Kinematic differences between left- and right-handed cricket fast bowlers during the bowling action

Background

Despite differences between left- and right-handed athletes in other sports, minimal evidence exists regarding biomechanical similarities and differences between left- and right-handed cricket fast bowlers performing an equivalent task.

Objectives

This study aimed to compare the kinematics between left and right-handed fast bowlers performing an equivalent task (i.e. bowling 'over the wicket' to a batter of the same handedness as the bowler).

Methods

Full body, three-dimensional kinematic data for six left-handed and 20 right-handed adolescent, male, fast bowlers were collected using the Xsens inertial measurement system. Time-normalised joint and segment angle time histories from back foot contact to follow-through ground contacts were compared between groups via statistical parametric mapping. Whole movement and subphase durations were also compared.

Results

Left-handed players displayed significantly more trunk flexion from 49%-56% of the total movement (ball release occurred at 54%; p = 0.037) and had shorter back foot contact durations on average (0.153 vs 0.177 s; p = 0.036) compared to right-handed players.

Conclusion

Left- and right-handed bowlers displayed similar sagittal plane kinematics but appeared to use non-sagittal plane movements differently around the time of ball release. The kinematic differences identified in this study can inform future research investigating the effect of hand dominance on bowling performance and injury risk.

The core of performance in adolescent cricket pace bowlers: Trunk muscle stability, maybe, but not strength-endurance and thickness

Background

The trunk connects the upper and lower limbs and transfers energy during movement. Exploring the role of the trunk muscles in bowling performance affords us the opportunity to uncover potential mechanisms to improve bowling performance.

Objectives

To investigate the association between bowling performance and trunk muscle stability, strength-endurance and thickness in adolescent pace bowlers.

Methods

Adolescent pace bowlers participated in this cross-sectional study. Trunk muscle stability was measured using Sahrmann's Stability Scale, strength-endurance using the Bourbon Trunk Muscle Strength Test and thickness of the abdominal wall and lumbar multifidus muscles using ultrasound imaging.

Results

Forty-six pace bowlers with a mean age of 15.9 ±1.2 years participated. The average ball release speed was 109.2±11.8 km.h^-1. This measurement was higher in level four of stability than in level two (mean difference 22.2 ± SD 6.8 km.h^-1; p= .018). No link between ball release speed and strength-endurance could be found. Multiple correlations of moderate strength (r > 0.4) exist between ball release speed and absolute trunk muscle thickness with height and weight as confounding factors. The relationship between accuracy and the trunk muscle variables investigated in this study is weak.

Conclusion

Bowlers with better trunk muscle stability bowled faster than those with a lower level of trunk stability, irrespective of their age, height and weight. Trunk muscle thickness correlated with ball release speed; however, confounding factors such as height and weight play a role and therefore, findings need to be interpreted with caution.

The cycle ergometer test is not a reliable alternative to the countermovement jump in the assessment of power output

Background

Rugby union is a physically demanding collision sport that requires optimal neuromuscular function for maximal power output, with mechanical power an integral component of performance. Peak power (P_p) and relative P_p are parameters of neuromuscular function commonly assessed through the countermovement jump (CMJ) as a measure of fatigue. The Wattbike cycle ergometer test (CET) is a non-load bearing method of evaluating lower limb power. The cost-effective CET could therefore offer a viable alternative to the CMJ.

Objectives

This study aimed to determine the concurrent validity of the CMJ and CET.

Methods

Thirty-eight professional rugby union players performed twelve CMJs on a force platform with four loads (bodyweight: BW-CMJ; 20kg: 20-CMJ; 40kg: 40-CMJ and 60kg: 60-CMJ) and a six second peak power (6PPO) CET assessment on a Wattbike ergometer.

Results

CMJ power outputs were [BW-CMJ: P_p - 3101±648 W; 20-CMJ: P_p - 2724±513 W; 40-CMJ: P_p - 2490±496 W; 60-CMJ: P_p - 2238±366 W] and CET [P_p - 1310±161 W]. None of the CMJ-P_p values showed relationships with any CET power variables. Large (r = 0.51-0.63; p = 0.000 - 0.001) relationships were found to be between relative CMJ and relative CET power outputs. Bland-Altman plots, which were used to determine the level of agreement between the two assessments, showed the agreement between the tests was poor.

