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It’s ok for scientist to take a year off on maternity leave

I was talking to another (more junior, female) post-doc the other day about juggling childcare and working part-time. I said it’s working well in general but next time (I’m currently pregnant with baby two) I will be taking off the maximum amount of time which is 12 months plus accrued leave. Her response was astonishment that I will be away from work for so long…How will I keep up with research? I’ll fall behind on publications, my boss might not like it…To me this list of reasons for not taking more than a few months off is reminiscent of the ridcululous advice I was given when my daughter was born: If you don’t put her down you’ll be carrying her to school when she’s 10, if you nurse her to sleep she’ll never learn to sleep by herself, you’ll turn her into a spoilt brat if you respond to her cries straight away….

After my first pregnancy I took 11 months off . I made the most of my time away from work, as I’ll do this time around. When I went back to work I changed to part-time hours, as did my partner. I read papers during my leave. I also had meetings with my PhD student and PI every six weeks or so. I took my daughter along to most of these meetings unless her dad was able to look after her while taking a long lunch break (he’s not a scientist but used to work in a building nearby).

During my first maternity leave only three papers that had a direct impact on my research were published. There were a few others that were of interest. I read more papers in the year I had off than I have ever read in a year while working. As with falling behind on publications, if you are productive before taking any leave, you will be afterwards too. A year off is not going to change that. In fact, I seem to be more productive while on leave than when I’m doing experiments because I have time to get away from the laboratory and reflect on the results I have so far and how I am going to take my project and career forward. (Maybe everyone should spend a week or two working from home once in a while to reflect on their work and how to take it forward.) A few months into my last maternity leave I was an author on a paper published in the Journal of Immunology (see here) and this time, two weeks into my leave another paper was submitted and a third is being written. I am also writing a project grant to extend my current contract and having meetings with another PI every 6 to 8 weeks to set up a collaboration. I have already told him that I will be bringing my son along to these meetings and if I need to I will nurse him during the meeting. Having children himself, he was happy with that.

When do I have the time to do this? I enjoy work enough to read papers while the children sleep and also while they are having some time alone with their dad. Life isn’t all about work though. There are other things I enjoy doing too such as gardening and getting back into running (see other blog here – a work in progress!).

My boss not liking that I’m taking so much time off? He doesn’t have a problem with it. Besides, even if he did, taking 52 weeks off is my right.

Work will always be there but it’s important to spend time with the family and children grow up so fast. 

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Blood and Eyes – The messier the better!

The Blood and Eyes workshop for families that was funded by the Biochemical Society

Biochemical Society

A Biochemical Society funded outreach activity at Bridgwater Science Festival.

Guest post by Tarnjit Khera (University of Bristol, UK)

OLYMPUS DIGITAL CAMERABlood is messy and children like mess so what better way to teach children about the components of blood than letting them make it themselves? During the activity we discussed the role of each ingredient as it was added to a cup. Dried cranberries played the role of oxygen-carrying red blood cells, marshmallows were the bigger infection-fighting white blood cells and sugar glitter was used to depict platelets, which help scabs form. For the serum diluted milk containing food colouring was used. Each component was added in the ratio found in real human blood. Nearly all of the children knew blood is red, it keeps us alive and circulates around our bodies. The amount of information I gave in snippets was determined by the age of the child and the knowledge they…

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Just can’t plan for illness

So, I thought I had been organised enough to sort out all of the experiments I need to carry out for a grant application. The experiments will be done by Easter and then after a break I will write the application. Already I was regretting planning experiments that require me to go into work over the weekend, every weekend for three weeks – what is the point of working part-time if I then also spend about four hours every weekend working? The whole point of working part-time was to spend time with my daughter and not miss her growing up. (I’m digressing.)
Just when I was feeling smug over my plans and self-congratulating myself for being so organised, I come across news that throws a spanner in the works. I decided to check my emails on my day off: Chicken pox has infected a child in the same nursery room as mine!
My daughter has had a fever for about a week now. Does she have a bug or is she teething? Who knows. I checked her over for spots, especially her scalp and behind her ears – nothing. But the incubation period for chicken pox is up to two weeks so she might still develop a rash, or not, as the case may be. We’ll just have to wait and see. If she does get chicken pox her dad and I will just have to juggle looking after a poorly toddler and carrying out essential work duties between us.
I was going to order her chicken pox vaccine (see my blog here and here) later this week but now it might not be needed…

 

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The Marvellous Multi-faceted Macrophages

Macrophages in a tissue culture dish

Macrophages in a tissue culture dish

What can macrophages do?

