[Vibration syndrome among forestry workers. Subjective symptoms and diagnostic norm]

Three hundred fourteen male forestry workers using vibrating tools were analyzed to evaluate the relationship among 11 items of the special examinations for the diagnosis of vibration syndrome and the relationship between the items and 13 subjective symptoms. The following results were obtained: Age of the workers had the strongest relationship to the grip strength. However, it showed less strong relationship with other items, such as the threshold of pain sense and that of vibration sense, and the degree of Raynaud's phenomenon (number of fingers affected). Working time in years with vibrating tools showed statistically significant correlations with the threshold of pain sense, that of vibratory sense, and with the degree of Raynaud's phenomenon. The threshold of pain sense, that of vibratory sense, and the degree of Raynaud's phenomenon correlated with each other but not with the skin temperature nor the recovery time of blood flow in the finger nail-beds. The rise of pain threshold exhibited the strongest association with the subjective symptoms. Vibratory sense threshold at 250 Hz also showed similar association with the latter. The skin temperature and the recovery time of blood flow had no association with any complaints except for gastric disorders. The grip strength, only when extremely lowered, was associated with the rise of ratio of complaints, i.e. percentage of the number of workers who complain among all the workers. The age was associated in general with the decreased ratio of complaints except for muscle weakness in arms and forgetfulness.

Milbemycins, a new family of macrolide antibiotics. Studies on the biosynthesis of milbemycins alpha 2, alpha 4 and D using 13C labeled precursors

The biosynthetic origins of the carbon skeleton of milbemycins alpha 2, alpha 4 and D were studied. 13C Labeled antibiotics, milbemycins alpha 2, alpha 4 and D, were isolated from the culture broth of Streptomyces hygroscopicus subsp. aureolacrimosus strain Au-3 after feeding [1-13C]acetate, [1-13C]-propionate, [3-13C]propionate, [1-13C]isobutyrate, DL-[2-13C]valine and L-[methyl-13C]methionine, and 13C NMR spectra of the antibiotics thus obtained were measured. It was revealed that the carbon skeleton, except for carbon 25, of milbemycins alpha 2, alpha 4 and D are derived from seven acetate units and five propionate units. It was also shown that the methyl, ethyl and isopropyl groups at carbon 25 in milbemycins alpha 2, alpha 4 and D are derived from acetate, propionate and isobutyrate or DL-valine, respectively, and the methyl carbon of the methoxy group at carbon 5 in milbemycins alpha 2 and alpha 4 was enriched by L-[methyl-13C]methionine.

Task demands determine RT retinal location function

With 3 types of tasks RTs at 7 retinal locations were measured. These tasks were called CRT in which the subjects responded with one of the two keys according to whether the presented digits were odd or even, simple-but-watch condition in which they tried to see clearly the presented digit and then respond in the simple RT manner, and simple-and-quick condition in which they simply responded to the onset of the stimuli. As may be expected, in the latter condition the subjects produced retinal-location function curve which showed only a little degradation at the peripheral positions, while in the CRT condition they responded to the peripheral stimuli much more slowly than to the central ones. The RTs of the simple-but-watch condition fell in between; most subjects showed the responses much like the ones in the simple-and-quick condition, but some of them produced a retinal location function identical in shape (although reduced by approximately 250 msec.) to the one obtained in the CRT condition. This was interpreted to be a failure (for most of the subjects) to direct attention to those parts of the stimulus properties that conveyed information on pattern. These findings gave warning as to the uncritical adoption of a simple-RT paradigm to measure iconic duration.

Oxidation of acetylpolyamines by extracellular polyamine oxidase produced by Penicillium sp. No. PO-1

The oxidation of acetylpolyamines by an extracellular polyamine oxidase of Penicillium sp. No. PO-1 was investigated. The optimal pH value for oxidation of acetylpolyamines was 6.0. The purified enzyme oxidized spermidine, spermine, N1-acetylspermidine, N8-acetylspermidine, N1,8-diacetylspermidine, N1-acetylspermine and N1,12-diacetylspermine. The relative velocities for oxidation of acetylpolyamines were lower than those of spermidine and spermine. The Km values for oxidation of acetylpolyamines were higher than those of spermidine and spermine. The enzyme split N1-acetylspermidine and N8-acetylspermidine at the same position of the linkage as in spermidine oxidation. N1-Acetylspermine was changed to N1-acetylspermidine. This oxidation mechanism was different from that of rat liver polyamine oxidase. N1-Acetylspermine inhibited the oxidation of spermine. Putrescine, N8-acetylspermidine and N1,12-diacetylspermine also inhibited the N1-acetylspermidine oxidation by the enzyme.

