Category Archives: Blogs

FIFA 11+: An effective way to reduce injuries in amateur soccer players? — Rugby Science

by Aminah Emeran Soccer is arguably the most popular sport globally, with an estimated 200 million players worldwide (1). There are many health benefits of playing soccer, including reducing the risk of type 2 diabetes and hypertension (2). Despite its health benefits, soccer also poses a significant risk of injury (3), particularly to areas such […]

FIFA 11+: An effective way to reduce injuries in amateur soccer players? — Rugby Science

Wimbledon – it’s not all just strawberries and cream — Rugby Science

by Jenna Bloom When you’re watching Wimbledon, have you ever wondered how busy the doctors and physiotherapists are behind the scenes? Well, McCirde et. al. (2016) wanted to determine the rate of injuries that occurred during Wimbledon, which could assist scientists to eventually develop measures to prevent injuries. (3) They study found that there were […]

Wimbledon – it’s not all just strawberries and cream — Rugby Science

Overuse injuries in basketball: A dribble of sprains and pains — Rugby Science

by Tumelo Lethule  Basketball has become one of the most popular sports in the world and has given us the pleasure of gushing over NBA stars such as O’neal, James, Curry and of course, the legendary Jordan. As a non-contact sport, basketball remained one of the safest sports ever played. However, as the sport seems […]

Overuse injuries in basketball: A dribble of sprains and pains — Rugby Science

Does dissection of the human cadaver cause anxiety?

by Courteney Collins

As an anatomy student, I am often asked “how do you handle dissections, isn’t it scary?”. Students are taught that dissections provide a good foundation for a doctor-patient relationship (Bastos and Proenca, 2000). However, people begin to view doctors as insensitive, lacking human emotion. Recently there has been much research done on the emotional state medical students face when experiencing dissections.

Figure 1: Dissection Hall, Institute of Anatomy, University of Greifswald 2002.  

Fox (1979) described that students are naturally distraught when dissecting a human cadaver and in order to cope with it they develop a “scientific attitude”. The most common reactions to the experience are physical and psychological and have shown to reduce after the first few weeks of dissections (Penney,1985). Despite all the different views, this study proved that anxiety was the most common emotional reaction.

The aim of this research was to study students’ anxiety response to dissection and determine the factors involved in this response.

Three studies were carried out in the dissection room at the department of Human Anatomy and Embryology II at the Complutense University, Madrid, during the 3 academic years 2000–2003.The participants of the study were first time matriculants in the anatomy department. In the three studies, the student’s anxiety level was measured at different times and the student’s anxiety trait.

The first study showed that students anxiety levels decreased the more they experienced dissections. It makes sense that most students experience anxiety because they don’t know what to expect.

The second study demonstrated that the once students became comfortable with dissections, their anxiety reaction was a result of personal traits. This means that those who found it “scarier” had higher anxiety levels.

The third study found that by showing students videos or pictures from the dissection room, it reduces their anxiety levels when completing their first dissection.

Although students experience different emotions when they begin human dissections, anxiety is the most important. Anxiety was even one of the reasons for removing cadaver dissections from teaching practices (Aziz et al.,2002). So, to answer the question, yes, it is scary, and it can be challenging at times. But without this experience, how will it help future doctors when anatomy is so important?

This study proved that most effective solution is gradual exposure before dissecting a cadaver for the first time. Students should also be taught to have an ethical and humanistic approach to the cadaver. We should remember that “The human body is the most complex system ever created. The more we learn about it, the more appreciation we have about what a rich system it is.”- Bill Gates.

References:

Arráez‐Aybar, L.A., Casado‐Morales, M.I. and Castaño‐Collado, G., 2004. Anxiety and dissection of the human cadaver: an unsolvable relationship?. The Anatomical Record Part B: The New Anatomist: An Official Publication of the American Association of Anatomists, 279(1), pp.16-23.

Aziz MA, McKenzie JC, Wilson, JS, Cowie RJ, Ayeni SA, Dunn BK. 2002. The human cadaver in the age of biomedical informatics. Anat Rec (New Anat) 269:20–32.

