Could a breathalyzer detect cancer? - Julian Burschka

Prevodilac: Aleksandar Bošnjak Lektor: Ivana Korom

How is it that a breathalyzer can measure the alcohol content in someone’s blood,

Kako to da alkotest aparat može da izmeri količinu alkohola u nečijoj krvi,

hours after they had their last drink, based on their breath alone?

nekoliko sati nakon što su popili poslednje piće, samo na osnovu daha?

Exhaled breath contains trace amounts of hundreds, even thousands,

Izdahnut vazduh sadrži tragove stotina, čak i hiljada,

of volatile organic compounds:

štetnih organskih jedinjenja,

small molecules lightweight enough to travel easily as gases.

malih molekula dovoljno laganih da putuju lako kao gasovi.

One of these is ethanol, which we consume in alcoholic drinks.

Jedan od njih je etanol, koji konzumiramo u alkoholnim pićima.

It travels through the bloodstream to tiny air sacs in the lungs,

Putuje kroz krvotok do malih vazdušnih kesa u plućima,

passing into exhaled air at a concentration 2,000 times lower,

prelazeći u izdahnut vazduh pri koncentraciji 2,000 puta manjoj,

on average, than in the blood.

u proseku, nego u krvi.

When someone breathes into a breathalyzer,

Kada neko dune u alkotest,

the ethanol in their breath passes into a reaction chamber.

etanol u njihovom dahu prelazi u reakcijsku komoru.

There, it’s converted to another molecule, called acetic acid,

Tamo se pretvara u drugi molekul koji zovemo sirćetna kiselina,

in a special type of reactor that produces an electric current during the reaction.

u specijalnom tipu reaktora koji proizvodi eletričnu struju tokom reakcije.

The strength of the current indicates the amount of ethanol

Jačina struje pokazuje količinu etanola

in the sample of air, and by extension in the blood.

u uzorku vazduha, i po analogiji, u krvi.

In addition to the volatile organic compounds like ethanol

Pored isparljivih ogranskih jedinjenja kao što je etanol

we consume in food and drink,

koje koristimo u hrani i piću,

the biochemical processes of our cells produce many others.

biohemijski procesi naših ćelija proizovde mnoge druge.

And when something disrupts those processes, like a disease,

A kad nešto prekine te procese, kao bolest što može,

the collection of volatile organic compounds in the breath

kolekcija isparljivih ogranskih jedinjena u dahu

may change, too.

može da se promeni takođe.

So could we detect disease by analyzing a person’s breath,

Dakle da li bismo mogli da detektujemo bolest analizirajući dah osobe,

without using more invasive diagnostic tools

a da ne koristimo invazivnije instrumente za dijagnostiku

like biopsies, blood draws, and radiation?

kao što su biopsije, vađenje krvi i radijacija?

In theory, yes,

U teoriji, da,

but testing for disease is a lot more complicated than testing for alcohol.

ali testiranje na bolest je komplikovanije od testiranja na alkohol u krvi.

To identify diseases,

Da bi se identifikovala bolest,

researchers need to look at a set of tens of compounds in the breath.

istraživači treba da posmatraju skup od desetine jedinjenja u dahu.

A given disease may cause some of these compounds

Određena bolest može da uzrokuje da se neka jedinjenja

to increase or decrease in concentration, while others may not change—

povećaju ili smanje u koncentraciji, dok druga mogu da budu nepromenjena,

the profile is likely to be different for every disease,

šablon je verovatno drugačiji za svaku bolest,

and could even vary for different stages of the same disease.

a možda čak i varira za različite etape iste bolesti.

For example, cancers are among the most researched candidates

Na primer, tipovi raka su među najistraživanijim kandidatima

for diagnosis through breath analysis.

koji mogu da se dijagnostikuju putem analize daha.

One of the biochemical changes many tumors cause

Jedna od biohemijskih promena koju većina tumora uzrokuje

is a large increase in an energy-generating process

je veliko povećanje kod procesa generisanja energije

called glycolysis.

koje se zove glikoliza.

Known as the Warburg Effect,

Poznato kao Varburgov efekat,

this increase in glycolysis results in an increase of metabolites like lactate

ovaj porast u glikolizi prouzrokuje povećanje metabolita kao što je laktat

which in turn can affect a whole cascade of metabolic processes

koji zauzvrat može da utiče na celu kaskadu metaboličkih procesa

and ultimately result in altered breath composition,

i naposletku rezultira promenjenim sastavom daha,

possibly including an increased concentration of volatile compounds

verovatno uključuje povećanu koncentraciju isparljivih jedinjena

such as dimethyl sulfide.

kao što je dimetil-sulfid.

But the Warburg Effect is just one potential indicator of cancerous activity,

Ali Varburgov efekat je samo jedan potencijalni indikator prisutva raka,

and doesn’t reveal anything about the particular type of cancer.

i ne otkriva ništa o posebnom tipu raka.

Many more indicators are needed to make a diagnosis.

Mnogo više indikatora je potrebno da bi se ustanovila dijagnoza.

To find these subtle differences,

Kako bi našli ove subtilne razlike,

researchers compare the breath of healthy people

istraživači upoređuju dah zdrave osobe

with the breath of people who suffer from a particular disease

sa dahom osobe koja pati od neke određene bolesti

using profiles based on hundreds of breath samples.

koristeći šablone zasnovane na uzorcima stotine dahova.

This complex analysis requires a fundamentally different,

Ova kompleksna analiza zahteva fundamentalno drugačiji,

more versatile type of sensor from the alcohol breathalyzer.

prilagodljiviji tip senzora u odnosu na alkotest aparat.

There are a few being developed.

Nekoliko njih se razvija.

Some discriminate between individual compounds

Neki razlikuju individualna jedinjenja

by observing how the compounds move through a set of electric fields.

tako što posmatraju kako se jedinjenja pomeraju kroz niz električnih polja.

Others use an array of resistors made of different materials

Neki drugi koriste niz otpornika napravljenih od različitih materijala

that each change their resistance when exposed to a certain mix

gde svaki menja svoju rezistenciju kada je izložen određenoj mešavini

of volatile organic compounds.

isparljivih organskih jedinjenja.

There are other challenges too.

Postoje i drugi izazovi.

These substances are present at incredibly low concentrations—

Ove supstance su prisutne u veoma niskim koncentracijama,

typically just parts per billion,

obično samo nekoliko delova u milijardi,

much lower than ethanol concentrations in the breath.

mnogo manje nego koncentracije etanola u dahu.

Compounds’ levels may be affected by factors other than disease,

Na nivoe jedinjenja mogu da utiču faktori koji nisu sama bolest,

including age, gender, nutrition, and lifestyle.

uključujući godine, pol, ishranu i način života.

Finally, there’s the issue

Na kraju, postoji problem

of distinguishing which compounds in the sample

razlikovanja koja jedinjenja u uzorku

were produced in the patient’s body

su proizvedena u telu pacijenta

and which were inhaled from the environment

a koja su udahnuta u okruženju

shortly before the test.

neko vreme pred testiranje.

Because of these challenges, breath analysis isn’t quite ready yet.

Zbog ovih izazova, analiza daha nije skroz spremna za sada.

But preliminary clinical trials on lung, colon,

Ali preliminarne kliničke studije na raku pluća, debelom crevu,

and other cancers have had encouraging results.

i ostalim tipovima raka su imale ohrabrujuće rezultate.

One day, catching cancer early might be as easy as breathing in and out.

Jednog dana, rano otkrivanje raka može biti lako kao udisaj i izdisaj.