Document npJNJLNzoedaX1MXEDXGZOQZm

tm nmmt or mm mM mu mm wmm ittd* mm ' at the ii4ssi5023$ts Mm& s> mmztm In as$r last report to yn I aenticned the work which 3r* Hunter was doing In this laboratory* this twrk has now boon paOilshod and the reprir* la enclosed* It eon* laeirely proved; lm fimt the liberation of a&lola fro the ton* also liberated leal, sad &refore this -ha# added farther proof of oar original canolas ion that lead metabolism rone parallel with ealeio metabolism* 8* it showed' Hi at the a#tire para-thyroid attract, now easily obtained., is the seat efficient Method so far fa and to liberate lead fro the bom* la fact It is @o efficient that as a routine method in an* skilled '-ends it aijdit Involve some risk* S* It was clear that)itt ear experiments so maoh lead was liberated by the first treatment that eubseuaent ' .X '* * j ^ treatments yielded ab increased excretion of load* It is obvious that this last finding is o^. considerable la* portease in the treatment of load poisoning and we there fore hare studied this probls this year as obviously V ese find Inge suggested that only a mall part of lead stored blood trees*, if this were then lisaiiaatlng the load in this particular deposit ef aleiocs and replacing it by pare calcium phosphate would free the patient from the danger of late acute manifestation# lead poison ing. 4# have, therefore, studied the source of readily available caleius in the body* Beadily available Callam iii the lone. Let as first recall the anatomy of the solid bone. It is composed of hard, dense shaft# of e&lctom alt# with the center filled by bene marrow in which are interspersed fine spicules of bone. I frequently observed that when our cats died, after having been dleaded, these spicule wore conspicuous by their absence, and it therefor# seemed possible that here % a;. ^#-4eouree of ealeiosj easily avail- i - /-' > able fe^^fiersl'ubody, Our studies of thie year , tfVX .r*' ^ have proved'Hh'i'^.-jlfypd'ili'esi# correct. h#n a high ealciom diet is given to- to* unia&X, calcium is rapidly deposited in the spicules., when a low calcium lit i& 'iven, the spicules rapidly disappear while the hard shafts of the bone are apparently unaffected* T- Is is an important new conception ef a source of easily available calcium and therefore, a we have pr-^ vioasly ;.hosii, of lead. This explain# mmiy e Union 1 fact# of lend nolnouiug. Ihe replacing of the hafts of bone goes on grad rally, and ucoomts for the slow, c-utiiaaou# excretion of lead over a period of saeuths and years. 3at the sadden floodlit;,? of the body by lead with result log acute lead symptoms woaM be due to- it liberation from the acre readily avuilabl deposit# la the bony epical#*. Xii treating load poisoning case It is relatively @&ey to mobilise the lead' ia these spicule and then, be replace / them by aleiaa unoontaffiiiwiiea % lead* fhi# explain the result obtained with Dr* Banter hen the second attempt at deleading was ineffective* fhetm fiating are- of Importance to you for they host 1. fhe lead storage in the body which is important in producing ihe acute lead poisoning, can be ellain* ated by proper treatment* &* l&pe -afei^ffeetatioue of acute lead pcleeniag^&p* ' 'pea. - ri"-h- g** year# after load exposure } should be s A'^TQidetf %" proper early treatment* 3* If late acute aaifeatatioas .of lead pciacaiiig occur in a patient ssh-o has been previously thoroughly deleaded, it is probably fair to assume that these man ifestations- are due to newly acquired lead* Other *orlu Vie tried, la a aerie of patient, to find the raise of sod turn thiosulphate ia the treatment- of lead poisoning* la the sir patient indie* we war unable to do terrain# ;.*y fiefini to influence of 'this drug on the excretion of lead. .* plan to do farther sserk a long these lines, ,-ut sc fax oar results have .not been encouragelug ith the as of thi drug in acute lead poisoning. Jluoh oilier ovit h&m been don on the control of calciM metabolism in the body,, and of ,:oare this means the control of lend* 4# have beeo ubl& to def initely establish the new fact Mbat thyroid atraei m&r&ecly increases the calcium soretIon to a level which iu hither %han by any other method no k,.cwxm 4 sr threfore plan ning this next year to sea what it effect Is mi le&& stored ia the body* fe have done a great deal of worfc on the mode of action of para-thermos uni Its efficiency in mobilising ' the cal cium store In the body* ani we have found that while it la effective at first, if gy&da&lly loses its efficiency in in# creasing the level of calcium in the blood and the mmmii of otic Ion excretion, Is have also stuaied the offeet of thy roid and para-t^^id on lmr$&ui.Q salts other thaw enleisua v' XeMti ^w4 huv^also studied the calcium and shoe ,> at metop,^i^0iil.t)etalt1i end in various diseases* fhe results of these observations are not thoroughly recorded here at they ore very complicated i>u& nlil ts-oon be oubliahed in detail* fhe.y are of value in regard to .lead poisoning in increasing our understandig of what regulates calcium metabolism, and Hat influences the body to deplete the storage- roue of calc ion* *he wcr& of this next year will be a continuation along similar lines, the orfc of the p&st year will be recorded In a series of about fourteen papers, now being prepared for publication*