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A History of Diabetes Mellitus: From Tasng to Tesng Produced by the Instute of Biomedical Science History Commiee Alchemy to Chemistry A Taste of Honey Polyuria, a common, but not specific symptom of diabetes, recorded in Egypan papyrus dated 1552 BCE and may represent earliest record of diabetes. Archaeological claims changes in human skeleton from Egypt (2055-1650 BCE) indicave of type 2 diabetes. Sushruta (c 500 BCE) Indian physician, described sweet taste of diabec urine he termed ‘madhumeha’ or honey urine, common pracce to taste urine if diabetes suspected. Also observed ants aracted to urine of diabecs, may sll be used for diagnosis in Africa. He described two different forms of presentaon, younger thinner paents and older and more obese paents who lived longer. Copper Reducon Many sugars, including glucose, have reducing properes, exploited by progressive colour changes during reducon of blue copper sulphate soluons to green, yellow to brown/red with increasing amounts of sugar. 1841 Karl Trommer (1806-1879), German chemist first devised a copper reducon test, more stable copper sulphate reagent by Hermann von Fehling (1812-1885) in 1850. Sensive copper reagent described in 1908 by Stanley Benedict (1884-1936) with further modificaon two years mainstay of urine monitoring of diabetes for over fiſty years. 1945 Ames developed Clinitest, a more convenient solid tablet form of copper reducon and Clinisx, a dip and read specific reagent strip for urine glucose developed by Ames research team led by Albert & Helen Free in 1957. Why Diabetes Mellitus? Aretaeus (130-200 CE) gave more detailed descripon of symptoms, notably excessive thirst, weight loss as a ‘melng down of flesh and limbs’ into urine. He named diabetes from Greek ‘siphon’ and ‘flowing out’. In 1778 William Cullen (1710-1790) added mellitus (Greek for honey) for sweetness of urine of diabecs. Searching for the Cause Polyuria with glycosuria key features of diabetes in early 19th century, the cause remained elusive. Claude Bernard (1813-1878) in 1846 showed sugar absorbed from intesne converted to glycogen in liver for release into blood as required. Various theories raised that diabetes was due to infecon or originated in the liver, brain or nervous system. Tasng and Tesng (500CE unl 17thC) Urine collected into special glass flask, a matula, examined by ‘physick’ for volume, colour, clarity, sediment, odour and taste for predicve ‘diagnosis’ of wide range of diseases. The sweetness of the urine of diabecs recognised in India, China, Africa and Persia, but not recorded in Europe unl the 17th century. Paracelsus (1493-1541) suggested chemical analysis of urine and obtained white residue on evaporaon he believed salt and proposed the cause of diabetes was deposion of salt affecng kidneys and stomach. Brish physician Thomas Willis (1621-1675) regarded diabetes as the ‘pissing evil’ and wrote trease on urinalysis, his observaons on diabetes recorded in ‘Pharmaceuce raonalis’ (1674). He described the urine as ‘exceedingly sweet’ and ‘wonderfully sweet like sugar or honey’! 1772 Mahew Dobson (1735-1784) showed sugar like substance present in urine and blood of a diabec paent. He found that evaporaon of urine leſt a residue which tasted like brown sugar and serum also tasted sweet. 1780 Francis Home (1719-1813) demonstrated that urine containing sugar undergoes fermentaon with yeast. 1815 Michel-Eugene Chevreul (1786-1889) French organic chemist demonstrated sugar present idencal to grape sugar (glucose). 1862 William Roberts (1830-1899) adapted fermentaon test using urinometer to measure the change in specific gravity on fermentaon which related to concentraon of urine glucose. Used by physicians, notably Frederick Pavy (1829-1911) of Guy’s Hospital, to study effect of dietary variaon. Claude Bernard (1813-1878) Helen Free Stanley Benedict (1884-1936) Physick examining matula

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A History of Diabetes Mellitus: From Tasting to TestingProduced by the Institute of Biomedical Science History Committee

Alchemy to Chemistry

A Taste of Honey• Polyuria,acommon,butnotspecificsymptom

ofdiabetes,recordedinEgyptianpapyrusdated1552BCEandmayrepresentearliestrecordofdiabetes.

• ArchaeologicalclaimschangesinhumanskeletonfromEgypt(2055-1650BCE)indicativeoftype2diabetes.

