Boj proti rakovine sa ukázala byť jedným z najväčších intelektuálnych a praktických výziev modernej doby. Pred sto rokmi, chirurgické zákroky podporované skorých foriem rádioterapie boli jedinými zbraňami k dispozícii lekárov. Odvtedy, rad kľúčových otáčok sa zmenili, že.
Prvé bolo zavedenie chemoterapia, vo forme liekov, ktoré boli odvodené, ironicky, z horčičného plynu, ktorý bol použitý ako zbraň v priebehu prvej svetovej vojny. Lekári, ktorí vykonali pitvy obetí plynových poznamenať, že inhibujú bunkové delenie, a vyvinuté verzie, ktoré pomohli zastaviť nádorové bunky množenie. Tie sa stali bežné ošetrenie v roku 1950.
Ako genomické výskum pokročil v 20. storočí, Vedci použili tieto znalosti k vývoju nových spôsobov liečby. Nedávne pokroky zahrnuté cielenej liečby. Tie sú konkrétnejšie v ich boji proti nádorom, pretože pôsobí na molekulárnych cieľov spojených s určitými rakovinovými bunkami, zatiaľ čo väčšina štandardné chemoterapie pôsobí na všetkých rýchlo sa deliacich buniek, či už ide o normálne alebo rakovinové.
Napríklad, asi jeden z piatich pacientov s rakovinou prsníka, nádorové bunky majú príliš veľký rast podporujúci proteín známy ako HER2 na ich povrchu. Rakoviny prsníka sa moc tohto proteínu sú veľmi agresívne, vedci zistili,. rad liekov, ako je napríklad Herceptin, boli vyvinuté s cieľom zamerať sa tento proteín a blokuje šírenie rakovinových buniek. Tieto cielenej liečby sú dnes oporou v boji proti rakovine.
Aké sú hlavné problémy?
Great dochádza k pokroku, but the emerging problem may be financial rather than technical. The new generation of drugs being developed are very expensive, raising questions of affordability.
Take the fledgling technology of immunotherapy. Cancer cells possess a sort of secret handshake that persuades T-cells, a key part of the body’s anti-disease defences, not to attack them. In the 1990s, scientists discovered a molecule on T-cells that was part of this handshake. It is known as programmed death 1 (PD1) a, since its discovery, researchers have been trying to disrupt its function.
The new drugs unveiled in Chicago last week are the result of this work. Trials on patients with advanced melanoma, which has a high death rate, have already produced encouraging results, but scientists warn that there could be serious side-effects in some patients.
Dementia is not actually a disease. It is the outcome of many different conditions. Alzheimer’s disease is the most common of these but others include vascular dementia and frontotemporal dementia. All of these forms share common symptoms, však. These include memory loss, confusion and personality change.
While dementia is certainly not an inevitable outcome of getting old, the likelihood of developing the condition undoubtedly increases with age. teda, as infectious diseases were vanquished in the UK, and mortality rates for cancer and heart conditions forced down, more and more people have been able to live to old age. (Life expectancy in the UK is now 79 for men and 83 for women.)
dnes, it is calculated that there are now more than 850,000 people with dementia in the UK.
podľa 2025, the number of cases of dementia in the UK is expected to rise to more than 1 milión. podľa 2050, it is projected to exceed 2 milión. okrem toho, the condition has been found to be particularly common in women. z 850,000 dementia patients in Britain, 500,000 are female. Ako výsledok, women over 60 are now twice as likely to get dementia as breast cancer.
Scientists are now working on ways to use genetic and stem-cell technologies to understand the detailed causes of the various forms of dementia and, in the long run, to develop drugs that could slow down the loss of faculties in those affected by the condition.
Scientists caution that this aspiration remains a long-term goal and warn there is much work that still needs to be done.
What are the problems?
A key problem for those trying to tackle dementia is a lack of resources. Tam boli veľké investície do srdcových chorôb a výskum rakoviny v posledných rokoch a tie pomohli znížiť úmrtnosť.
Ale to sa nestalo s demenciou, povedal Matthew Norton, vedúci politiky Alzheimerova Research UK. "Stačí sa pozrieť na čísla,"Povedal.
