Blog posts

The Asbestos Story: a tale of public health and politics

The Asbestos Story: a tale of public health and politics
Public awareness of the hazards of asbestos can be dated to the period immediately following the death of Nellie Kershaw aged 33 in 1924.  She had worked during the previous seven years in a textile factory spinning asbestos fibre into yarn. She died of severe fibrosis of the lungs. The pathologist, William Cooke, who found retained asbestos fibres in the lungs, called the cause of death asbestosis.  Nellie Kershaw was not the first case to be reported of lung fibrosis caused by asbestos. Montague Murray in 1899 had reported the case of a 33-year-old man who had worked for 14 years in an asbestos textile factory. He had died of fibrosis of the lungs which Montague Murray, also finding asbestos in the lungs, had attributed to inhaled asbestos fibres.  The patient had told Murray he was the only survivor from ten others who had worked in his workshop.

However, unlike the Montague Murray case, which had aroused little interest, the death of Nellie Kershaw and its cause was widely reported. It led to the government commissioning the Chief Inspector of Factories, Edward Merewether, with an engineer, Charles Price, to report on workers’ health in the asbestos industry. They found, among those still at work who had been employed for more than five years, one third had asbestosis and of those still working in the factory after 20 years, four-fifths had the disease.

The government introduced regulations in 1931 to control exposure to asbestos, together with arrangements for regular medical surveillance of the workforce and eligibility for compensation for factory workers with asbestosis. A benefit commented on by the workers in one factory was a clock on the wall becoming visible to them for the first time. (more…)

Leprosy in 2018: an ancient disease that remains a public health problem today

World Leprosy Day. Image courtest of Wellcome Collection.

28 January 2018 is World Leprosy Day

I have always found leprosy a fascinating disease. It is an incredible example of how microbiology, immunology, and social sciences can collide and impact significantly on human health.

Leprosy has been affecting humans for at least 4000 years. It has played a huge part in teaching us about disease caused by bacteria. In 1873 when Hansen discovered Mycobacterium leprae in tissue samples from patients with leprosy, this became the first bacteria to be directly linked to causing disease in humans. Since then we have developed an understanding of the complex range of types of leprosy that occur depending on how an individual’s immune system responds to the challenge of infection with Mycobacterium leprae. We have also observed the consequences of the deformities and disability caused by the body responding to Mycobacterium leprae, which favours human nerves and skin. In turn, we have seen how the appearance of individuals with disability and disfigurement from leprosy has driven stigma, misinformation, and the discrimination of those affected by the disease.

For many people in the UK and around the world, leprosy, or Hansen’s disease, is an ancient condition of our ancestors. It is something that we hear about in religious scripture or watching films like Ben-Hur or the Life of Brian.  Associated with exile from communities, deformity, and poverty. Something that no longer affects the modern world that we now live in.

Leprosy is often referred to in Sanskrit from around 1400 BC, with the term “kushtha” used to describe it. This translates to “eating away”. Courtesy of Wellcome Collection.

In 2000, the World Health Organisation (WHO) made an announcement that leprosy had been eliminated as a public health issue, with the global prevalence finally falling below one case per 10,000 people. This was the culmination of many years of identifying and treating patients with leprosy. This included the development of multi-drug therapy – a real game-changer in the treatment of Hansen’s disease. In total, over 16 million people affected by leprosy were treated, often free of charge. This was a great success.

And so for the elephant in the room. If we have eliminated leprosy as a public health problem, why do we still need to worry about World Leprosy Day?

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Could gut hormones help make Dry January last all year?

After the excesses of Christmas and New Year, it has become fashionable for January to be promoted as a time for reassessment and resolutions. There are promises and attempts at living a healthier lifestyle, including stopping drinking alcohol (‘Dry January’), joining that gym, stopping smoking, and eating better. However, we know how difficult it is to maintain behaviour change over the longer term. People start drinking excessively again, put back on the weight they lose, start smoking again, and their attendance at the gym wanes. For people who have hazardous levels of drinking, and those who are dependent on alcohol, this is particularly problematic.

If people manage to stop drinking alcohol, we know that there are high relapse rates. In some studies, 60% of people with alcohol dependence have started drinking alcohol again after 6 months of abstinence. This is often precipitated by exposure to social events and situations where there is drinking, and stresses with family, job, and social circumstances. What is needed are strategies to help prevent relapse into drinking. While psychological and group support can be of benefit, there is also a potential role for medications to help reduce the craving for alcohol and the response to stress.

The Division of Brain Sciences in the Department of Medicine at Imperial College London are currently running a research study in this area. We are investigating the potential benefit of a completely novel therapeutic strategy to prevent relapse in alcohol dependence. This is the ‘Gut Hormone in Addiction’ (GHADD) Study, funded by the Medical Research Council. This is targeting hormones from our guts, which can act on our brain to influence eating and addictive behaviours. (more…)

How machine learning will transform the way we look at medical images

Medical imaging is key in today’s delivery of modern healthcare, with an immense 41 million imaging tests taking place in England in every year. Thousands upon thousands of patients safely undergo imaging procedures such as X-ray, ultrasound, and MRI every day, and the product of these tests – the images – play an essential role in informing the decisions of medical professionals and patients in nearly every area of disease.

