Arima, Kei (University of Tokyo, Tokyo, Japan), and Tetuo Oka. Cyanide resistance in Achromobacter. I. Induced formation of cytochrome a(2) and its role in cyanide-resistant respiration. J. Bacteriol. 90:734-743. 1965.-By following the cytochrome concentrations during the growth cycle and under various conditions (aerobic, aerobic plus KCN, reduced aeration, anaerobic plus NaNO(3)) in Achromobacter strain D, a close relationship between the formation of cytochrome a(2) (and a(1)) and the difficulty of oxygen utilization was demonstrated. Cytochrome o, which was the only oxidase found in aerobic log-phase cells, was present in bacterial cells grown under various conditions; the amount present had no relation to the degree of cyanide resistance. On the other hand, cytochrome a(2) (and a(1)) was inducible, and a close relation was observed between the amount of cytochrome and resistance to cyanide. Spectrophotometric observations indicated that, among the cytochromes present in resistant cells, cytochrome a(2) could be oxidized most easily in the presence of cyanide and that cytochrome b(1) could be oxidized without the oxidation of cytochrome a(1). We concluded that cytochrome a(2) is a cyanide-resistant oxidase capable of catalyzing the oxidation of cytochromes in the presence of cyanide. Cytochrome a(2) is also resistant to azide, an inhibitor of cytochrome oxidase.

Journal Article↗

PubMed1965

Cyanide Resistance in Achromobacter II. Mechanism of Cyanide Resistance.

Oka, Tetuo (University of Tokyo, Tokyo, Japan), and Kei Arima. Cyanide resistance in Achromobacter. II. Mechanism of cyanide resistance. J. Bacteriol. 90:744-747. 1965.-Photochemical data showed that the only oxidase found in the cyanide-sensitive cells of Achromobacter was cytochrome o, and that cyanide-resistant cells contained at least two oxidases. The oxidase responsible for cyanide resistance was a pigment the CO compound of which had its absorption band at a wavelength longer than 580 mmu. In addition, kinetic data suggested that there were two oxidases having different affinities for cyanide. From the data presented, resistance to cyanide in Achromobacter strain D was attributed to the induced formation of cytochrome a(2), which has a very low affinity for cyanide. Several characteristics of cytochrome a(2) as a cytochrome oxidase are summarized.

Journal Article↗

PubMed1963

[Pathological studies on hyaline degeneration in the central artery of the splenic follicle in dogs].

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Animals↗

PubMedDate not supplied

Some aspects of mouse mammary gland development from maturity to early pregnancy.

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Aminobutyrates↗

PubMedDate not supplied

Histologic and biochemical alterations in experimental acute pancreatitis induced by supramaximal caerulein stimulation.

We studied the histologic and biochemical alterations in experimental acute pancreatitis induced by supramaximal caerulein stimulation in rats. All rats received 4 subcutaneous injections of various doses of caerulein (5-50 micrograms/kg body weight) at hourly intervals over 3 h, and 9 h after the first injection all animals were killed. Subcutaneous injections of 20 micrograms/kg body weight of caerulein induced a significant increase in serum amylase activity and histologic evidence of acute interstitial pancreatitis similar to those observed with the 50 micrograms/kg body weight dosage of caerulein. Therefore, a total of 4 subcutaneous injections of 20 micrograms/kg body weight of caerulein was chosen to study the time-course of structural and biochemical alterations in caerulein-induced acute pancreatitis. Serum amylase activity reached a maximal value of 10-fold increase over the basal values at 6 h, and then decreased gradually to normal values at 18 h after the first injection. Remarkable interstitial edema and cytoplasmic vacuoles in acinar cells were the earliest histologic alterations. Cellular infiltration was prominent at 9-12 h after the first injection. Although these histologic changes almost completely disappeared after 24 h, the reduction in the number of zymogen granules was still detectable by electron microscopic examination even after 7 days. DNA content in the pancreas showed no significant changes following the induction of acute pancreatitis, whereas a moderate to marked reduction in enzyme content persisted after 7 days. Within 14 days after the initiation of the injections, both structural and biochemical changes had completely disappeared.

Acute Disease↗

PubMedDate not supplied

Abnormal coronary flow reserve in a 13-year-old girl with an absent left circumflex coronary artery.

We measured the coronary flow reserve in a 13-year-old girl with the rare anomaly of an absent left circumflex coronary artery. Although the coronary flow volume of the right coronary artery was at the same level as that of the left anterior descending coronary artery, the coronary flow reserve of the patient's right coronary artery was depressed without stenotic lesion, and it was less than the level of -2 standard deviation (SD) of the right coronary artery preponderance cases.

Adolescent↗

PubMedDate not supplied

Evidence that endogenous 6-(ARG or LYS)-opioid peptides can interact with kappa-receptors as agonists.

Evidence is provided for the abilities of endogenous 6-(Arg or Lys)-opioid peptides to interact with kappa-receptors as agonists. Dynorphin-(1-17) and -(1-8), alpha- and beta-neo-endorphin, [Met5]-enkephalin-Arg6-Phe7 and des acetyl salmon endorphin I significantly inhibited the electrically-evoked contractions of rabbit vas deferens which had been shown to contain kappa-receptors exclusively, indicating that endogenous 6-(Arg or Lys)-opioid peptides could act on kappa-receptors as agonists. Additionally, the inhibition of contractions of rabbit vas deferens by 6-(Arg or Lys)-opioid peptides was antagonized more effectively by Mr 2266 which had a high affinity to both mu- and kappa-receptors, than naloxone which had a high affinity only to mu-receptors. This also suggested that 6-(Arg or Lys)-opioid peptides acted as kappa-receptor agonists. The rank order of the inhibitory potency of 6-(Arg or Lys)-opioid peptides against contractions of rabbit vas deferens was as follows: dynorphin-(1-17) greater than alpha-neo-endorphin greater than beta-neo-endorphin .=. dynorphin-(1-8) greater than des acetyl salmon endorphin I greater than [Met5]-enkephalin-Arg6-Phe7. Since other endogenous opioid peptides such as [Met5]- and [Leu5]-enkephalin and beta-endorphin have been shown not to act on kappa-receptors as agonist, data in the present study suggest that endogenous opioid peptides can be classified into two groups in terms of an ability to interact with kappa-receptors as an agonist.

Animals↗

PubMedDate not supplied

The fine structure of the spermatozoa of two species of Rhacophorus (arboreus, schlegelii). I. Phase-contrast microscope, scanning electron microscope, and cytochemical observations of the head piece.

Green tree frogs, Rhacophorus arboreus and Rhacophorus schlegelii, living on the main island of Japan have spermatozoa in the form of a counterclockwise corkscrew composed of about 20 coils arranged in the shape of a cone. A head piece coiled loosely and tightly 5-6 times each. It was composed of two subcoils, one outside and the other inside. The outside subcoils composed the nuclear head, and the inside coils the acrosome. Following the head piece, a middle piece which had a mitochondrial sheath coiled 1 1/2 times. A tail piece which followed the middle piece coiled 3-10 times irregularly in 5-6 microns width with a 20- to 30-microns straight tail in length. There was a crystalline composed of 500-600 microtubules which surrounded a pair of cilial structures in the tail piece. The tannic acid-aldehyde-osmium tetroxide fixation method produced excellent electron density and good electron conductivity for scanning electron microscope observations.

Animals↗