Addition Of KC1 Research Articles

Peroxidase Stability and Reactivation after Heat Treatment and Manothermosonication

ABSTRACTThe effect of several factors on the resistance of horseradish peroxidase (POX) to heat and manotbermosonication (MTS), the simultaneous application of heat and ultrasonic waves under pressure, has been studied. Reactivation after heat or MTS followed very similar patterns. Both heat and MTS inactivation of POX had a similar pH dependence. Addition of sucrose or glycerol to the treatment buffer resulted in more inactivation of POX by heat. MTS reversed these effects, especially after addition of glycerol. Addition of KC1 had a slightly protective effect against both heat and MTS treatments whereas addition of glucose increased the inactivation of POX by heat and MTS. Higher concentrations of POX were less sensitive to MTS. Both heat and MTS inactivation of POX appeared to result from a common mechanism.

TPR study of Al 2O 3- and SiO 2-supported CuCl 2 catalysts

The reduction and oxidation of Al 2O 3- and SiO 2-supported CuCl 2 has been re-investigated using TPR. The two peaks observed in the TPR profiles of dried samples are attributed to a two-step reduction of CuCL 2 as opposed to previous assignments in which they were attributed to two types of immobilized cupric species with different reducibilities. EPR measurements of an Al 2O 3-supported sample after programmed reduction up to a point between the two TPR peaks, confirm the absence of cupric species. TPR measurements carried out after sequential treatments in C 2H 4, air and HCl show that the cycle CuCl 2-CuCl-Cu 2OCl 2-CuCl 2 does not occur with either support because HCl reduces the oxychloride to CuCl. It is also shown that the formation of Cu 2OCl 2 from CuCl requires temperatures higher than 498 K on SiO 2, whereas it can be formed at room temperature on Al 2O 3. The addition of KC1 or LaCl 3 allows the reoxidation at 498 K of the reduced species on SiO 2.

ABNORMAL CHANGES IN SERS OF SALICYLIC ACID ADSORBED ON COLLOIDAL SILVER AFTER ADDING KC1

The abnormal changes in SERS of salicylic acid adsorbed on colloidal silver caused by adding KC1 are reported in this article. It was found that the SERS of some vibrational modes corresponsing to certain structures in salicylic acid were reduced rapidly. However, only the SERS intensity of v(-OH) vibration near 3436cm-1 incresed further because of KC1 addition. Also the influence of adding KC1 on SERS signals of a series of molecules including -COOH structure such as p-aminobenzoic acid, benzoic acid etc., were investigated. It was shown that Cl- could obviously weaken the SERS intensity of those molecules adsorbed on silver colloid. Both the phenomena have been discussed, and were compared with the case of pyriline. The results of transmission electron micriscopy observation and UV-visible spectral. experiments showed the agreement with the above conclusion.

Interaction ofStreptomyces felleus with bromoxynil during growth on laboratory media

Streptomyces felleus resistant to the herbicide bromoxynil (BX) took up 95 % of the initial amount of BX from the solid or liquid medium containing 100 μg of the herbicide per mL during a 5-d incubation. 50 % of the amount taken up was degraded and 45 % deposited in the cell (90 % in the cytoplasm, 10 % in the cell wall). A prolonged incubation time did not result in any further decrease of BX concentration. The addition of KC1 (the effect of NaCl was less pronounced) increased the affinity of BX for the cell wall and slowed down both the uptake and degradation of BX. Though P-14 was capable of growing at 5- to 10 times higher concentrations of BX in comparison with sensitiveStreptomyces strains, the herbicide caused its physiological (growth rate decrease, antibacterial antibiotic production, pigmentation, dehydrogenase activities), morphological and ultrastructural changes.