• Sushruta(c500BCE)Indianphysician,describedsweettasteofdiabeticurinehetermed‘madhumeha’orhoneyurine,commonpracticetotasteurineifdiabetessuspected.Alsoobservedantsattractedtourineofdiabetics,maystillbeusedfordiagnosisinAfrica.Hedescribedtwodifferentformsofpresentation,youngerthinnerpatientsandolderandmoreobesepatientswholivedlonger.

Copper Reduction• Manysugars,includingglucose,havereducingproperties,exploitedbyprogressivecolourchanges duringreductionofbluecoppersulphatesolutionstogreen,yellowtobrown/redwithincreasing

amountsofsugar.

• 1841Karl Trommer (1806-1879),Germanchemistfirstdevisedacopperreductiontest,morestablecoppersulphatereagentbyHermann von Fehling (1812-1885)in1850.

• Sensitivecopperreagentdescribedin1908byStanley Benedict (1884-1936)withfurthermodificationtwoyearsmainstayofurinemonitoringofdiabetesforoverfiftyyears.1945AmesdevelopedClinitest,amoreconvenientsolidtabletformofcopperreductionandClinistix,adipandreadspecificreagentstripforurineglucosedevelopedbyAmesresearchteamledbyAlbert & Helen Freein1957.

Why Diabetes Mellitus?• Aretaeus (130-200 CE)gavemoredetailed

descriptionofsymptoms,notablyexcessivethirst,weightlossasa‘meltingdownoffleshandlimbs’intourine.HenameddiabetesfromGreek‘siphon’and‘flowingout’.

• In1778William Cullen (1710-1790)addedmellitus (Greekforhoney)forsweetnessofurineofdiabetics.

Searching for the Cause• Polyuriawithglycosuriakeyfeaturesofdiabetesinearly19thcentury,thecauseremainedelusive.

ClaudeBernard(1813-1878)in1846showedsugarabsorbedfromintestineconvertedtoglycogeninliverforreleaseintobloodasrequired.Varioustheoriesraisedthatdiabeteswasduetoinfectionororiginatedintheliver,brainornervoussystem.

Tasting and Testing (500CE until 17thC)• Urinecollectedintospecialglassflask,amatula,examinedby‘physick’forvolume,colour,clarity,

sediment,odourandtasteforpredictive‘diagnosis’ofwiderangeofdiseases.

• ThesweetnessoftheurineofdiabeticsrecognisedinIndia,China,AfricaandPersia,butnotrecordedinEuropeuntilthe17thcentury.Paracelsus (1493-1541)suggestedchemicalanalysisofurineandobtainedwhiteresidueonevaporationhebelievedsaltandproposedthecauseofdiabeteswasdepositionofsaltaffectingkidneysandstomach.

• BritishphysicianThomas Willis (1621-1675) regardeddiabetesasthe‘pissingevil’andwrotetreatiseonurinalysis,hisobservationsondiabetesrecordedin‘Pharmaceuticerationalis’(1674).Hedescribedtheurineas‘exceedinglysweet’and‘wonderfullysweetlikesugarorhoney’!

• 1772Matthew Dobson (1735-1784)showedsugarlikesubstancepresentinurineandbloodofadiabeticpatient.Hefoundthatevaporationofurineleftaresiduewhichtastedlikebrownsugarandserumalsotastedsweet.

• 1780Francis Home (1719-1813)demonstratedthaturinecontainingsugarundergoesfermentationwithyeast.

• 1815Michel-Eugene Chevreul (1786-1889)Frenchorganicchemistdemonstratedsugarpresentidenticaltograpesugar(glucose).

• 1862William Roberts (1830-1899)adaptedfermentationtestusingurinometertomeasurethechangeinspecificgravityonfermentationwhichrelatedtoconcentrationofurineglucose.Usedbyphysicians,notablyFrederickPavy(1829-1911)ofGuy’sHospital,tostudyeffectofdietaryvariation.

