Tag: Health sciences

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Quality of Life at Seven Years Post-Stroke by Dr Michael J. Leach

Old stroke survivor

a life of low quality

yet high quantity.

A stroke, otherwise known as a cerebrovascular accident, is a serious health problem whereby blood flow to the brain is interrupted by a blocked or ruptured blood vessel. A stroke is life threatening and requires emergency medical attention. If an individual survives a stroke, then he or she may live with one or more long-term effects, such as memory loss, hemiplegia (i.e. paralysis on one side of the body), visual impairment, or speech problems. Such long-term effects can negatively impact on a stroke survivor’s quality of life across multiple domains: independent living, social relationships, illness, physical senses, and psychological wellbeing. While quality of life has been well studied in the short term after stroke, few studies have investigated quality of life among long-term stroke survivors.

In original research conducted as part of my Master of Biostatistics degree, I assessed quality of life at seven years post-stroke among people residing in the north-eastern suburbs of Melbourne. The validated Assessment of Quality of Life (AQoL) instrument was used to measure quality of life. In the AQoL instrument, scores range from -0.04 (worse than death) to 0.00 (death equivalent) to 1.00 (optimal). Among 1321 stroke cases with a mean age of 68 years, 413 (31% of stroke cases) were still alive at seven years post-stroke and 328 (79% of survivors) were assessed in my study. Of the 328 long-term stroke survivors assessed, 76 (23%) had very poor quality of life ranging from -0.038 to 0.100. Furthermore, 6% of patients had quality of life that healthy individuals deem worse than death (i.e. ranging from -0.038 to 0.00). The mean quality of life score at seven years post-stroke was 0.51. This score means that, if faced with the prospect of being an average seven-year stroke survivor, a given person in the general population would rather live in full health for half of his or her expected life span.

This research is important in that it highlights the dire need for interventions to improve quality of life in the long-term after stroke. Potentially modifiable factors associated with better quality of life in the long-term after stroke could be targeted to improve the quality of stroke survivors’ lives. In my original research, the potentially modifiable factors associated with better quality of life included lesser handicap and independence in activities of daily living (e.g. indoor mobility, dressing, and shopping). An example of a promising targeted intervention to improve post-stroke quality of life is cognitive training aimed at improving brain function. As cognitive training has been shown to make people more independent in activities of daily living over a five-year period, it is a promising intervention to improve quality of life in the long-term after stroke.

Original research:

Leach MJ, Gall SL, Dewey HM, Macdonell RAL, Thrift AG. Factors associated with quality of life in 7-year survivors of stroke. Journal of Neurology, Neurosurgery & Psychiatry. 2011; 82(12):1365-1371.  http://dx.doi.org/10.1136/jnnp.2010.234765

Dr Michael J. Leach is an Australian health researcher, biostatistician, and poet with a PhD in Pharmaco-epidemiology and a passion for health humanities. Examples of his science poems are available online: https://imagesofhealth.wordpress.com/.

If you enjoyed this sciku, check out Michael’s other sciku ‘Drug-Induced Hip Fractures‘, ‘The Psychopharmacological Revolution‘, ‘The Core Correlate of Covid-19 Vaccine Acceptance’, ‘The Early Impacts of COVID-19 on Australian General Practice‘, ‘The Burden of Bushfire Smoke‘, and ‘Australian Science Poetry‘ with science communicator Rachel Rayner.

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Transcription by Prof Sridhar Hannenhalli

To express or not

Here now a bit or a lot

That is the question.

 

Every cell in an organism contains an identical copy of the genome, except for rare somatic mutations, that encodes its entire gene complement. Yet, each of the hundreds of individual cell types in an organism utilizes a well-defined subset of the genes – imagine your neurons expressing genes that are normally expressed in skin cells. Thus the cell, starting from the single-celled embryo, must have a mechanism to control when, and how much of, each gene is expressed. This control is exercised, in large part, at the level of transcription – the process of reading the DNA encoding a gene on the genome and copying it into a messenger RNA (mRNA), which is eventually translated into the final protein product (or otherwise processed into a final RNA product).

