scholarly journals STUDIES ON THE PNEUMONIC EXUDATE

1922 ◽  
Vol 35 (2) ◽  
pp. 153-160 ◽  
Author(s):  
Robert N. Nye
Keyword(s):  
Acid Medium ◽  
Sharp Increase ◽  
Proteolytic Enzyme ◽  
Amino Nitrogen ◽  
Alkaline Media ◽  
Medium Ph ◽  
Gradual Rise ◽  
Cellular Suspension ◽  
Ph Range ◽  
Normal Lungs

1. Washed cellular suspensions of pneumonic lungs, previously preserved with chloroform and toluene, contain a protease or proteolytic ferment, derived chiefly from the leucocytes of the exudate. 2. This protease is able to convert horse fibrin to a non-coagulable split product. In a pH range of 4.0 to 8.0 the digestion is slight at the most acid end. With decrease in acidity there is a gradual rise in activity to pH 6.0, and then a sharp increase up to the maximum digestion at pH 8.0. Judging from the amino nitrogen determinations, the most complete splitting occurs at pH 7.0. The degree of autolysis occurring in the pneumonic lung cellular suspension controls suggests that the active enzyme is identical with that causing the digestion of the fibrin. 3. Washed cellular suspensions of normal lungs, previously preserved with chloroform and toluene, contain a proteolytic enzyme which is active in a moderately acid medium (pH 4.0) and essentially inactive in less acid, neutral, and slightly alkaline media.

Studies on growth and symbiotic nitrogen fixation of Rhizobium of Vigna radiata under stress conditions

1984 ◽  
Vol 102 (2) ◽  
pp. 399-404
Author(s):  
R. Rai ◽  
V. Prasad
Keyword(s):  
Nitrogen Fixation ◽  
Yeast Extract ◽  
Vigna Radiata ◽  
Symbiotic Nitrogen Fixation ◽  
Alkaline Media ◽  
Growth Behaviour ◽  
Soil Stress ◽  
Wide Ph Range ◽  
Yeast Extract Mannitol ◽  
Ph Range

SummaryOne fast-growing acid-producing Rhizobium strain 995 of Vigna radiata was screened for growth behaviour in acid, saline and alkaline media. It grew well in yeast-extract mannitol broth of wide pH range as well as varying concentrations of NaCl, Na2SO4 and MnCl2. Variation in nodulation and N2-fixation efficiency occurred on different varieties of green gram, while strain characteristics were not affected by soil stress.

Proton motive force as a function of the pH at which Methanobacterium bryantii is grown

1985 ◽  
Vol 31 (11) ◽  
pp. 1031-1034 ◽  
Author(s):  
G. Dennis Sprott ◽  
Sharon E. Bird ◽  
Ian J. McDonald
Keyword(s):  
Membrane Potential ◽  
Proton Motive Force ◽  
Motive Force ◽  
Ph Gradient ◽  
Alkaline Media ◽  
Cytoplasmic Ph ◽  
Acidic Media ◽  
Generation Times ◽  
Optimum Ph ◽  
Ph Range

Methanobacterium bryantii was grown on CO2 and H2 over a pH range between the extremes of 5.0 and 8.1. Generation times were shortest between pH 6.6 and 7.1. Cells grown at optimum pH had a proton motive force consisting predominantly of the membrane potential but those grown at nonoptimal pH generated a transmembrane pH gradient as well. This pH gradient was, however, insufficient to maintain a constant cytoplasmic pH during growth in very acidic or basic media. The results suggest that in acidic media growth may be limited by the cytoplasmic pH and that in alkaline media it may be limited by the cytoplasmic pH and (or) by the magnitude of the proton motive force.

Effects of parathyroid hormone on net proton flux from neonatal mouse calvariae

1987 ◽  
Vol 252 (4) ◽  
pp. F585-F589 ◽  
Author(s):  
D. A. Bushinsky
Keyword(s):  
Parathyroid Hormone ◽  
Chronic Exposure ◽  
Neonatal Mouse ◽  
Alkaline Media ◽  
Alkaline Ph ◽  
Calcium Efflux ◽  
Acute Metabolic Acidosis ◽  
Ph Range ◽  
And Control ◽  
Proton Buffering