Conclusion

Though positive relationships existed between relative CMJ and relative CET power variables, analyses of the level of agreement in the Bland-Altman plots suggest that the two power assessment methods are not interchangeable measures of power.

A prevalence of running-related injuries among professional endurance runners in the Rift Valley, Kenya

Background

Injuries related to endurance running have attracted attention as the sport has become more competitive, and as athletes seek to improve their performance. Consequently, endurance runners are increasingly becoming more susceptible to lower extremity running injuries.

Objectives

The aim of this study was to establish the prevalence of running-related injuries among professional endurance runners in the Rift Valley, Kenya.

Methods

We used a cross-sectional survey design targeting professional endurance runners who had participated in both local and international running competitions. The sample size consisted of 209 respondents selected through stratified and simple random sampling techniques, of which 167 participated in the study. A self-administered questionnaire was used to collect data on the prevalence of injuries among the endurance runners. The data were analysed using descriptive statistics.

Results

The prevalence of running injuries was 63% (n=106). The prevalence among males (n=64; 69%) was higher in comparison with that of females (n=42; 57%). The posterior thigh was the most common site for injuries among the athletes (n=87; 52%), followed by the lower back (n=78; 47%) and ankle (n=63; 38%).

Conclusion

The prevalence of running-related injuries was high among professional Kenyan endurance runners compared to other populations. These findings therefore form the basis of future research to explore the mechanisms behind the injuries and the feasibility of targeted injury prevention programmes.

The epidemiology of injury and illness amongst athletes at the Indian Ocean Island Games, Mauritius, 2019

Background

The Indian Ocean Island Games is a multi-sport event that occurs every four years and includes athletes from seven islands of the Indian Ocean, namely, Comoros, Reunion, Mayotte, Madagascar, Maldives, Seychelles, and Mauritius.

Objectives

This study aims to describe the injury and illness epidemiology of the athletes participating during the 2019 Indian Ocean Islands Games.

Methods

This prospective cohort study recorded injury and illness cases from athletes who competed in these Games. All medical physicians received detailed instructions and training on data collection using an injury report form. All athletes (minors and adults) who provided consent, or consent given from the minors' guardians, were included in this study. Athletes who did not provide consent for this study were excluded.

Results

Athletes (n = 1 521; 531 women and 990 men) reported 160 injuries (injury incidence rate of 11%) and 85 illnesses (illness incidence rate of 6%). The percentage of distribution of injuries were highest in football and basketball. Most injuries occurred during competition, compared with training, joint sprains were the most common type of injury (28%), followed by muscle strains (19%). Men suffered most of the injuries (79% vs. 21% for women). Similarly, men sustained more illnesses than women (57% vs. 43%). Most illnesses affected the respiratory system (67%), and infection was the most common cause of illness (84%) in participating athletes.

Conclusion

These findings are similar to previous events in other parts of the world. However, unique ailments, not previously reported on, were discovered. Epidemiological data from this study can be inferred to athletes who compete in similar multi-sport events in the Indian Ocean region.

Injury prevention knowledge, beliefs, and practices among women's football teams in South Africa

Background

Numerous factors account for injury prevention or lack thereof in any team setting. With the increasing burden of injuries in women's football, and limited human resources accessible in sub-Saharan Africa, it is important to investigate the ways in which standardised injury prevention practices can be achieved.

Objectives

The study aimed to evaluate injury prevention knowledge, beliefs, and practices in women's football teams in the University Sport South Africa (USSA) Football League in Gauteng Province, South Africa.

Methods

A cross-sectional self-administered survey was conducted among women's football teams registered to participate in the USSA Football League in South Africa's Gauteng Province.

Results

A total of 107 respondents participated in the study, which included both players (n=98; 92%) and their support staff (n=9; 9%). The median (interquartile range) age of the participants was 22 (20-25) years. In the population sampled, 36% of the participants perceived that they had adequate knowledge of injury prevention practices in football, while others felt they had limited knowledge of the basic injury prevention programmes (IPPs). The results also indicated that the injury prevention practices of coaches (93%) and their beliefs in this regard (70%) are sufficient for achieving the basic injury prevention goals. Most of the respondents (89%) indicated that a medical support system is important in attaining the goals of injury prevention.