Bastos LAM, Proenc¸a MA. 2000. A pra´ tica anato´mica e a formac¸a˜o me´dica. Pan Am J Public Health 7:395–402.

Fox RC. 1979. Essays in medical sociology: journeys into the field. New York: John Wiley and Sons.

Penney JC. 1985. Reactions of medical students to dissection. J Med Educ 60:58–60.

The Prevalence of Diabetes on Polycystic Ovarian Syndrome Patients

by Kaylene Baron

Polycystic Ovarian Syndrome (PCOS) is a disease that results in enlarged ovaries due to the ovaries being covered with cysts [2]. These cysts cause hormonal imbalances. The symptoms of PCOS will vary in degree from one person to another. But, for the most part, these are symptoms: being overweight or obese, few or no periods, irregular menstrual cycle, prone to acne, hirutism (excess body hair) on the face, breasts, insides of the legs as well as mood swings. What makes PCOS such a devasting disease, is that a woman’s fertility is questionable. (Obviously seeing that it is the ovaries we are talking about here). This is due to her irregular menstrual cycle and also no ovulation. This makes conception (falling pregnant) as well as pregnancy (being able to carry the baby to term-in other words, for the full 9 months) difficult [2]. But for me, what makes PCOS devasting is the fact that these hormonal imbalances also have an impact on your metabolism. This increases a woman’s chance of developing diabetes and heart disease [2]. This will be the focus of this blog post.  

To put this situation in a South African context, let me give you some statistics. According to an article in the South African Journal of Obstetrics and Gynaecology, [3]. the condition affects 15–20% of women in their childbearing years and is also linked to 40% of female infertility cases in South Africa. To date, there is no set cause for PCOS much less a cure. I am going to discuss an article with you that investigated the risk of PCOS patients having diabetes [1].

They performed this study by doing the following: Subjects were recruited from the diabetes clinic population (2500 patients) of The Middlesex Hospital. Various criteria were used to determine who is eligible for this study, this total later came down to 38. In subjects with regular menstrual cycles, studies were carried out during the follicular phase (i.e., the stage where menstruation takes place followed by the maturing of the egg until ovulation). Investigations were performed at random in those with marked oligomenorrhoea or amenorrhoea. Body mass index was calculated as weight/height2 (kg/m2). The waist circumference was taken at the level of the umbilicus, the hip circumference was taken at the level of the pubis symphysis to determine the waist/hip ratio. The pelvic ultrasounds were performed to confirm if a woman has polycystic ovaries or not. Fasting blood samples were drawn to test the levels of the various reproductive hormones as well as insulin levels [1].

From the results obtained, eighty-two per cent (31 out of 38) of the women studied had ultrasonographic evidence of polycystic ovaries. The influence of insulin on ovarian function in the group of women with PCO was further analysed using correlations between metabolic parameters and serum androgen concentrations. Body mass index was positively correlated with leptin and total testosterone. Ovarian volume was positively correlated with fasting insulin, androstenedione, total testosterone, body mass index, waist: hip ratio and negatively associated with SHBG [1].

From this study, we can conclude that women with PCOS have higher androgens (male hormones) than women with no PCOS. The impact of this results in a higher BMI and a higher waist: hip ratio. A woman who has uncontrolled weight gain ends up having heart disease and insulin resistance which later gives rise to diabetes.

References:

  1. Conn, JJ., Jacobs, HS., and Conway, GS. 2000. The prevalence of polycystic ovaries in women with type 2 diabetes mellitus. Clinical endocrinology, 52(1):81-86
  2. Glenville, M. 2001. The Natural Health Handbook for Women: The complete guide to women’s health problems and how to treat them naturally. London: Piatkus  
  3. Page, S. 2019. Life healthcare: Get informed about Polycystic Ovary Syndrome.

It’s been a while since the first batch of Covid-19 vaccination was distributed throughout the United Kingdom (UK)

by Koketso Ramotsila

In the United Kingdom, BNT162b2 mRNA and ChAdOx1 nCOV-19 adenoviral vector vaccines have been swiftly carried out. In their healthcare worker (HCW) cohort study of staff receiving regular asymptomatic testing, they identified some variables related with vaccination coverage for both vaccines and demonstrated the immunization efficacy of the BNT162b2 mRNA vaccine.