Bone mineral buffers protons during acute metabolic acidosis; whether parathyroid hormone (PTH) augments proton buffering is controversial. To determine whether PTH augments proton buffering by bone, we cultured neonatal mouse calvariae with or without PTH (10(-8) M) for 3 h in medium that was physiologically acid (pH approximately 7.20), neutral (pH approximately 7.40), or alkaline (pH approximately 7.60). Over the entire pH range studied there was less influx of protons into calvariae treated with PTH than into control calvariae, indicating that PTH does not augment but instead inhibits proton buffering by bone. To determine whether chronic exposure to PTH is necessary to augment proton buffering, calvariae were incubated with PTH for 24 h before a 3-h culture. Calcium efflux from calvariae exposed to PTH (10(-8) M) for 24 h exceeded that of controls. When these same calvariae were recultured for 3 h in fresh medium, PTH-treated and control calvariae behaved similarly, with net efflux of protons into acid, neutral, and alkaline media. Regardless of whether PTH is added at the time of exposure to acid medium or 24 h before calvariae cultured with PTH do not buffer protons to a greater extent than controls.

Alkaloid Sequestration by Papaver somniferum Latex

1984 ◽  
Vol 39 (9-10) ◽  
pp. 876-881 ◽  
Author(s):  
B. C. Homeyer ◽  
Margaret F. Roberts
Keyword(s):  
Acid Medium ◽  
Considerable Increase ◽  
Papaver Somniferum ◽  
Sodium Vanadate ◽  
Medium Ph ◽  
Alkaloid Sequestration ◽  
Chlormadinone Acetate ◽  
Atpase Inhibitors

Abstract The 1000 x g organelles of Papaver somniferum latex have been shown to accumulate rapidly, large quantities of alkaloids (0.05- 1 mg/mg organelle protein), particularly morphine, thebaine, codeine and papaverine and have been found to exhibit a surprising degree of specificity for the accumulation of these alkaloids. The uptake of alkaloid is independent of temperature and does not show a requirement for ATP 10-3 ᴍ, Mg2+ 10-3 ᴍ, or KCl 10-3 ᴍ. It is unaffected by known ATPase inhibitors (chlormadinone acetate 2.5 × 10-5 ᴍ, N,N-dicyclohexylcarbo- diimide 5 × 10-4 ᴍ and sodium vanadate 10-4 ᴍ) but showed considerable increase in morphine accumulation in the presence of 4-chloromercumbenzoate 5 x 10-4 ᴍ, while N-methylmaleimide 5 × 10-4 ᴍ had no effect, and carbonylcyanide 4-(trifluoromethoxy)phenylhydrazone 5 × 10-4 ᴍ caused a reduction (ca. 30%) of morphine uptake. An acid medium, pH 4.5-5.5, also results in decreased morphine uptake.

Phosphato complexes of cobalt(III). I. General structural and hydrolytic properties

1968 ◽  
Vol 21 (1) ◽  
pp. 37 ◽  
Author(s):  
SF Lincoln ◽  
DR Stranks
Keyword(s):  
Infrared Spectra ◽  
Base Hydrolysis ◽  
Alkaline Media ◽  
Bond Rupture ◽  
Acidity Constant ◽  
Acidity Constants ◽  
Acid And Base ◽  
Ph Range ◽  
Hydrolysis Of ◽  
Tracer Experiments

Phosphorus-32 tracer experiments have demonstrated that the phosphato ligand in [Co en2PO4]0 [Co(NH3)4PO4]O, [CO(NH3)4OH2HPO4]+, and [Co en2OH2.HPO4]+ undergoes slow substitution in acid and alkaline media at 40-60� and that a reversible hydrolysis equilibrium is established from pH 3 to 11. Outside this pH range, acid and base hydrolysis of all these phosphato complexes to diaquo or dihydroxo complexes is complete. The infrared spectra of [Co en2PO4]0 and [Co(NH3)4PO4]0 are consistent with a bidentate phosphato structure and with a monodentate phosphato ligand in CO(NH3)5PO4 and probably [Co(NH3)4OH2HPO4]+I-. The bidentate and monodentate complexes may be rapidly and reversibly interconverted but significant concentrations of the bidentate complexes only persist in the range pH 5.5-7.5. P.m.r, studies have established the predominantly cis configuration of the aquophosphato complexes. These complexes exhibit four acidity constants, one due to the aquo ligand, and three due to the monodentate phosphato ligand. The bidentate [Co en2PO4]0 exhibits a single acidity constant above pH 2. The aquophosphato complexes undergo both acid and base hydrolysis entirely by Co-O bond rupture. Acid hydrolysis of [Co en2PO4]0 also proceeds entirely by Co-O bond rupture but at pH 6.8 and in 0.25M NaOH hydrolysis proceeds by 60-65% Co-O bond rupture and by 30-35% P-O bond rupture.

