compared with those obtained in the ms region.
Analysis of the problems with infection in a series of 104 reinterventions, enables one to accentuate the importance of infestation from intraperitoneal foci (70 p. 100 of the cases). Extra-peritoneal entry pathways are difficult to prove. Septicemia is found in one out of every three cases. In certain cases, preventive treatment of the extra-peritoneal entry pathways must be opposed to the effectiveness of the surgical act in the eradication of septic foci.
The influence of pH on the growth of transmissible gastroenteritis virus (TGEV) in adult pig thyroid cell culture, and on the stability of the virus was studied. At pH 7.2 and 100 fold higher than those at pH 8.0. The adsorption, penetration and uncoating steps of the viral replicative cycle were shown to be unaffected by pH variation. Synthesis of TGEV RNA during the first 12 hours post infection was found to be unaffected by pH variation between the range 6.5-8.0. After 12 hours breakdown of this RNA appeared to occur in cultures held at pH 7.2 and 8.0 but not at pH 6.5. When incubated at 37 degrees C for 24 hours the virus infectivity was found to be least affected by pH 6.5 but when kept at 4 degrees C for the same length of time, the virus infectivity remained constant between pH 5.0 and pH 8.0.
The kinetics of the pH-induced dissociation of the 3 X 10(6) mol wt hemoglobin from Lumbricus terrestris (the earthworm) have been studied in a light-scattering stopped-flow apparatus. The ligand dependent dissociation data were fit well by a simple sequential model. The data for CO and oxyhemoglobin are consistent with Hb12 leads to 2Hb6 leads to 12Hb. Methemoglobin at pH 7 appears to be hexameric and the dissociation is consistent with the model: Hb6 leads to 6Hb. In a sequential decay scheme for which light-scattering changes are monitored, the relative amounts of rapid and slow phase are determined by the rate constants as well as the molecular weights of intermediate species. Assignment of the hexameric intermediate is supported by an investigation of the sensitivity of the theoretical kinetic curves to the molecular weights of the intermediates. This assignment is further supported by the following: (1) the same model will fit the data for oxy- and CO-hemoglobin at all three temperatures (a 24-29-fold variation in rate constants), (2) evidence from electron microscopy shows hexameric forms, and (3) methemoglobin is apparently stable as a hexamer at pH 7. When CO replaces O2 as the ligand, the dissociation rate increases by a factor of four. The met is about 20 times faster than the initial oxyhemoglobin dissociation rate, but perhaps more relevant for comparing dissociation of the hexamer, the met rate was respectively 100 times and 500 times faster than that for the assumed hexameric forms of CO- and oxy-hemoglobin. The activation energies for the dodecamer to hexamer dissociation and for the dissociation of the hexamer to smaller forms were about 30 kcal/mol for oxy-, CO-, and methemoglobin.