Factors influencing survival of mammalian cells exposed to hypothermia: II. Effects of various hypertonic media

Survival of Chinese hamster lung (V79) cells, exposed as a function of time to hypothermia in tissue culture, in isosmotic and various hypertonic media was measured using a colony assay. The mechanism of hypothermie cell killing is different above and below 7 °C in this cell line. Addition of NaCl or mannitol to increase the tonicity to 400 mOsm greatly decreased the survival at 10 °C while addition of KCl had no significant effect. When these experiments were repeated at 5 °C, addition of either NaCl, KCl, or mannitol was detrimental to long-term cell survival. Furthermore, addition of mannitol to the medium did not improve survival when cells were stored at 7 °C. Addition of KC1 at 5 or 10 °C or NaCl at 5 °C only affected the cells' ability to accumulate sublethal damage, while addition of mannitol at 5 or 10 °C affected both of the above and the cold sensitivity of the cells. Addition of NaCl at 10 °C only affected the latter. These experiments suggest that prevention of cell swelling by these conditions, while possibly necessary during clinical hypothermie organ storage, is detrimental to single cell survival at these temperatures.

The effect of nifedipine and verapamil on KC1-induced rhythmic contractions of guinea pig ureter in vitro.

Addition of KC1 (40 mM) produced rhythmic contractions of guinea-pig ureters in vitro which were unaffected by phentolamine, atropine or tetrodotoxin. KC1 failed to elicit rhythmic contractions of ureters incubated in a Krebs solution with no added Ca++; in these conditions the addition of CaC12 in concentrations of 1.5 mM, or higher, produced rhythmic contractions whose frequency, but not amplitude, was proportional to CaC12 concentration in the bathing medium. EDTA reduced the frequency of KC1-induced rhythmic contractions without affecting their amplitude. Nifedipine and verapamil reduced both the frequency and the amplitude of KC1-induced rhythmic contraction; verapamil was more effective than nifedipine in reducing their amplitude. Urethane reduced the amplitude without significantly affecting the frequency of KC1-induced rhythmic contractions. An increase in the extracellular Ca++ concentration reverted the suppressive effect of all drugs under study. These results suggest that an influx of Ca++ from the extracellular space is responsible for the initiation of KC1-induced rhythmic contractions and is involved in the mechanism(s) which regulates their frequency, but that a separate mechanism regulates their amplitude.

Effect of Ionic Presence on Chlorine Disinfection of Animal Viruses

Work by Scarpino in 1972 indicated that disinfection rates are affected by ionic presence. When disinfecting coxackievirus A9 with H0C1 at pH 6.0 in the presence of 0.05M KC1 the effect is to increase the disinfection rate 50 times. Disinfection of coxackievirus A9 at pH 10.0 shows that 0.05M KC1 increases the disinfection rate 10 times. This rate difference due to 0.05M KC1 between the two pH's may be due to the charge on the hypochlorite ion, the change of charge on the surface of the virion, or to a change in the chemical equilibrium of chlorine due to the pH. Studies with poliovirus 1 and 0.05M KC1 showed the same ion effect. When the disinfection of poliovirus 1 with hypochlorous acid (H0C1) was compared with the disinfection of E.coli, the E.coli was disinfected quicker than poliovirus 1. This relationship that viruses are more resistant than the fecal indicator organism E.coli is generally accepted. However, poliovirus 1 was more sensitive to hypochlorite ion (OCl−) than E. coli, when 0.05M KC1 was present in the buffer. Whereas the ion effect was present for coxsackievirus A9 and poliovirus 1, it was not present for E.coli. We have been pursuing this ion effect phenomenon using both chlorine and chloramines. To determine whether this ion effect was present with chloramines, similar tests were run using monochloramine (NH2C1) as the disinfectant. Again the effect held. That is, the presence of KC1 in the buffers increased the efficiency of the disinfectant. This ion-effect was dose dependent between 0.05M KC1 and 0.1M KC1, where the effect was greater with 0.1M KC1. The OCl− and NH2C1 studies were both run at pH 10.0 and at 5°C. Tests were then run to determine whether the effect held for dichloramine (NHC12) at pH 4.5. The ion-effect was present using dichloramine. However, the level of dichloramine dropped from 11.5 ppm to 6.5 ppm during the test. The chloramine loss may be due to the shift of equilibrium as represented by the following equation: With the formation of nitrogen tri-chloride (NC13) the ion-effect could be dissipated if the addition of KC1 was made at a different time. When the chlorine species was formed in the presence of KC1 the effect was present. When the KC1 was added to the already formed specie the effect was not present in the case of monochloramine and much reduced in the case of hypochlorous acid. Therefore, the time of the KC1 addition to the system was critical to the ion-effect phenomenon.