This SIREN study arose back in December 2020 when infections were flooding at the UK. The SIREN project is basically a prospective cohort study including publicly financed hospitals and their employees.

At two-week intervals, baseline risk factors, vaccination status (from 8-Dec-2020 to 2-Feb-2021), and symptoms were documented, as well as all SARS-CoV-2 polymerase chain reaction (PCR) and antibody test findings.

A Poisson distribution was used in a mixed effect model. To an extent they evaluated the effects of the BNT162b2 vaccination on all infections, a mixed effect proportional hazards frailty model with a Poisson distribution which was used to compute hazard ratios to compare time to infection in unprotected and vaccinated patients. We understand that a Poisson distribution is a probability distribution that can be used to show how many times an event is likely to occur within a specified period of time.

On May 2, 2021, vaccine coverage was 89 percent. Prior infection, being under 35 years old, being from a minority ethnic group, porters/security guards, or a midwife were all linked to much poorer coverage. The BNT162b2 vaccination successfully protects both symptomatic and asymptomatic illness, according to a research. This group was vaccinated while B1.1.7 was the prevalent variation in circulation, demonstrating efficacy against it. Even fans are able occupy football matches in the UK. Did the available vaccines in South Africa produce similar successful results?

References:

Hall V, Foulkes S, Saei A, et al. Effectiveness of BNT162b2 mRNA vaccine against infection and COVID401 19 vaccine coverage in healthcare workers in England, multicentre prospective cohort study (the SIREN 402 study).

Antifungal Cross-Resistance and the need for an antifungal resistance database

by Oscar Megan

Triazole resistance in Aspergillus fumigatus is an emerging health problem. This fungus is a major cause of invasive fungal infections in immunocompromised individuals, and has spread significantly in the last decades (Zhang et al., 2017). There are two main classes of antifungals used to treat this fungal infection: (1) Medical triazoles, used for cases of human infection (For example, Itraconazole and posaconazole). (2) Sterol-Biosynthesis Inhibitors used as agricultural fungicides (Used in the treatment of wood fences, or decaying plant matter). There are two presumed paths to medical triazole resistance: (1) Through selection pressure of triazole use
when treating patients. (2) Through selection pressure of non-medical SIs used in the environment. Put simply, Aspergillus fumigatus is also presumed to develop medical triazole resistance when only exposed to the non-medical sterol-biosynthesis inhibitors (SIs).

In a 2017 study (Zhang et al., 2017), researchers sought out to determine the level, and speed at which this cross-resistance is developed in Aspergillus fumigatus. Evolved Aspergillus fumigatus samples were used from a previous study which tested for SI resistance for five different agricultural fungicides. In the 2017 study, these evolved lineages were then exposed to three medical Triazoles (1)itraconazole (2)posaconazole (3) voriconazole over seven weeks
at varying concentrations to determine the minimal inhibitory concentration (MIC) for the evolved lineages.

These figures show the change in relative MIC over time. Plot (a) shows the results of the previous study, plots (b), (c) and (d) show the changes when exposed to the three medical Triazoles.

The observable trend from these figures is that, over seven weeks the SI resistant strains develop medical triazole resistance (because of the increasing minimal inhibitory concentration). After whole-genome sequencing the now medical triazole resistant lineages, it was found that there were no structural changes needed to develop this resistance. Put simply, by developing SI resistance Aspergillus fumigatus also developed resistance to medical triazoles.

This finding is of major concern. If sterol-biosynthesis inhibitors are overused in agriculture or elsewhere, Aspergillus fumigatus could develop medical triazole resistance through selection pressures.

A similar phenomenon in antibiotics resistance has been observed in recent decades. To combat this, the antibiotic resistance database Comprehensive Antibiotic Resistance Database or CARD, was funded. CARD was made so that findings relevant to resistance could be made publicly available. Currently, there are no large-scale, well funded antifungal resistance databases, and the findings of this 2017 study highlight the growing need to fund such a database.

References:

Zhang, J., van den Heuvel, J., J. M. Debets, A., E. Verweij, P., J. G. Melchers, W., J. Zwaan, B. and E. Schoustra, S., 2017. Evolution of cross-resistance to medical triazoles in Aspergillus fumigatus through selection pressure of environmental fungicides.