Caractéristiques de pectines de marcs de raisins provenant d'essais comparatifs de vinification en rouge

OENO One ◽  
1983 ◽  
Vol 17 (4) ◽  
pp. 269
Author(s):  
J. Mourgues ◽  
J. Courtoisier ◽  
T. Conte
Keyword(s):  
Acid Medium ◽  
Galacturonic Acid ◽  
Dry Weight ◽  
Hot Water ◽  
Medium Ph ◽  
Heat Treated ◽  
C 30

<p style="text-align: justify;">The pectins extracted in a hot acid medium (pH 1,4 at 70 °C for 4 hours) from Carignan pomace washed in hot water (75 °C, 30 mn) desceded and pipped stemmed are different according to the vinification methods. in traditional vinifica tion with crushed grapes, there are changes during the fermentation on skins (reduction in the arnount extracted and in the quality of the pectins). The pectin extract from marc of heat-treated vintage (5,4 % dry weight) contains 77 % galacturonic acid esterified to 52 %, with a jellying power of 63 ° JAKOVLIV or 31 0 SAG. Due to its poor jellying power, it is not possible to forsee and industrial recuperation from the pomace of this variety.</p>

scholarly journals THE COLONY MORPHOLOGY OF TUBERCLE BACILLI

1936 ◽  
Vol 63 (1) ◽  
pp. 95-108 ◽  
Author(s):  
Kenneth C. Smithburn
Keyword(s):  
Acid Medium ◽  
Alkaline Medium ◽  
Environmental Conditions ◽  
Culture Medium ◽  
Colony Morphology ◽  
Human Type ◽  
Large Numbers ◽  
Ph Range ◽  
Type Strains ◽  
Bovine Type

The colony topography of tubercle bacilli is significantly affected by altering the pH of the culture medium on which the organisms are grown. Under the conditions of these experiments, avian tubercle bacilli produce two variants, rough and smooth. The former are most numerous on the most acid medium used (pH 6.0); the smooth colonies are obtained over a broad range of pH. Three colonial variants of bovine and human tubercle bacilli are described. Both mammalian types produce greater numbers of rough colonies at pH 6.0. The bovine type strains produce greatest numbers of smooth colonies in the pH range 6.4 to 6.8, and intermediate colonies on alkaline medium. The human type strains produce greatest numbers of smooth colonies at pH 6.4 and large numbers of intermediate colonies at pH 6.8 and pH 7.2. Included among the avian and bovine strains studied are organisms of widely varying pathogenic properties. Virulent and attenuated strains of a given type produce similar colonial variants under similar environmental conditions.

scholarly journals N.m.r. and e.p.r. investigation of the interaction of copper(II) and glycyl-l-histidyl-l-lysine, a growth-modulating tripeptide from plasma

1983 ◽  
Vol 209 (2) ◽  
pp. 533-539 ◽  
Author(s):  
J P Laussac ◽  
R Haran ◽  
B Sarkar
Keyword(s):  
Structural Information ◽  
Line Broadening ◽  
Medium Ph ◽  
Superhyperfine Structure ◽  
Planar Configuration ◽  
Rapid Exchange ◽  
Square Planar ◽  
Major Species ◽  
Wide Ph Range ◽  
Ph Range

Interaction of Cu(II) and Gly-His-Lys, a growth-modulating tripeptide from plasma, was investigated by 13C- and 1H-n.m.r. and e.p.r. spectroscopy. The n.m.r. line-broadening was interpreted in terms of major and minor species formed as a function of pH. The results indicate that the n.m.r. line-broadening is due to the presence of minor species in rapid exchange and not due to the major species in solution, which has a large tau M. It is concluded that the technique of 13C- and 1H-n.m.r. line broadening, caused by paramagnetic Cu(II) ion, should be undertaken with caution, since the method may not be useful for obtaining structural information on the major species. The e.p.r. spectra over a wide pH range are almost entirely due to similarly co-ordinating species. Starting at pH 5.5, the narrowest absorption near 340 mT shows superhyperfine structure, which comes out sharply in the pH region 6.0-9.6. The spectra in this pH range showed the seven lines of nitrogen superhyperfine splitting, indicating clearly the co-ordination of three nitrogen atoms to Cu(II). The e.p.r. parameters in the medium pH range, A parallel = 19.5 mT and g parallel = 2.21, fit well with the contention that Cu(II) is ligated to Gly-His-Lys through one oxygen atom and three nitrogen atoms in a square-planar configuration.

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