Studies on macrocyclic lactone antibiotics. VI. Skeletal structure of copiamycin

Skeletal structure of copiamycin (1) (C54H95N3O17), a potent antifungal antibiotic, was determined from the physicochemical properties of this compound and of its degradation products. This compound consists of 32-membered polyhydroxy lactone ring, an alpha, beta-unsaturated ester group, as well as a side chain with a disubstituted guanidine moiety as its terminal. One of the hydroxyl groups (presumably at C-19) forms a hemiketal ring with the keto group at C-15, and another (at either C-21 or C-23) forms a hemiester with a malonic acid moiety.

[Subacute toxicity test of cefoperazone in beagle dogs with the intravenous administration for 3 months (author's transl)]

The subacute toxicity test of cefoperazone (CPZ) in Beagle dogs with the intravenous administration for 35 days has been reported from our laboratory. In the present experiments, the subacute toxicity test of CPZ in Beagle dogs was carried out for longer administration period than before. CPZ was given intravenously to each group (2 or 4 dogs) at dose level of 100 mg/kg/day, 200 mg/kg/day and 400 mg/kg/day respectively for 3 months. Cefazolin (CEZ) was used intravenously for positive control using 4 dogs at dose level of 200 mg/kg/day and physiological saline was given intravenously to 2 dogs for 3 months. 1) In Beagle dogs received high dose of CPZ, transient vomiting, salivation and diarrhea were observed immediately after the administration. 2) Signs of anemia, such as decrease of erythrocyte and value of hemoglobin and hematocrit, and increase of reticulocytes of the peripheral blood and in fragility of red cell associated with decrease of food intake, were observed in 2 female dogs given CPZ of 400 mg/kg/day. In only one of these dogs, a positive reaction of COOMBS' test was shown. The anemia recognized in these 2 dogs seems to be of hemolytic nature. 3) The weight of thymus was decreased in all of 4 dogs given CPZ at 400 mg/kg/day and in 2 out of 4 dogs given CPZ at 200 mg/kg/day, respectively. 4) Based on the fact that no abnormalities were found in dogs given CPZ at 200 mg/kg/day except a slight decrease of weight of thymus in some of them, the maximum safety dose of CPZ was thought to be 200 mg/kg/day.

[Subacute toxicity test of cefoperazone in beagle dogs with the intramuscular administration for 3 months (author's transl)]

The subacute toxicity test of cefoperazone (CPZ), a new cephalosporin antibiotic, was carried out in both sexes of Beagle dogs. CPZ was injected in Beagle dogs intramuscularly at dose levels of 500, 250 and 125 mg/kg/day for 3 months. The same amount of physiological saline was injected to control dogs intramuscularly for 3 months. The following results were obtained: 1) Sign of severe pain was shown immediately after injection in groups of CPZ at 500 and 250 mg/kg/day. In the same groups, the focal necrosis, hemorrhage, cell infiltration and fibrosis of muscles of injected site were noted microscopically. 2) In only one out of 6 dogs given CPZ at 500 mg/kg/day for 3 months, decrease of red blood cells and in values of hemoglobin and hematocrit an increase of reticulocytes in the peripheral blood were observed. In the same dog, splenomegaly and extramedullary hematopoiesis in the liver was found histopathologically, and in addition, the body weight and the food intake decreased during the administration period, associated with the development of anemia. 3) In dogs receiving up to 250 mg/kg/day, atrophy of the thymus was recognized at autopsy and slight decrease of cortical lymphocytes was seen histopathologically. 4) Based on these results, the maximum safety dose of CPZ was thought to be 125 mg/kg/day from the present experiment.

Effects of divalent cation ionophores on the neuron membrane of the crayfish

The effects of divalent cation ionophores, A23187 and X-537A, on the electrical membrane properties were investigated by using the soma membrane of the X-organ of the crayfish. They reduced the amplitude and maximum rate of rise of Ca-action potential in lower concentration. As the concentration increased, a reduction of membrane resistance and hyperpolarization occurred simultaneously. Further increase resulted in membrane depolarization with a further decrease in resistance. The threshold concentration of X537A was 100 times higher than that of A23187. These effects were reversible only when the application period was relatively short, while a longer application resulted in an incomplete reversibility or in no reversibility at all. The ionophore effect was facilitated in high Ca medium and diminished in low Ca medium. In Sr medium, the same effects on the resistance and the membrane potential were barely observable. TEA reduced the effects of A23187 but did not completely inhibit the effects. The Na-cation potential was also reduced by the higher concentration of the ionophore. From these results it is concluded that the divalent cation ionophores. A23187 and X537A, carry divalent cations, Ca ions in a physiological medium, into the neuron soma through the membrane and the consequent increase of the intracellular divalent cations induces K conductance increase and that higher concentration of the ionophore induces the increase in the conductance of the other ion species, such as Na.