Claude Bernard (1813-1878)

Helen Free Stanley Benedict (1884-1936)

Physick examining matula

A History of Diabetes Mellitus: From Tasting to TestingProduced by the Institute of Biomedical Science History Committee

Islets to Insulin

Charles Herbert Best (1899-1978) & Frederick Banting (1891-1941)

Frederick Banting (1891-1941)

Dietary Control & Quack Remedies For Diabetes• 1792-96BritisharmysurgeonJohn Rollo (d

1809)reducedglycosuriawithhighmeat,lowgrainsandbreaddiet.Branmuffinsandalmondbiscuitsweregivenasbreadsubstitutesin19thcentury.Faddietsearly20thcenturyincludepotato,oatmealcureandquackremediesegvinuranepesqui,Dillsdiabeticmixturecontainedbromides,opium,arsenic,uraniumnitrateofteninalcohol.

• 1912Frederick Allen (1876-1964)completedstudiesofglycosuriaanddiabetestointroducecaloriecontrolleddiet,commonlycalleda‘starvation’diet.However,despiteprolonginglifeexpectancy,patientsdangerouslyunderweight,physicallyweakandoftenregressedintocoma.

• Elliot Joslin (1869-1962)specialistindiabetesbecamepioneerinpromotingglucoseregulation,patientselfmanagementandeducation.TodaythereareJoslinDiabetesCentresacrossUSAandCanada.

Pancreatic Extracts• Treatmentwiththyroidextractinmyxoedemain1891byEnglishphysicianGeorge Murray (1865-1939)

raisedpotentialofpancreaticextractsindiabetes.Potentialdifficultiespurityofbetacellsofisletswhichconstituteonly1%ofthepancreas,minimisingdigestiveenzymeaction.

• 1899Leonid Sobolev (1876-1919)suggestedligationofpancreaticductisolatesisletcellstoprovideextractsuitablefortreatment.Between1900&1921atleast5researchgroupsattemptedunsuccessfullytoobtainsafeandeffectiveextract.Impuritiescausedseveresideeffectsandvariationin‘batch’potencycouldproduceextremehypoglycaemicepisodes.

Insulin: A Medical Miracle • 1920Frederick Grant Banting (1891-1941),

beganresearchworkatUniversityofTorontounderJohn JR Macleod (1876-1935).BantingrealisedfromearlierobservationsofSobolevandMoses Barronin1919thatprolongedligationofpancreaticductwoulddestroyacinarcellsbutnotaffectisletcellsbelievedtocontainpancreatichormone‘insuline’(Latin-insula-island),asnamedbySharpey-Shafferin1916.

• BantingandCharles Herbert Best (1899-1978)usinglaboratorydogs,excisedpancreasandpreparedextractsinjectedintodepancreatiseddogs.BestskilledinbloodsugarmicromethoddevelopedbyRC Lewis and Stanley Benedictin1913onlyrequired0.2mlblood,foundextractsloweredbloodsugarandurinewassugarfreewithphysicalandclinicalimprovement.Similarresultsobtainedfromextractsoffreshfoetalcalfandadultbeefpancreas.

• James Bertram Collip (1892-1965)joinedresearchinlate1921tohelpimprovequalityandpurityofextracts,assessmentofpotencywithmeasurementofbloodsugarofrabbits.Alsofoundthatdailyadministrationofextractcouldextendthelifeofdiabeticdogs.

• FirstrecordeduseofinsulinonhumansJanuary1922;apancreaticextractpreparedbyBestgiventoa14-year-oldboywithseverediabetes,withafallinbloodsugar.Repeated12dayslaterwithextractpreparedbyCollipwithevenmoresignificantreductioninbloodsugar.

The Pancreas: A Hidden Organ• 100ADRepos,Greekanatomist,named

pancreas(panall,kreas flesh)littleknownoffunction;believedprotective‘cushion’formajorbloodvesselsandnerves.

• 1689Johann Brunner (1653-1727)inducedtemporarysymptomsofextremethirstandpolyuriaindogswithoutpancreas.

• 1788Thomas Cawleyobservedpancreatictissuedamageinautopsyofpatientwithdiabetes,suggestedanassociation.

• However,mostattentiongiventoexocrineroleofpancreasindigestionuntil19thcentury

The ‘Active’ Principle• ConceptofinternalsecretionbyglandsCharles Edouard Brown Sequard (1817-1893)appliedtodiabetes

byEdward Sharpey -Shaffer (1850-1935)in1895.