Conclusion

Members of women's teams in the USSA Football League have recognised limited knowledge about the basic IPPs, while they do employ some of the basic injury prevention practices in football. These practices could be influenced by the beliefs of the coaches and the players, and most of them believe that IPPs are important. It is essential as key stakeholders that coaches' and players' education and knowledge of injury prevention strategies should be considered as an integral part of the process to succeed. It should be strongly highlighted and implemented, thus augmenting the credibility, trust and compliance for IPPs in the sport.

Dopaminergic and serotonergic changes in rabbit fetal brain upon repeated gestational exposure to diesel engine exhaust

Limited studies in humans and in animal models have investigated the neurotoxic risks related to a gestational exposure to diesel exhaust particles (DEP) on the embryonic brain, especially those regarding monoaminergic systems linked to neurocognitive disorders. We previously showed that exposure to DEP alters monoaminergic neurotransmission in fetal olfactory bulbs and modifies tissue morphology along with behavioral consequences at birth in a rabbit model. Given the anatomical and functional connections between olfactory and central brain structures, we further characterized their impacts in brain regions associated with monoaminergic neurotransmission. At gestational day 28 (GD28), fetal rabbit brains were collected from dams exposed by nose-only to either a clean air or filtered DEP for 2 h/day, 5 days/week, from GD3 to GD27. HPLC dosage and histochemical analyses of the main monoaminergic systems, i.e., dopamine (DA), noradrenaline (NA), and serotonin (5-HT) and their metabolites were conducted in microdissected fetal brain regions. DEP exposure increased the level of DA and decreased the dopaminergic metabolites ratios in the prefrontal cortex (PFC), together with sex-specific alterations in the hippocampus (Hp). In addition, HVA level was increased in the temporal cortex (TCx). Serotonin and 5-HIAA levels were decreased in the fetal Hp. However, DEP exposure did not significantly modify NA levels, tyrosine hydroxylase, tryptophan hydroxylase or AChE enzymatic activity in fetal brain. Exposure to DEP during fetal life results in dopaminergic and serotonergic changes in critical brain regions that might lead to detrimental potential short-term neural disturbances as precursors of long-term neurocognitive consequences.

Repeated gestational exposure to diesel engine exhaust affects the fetal olfactory system and alters olfactory-based behavior in rabbit offspring

BACKGROUND

Airborne pollution, especially from diesel exhaust (DE), is known to have a negative effect on the central nervous system in exposed human populations. However, the consequences of gestational exposure to DE on the fetal brain remain poorly explored, with various effects depending on the conditions of exposure, as well as little information on early developmental stages. We investigated the short-term effects of indirect DE exposure throughout gestation on the developing brain using a rabbit model. We analyzed fetal olfactory tissues at the end of gestation and tested behaviors relevant to pups' survival at birth. Pregnant dams were exposed by nose-only inhalation to either clean air or DE with a content of particles (DEP) adjusted to 1 mg/m³ by diluting engine exhaust, for 2 h/day, 5 days/week, from gestational day 3 (GD3) to day 27 (GD27). At GD28, fetal olfactory mucosa, olfactory bulbs and whole brains were collected for anatomical and neurochemical measurements. At postnatal day 2 (PND2), pups born from another group of exposed or control female were examined for their odor-guided behavior in response to the presentation of the rabbit mammary pheromone 2-methyl-3-butyn-2-ol (2MB2).

RESULTS

At GD28, nano-sized particles were observed in cilia and cytoplasm of the olfactory sensory neurons in the olfactory mucosa and in the cytoplasm of periglomerular cells in the olfactory bulbs of exposed fetuses. Moreover, cellular and axonal hypertrophies were observed throughout olfactory tissues. Concomitantly, fetal serotoninergic and dopaminergic systems were affected in the olfactory bulbs. Moreover, the neuromodulatory homeostasis was disturbed in a sex-dependent manner in olfactory tissues. At birth, the olfactory sensitivity to 2MB2 was reduced in exposed PND2 pups.

CONCLUSION

Gestational exposure to DE alters olfactory tissues and affects monoaminergic neurotransmission in fetuses' olfactory bulbs, resulting in an alteration of olfactory-based behaviors at birth. Considering the anatomical and functional continuum between the olfactory system and other brain structures, and due to the importance of monoamine neurotransmission in the plasticity of neural circuits, such alterations could participate to disturbances in higher integrative structures, with possible long-term neurobehavioral consequences.