"Celkové výdavky vo Veľkej Británii – z charity a vlády – Na demencie u 2013 Bol 73,8 m £. naproti tomu, na rakovinu, Táto suma bola 503 m £. "To znamená, že underfunding redukovanú pracovnú silu, hovoria aktivisti. Tam sú niektoré 3,600 demencie výskumníci pracujúci v -Asi UK 19,000 menej ako tých, ktorí pracujú v boji proti rakovine, hoci demencie stojí ekonomiku Spojeného kráľovstva viac. tak, Šanca na získanie liečby spomaliť alebo zastaviť stratu schopností spojených s demenciou bude obmedzený, hovoriť výskumníkmi.
Over the past 50 leta, there has been an impressive improvement in mortality rates from cardiovascular disease in Britain. This point was precisely summed up by Peter Weissberg, medical director of the British Heart Foundation. “The foundation was established in 1961, when heart disease was ravaging the country. It caused nearly half of all deaths in the UK in that year.”
With hindsight, it is not hard to see why. Smoking levels were four times higher than today, while eating foods high in saturated fats – whole milk, butter and red meat – was the norm.
dnes, those foods have been replaced by lower-fat options, vegetable oils, skimmed milk and poultry. We have medicines to reduce blood pressure and cholesterol levels, and it is possible to open blocked or narrowed arteries without major surgery.
Devising drugs to treat damaged hearts suffers from a key problem: they are difficult to test. “We cannot keep cutting patients open to remove heart-tissue samples. That is just not practical or ethical,” said Chris Denning of Nottingham University.
A solution for scientists in recent years has been to turn to the use of stem cells. At Nottingham University researchers have taken cells from patients’ skin and bathed them in nutrients in order to transform them into stem cells, a type of cell that can be turned into any tissue. These cells are then developed into heart cells, which are kept in Petri dishes for testing purposes.
“That means they are ideal for trying new drugs on. It is an incredibly important development,” added Denning.
Other scientists believe that it may be possible to use stem cells to directly repair, damaged hearts in the near future.
What are the problems?
Although medical procedures continue to improve prospects for saving the lives of those who suffer from cardiovascular disease, there are a host of epidemiological issues that threaten to offset these benefits.
Napríklad, the rate of smoking declined sharply between 1972 a 1994 but the fall-off has since slowed down. And the prevalence of heavy drinking has not changed substantially since the 1970s. Worse, childhood obesity has been increasing in both boys and girls since the mid-1980s, while adult obesity rates are also continuing to rise – as is the incidence of diabetes in the UK. All these factors increase the risk that heart disease mortality rates could rise again in the near future.
Weissberg has warned that these factors “threaten to derail the decreasing trends in heart disease and death rates that we are now experiencing”.
Defeating the scourge of infectious disease in the western world is generally attributed to the development of vaccine programmes and antibiotics, although improved sanitation and health education have also been key factors.
“In fact, death rates from tuberculosis, a pernicious killer, had begun to drop by the mid-19th century,” said Carsten Timmermann of Manchester University. “In 1838, there were around 4,000 deaths per million as a result of TB, but this had dropped to around 1,000 by 1900. Vaccines and antibiotics had nothing to do with that. V skutočnosti, it is not clear why the decline occurred at all. But it is also evident that programmes such as the BCG vaccine project had really stopped tuberculosis being a serious killer by the middle of the 20th century.”
In the west, most infectious diseases are now kept at bay. Avšak, the balance is an uneasy one. “In the 1960s, a US surgeon-general was alleged to have claimed that infectious diseases had been completely defeated,” said Jeremy Farrar, who is head of the UK Wellcome Trust.
“The story may be apocryphal but it certainly sums up attitudes at the time. potom, a couple of decades later, we had the arrival of HIV in the west and a very clear lesson about the ever-present danger of infectious diseases, ktorý can spread very quickly from other parts of the world.”
okrem toho, the rise of antibiotic resistance – a result, in part, of overuse – has led to growing fears that one of the west’s key defences against infectious disease may be lost in the near future, unless pharmaceutical companies speed up the development of new versions.
What are the problems?
In an increasingly connected world, it’s more and more difficult to contain infectious diseases. Changes in weather patterns and increased migrations from areas affected by rising sea levels or spreading deserts will also intensify the risk of new diseases or new strains of existing conditions arriving in the west.
“In developing nations, we have replaced the problems of infectious disease with health issues such as diabetes and obesity,” said Farrar. “But in developing nations, they still have major problems with infectious diseases – malaria, TB and HIV, napríklad – but are also being affected by obesity and diabetes. Countries such as these – Vietnam is a good example – need considerable help from global agencies such as the World Health Organisation. Avšak, these agencies are not getting the support they need from the west any more.”
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