July 14, 1922] 



SCIENCE 



49 



term. The first of the series died on the four- 

 teenth day after parathyroidectomy probably 

 from a hemothorax. Three hundred and sev- 

 enty-five ee of almost pure blood were found 

 in the thoracic cavity of this animal at autopsy. 



Of the remaining two pregnant animals one 

 went into labor four days after parathyroid- 

 ectomy and gave birth to seven young. This 

 animal showed slight tetany symptoms twenty- 

 four hours after operation and again violent 

 tetany at the time of labor. Three days later 

 the consumption of an unusually large meal of 

 meat precipitated a tetanic convulsion involving 

 the diaphragm. Artificial respiration had to 

 be given. The tetany was soon controlled by 

 enemata and intravenous injections of Ringer's 

 solution. The animal was kept throughout the 

 puerperium on a moderate meat and bone diet. 

 Artificial feeding of the young was resorted to 

 in part. The latter contracted distemper, the 

 last two dying from the disease on the twenty- 

 sixth and twenty-eighth days after birth. The 

 mother is alive at the time of writing (ninety- 

 eighth day after parathyroidectomy). She has 

 received no injections since the fifty-first day. 



The other pregnant animal went into labor 

 on the day of the parathyi-oidectomy and 

 within twenty-four hours gave birth to nine 

 young. Her tetany attacks were unusually 

 severe and difficult to control. Several of her 

 young died. Others were given away. Un- 

 aided she raised four of her young to the stage 

 of weaning. The last intravenous injection was 

 given on the fifty-second day after parathjroid- 

 ectomy. She is alive at the time of writing 

 and in splendid physical condition (eighty- 

 seven days after operation). 



Our chief conclusions are as follows : 



1. By means of the intravenous injection of 

 Ringer's solution completely parathjrroidecto- 

 mized animals can not only be kept alive for 

 a prolonged period of time but if this treatment 

 is maintained for about forty days they are to 

 all purposes cured of their tetany. 



2. On the basis of further work we find that 

 normal Ringer's solution is better than Ca free 

 Ringer's solution in controlling parathyroid 

 tetany. 



3. The source of the poison responsible for 

 the tetany is of exogenous origin (particularly 



meat of the diet). One can precipitate an 

 almost fatal attack of tetany thirty-three days 

 after parathyroidectomy in two hours by feed- 

 ing an animal one half pound of meat, espe- 

 cially if the latter is not fresh. 



4. In addition to the intravenous injections 

 of Ringer's solution it is important to avoid 

 constipation by feeding bones and giving soap 

 suds enemata. 



5. Even pregnant dogs can be kept alive. 

 Instead of dying in tetany within seventy-two 

 hours after parathyroidectomy they can pass 

 through pregnancy, labor, and raise their 

 young. The control and cure of pregnant and 

 laetating bitches is, however, much more difii- 

 cult than in normal, non-pregnant animals. 



6. None of the adult animals which have 

 survived as long as seven months have shown 

 any signs indicative of myxedema although 

 both lobes of the thyroid gland were removed 

 at the time of the parathyi-oidectomy. They 

 are in excellent physical condition. The ad- 

 ministration by mouth of dessicated thyroid 

 gland in three gram doses every other day for 

 more than one month did not have the slightest 

 effect on their general condition and behavior. 



7. The young animals born of and raised by 

 parathyroidectomized mothers never showed 

 any symptoms even suggestive of tetany. 



Arno B. Lucehardt 

 Philip J. Rosenbloom 

 Hull Physiological Laboratory, 

 The University of Chicago 



INFLUENCE OF H-ION ON GROWTH OF 

 AZOTOBACTERi 



While studying the influence of the reaction 

 of the soil solution upon the Azotobacter flora 

 of soils,= it seemed desirable to ascertain the 

 influence of the reaction of culture media upon 

 pure cultures of these organisms. Several 

 strains of Azotobacter were isolated from dif- 

 ferent soils and grown in dextrose media of 

 different hydrogen-ion concentrations. The 

 maximum hydrogen-ion concentration permit- 

 ting growth was found to be Ph S.ff-e.O for all 



1 Contribution No. 49, Department of Bacteri- 

 ology, Kansas Agricultural Experiment Station. 



2 P. L. Gainey : Science, N. S. Vol. 48, pp. 

 139-140. 