A simulated rugby match protocol induces physiological fatigue without decreased individual scrummaging performance

Background: A rugby union game consists of 80 minutes of strenuous exertion. Forwards are required to participate in the arduous activity of scrummaging throughout a game.Objectives: The purpose of this study was to identify whether rugby-match simulated fatigue modified individual scrummaging technique and reduced performance.Methods: Twelve forwards (body mass 106.2±13.3 kg; stature 179.5±8.4 cm) had individual scrum kinetics and kinematics assessed prior to and following a protocol that simulated a rugby match. The simulated rugby match protocol required participants to run at various velocities and perform rugby specific tasks. Rating of Perceived Exertion (RPE) was assessed using a 6-20 Borg scale and Visual Analogue Scale (VAS). Blood lactate, heart rate and RPE were measured prior to, at mid-point and after the simulated game, while markers of muscle damage (blood creatine kinase activity (CK) and urea) were measured prior to and following the protocol.Results: RPE (p<0.0001) and VAS (p<0.0001) showed significant increases between the pre- and post-simulation values. Of the physiological markers, heart rate (p<0.0001) and blood urea concentration (p=0.004) increased following the match simulation. No significant differences were observed for blood CK (p=0.281), individual scrummaging forces (p=0.433) or in the kinematic variables following the protocol. While physiological fatigue and subjective ratings of physiological fatigue may develop during a rugby simulation, no differences were observed in peak forces or in body kinematics at peak force.Conclusion: Physiological fatigue does not influence individual scrummaging performance and technique.

A Large-Scale Automated Method for Hepatocyte Isolation: Effects on Proliferation in Culture

Large-scale sterile methods for isolating hepatocytes are desirable for the development of bioartificial liver support systems. In this study the traditional centrifuge method was compared with the use of a Baylor Rapid Autologous Transfusion (BRAT) machine for isolating large quantities of porcine hepatocytes. After isolating hepatocytes, the methods were evaluated in terms of cell viability and yield per liver, proliferation over 7 days, and the effects on the cell cycle using the trypan blue exclusion test, conventional phase-contrast light microscopy, the lactate to pyruvate ratio, the leakage of lactate dehydrogenase (LD) and aspartate aminotransferase (AST), lidocaine clearance, albumin production, and flow cytometry. With the centrifuge method the mean cell viability was 92.5%, while with the BRAT method the viability was 95.9%. The minimal cell yields with the BRAT procedure were 7.3 × 109 for 250-ml centrifuge bowls and 2.8 × 109 for 165-ml bowls, which compares well with that found by other authors. Because the same initial procedures were employed in both methods the total hepatocyte yield per liver was comparable. Flow cytometry confirmed that the proliferation of hepatocytes was facilitated by oxygenation during the isolation procedure. The recovery of hepatocytes in culture following isolation was similar after either method. Daily microscopic investigation indicated that cytoplasmic vacuolization and granularities were present after either procedure and these disappeared following 3–4 days of culturing. Flow cytometry indicated that the hepatocyte cell cycle was similar after either method; at 7 days the profile indicated that the cells were still proliferating. Trends in the lactate to pyruvate ratio and the leakage of LD and AST indicated that the functional polarity of hepatocytes was regained after approximately 3 days. Lidocaine clearance at 4 days indicated that the cytochrome P450 system was active, while significant albumin production was apparent at day 5. The benefit of using BRAT technology in hepatocyte isolation lies in guaranteed sterility, convenience, speed, and the ability to oxygenate media and cell suspensions during the procedure.

[Feasibility study for Intercept platelets]

During 3 months, platelet concentrates prepared by "Établissement français du sang Pyrénées-Méditerranée" (Blood bank) were treated with the Intercept process (CERUS^©). This study primarily aimed to measure the organizational impact of this technology on transfusion chain. The introduction of Intercept did not raise any major difficulties, but required some adaptations upstream from the deployment. Prior information of health care institutions and physician was essential to anticipate the practical changes, including the prescription of platelet concentrates (CMV negative, irradiation). This study allowed to analyze also the transfusion consequences for patients, in the form of observational studies. The patients transfused with platelet concentrates treated with Intercept received more platelet concentrates (+12.9%), less rich in platelets (-12.8%), the cumulated quantity of platelet being stable.

