Document 4vYYKG7gBk6bBb6qR3D88wgnV

rrt?:. * r. :-v-j -4 r-.t* \*J TS'iAiv*&P' 'i**v *.; /' .1 Tii' 1 "* T? n"?*. ? i ' '? /* - n / i%/ l*^' *"V .Ui -tf. f-JwejbtV '* ** '-' S* :'03XSAL la ay last report ic you I mentioned the ?;erk a!. ieh ,*>r* fn*i?or iaB wxn tnis laq/oravGry* ^.nis worj -t ,as h o t ? been nublished and the reprint is enclosed* It coix eXusIvely proved: 1* .Xlmt the Xiberaticu* of calcium from the bona also liberated letC, and th erefore &his 5ms added farther -proof of our.original conclusion that lead metabolism runs parallel utth calcium metabolisms* It ebowed'that the active pars-thyroid extract,'*iiov? easily obtained, is the most efficient method so far found to Xiberote lend from the bone* In fact it is so efficient .bat- as a routine method in a&* skilled hands it mi^ht involve some risk* 3* It mis clear that in our experiments so much lead v?as liberated oy. the first treatment that subsequent treats to^f.^^i.nInecrreeaase'd1' excretion of lead* ",s It is obvious thmt rtbifi last finding is of - considerable -Im port unoe in to.e tx*Gti tmont ox poxsouln^, qq.nl * - C t.uo* t* fore have studied this problem this- year as obviously t* ese find ltx^s .iiggesteti that --nxy a urx&ix j-n.rt of *e&u stored blood stre-: If lb la were true, then eliminating the lead in ifcie particular deposit of calcium &nd. replacing it by pure- calcium phosphate would free the patient from the danger of Into acute maaifestations of lead poisonlag. be have, therefore, studied the source of readily available calcium in the body. Readily Available Calcium in the Bones. let us first recall the anatomy cf the solid bone* It is composed of hard, douse shafts of calcium salts with the center filled by bone marrow in ^hich are Interspersed fia spicules of bone* I frequently observed that when our cats died-, after,having be-on do leaded, these spicules .. were,contiguous by their absence, and it therefore sssmod w s ih source cf calcium easily avail-. i&' ' *,iW ' ' able ft-r 'general body needs* Our studies -of this year have proved this ^pothesis correct* when & high calcium diet is given to- tui animal, calcium iu rapidly deposited in the spicules. *hen tt low calcium diet is -Ivon, the spicules rapidly disappear vMi the bard shafts of the boiio are apparently uiiaffooted. T-- is is an important new conception of a source of easily available calcium and therefore, as we have pre-_ vlously shown, of load, this explains many clinical facts of lead poisoning, fhe replacing of who shafts of bene goes on gradually, ana accounts for the clow, omtinacus excretion of lend over a period of tenths ana years* -3ut the sadQeu floodin-.; of V-'?e body by load with. resulting scute lead oya-iptoco would ;>e duo to its liberation frcra the zaore readily available deposits in the bony spicules* lu treating lead poix-tuilng eases it io relatively easy to mobilise the load in theto spicules and then to ?oplace G then by calciua uneonbeus 4. S.^Etr^G d by lead, Ihia explains the results obtained with !r* Hunter when the second attempt at doleadlag vras ineffective. ITeso findings are of iaeortanc to you for they ehcv?i 1. . fhe lead storage it i':o body tffc ieh is Itapor taut in producing -.-be acute lead poisoning, can be elirainated by proper treatment*. >1* i^ato js&nxfestatof acute .toad `cxsoumg &ppearing several years after load exposure should be avoided by proper early treatment. 5 " 5. If late acute &a*.ixestations of lead poisoning - -occur m a patient v;n -as oeou. previously thoroughly delesded* it is -probably fair to aoeum that - these man. ifesiatloiis are due to newly acquired lead* Other nor!:#:le tried, in & series of patients, to find the value of sodium thiosulphate in tho ireuimPBt*ox lead poisoning. In the sis patients studied vre t?f<re unable to determine u^y def inite Influence of'this drug on the excretion of .load* .e plan to do farther work along those lines, tut so far cur results have .not beeix e uc oarage lag with the use of this drug in out lead poiDoaiiij* &xoh other rlc has been bone on the control of calGiufti meiubollcit .** the body, end o.f uouroo this acre*iS the control of load* be have been able to def initely establish the ness fact that thyroid extract markedly increases the sale ions excretion to a level vrhlch ic higher than by any other method now be are therefor plan ning :->is -ext year to aeo what, its effect is on lead stored in- the body* bfc have done a gre&t deal cf wcr& on the mode of action of para-thorsiono and its efficiency iu mobilising the cal cium stores in the body, miS t?o have found that %hlie it in effective at first, it gradually laces its efficiency in creasing the level of calcium la the blood and the sure ant of calcium excretion* fe have alecs studied the effect cf thy- raid and para-thyre id on Inorganic salts other than caleiusa .. or load and have alts studied the calciuia antg phosphate t- obcXisra*&A8t?:'.&**$ 4|^^j^ews diseases*' 'the repairs, thae^ obcorva^ Lons ui'e not thoroavhiy ^ v.; a,' a - a%%y. recorded here as they are vert corsolieeted a*.d rill eoo2 be published in detail* ' they arc of value in regard to lend poisoning 1a Increasing our understanding of -nhsi regulates calcium metabolism, and what influences the body to deplete the storage house of c&ieiujs. fhc v;orJs of t* is neat year rill bo a continuation along similar linos. ffc wcrlc of the pant year will be recorded in : a series of about fourteen papers, s-ow being prepared for publication*