At its core, medical imaging is the application of physics, and sometimes biochemistry, to visually represent the biology and anatomy of living humans. We have progressed from the first, blurry, x-ray in 1895, to being able to measure minute changes in oxygenation within the brain; whilst major technological advancements continue to be made every year.  In the field of medical imaging, these techniques are applied to expand our understanding of the human body and disease in research settings, but much of this technology does not actually make it into every day clinical practice. For me, this has been the drive to move from a career in sonography into clinical research: to implement novel technology and investigate how it can be used to improve patient care.

One of these advancements is the use of image analysis technology to obtain more information from medical images. There has always been an interest in the use of computers to analyse medical images as computers are not biased by optical illusions or experience like human readers are. In image analysis, an image is no longer considered as visual, but rather as digital information. Each pixel contains a value representing biophysical properties, and you can write a program that finds a specific pattern or feature across the image that can represent disease. However, this process is time-consuming, and a single feature probably doesn’t represent a disease very accurately. (more…)

Death of a cell: the vital process of tidying up cell debris to prevent blood clots

Your cells die every day. Don’t worry, your body is protecting itself. In a process known as apoptosis or programmed cell death, cells that are no longer needed commit suicide. Some cells are only required for a short time, they may be infected by a virus or develop harmful cancerous mutations. Cell death is also an essential part of development from an embryo. For example, mouse paws begin as spade-like structures and only form the individual digits as the cells in between die. During apoptosis the cells fragment into smaller apoptotic bodies, and their cell surface is flipped open to display lipid molecules called phosphatidylserines, which act as an ‘eat me’ signal to recruit cells called macrophages to engulf them, before their contents spill out and damage the surrounding tissue. This is a process known as efferocytosis.

However cell death is not always so orderly. Some cells suffer premature death known as necrosis, where they burst open for various reasons such as infection, physical trauma or extreme temperatures. As the cell’s contents are released into the open, an inflammatory response is triggered. Studies are ongoing to establish the many mechanisms by which this process occurs. For example, it is known that proteins on the surface of immune cells, called pattern recognition receptors or PRRs, detect the material released by dying cells, and trigger the expression of genes leading to the release of inflammatory substances. When an infection occurs, the immune response is usually short-lived as it rapidly kills the infection. However, when cell necrosis and subsequent inflammation occurs over a longer period, the substances released by macrophages – that have migrated in to engulf the dying cells – can damage the surrounding tissue, resulting in a build-up of dead cells.

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Big hearts and giant genes: What lies at the end of the yellow brick road?

Upasana Tayal was shortlisted for the MRC Max Perutz Science Writing Competition 2017 for the following article:

“Hearts will never be practical until they can be made unbreakable”, said the Wizard of Oz. “But I still want one”, replied the Tin Woodsman.

Your heart makes you human, makes you love, and keeps you alive. In just one year, it will beat 40 million times, without rest or time off for good behaviour. A pretty impressive piece of machinery you might agree, no wonder the Tin Man wanted one so much.

And like many things in life, he may have wished for a big heart at the end of the yellow brick road.

He would be forgiven for imagining a big heart to be a good thing, extra caring and compassionate, and if the Tin Man was scientifically inclined, more effective at doing its job of pumping blood around the body.

Unfortunately for the 1 in 250 people in the world living life with a big heart, the reality is very different. (more…)

Would you give the gift of a kidney to a stranger in need?

 

As far as generous Christmas presents go, donating your kidney seems for many at the extreme end. However, for a few lucky kidney disease patients, this is the gift of a lifetime. Known as unspecified or non-directed altruistic kidney donation, this form of live organ donation is on the rise, and could potentially wipe the waiting list if more stepped forward. I met Frank Dor, a consultant transplant surgeon and Head of Transplantation at Imperial College Healthcare NHS Trust, who has carried out hundreds live organ donations.

The waiting game

Frank receives a phone call notifying him that a kidney from a deceased donor has been allocated to one of the recipients at Imperial. This single kidney is in high-demand as there are around 5,000 people on the UK NHS Blood and Transplant (NHSBT) waiting list for a kidney; some waiting for up to five years. Unfortunately, a few hundred of these will die in the meantime for lack of one.

These patients have chronic kidney disease, meaning they have lost their kidney function so dialysis three times per week becomes the norm. However, life on dialysis is debilitating, difficult and time-consuming. “Dialysis is merely a way of keeping people alive, it’s just a temporary measure that can never fully replace the kidney function,” Frank tells me. “Eventually patients on the waiting list get to a point where they start to lose hope and stop making plans for the future”.