The association between loss of ankle dorsiflexion range of movement, and hip adduction and internal rotation during a step down test

A pattern of excessive hip adduction and internal rotation with medial deviation of the knee has been associated with numerous musculo-skeletal dysfunctions. Research into the role that ankle dorsiflexion (DF) range of motion (ROM) play in lower limb kinematics is lacking. The objective of this cross-sectional, observational study was to investigate the relationship between ankle DF ROM, and hip adduction and hip internal rotation during a step-down test with and without heel elevation in a healthy female population. Hip and ankle ROM was measured kinematically using a ten-camera Optitrack motion analysis system. Thirty healthy female participants (mean age = 20.4 years; SD = 0.9 years) first performed a step-down test with the heel of the weight bearing foot flat on the step and then with the heel elevated on a platform. Ankle DF, hip adduction and hip internal rotation were measured kinematically for the supporting leg. Participants who had 17° or less of ankle DF ROM displayed significantly more hip adduction ROM (p = 0.001; Cohen's d effect size = 1.2) than the participants with more than 17° of DF during the step-down test. Participants with limited DF ROM showed a significant reduction in hip adduction ROM during the elevated-heel step-down test (p = 0.008). Hip internal rotation increased in both groups during the EHSD compared to the step-down test (p > 0.05) Reduced ankle DF ROM is associated with increased hip adduction utilised during the step-down test. Ankle DF should be taken into account when assessing patients with aberrant frontal plane lower limb alignment.

The role of oxytocin in male and female reproductive behavior

Oxytocin (OT) is a nonapeptide with an impressive variety of physiological functions. Among them, the 'prosocial' effects have been discussed in several recent reviews, but the direct effects on male and female sexual behavior did receive much less attention so far. As our contribution to honor the lifelong interest of Berend Olivier in the control mechanisms of sexual behavior, we decided to explore the role of OT in the present review. In the successive sections, some physiological mechanisms and the 'pair-bonding' effects of OT will be discussed, followed by sections about desire, female appetitive and copulatory behavior, including lordosis and orgasm. At the male side, the effects on erection and ejaculation are reviewed, followed by a section about 'premature ejaculation' and a possible role of OT in its treatment. In addition to OT, serotonin receives some attention as one of the main mechanisms controlling the effects of OT. In the succeeding sections, the importance of OT for 'the fruits of labor' is discussed, as it plays an important role in both maternal and paternal behavior. Finally, we pay attention to an intriguing brain area, the ventrolateral part of the ventromedial hypothalamic nucleus (VMHvl), apparently functioning in both sexual and aggressive behavior, which are at first view completely opposite behavioral systems.

Static and dynamic balance ability, lumbo-pelvic movement control and injury incidence in cricket pace bowlers

OBJECTIVES

This study aimed to establish the difference in lumbo-pelvic movement control, static and dynamic balance at the start and at the end of a cricket season in pace bowlers who sustained an injury during the season and those who did not.

DESIGN

This is a longitudinal, observational study.

METHODS

Thirty-two, healthy, injury free, male premier league fast, fast-medium and medium pace bowlers between the ages of 18 and 26 years (mean age 21.8 years, standard deviation 1.8 years) participated in the study. The main outcome measures were injury incidence, lumbo-pelvic movement control, static and dynamic balance ability.

RESULTS

Fifty-three percent of the bowlers (n=17) sustained injuries during the reviewed cricket season. Lumbo-pelvic movement control tests could not discriminate between bowlers who sustained an injury during the cricket season and bowlers who did not. However, performance in the single leg balance test (p=0.03; confidence interval 4.74-29.24) and the star excursion balance test (p=0.02; confidence interval 1.28-11.93) as measured at the start of the season was better in bowlers who did not sustain an injury during the season.

CONCLUSIONS

The improvement in the lumbo-pelvic movement control and balance tests suggests that the intensity and type of physical conditioning that happens throughout the season may have been responsible for this improvement. Poor performance in the single leg balance test and the star excursion balance test at the start of the cricket season may be an indication that a bowler is at heightened risk of injury.