Most people know about the cleaning capabilities of macrophages but there is much more to macrophages than this.  Albeit, macrophages do ‘eat’ dead or damaged cells but what is not commonly known is that they do not just dissolve their ‘meal’, they  process their meal and then present it to T cells (another type of white blood cell) to show them the enemy for future reference. Macrophages also release signals calling for back up from other white blood cells. This, in general terms, is known as the inflammatory response. Macrophages also release toxic chemicals during inflammation, thereby destroying nearby tissues as well as the infecting pathogens (disease-causing organisms). These chemicals are oxidants: reactive oxygen species and nitric oxide. The very same oxidants health magazines warn people about and tell us we need to eat more anti-oxidants to counter.

They are also involved in the wounding-healing process and in the formation of blood vessels, both during ordinary foetal development and, then later in life, during disease (for example, in cancer). During the wound healing process, macrophages are the key regulators of repair, and involved in scar tissue (fibrosis) formation. They are in close contact with blood vessels during both development and during diseases such as wet age-related macular degeneration. Upon activation by cancer cells, macrophages release a variety of different types of proteins, many of which are important in cancer metastasis (spreading of cancer). The presence of a certain type of macrophage – tumour associated macrophage (i.e. TAM) correlates with poor prognosis in a variety of cancer types.

Macrophages play a pivotal role in diseases associated with low level chronic inflammation such as during cardiovascular disease, diabetes and cancer. These conditions have one thing in common – obesity. Obesity-induced chronic inflammation increases their risk. Recently, macrophages have been found in the fat around internal organs (known as visceral fat). The types of macrophages within the viscersal fat of a lean person and an obese person are different (the two types of macrophages are M1 and M2, more on this below). Fatty tissue sends signals (chemokines) to recruit and retain macrophages and these macrophages have a role in chronic inflammation and insulin resistance leading to type II diabetes.

Macrophages play a key role during cardiovascular disease. They are present in clogged arteries (atherosclerosis) within the plaques, affecting their stability where they ‘eat’ (phagocytosis) the lipoproteins. Once engorged, they turn into cholesterol-laden foam cells.  These macrophages seem unable to leave the plaque. They make inflammatory proteins, degrade their surrounding structures (by producing matrix-degrading proteases) which thin the cap on the plaque and eventually die. These dead cells make up the necrotic core of the plaque and contribute to its rupture. Unstable plaques are causal of myocardial infarction and stroke.

How do macrophages do this?

Courtesy of Dr. Volker Brinkmann, Max Planck Institute for Infection Biology, Berlin/ Germany

Macrophages act differently depending on their environment. When they are involved in inflammation, they are pro-inflammatory (also known as M1) but when they are involved in wound healing they are regulatory (also known as alternatively activated or M2). The macrophage behaviour depends on which signalling molecules are present in the tissue or organ. Some signalling molecules make macrophages into M1 while others make them into M2. One example of a signalling molecule (cytokine) that can make macrophages inflammatory is called tumour necrosis factor (TNF). Without TNF to activate them, macrophages cannot get rid of infections such as TB. When things go wrong and the immune system starts attacking the body (autoimmune disease) as in rheumatoid arthritis, Crohn’s and non-infectious uveitis (a disease affecting the eye and eventually leading to blindness), TNF is the culprit.

Other signalling molecules, such as IL-4 and TGFβ1, make them into M2 macrophages. M2 macrophages form scar tissue and produce a protein called VEGF that sends a signal to blood vessels encouraging them to make branches and more blood vessels. These macrophages turn off the inflammatory response.

These macrophage subsets are not distinct, there is overlap and macrophages can change their function depending on their environment.

Where do macrophages come from?

Monocytes and macrophages are very similar. Monocytes are formed in the bone marrow and then enter the blood stream. They circulate around the body in the blood until they are needed within a particular organ or tissue. These tissues make and secrete signalling molecules (known as cytokines or chemokines) which attract cells in from the blood. Once these monocytes leave the blood and enter tissues or organs, they turn into macrophages. These macrophages have different names depending upon which organ they are in. For example, in the kidneys they are called mesangial cells and in the eyes and brain they are called microglia.

The ratios of different types of macrophages vary in healthy and ill people and mice. Illness includes people with an infection, autoimmune disease, cardiovascular disease and obese people.

Here is a (short) list of future offerings:

  • Macrophages and fat tissue
  • Atherosclerosis
  • The importance of TNF
  • Age-related macular degeneration

Sources:

ResearchBlogging.org
Tarnjit Khera (2014). The Marvellous Multi-faceted Macrophages Scitkk.Wordpress.com
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Creative Commons Licence
Scitkk by Tarnjit Khera is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Based on a work at Scitkk.wordpress.com.
Permissions beyond the scope of this license may be available at Scitkk.wordpress.com.