The long-term solution is receiving a kidney transplantation, of which there are two types – living and deceased. Transplantation provides patients with the opportunity for a longer and better quality of life, with patients typically gaining 10-20 years of life compared to dialysis. However, the odds for receiving one are not favourable: there are 1,500 patients on dialysis in Imperial College Healthcare NHS Trust but only around 200 of those get transplanted every year. There is a huge gap between supply and demand nationally and internationally. (more…)

Festive feasting: the good, the bad and the microbiome

As the festive season approaches, one wonders how our bodies prepare for the enormity of food that will be ingested in a relatively short space of time.  In the UK alone, the average person consumes 7000 calories on Christmas Day alone.  This is three times the recommended calorie intake per day, and most of us will have reached the recommended calorie intake before Christmas lunch has even been served. And of course, it’s not just about eating more. We are also a great deal more sedentary, with the average person in the UK spending 5.5 hours a day in front of the television over the Christmas period desperately awaiting reruns of Blackadder and yet another Christmas special!

Of course, this massive increase in consumption over the festive period inevitably means we put on weight, with research showing maximum weight gain reached within 10 days of Christmas Day, peaking around 3 January, and then falling.  However, despite this relatively rapid increase in weight in the space of a few days, approximately half of the weight gained seems to remain until the summer months or beyond.  The cumulative effects of this annual increase in weight during the holiday period likely contribute to one’s overall lifetime weight gain.

Obesity results from a mismatch between food intake and energy expenditure.  So is this festive weight gain a result of eating too much and spending too much time on the sofa?  What if it was more than just that? We now know that the gut is a crucial organ in the maintenance of energy homeostasis.  It releases a whole host of hormones such as glucagon-like peptide-1 and peptide YY that regulate appetite in response to nutrient intake.  Much of my work has focused on looking at the effect of dietary protein on appetite.  High protein diets reduce food intake and improve body composition, and if people can stick to them, they lose weight.  (more…)

How COPD patients can sing their way to better health this Christmas

Carol Singers (CC BY 2.0)

Singing carols is a big part of Christmas cheer, but not many people realise that singing can also be helpful for people with lung disease. COPD is an extremely common condition – there are 1.3 million people with this diagnosis in the UK. Existing treatments help to some extent, but do not reverse the underlying pathology, meaning that even with optimal care many patients remain breathless with activity limitation and poor quality of life. This symptom burden represents a major area of unmet need. Singing for Lung Health (SLH) groups are a potential way for patients to gain skills to improve control of their breathing and posture, reducing symptom burden and enhancing wellbeing.

What is singing for lung health?

Singing for lung health involves taking part in classes led by a specially trained singing teacher. Patients learn techniques to help control their breathing and posture as part of a group activity which is fun and sociable. The goal for the groups is to get better at singing, an artistic objective. By doing this individuals gain skills that help them to cope with their lung condition, a health improvement objective. The classes have a particular focus on activities and exercises that are helpful for people with lung disease and so differ from more generic “singing for well-being” groups.

Singing for lung health has grown from a few small clinical trials to more than 80 groups nationally. As well as the plausibility of an approach based on learning to control the breath in people with lung disease, singing is also a fun social activity. Results from the Royal College of Physicians COPD audit show that provision of pulmonary rehabilitation is still limited, so there is a need for activities to sustain the physical and social benefits that these produce once people have completed them. For some people, taking part in a singing group may be a useful stepping stone to agreeing to join a formal rehabilitation program. (more…)

World AIDS Day: Professor Robin Shattock on the elusive HIV vaccine

World AIDS Day takes place annually on 1 December as an opportunity for people worldwide to unite in the fight against HIV and to show support for people living with HIV/AIDS.

To mark World AIDS Day 2017, we have published a series of blog posts to highlight the important and varied research that takes places at Imperial. Three experts from Faculty of Medicine share their interest in HIV/AIDS which spans from the elusive vaccine to the economics of the epidemic.


Where are we in the battle against HIV/AIDS?

The past thirty years have seen enormous gains. We’ve seen the development of highly effective therapy that today can ensure the health of an HIV positive individual for rest of their natural lifespan. We used to speak of HIV/AIDS as if they were the same thing, now you can be HIV positive and never develop AIDS (Acquired Immunodeficiency Syndrome). Globally over 18 million people are now receiving life-saving drugs, preventing millions of deaths each year. Treatment also dramatically reduces the risk of passing on the infection. Excitingly, recent studies have shown that taking a daily pill (known as pre-exposure prophylaxis or PrEP) can prevent people from contracting HIV infection and this is now being made available in the UK.

However, significant challenges lie ahead

Treatment is for life and is not a cure; we are currently unable to eradicate the virus once someone has been infected. As many as a third of individuals infected with HIV are unaware that they have contracted the virus and late diagnosis significantly impacts on the benefit of available treatments. While great strides have been made to make global treatment accessible, only half of those currently infected are accessing treatment and for every individual starting treatment, one or two people are newly infected. This means that the population requiring life-long medication will continue to expand with associated pressure on global financial resources and already stretched health systems. (more…)