Side-to-side asymmetry in absolute and relative muscle thickness of the lateral abdominal wall in cricket pace bowlers

Background. The abdominal musculature plays a protective role against lower-back injury. Knowledge of the asymmetry in abdominal wall thickness in healthy, injury-free cricket pace bowlers may provide a useful platform against which pathology could be assessed and the effects of training could be evaluated.Objective. To compare side-to-side differences in absolute muscle thickness and activity of the abdominal musculature and to compare these measurements at the start, with those at the end of a cricket season among a group of amateur pace bowlers.Methods. This was a controlled longitudinal prospective study. Rehabilitative ultrasound imaging was used to assess abdominal muscle thickness in 26 right-handed, injury-free cricket pace bowlers at the start and at the end of a cricket season. Thickness measurements were done at rest, during an abdominal drawing-in manoeuvre (ADIM) and the active straight-leg raise (ASLR) on the left (-L) and right (-R).Results. The absolute thickness of the non-dominant obliquus abdominis internus (OI) was higher than that of the dominant OI at the start (p=0.001; ES=0.87) as well as at the end of the cricket season (p=0.001; ES 1.09). At the start of the season, the percentage change during the ADIM, thus muscle activity, was higher for the non-dominant OI than for the dominant OI (p=0.02; ES=0.51). Absolute thickness of the dominant obliquus abdominis externus (OE) at rest was significantly higher at the end of the season compared with the start of the season (p=0.0001; ES=0.85). During ASLR-R, the activity of the left transversus abdominis (TA) was significantly higher than that of the right TA during ASLR-L (p=0.03) when measured at the end of the season.Conclusion. This study highlights the possible muscle adaptations in absolute muscle thickness and activity as a consequence of the asymmetrical bowling action.

Side-to-side asymmetry in absolute and relative muscle thickness of the lateral abdominal wall in cricket pace bowlers

Background. The abdominal musculature plays a protective role against lower-back injury. Knowledge of the asymmetry in abdominal wall thickness in healthy, injury-free cricket pace bowlers may provide a useful platform against which pathology could be assessed and the effects of training could be evaluated.Objective. To compare side-to-side differences in absolute muscle thickness and activity of the abdominal musculature and to compare these measurements at the start, with those at the end of a cricket season among a group of amateur pace bowlers.Methods. This was a controlled longitudinal prospective study. Rehabilitative ultrasound imaging was used to assess abdominal muscle thickness in 26 right-handed, injury-free cricket pace bowlers at the start and at the end of a cricket season. Thickness measurements were done at rest, during an abdominal drawing-in manoeuvre (ADIM) and the active straight-leg raise (ASLR) on the left (-L) and right (-R).Results. The absolute thickness of the non-dominant obliquus abdominis internus (OI) was higher than that of the dominant OI at the start (p=0.001; ES=0.87) as well as at the end of the cricket season (p=0.001; ES 1.09). At the start of the season, the percentage change during the ADIM, thus muscle activity, was higher for the non-dominant OI than for the dominant OI (p=0.02; ES=0.51). Absolute thickness of the dominant obliquus abdominis externus (OE) at rest was significantly higher at the end of the season compared with the start of the season (p=0.0001; ES=0.85). During ASLR-R, the activity of the left transversus abdominis (TA) was significantly higher than that of the right TA during ASLR-L (p=0.03) when measured at the end of the season.Conclusion. This study highlights the possible muscle adaptations in absolute muscle thickness and activity as a consequence of the asymmetrical bowling action.

Cross-species genetics converge to TLL2 for mouse avoidance behavior and human bipolar disorder

Interspecies genetic analysis of neurobehavioral traits is critical for identifying neurobiological mechanisms underlying psychiatric disorders, and for developing models for translational research. Recently, after screening a chromosome substitution strain panel in an automated home cage environment, chromosomes 15 and 19 were identified in female mice for carrying genetic loci that contribute to increased avoidance behavior (sheltering preference). Furthermore, we showed that the quantitative trait locus (QTL) for baseline avoidance behavior on chromosome 15 is homologous with a human linkage region for bipolar disorder (8q24). Similarly, we now performed comparative analysis on the QTL for avoidance behavior found on chromosome 19 and correspondingly revealed an overlap of the mouse interval and human homologous region 10q23-24, which has been previously linked to bipolar disorders. By means of a comparative genetic strategy within the human homologous region, we describe an association for TLL2 with bipolar disorder using the genome-wide association study (GWAS) data set generated by the Wellcome Trust Case Control Consortium (WTCCC). On the basis of genetic homology and mood stabilizer sensitivity, our data indicate the intriguing possibility that mouse home cage avoidance behavior may translate to a common biochemical mechanisms underlying bipolar disorder susceptibility. These findings pave new roads for the identification of the molecular mechanisms and novel treatment possibilities for this psychiatric disorder, as well as for the validity of translational research of associated psychiatric endophenotypes.