• Exactly200yearsafterBrunnerstudies,Oskar Minkowski (1858-1931)andJosef von Mering (1849-1908)inducedseverediabetesafterremovingpancreasindogsandGustave Laguesse (1861-1927) suggestedin1893that‘internalsecretion’producedbyisletsofirregularpolygonalcellsfirstdescribedbyPaul Langerhans (1847-1888)in1869.

• 1901Eugene Opie (1873-1971)proposedantidiabeticsubstancepresentinisletcellsalteredindiabetes.InnextyearErnest Starling (1866-1927)andWilliam Bayliss (1860-1924)introducedconceptofhormonesaschemicalmessengerstransmittedbybloodinseminalstudiesofsecretinandpancreaticsecretion.

Frederick Allen (1876 -1964)

Elliot Joslin (1869-1962)

A History of Diabetes Mellitus: From Tasting to TestingProduced by the Institute of Biomedical Science History Committee

Insulin - A Therapeutic Miracle

Early Experience • 1922Largescaleproductionofhighquality

insulinwithcollaborationofEliLilly

• 1923BritishmedicalresearchcouncilacceptspatentrightsandwithdrugcompaniesinsulinavailableinUKhospitals

• 1926John Abel (1857-1938)preparedcrystallineinsulin,10,20,40units/mlavailableworldwide

Living on the Edge• Variationininsulinquality,personal

requirementsandpoorassessmentoftreatmentwithsustainedperiodsofuncertainty,fearfulofhypoglycaemiaandhyperglycaemia.Onlyeffectivebyinjectionandrequiredlifelonginseverecases.

• Lifeexpectancyofseverediabeticsextendedbutgreaterawarenessofcomplicationsandlessemphasisonstrictdiets.

• 1934BritishDiabeticAssociationfounded,twoyearslaterHarold Himsworth (1905-1993)BritishphysicianconfirmedearlierworkofWilhelm Falta (1875-1950)toidentifytwoformsofdiabetes-insulinsensitiveorthoseinsensitiveorresistant.

Different Types of Insulin from 1936• Toavoidinjectionspremealsandduringthe

night,longeractinginsulindevelopedatNordisklaboratories,Copenhagenunderdirectionof

Hans Christian Hagedorn (1888-1971).

• 1936Insulincombinedwithprotaminetoreleaseinsulinover6-8hours.ProtamineZincInsulin(PZI)developedatTorontoUniversityinsameyear,effectivefor24hoursbuttendencytohypoglycaemia.

• 1940NeutralProtamineHagedorn(NPH)orIsophaneavailableandLenteseriesdevelopedbyNovoLabs1952.

Structure of Insulin• 1951Aminoacidsequenceofinsulinby

BritishbiochemistFrederick Sanger (b1918)polypeptideof51aminoacidsintwochainslinkedbydisulphidebonds.1969BritishchemistDorothy Hodgkin (1910-1994)determinedspatialconformationbyxraydiffraction.

Developments in Insulin Therapy from 1952• SingleinjectionofPZIortwicedailysoluble

insulinandNPH.Toreduceinfectionrisksdisposablesyringe/needleintroduced1961byBectonDickinson,needlefreedeliverydevicesbyDerata1979andpopular‘penjet’,combinedsyringeandinsulinvialassingleunitdesignedbyGlasgowphysicianJohn Ireland (1932-1987)in1981marketedbyNovo1985.

• 1964InsulinpumpsbyDr Arnold KadishinLos

Angelesbutheavy,1972Dean Kamerdesignedlightweightformwornonbody.1978studiesbyJohn PickupandHarry KeenatGuy’swithcontinuoussubcutaneousinsulininfusioninshortpulsesfrombatteryoperatedpumpimprovedglycaemiccontrol.2003Medtronic/BectonDickinsoncombinedminipump/glucosemonitorworndiscreetly.Pumpsimprovedpersonalfreedombutwereexpensive.

Human Insulin• 1974byCibaGeigyexpensivewithallergic

sideeffects.1981geneticengineeringprojectbyGenentechandEliLillyusedgeneinsertionintoE.Coli.During1990’smanyUKpatientstransferredtobiosyntheticinsulin.MinoralterationsininsulinaminoacidstructuregaveinsulinanaloguessuchasLispro(Humalog)byEliLillyin1996withfastshortactingpropertiestocovermeals.Combinationwithregularinsulineg

HumulinR,NPH(NovolinN)andLente(HumulinL)nowavailable.