Besides controlling normal development and defining the identity of individual cells, the response to a change in environment is also managed at the level of transcription.  This was first demonstrated by Jacques Monod and Francois Jacob in their seminal 1961 paper, showing that a group of E. coli genes that encode for proteins required to break down lactose is transcriptionally switched on or off depending on whether the growth medium is rich in lactose or glucose. They went on to win the 1965 Nobel Prize in Physiology or Medicine for their discovery.

Transcriptional control plays a critical role not only in development and environmental response, but also at a longer time scale in mediating evolutionary divergence across species. In their classic 1975 paper, Mary-Claire King and Alan C Wilson, observing very high levels of similarity between several proteins of chimpanzees and humans, concluded that the vast phenotypic differences between the two species could not be explained by such small degree of molecular divergence and are likely to be driven by the changes in the mechanisms controlling the gene transcription.

The role of transcriptional control in dictating natural diversity at multiple natural scales from cells within an organism, individuals within a species, and across species is now well established. This extends even to phenotypic changes associated with all complex diseases, and is underscored by the observation that the vast majority of genotypic signals associated with human diseases reside in non-protein-coding regions of the genome, thus focusing the research efforts in interpreting these signals in the context of transcriptional control.

Original research:

Jacob, F. & Monod, J. (1961) Genetic regulatory mechanisms in the synthesis of proteins. J Mol Biol 3, 318–356.  http://biotheory.phys.cwru.edu/phys320/JacobMonod1961.pdf

King, M. C. & Wilson, A. C. (1975) Evolution at two levels in humans and chimpanzees. Science (80) 188, 107–116. https://doi.org/10.1126/science.1090005

Hindorff, L. A. et al. (2009)Potential etiologic and functional implications of genome-wide association loci for human diseases and traits. PNAS 106, 9362–9367.  https://doi.org/10.1073/pnas.0903103106

Sridhar Hannenhalli is professor of Cell Biology and Molecular Genetics at the UMD, interested in transcriptional regulation and evolution. He is currently visiting IISc, Bangalore, as a Fulbright scholar. You can follow him on twitter @hannenhalli.

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Twisted naval string

Twisted naval string:

Forty turns of jelly and

contrary vessels.

 

Break benefits both before

severing the thread of life.

 

The umbilical cord has traditionally been cut (or at least clamped) 15-20 seconds after birth but increasingly research suggests that a longer delay before cutting is beneficial for both term and pre-term infants.

For term infants a delay of 30-60 seconds can increase haemoglobin levels at birth and iron stores in the first months of life. In preterm infants a delay can improve transitional circulation, result in the better establishment of red blood cell volume and decrease the need for blood transfusions.

A delay before clamping and cutting is therefore recommended by both the World Health Organisation and the American College of Obstetricians and Gynaecologists.

This sciku is actually an example of a tanka – the first two verses of a traditional renga, where haiku originate from. Learn more about haiku, renga and tanka here.

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Gamma sabres by Hannah Hall

Gamma sabres slay

Alzheimer’s amyloid plaques

with disco lighting.

 

Alzheimer’s disease is a neurodegenerative condition that worsens over time leading to problems with short-term memory, mood swings, behavioural issues and ultimately loss of bodily functions and death. But could flashing LED lights be a method of helping to treat the disease?

Exposing laboratory mice to LED strips flickering at 40Hz for an hour reduced beta amyloid plaque levels in the visual cortex by half, reduced Tau protein abnormalities and enhanced gamma oscillations (brain waves) – all of which are characteristics of Alzheimer’s disease. Iaccarino et al, 2016.

Hannah Hall is a Senior Consultant at Pragma Consulting Ltd in London. Though she studied Russian and French at university, she has broad interests and enjoys listening to the RadioLab podcast where she heard about this research.