The association between trunk muscle endurance and lumbo-pelvic stability in adolescent low back pain: A cross sectional study

Decreased trunk muscle endurance has been identified as a risk factor for adolescent LBP, and poor lumbo-pelvic stability has been found to be associated with LBP in the adult population. The aim of the study was to investigate the association between adolescent LBP, trunk muscle endurance and poor lumbo-pelvic stability. Design: A cross sectional study. Participants: 80 adolescents in grade 8 to grade 11, aged 12 to 17 years, at three high schools in Gauteng, who agreed to participate in the study. Method: Data was collected by means of a validated questionnaire and physical tests. The active straight leg raise test was used to record the lumbo-pelvic stabilising muscles. The Sorensen, Shirado and side-bridge tests were used to record trunk extensor, flexor and side flexor muscle endurance, respectively. Results: The results revealed a lifetime prevalence of LBP of 82.50%, one year prevalence of 78.80% and point prevalence of 23.80%. Adolescents with LBP demonstrated decreased trunk extensor muscle endurance but increased trunk flexor muscle endurance (p=0.044), compared to non-LBP adolescents. Poor lumbo-pelvic stability was not associated with adolescent LBP, but was associated with decreased extensor trunk muscle endurance (p=0.031). Conclusion: There was an association between trunk flexor muscle endurance and adolescent LBP, and between decreased trunk extensor muscle endurance and poor lumbo-pelvic stability. No association was found between LBP and poor lumbo-pelvic stability.

Inter-examiner reliability when using the Objective Structured Practical Examination (OSPE) mark sheet for physiotherapy practical

The Objective Structured Practical Examination (OSPE) format is used during practical examinations as part of the physiotherapy undergraduate curriculum at the University of the Witwatersrand. Various factors influence inter-examiner reliability and investigating the inter-examiner reliability when using the OSPE can lead to improvement of the examination process. The aim of this study was to establish inter-examiner reliability when using the OSPE mark sheet. Methods: Twelve examiners participated in this study. Thirty-three second year PT students were examined at six stations and by two examiners at each station. The Spearman’s correlation test was used to establish inter-examiner reliability. Results: The general inter-examiner reliability of the OSPE mark sheet was high. There was a high correlation between examiners who had the same level of experience (r=0.79 to r=0.93; p<0.001). The background knowledge section of the OSPE mark sheet showed the greatest inter-examiner reliability (r=0.75 to r=0.91; p<0.001). Discussion: In general, a high inter-examiner reliability was found. Examiners with the same level of experience seemed to generally have better inter-examiner reliability when using the OSPE mark sheet. Furthermore, a well-described, operationalised list of micro-skills also improved inter-examiner reliability. Conclusion: The OSPE mark sheet aids inter-examiner reliability. The use of this method of examination should be encouraged.

Low back pain in physiotherapy students: Prevalence and the association with neuromuscular findings

Background: Physiotherapy students are prone to low back pain (LBP) due to studying and their active involvement in clinical treatment of patients. As a result of pathology, muscle activity is influenced, affecting optimal function of the spine. Method: Physiotherapy students enrolled for 2010 at the University of the Witwatersrand participated in a cross-sectional study. A questionnaire and physical assessment were completed. Results: The study revealed that the lifetime LBP prevalence was 36% among physiotherapy students. Associations with LBP were hours of practical exposure, posterior-anterior mobilisations on L4 (p=0.003) and L5 (p≤0.001) centrally and unilaterally, left lumbar multifidus (LM) cross-sectional area (p=0.02), right obliquus internusabdominis (OI) (p=0.02) and right transversus abdominis (TrA) thickness at rest (p=0.02), as well as the pull of the TrA during contraction on the left (p=0.03). Discussion: Hours of practical exposure may play a role in lumbar pathology. Due to pathology, muscle imbalances of LM, TrA and OI affect the stability of the spine which may lead to recurrences. Conclusion: Practical exposure as well as LM, TrA and OI muscle imbalances were associated with LBP in physiotherapy students. Awareness of the factors associated with LBP while studying at an undergraduate level may lead to better prevention of LBP.