Efflux of GABA, glutamate and glutamine from the brain: A mass fragmentographic Study

GABA, glutamate (GL) and glutamine (GLN) were measured by a mass-fragmentographic method in Ringer solutions filling epidural cups of freely moving rats and in cortical cups of urethane anaesthetized rats. The presence of the dura and the administration of uretane (1 g/kg) did not modify the efflux of GABA from the cerebralcortex. However the release of GL was reduced by the presence of the dura and by the administration of the anesthetic. Intracerebroventricular administrations of aminooxyacetic acid increased the brain GABA levels and its efflux from the cerebral cortex without any modification of the blood GABA concentration. The addition of KC1 (50 mM) to the cortical cups was followed by a dramatic increase in the efflux of GABA and by a parallel decrease in the efflux of glutamate and glutamine. Opposite effects were observed in animals with intact dura. The results suggest that GABA and glutamate are released from cellular structures within the brain and that their release may be inversely correlated.

The oxygen affinity of concentrated human hemoglobin solutions and human blood.

The log P50 of normal human blood at 37 degrees C, PCO2 = 0, 21, 42, AND 57 MM Hg in the absence and in the presence of 2,3-DPG and ATP, has been determined in the pH range 7.0 to 7.6. Similar data have been obtained for human hemoglobin isotonic solutions at different protein concentrations in the presence of various amounts of each of the cofactors which are known to affect hemoglobin oxygen affinity in blood. It has been found that the addition of KC1, organic phosphates, magnesium ions, and CO2 confers to a 32% human hemoglobin solution the same oxygen affinity (over the entire physiological pH range) of whole blood. Thus there is no room for significant effects caused by some other unidentified molecules or ions.

Red Blood Cell Potassium as a Measure of Body Potassium in Thiazide-Treated Patients with Essential Hypertension

In 34 patients with essential hypertension, 25 males and 9 females, red blood cell potassium (KRBC), exchangeable potassium (KE), and serum potassium (Ks) were determined after 4 weeks of treatment with 75 mg of hydrochlorothiazide daily, without additional KC1 or potassium-sparing diuretics, and again after another 5 weeks’ treatment, during which period supplements of either 60 mmol KC1 or 100 mg spironolactone were given daily. After thiazide treatment, KRBC and KE values were lower than in normal individuals. In the women, KRBC and KE were significantly correlated. After addition of KC1 or spironolactone, significant increases in KRBC and KE were found, but no significant correlation between these changes. It is concluded that the changes in exchangeable potassium are accompanied by changes in red blood cell potassium, but that correlation between these parameters is not pronounced.