The Role of Kisspeptin in Immune Tolerance Formation During Pregnancy

by Katleho Matlatse

Have you ever wondered why pregnancy loss is an experience many women are and have been facing for centuries? But the more persistent question is why women experience recurrent pregnancy loss? and why, after the development of new technologies and novel knowledge, the incidence of it occurring is not reducing?

1-2% of women will experience recurrent pregnancy loss (Ford & Schust, 2009). Pregnancy loss, also known as loss of clinical pregnancy or miscarriage, is defined as the loss of fetus before the 20 completed weeks of gestational age. Recurrent pregnancy loss (RPL) occurs when women experience three or more consecutive miscarriages. When the etiology is often unknown or spontaneous, this is classified as idiopathic recurrent miscarriage (IRM). An imbalance in placental hormones and or immune dysregulation may give rise to implantation failure and eventually lead to pregnancy loss. The tumour metastasis suppressor decapeptide, kisspeptin, and its receptor, GPR54, are expressed in the placenta and are thought to play an important role in
embryo implantation, early placentation, and trophoblast invasion. Furthermore, kisspeptin regulates the behavior of regulatory lymphocytes thereby altering concentrations of IL-10 and IL-17A, events key for maternal immune tolerance.

If Kisspeptin increases the formation of aTreg (adaptive T regulatory) cells, would an increase occur in pro-inflammatory ( IL-17A) and anti-inflammatory (IL-10)? What would the mode of mechanism look like?

The study hypothesizes that in pregnancy, the expression of kisspeptin influences that of anti-inflammatory and pro-inflammatory cytokines which are key in setting maternal immune tolerance. To achieve this, the authors collected blood samples from nonpregnant women of reproductive age (from 23-37 years of age) but compared that data with peripheral blood samples of women in trimester I, II and II. The authors performed extraction of peripheral blood mononuclear cells (PBMCs) from blood samples, followed by immunomagnetic separation methods to extract CD4+ T cells. The cells
were induced with different concentrations of Kisspeptin, IDO and Lipopolysaccharide and incubated. To induce aTreg cells, the authors introduced cytokine specific monoclonal antibodies along with kisspeptin, IDO and liposaccharide (LPS) stimulation followed by ELISA tests (which detect protein expression) and Flow cytometry to evaluate lymphocyte phenotype.

Research done before this study suggested that increasing the production of aTreg cells, by increasing the production of anti-inflammatory cytokine IL-10 and reducing the production of IL-17A, a pro-inflammatory cytokine enhances immune tolerance. This ultimately reduces the immune response. Inducing aTreg cells with Kisspeptin, significantly increases the formation of increased CD4+ T cells at different concentrations during trimester I, II and III. This study discovered that aTreg cells, when induced with the hormone kisspeptin, enhanced the production of IL-10, and significantly reduces the production of IL-17A (prevents differentiation of Th17 lymphocytes) by CD4+ T lymphocytes of peripheral blood of women. An increase in anti-inflammatory cytokines, reduces immune response. Therefore, kisspeptin has shown to increase immune tolerance between the maternal-fetal interface (from the maternal body to the fetus) antigens, which ultimately determines the outcome of
pregnancy. What is interesting in this paper is that it stimulates the idea that pregnancy loss is not just a result of environmental factors, genetics, but rather hormone dysregulation can play a part. I believe more studies need to be done on hormone regulation between the maternal-fetal interface and how we can significantly reduce pregnancy loss.

References
Ford, H. B. & Schust, D. J., 2009. Recurrent Pregnancy Loss: Etiology, Diagnosis, and Therapy. Obstetrics and Gynecology, 2(2), pp. 76-83.
Gorbunova, O. L. & Shirshev, S. V., 2014. The role of Kisspeptin in Immune Tolerane Formation during Pregnancy. Volume 457.