Experimental Treatment-Transplantation• 1916pancreaticgraftbyEnglishsurgeonFrederick Pybus (1883-1975),firstpancreatictransplantas

treatment1966byRichard Lillelei (1927-1981)professorofsurgery,MinnisotaUniversity.ImprovedisletcellisolationbyPaul Lacy (1924-2005)allowedtheirtransplantation.Relativelyfewtransplantsduetotechnicalproblemsandlimitedsuccess(10%)forinsulinindependence.Isletcelltransplantimproved2000byCanadianteamledbyJames Shapirousing‘Edmonton’protocolandmoreeffectiveimmunosuppression.

A Brief History of Oral Hypoglycaemic Agents (OHA) in Type 2 Diabetes• 1942oralsulphonamidefoundtolower

bloodglucosebutserioustoxiceffects.1955carbutamine,asulphonylurea,effectiveinoldernoninsulindependentdiabeticsstimulatingbetacellstoproducemoreinsulin.Othersaferfirstgenerationsulphonylureasincludetolbutamide(1956),andchlorpropamide(1958)andsecondgenerationglyclopyramide(1965),glybenclamide(1965)andgliclazide(1985).Metformin,biguanideintroduced1958increasedsensitivitytoinsulin,suppressingdigestionandglucoseabsorptionusedaloneorwithsecondgenerationsulphonylurea.MorerecentOHAincludealphaglucosidaseinhibitorsegBayeracarbosedecreaseglucoseabsorptionandthiazolidinethionesegpioglitazoneincreaseinsulinsensitivity.

Type 1 Diabetes is an Autoimmune Disorder• PioneerworkbySolomon Berson (1919-1972)

andRosalyn Yalow (1921-2011)developedaninsulinradioimmunoassaywhichshowedaninsulinbindingglobulininserumofinsulintreateddiabeticsandmeasureableinsulinconcentrationsintype2butlowconcentrationsintype1.1965BelgianpathologistWilly Gepts (1922-1991)reportedahighfrequencyofinsulitis,lymphocyteinfiltrationofisletcells,intype1patientsdyingwithinsixmonthsofdiagnosissuggestingan‘immunological’cause.Isletcellautoantibodiesdescribed1974byD Doniach (1912-2004)andGF BottazzoatMiddlesexHospitalassociatedwithspecificHLAtypesinjuvenileorinsulindependentdiabetes.Comparisonwithotherautoimmunedisordersandstudiesbynotably,Jon Nerupandcolleaguesin1975confirmedHLAlinktoB8&B15,andtheconceptthatgenestransmitatendencytodevelopdiabetes.However,the’trigger’forautoimmuneresponsehasnotbeenestablishedbutviralcauseshavebeenproposed..

Type 2 Diabetes and Genetic Vulnerability• Asearlyas600BCEobservedthatdiabetes

oftenraninfamiliesbutitwasnotuntilthe20thcenturygeneticstudiesbyG Pincus (1903-1967)in1933withfurtherworkin1947byH Harris (1919-1994)allwithinconclusiveresults.Theassociationbetweengeneticpredisposition,insulinresistance,centralobesityandhypertensionwasproposedin1988byGerald Reaven (b1928)andraisedthecurrentemphasisforlifestylemodificationindietandincreasedexercise.

FrederickSanger(b1918)

Dorothy Hodgkin(1910-1994)

Hans Christian Hagedorn (1888-1971)

Complications, Control & Testing

A History of Diabetes Mellitus: From Tasting to TestingProduced by the Institute of Biomedical Science History Committee

Complications of DiabetesNeonatal mortality• 1937increasehighlightedbyRaymond Titus

(1883-1949).AtKing’sCollegecaesareansectionbetween36thto38thweeksofpregnancyintroducedfrom1942.In1954improvedoutcomeswithbloodglucosenearnormalduringpregnancyreportedbyJorgen Pedersen (1914-1978).

New Technology & the Complications Control Trials• Impactofseriouscomplicationsfuelledaglobaldebateonneedforbloodglucosecontrolledtotwo

majortrials.USA1985-1993fortype1andUK1977-1997fortype2.Newtechnologieswereusedtoassessoutcomesofmoreintensivetreatmentandmaintainingbloodglucoseclosetonormalrangeandincludedglucosemeters,HbA1candurinemicroalbumin.