Diffusion of Ions Through Collodion Membranes Treated with Urethanes

Anselmino has shown that collodion membranes, made so as to permit a slow passage of thiocyanate ion, have a lowered permeability to this ion when the dialysis system is treated with urethane, and that after the “narcotized” membrane is washed for about an hour with water, the normal thiocyanate permeability is restored. This observation has been frequently used in connection with the thesis that narcotics produce their effects through changes in permeability. When the experiments were extended to the study of the Cl ion, however, similar but less convincing results were obtained; we have, therefore, felt that a more complete investigation of the problem was necessary. Collodion membranes were made as described by Anselmino, and 5 cc. of M/2 KSCN placed on one side, and distilled water on the other. Determinations of the amount of thiocyanate passing were made at 3, 6, … 15 minute intervals by the addition of ferric chloride and comparison with standards. The experiment was then repeated with M ethyl carbamate on both sides of the membrane, and the retardation of diffusion described by Anselmino was confirmed, even when the ionic strengths on both sides of the membrane were equalized by the addition of KC1. Propyl, butyl, iso-amyl, and phenyl carbamate produce a similar effect, the concentration required decreasing with the length of the carbon chain. On extending the investigation to the rates of diffusion of other ions, however, we found the rates to be quite unaffected by the presence of any of the carbamates, for chloride ion (silver precipitation determination), sulphate ion (Ba determination), nitrate ion (phenylsulphonic acid determination), iodide ion (S2O3 determination), permanganate ion, ferrocyanide and ferricyanide ions (FeCl3 determination), ferrous and ferric ions, and finally potassium ion (cobaltinitrite determination) all pass through the collodion membranes as rapidly in the presence of the carbamates as in their absence. It therefore seems that the effect of the narcotics is a specific one for thiocyanate ion, and does not have the general significance which has been attributed to it. Collodion membranes containing lecithin were then prepared, and when these were used in the same type of experiment we found the addition of the carbamates to cause an acceleration of the diffusion of thiocyanate ion, instead of an inhibition. This effect depends on the quantity of lecithin present in the membrane (Table I). The narcotics, however, produced no effect whatever on the diffusion of sulphate, permanganate, or ferricyanide ion through these lipoid-containing membranes, and again we seem to be dealing with some effect specific for the thiocyanate ion. In the case of collodion membranes containing varying amounts of lecithin, from 0.01 to 0.1 p.c. of lecithin per gm. of dry membrane, together with varying amounts of cholesterol, from 0.01 to 0.1 p.c. per gm. of dry membrane, the carbamates again produce an acceleration of the diffusion rate of thiocyanate, but the effect becomes less as the amount of cholesterol is increased. The passage of the other ions studied was not affected by the addition of the narcotics.

Salinity of the Medium and Its Effect on Respiration in the Sea‐Anemone

The effects of pure salts and increase of salinity of the medium on marine cells and organisms, with respect to respiratory activity and metabolism, have been reported by a number of observers. (Warburg, i908; Meyerhof, i9iI; Page, 1929: Chambers and Reznikoff, i925: Gustafsen, 1921; Hess, 1930; Brooks, i919.) However, the sea-anemone, Metridium marginatum, has not been studied by the most accurate methods. These animals, exposed to currents of sea-water of varying salt-content, or when at the mouths of rivers quite often brought into contact with fresh and brackish waters, should exhibit some response to such a changing environment. Bodine (1928) has pointed out that KCl is toxic for the larvae, embryos and eggs of Fundulus, and that NaCl and CaCl2 are also quite toxic, with mixtures of K and Ca ions showing some antagonistic ion action causing them to be less toxic for the eggs, but quite toxic for the larvae and embryos. Pantin (I93i) and Pantin and Weil (I93i) have shown the reactions and adaptations for a flatworm to fresh, brackish and sea-waters. In most of the organisms studied, it is indicated that an increase in the NaCl content causes an increase in the metabolism as measured by oxygen uptake, while the addition of KC1 will also cause increased metabolism. The addition of CaCl2 to the medium usually causes a return to the normal respiratory rates, indicating an antagonistic ion effect. Increase in the salinity of the medium would be expected to bring a rise in metabolic rate, even though possibly only a temporary one, probably due to the toxic effect of increased salinity and osmotic pressure. A number of experiments were conducted with small specimens of Metridium in the respiratory chamber of the Thunberg-Winterstein microrespirometer (Thunberg, 1905: Fenn, I927), the animal being allowed to remain in the apparatus while experimental runs were made with the natural seawater as the immersion medium, with dilute or concentrated sea-waters of known salinity (Page, I928; McCallum, I926), or with the sea-water replaced by solutions of pure salts, A large number of experiments could be run on the same organism, the animal being allowed to settle down and fasten itself to the bottom of the respirometer chamber and live there, and at the conclusion of a series of experiments the unnatural medium was replaced by sea-water allowed to run continuously over the organism.