Gaba Regulates Synaptic Integration of Newly Generated Neurons in the Adult Brain

by Zamazimba Madi

Adult neurogenesis is the process in which neurons are generated from neural stem cells in the adult, it is a form of structural neuroplasticity and emphasizes regenerative ability of the adult mammalian brain​. It is known that neuronal activity regulates adult neurogenesis and, new neurons contribute to specific brain functions​. It is unknown how the integration of these new neurons into the existing functional neuronal circuits is regulated​. Expect to see that newborn granule cells are tonically activated by ambient GABA (γ-aminobutyric acid, an inhibitory neurotransmitter in the central nervous system) before sequential innervation by GABA- and glutamate-mediated synaptic inputs​. GABA initially depolarizes newborn neurons owing to their high cytoplasmic chloride content​. In vivo, GABA-induced depolarization converted into hyperpolarization in newborn neurons results in marked defects in synapse formation and dendritic development​. The purpose of this study was to establish the role of GABA in the synaptic integration and proposes a mechanism for the regulation of adult neurogenesis​.

DEVELOPMENT OF NEWBORN CELLS IN THE ADULT MICE

Thus, new-born cells are tonically activated by ambient GABA before any detectable phasic or synaptic activation, and we can conclude that new-born cells in the adult brain, as in neonates, first receive tonic GABA activation, then GABA-mediated synaptic inputs and finally glutamate-mediated synaptic inputs.

NATURE OF GABA-INDUCED ACTIVATION IN NEWBORN CELLS IN THE ADULT BRAIN​

GABA initially depolarizes new-born cells in the adult brain.  Tonic GABA activation led to hyperpolarization of NKCC1- shRNA [sodium (Na), potassium (K), chloride (Cl) co-transporter 1- short/small hairpin RNA (an artificial RNA molecule with a tight hairpin turn that can be used to silence target gene expression via RNA interference its expression in these cells is usually achieved through the delivery of plasmids or viral or bacterial vectors. See image (Sliva & Schnierle, 2010)) expressing cells in contrast to depolarization on the control new-born cells. GABA depolarizes new-born cells during initial development due to their high chloride ion concentration from the expression of NKCC1. Therefore, tonic GABA activation not only depolarizes new-born cells but is also the bulk of GABA-induced activation during initial integration when phasic or synaptic GABA activation is weaker than tonic activation or does not exist.

SYNAPTIC INTEGRATION OF NEWBORN CELLS IN THE ADULT BRAIN

There are defects in the formation of GABA-mediated synapses by NKCC1-shRNA-expressing cells. Results show that postsynaptic currents and spontaneous synaptic currents were detected in NKCC1-shRNA-expressing cells halfway through the experiment, and the percentage of cells recorded with postsynaptic currents was largely reduced two weeks later.  Therefore, there were no general defects in receptor expression at the synapses.

DENDRITIC DEVELOPMENT OF NEWBORN CELLS IN THE ADULT BRAIN

NKCC1-shRNA expressing cells had marked defects in dendritic arborization i.e., total dendritic length, branch number and complexity were reduced.  Therefore, GABA-induced depolarization regulates the dendritic development of new-born neurons in the adult brain.

In conclusion, the integration of newborn neurons into existing functional circuitry involves tonic GABA activation to GABA-mediated synaptic innervation, then glutamate-mediated synaptic innervation​. GABA initially depolarizes newborn neurons, as it would neonatal neurons because of their high cytoplasmic chloride ion content from NKCC1 expression​. Converting GABA-induced excitation into inhibition leads to marked defects in the development of GABA- and glutamate-mediated synapses and dendritic development in newborn neurons​. Tonic GABA activation depolarizes newborn neurons and phasic activation non-existent or weaker​. A possible mechanism was proposed for activity-dependent regulation of adult neurogenesis i.e., through new neurons that sense neuronal network activities through local ambient GABA levels before receiving synaptic innervations​. The results from this experiment can be applied stem cell cell-replacement therapy for neurodegenerative diseases​.

REFERENCES

Ge, S., Goh, E.L., Sailor, K.A., Kitabatake, Y., Ming, G.L. and Song, H., 2006. GABA regulates synaptic integration of newly generated neurons in the adult brain. Nature439(7076), pp.589-593.

Sliva, K. and Schnierle, B.S., 2010. Selective gene silencing by viral delivery of short hairpin RNA. Virology journal7(1), pp.1-11.

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