Glucose meters• FurtheradvancesinreagentstriptechnologyatAmesresultedinDextrostix(1964)usedtomeasure

wholebloodglucose.ToimproveprecisionandreliabilityAmesdevelopedtheAmesReflectanceMeterin1970.IntensecommercialdevelopmentshavetakenplaceduringthelastfourdecadesandawidevarietyofreagentstripmetersystemsareavailabletoGP’s,Clinicsandsignificantlythepatientsthemselves.Laboratorystafftodayplayanimportantrolein‘pointofcaretesting’andmanagementofglucosemeters.

Glycated haemoglobin (HbA1c) • HbA1cinbloodhaemolysatesofdiabeticsfirstdemonstratedbySamuel Rahbarin1968.In1976itwas

shownbyA CeramiandRonald Koenigthat%formedcouldberelatedtotheaveragebloodglucoseoverprevious4months,thelifecycleofredbloodcell.Thiswasasignificantfactorintheretrospectiveassessmentofbloodglucosecontroltotargetlimitsinthetrials.HbA1cisnowahighvolumeworkloadassayinalllaboratoriesusingmethodssuchasaffinitychromatography,HPLCorimmunoassay.

Microalbumin• Moresensitiveimmunoassayforurinealbuminwasdevisedin1963byHarry Keenandusedasanearly

indicatorofimpairedrenalfunction.Ithasbeenreplacedbyautomatedrenalfunctiontests.

ResultsDCCT (type 1 diabetes)• Foundsignificantlyreducedrisksofretinopathy,nephropathyandneuropathy.Ahigherriskof

hypoglycaemiawasreportedandnoreductionofriskofcardiovasculardisease.

UKPDS (type 2 diabetes)• Positivebenefitswerefoundforretinopathyandnephropathybyimprovedbloodglucoseandblood

pressurecontrol.Duetothemixoftreatmenteginsulin,sulphonylureas,metforminthiswasalongertrialandinterpretationofresultsmorecomplex.

2000: DIABETES BECOMES EPIDEMICWorldHealthOrganisationestimatedthat171millionintheWorldhavediabetesandprojectedto366millioninyear2030

2012: MOST NHS COSTS ON DIABETES ARE WASTEFUL (Diabetes UK)80%ofNHScostsindiabetesinvolvetreatmentofcomplications.2012: 24,000 WITH DIABETES ARE DYING NEEDLESSLY (Diabetes UK)Referstothenumberofpeoplefailingtohave9recommendedtestsfordiabetesatGPannualreview.

2013: DIABETES UK TOLL HITS 3 MILLION (Diabetes UK)Anincreasefrom2.2millionin2006andafurther850,000maybeundiagnosedtype2

DAILY NEWS‘Read All About It’:

Diabetes Makes the Headlines

Retinal scarring

Diabetic NodularNephropathy

Ame Reflectance Meter 1970

A Range of Modern Meters

Retinopathy• 1934MayoClinicstudies

showedrepeatedretinalhaemorrhagescauseofblindnessindiabetes.Around1950laserphotocoagulationfirstusedandmanylaservariationsfollowed.Morerecentlyspecialisedsurgeryintroduced.

Nephropathy• 1936Paul Kimmelsteil (1900-1970)and

Clifford Wilson (1906-1997)atHarvarddemonstratednoduleswithinrenalglomeruliwhichimpairedrenalfunction.Treatedfirstbyproteinrestriction,laterrenaldialysisandtransplantation

Neuropathy• ObservedbyJohn Rolloin1798andreported

byFrederick Pavyin1885affectingsensoryesp.hands,feetandtheautonomicnervoussystems.1954William Oakley (1906-1998)proposeddiabeticnervedamagesignificantfactorinperforatingfootulcersandgangrene.

Cardiovascular disease• Duringthe20thcenturyrepeatedreportsof

vascularlesions,earlymyocardialinfarctionandstrokesmorecommonintype2diabetesconfirmedby1950Framinghamheartstudy.Variouspathologicalmechanismsproposedforincreasedriskofatherosclerosis.Blockedarteriestothelowerlimbsarecommoncauseofgangreneaffectingtoes.