The effect of trigger point therapy and medicine ball exercises vs trigger point therapy and stretching on hip rotational biomechanics of the golf swings

Background: Elite golfers sustain a large number of lumbar spine injuries. Poor rotational biomechanics, which may occur as a result of a shortened iliopsoas muscle, increase the incidence of lumbar spine injuries in golfers. Stretches and medicine ball exercises are often used as part of golf training programmes in an attempt to restore hip flexor length and improve rotational biomechanics. The aim of this study was to ascertain the effect of a combination of trigger point therapy and medicine ball exercises compared to a combination of trigger point therapy and stretching on rotational bio-mechanics of the golf swing. Method: This is a randomised controlled trial consisting of two experimental groups (trigger point therapy and stretching vs. trigger point therapy and medicine ball exercises) and one control group (no intervention). Hip flexor length and 3D biomechanical analysis of the golf swing was performed at baseline and one week later. Results: One-hundred elite male golfers participated in this study. Rotational biomechanics, specifically downswing hip turn in the group that received trigger point therapy combined with medicine ball exercises, showed statistically significant improvement at reassessment compared to the control group (p=0.0328). Conclusion: Rotational biomechanics (downswing hip turn) improved following a combination of trigger point therapy treatment and a one week programme of medicine ball exercises. This is postulated to have occurred through neural reorganisation and not through improved tensile muscle strength. This improvement in rotational biomechanics has the potential to decrease lumbar spine injury incidence in elite golfers. This study advocates the use of trigger point therapy combined with medicine ball exercises in the treatment of golfers with shortened hip flexors.

Neuroprotection in Parkinson's Disease: A Systematic Review of the Preclinical Data

Aim: This study aimed to systematically review the preclinical data of neuroprotective agents for Parkinson’s disease (PD) to support the translation of these compounds.

Methods: The study consisted of two phases. In phase I, Pubmed and Scopus were systematically searched for neuroprotective agents for PD. In phase II, a systematic search was conducted for each substance identified in phase I. Articles were included if they used MPTP, 6-OHDA, rotenone or paraquat injury models.

Results: Phase I led to the identification of 168 putative neuroprotective agents. Eventually ten compounds were included: melatonin, estrogen, nicotine, caffeine, riluzole, curcumin, coenzyme Q10, aspirin, EGCG and resveratrol. Phase II revealed 113 experimental studies and three reviews.

Conclusion: This study clearly depicts the preclinical data of ten promising neuroprotective agents. While some of these compounds have already been tested in clinical use, none of them was studied in an appropriately designed trial to determine a neuroprotective effect. In expectation of qualitatively improved neuroprotection trials, the data from this study provide a firm foundation for future research.

Effects of coffee on driving performance during prolonged simulated highway driving

RATIONALE

Coffee is often consumed to counteract driver sleepiness. There is limited information on the effects of a single low dose of coffee on prolonged highway driving in non-sleep deprived individuals.

OBJECTIVES

The aim of this study was to examine the effects of a single cup of coffee (80 mg caffeine) on simulated highway driving performance.

METHODS

Non-sleep deprived healthy volunteers (n024) participated in a double-blind, placebo-controlled, crossover study. After 2 h of monotonous highway driving, subjects received caffeinated or decaffeinated coffee during a 15-min break before continuing driving for another 2 h. The primary outcome measure was the standard deviation of lateral position (SDLP), reflecting the weaving of the car. Secondary outcome measures were speed variability, subjective sleepiness, and subjective driving performance.

RESULTS

The results showed that caffeinated coffee significantly reduced SDLP as compared to decaffeinated coffee, both in the first (p00.024) and second hour (p00.019) after the break. Similarly, the standard deviation of speed (p0 0.024; p00.001), mental effort (p00.003; p00.023), and subjective sleepiness (p00.001; p00.002) were reduced in both the first and second hour after consuming caffeinated coffee. Subjective driving quality was significantly improved in the first hour after consuming caffeinated coffee (p00.004).

CONCLUSIONS

These findings demonstrate a positive effect of one cup of caffeinated coffee on driving performance and subjective sleepiness during monotonous simulated highway driving.

NPY receptor subtype specification for behavioral adaptive strategies during limited food access

The neuropeptide Y (NPY) system in the brain regulates a wide variety of behavioral, metabolic and hormonal homeostatic processes required for energy balance control. During times of limited food availability, NPY promotes behavioral hyperactivity necessary to explore and prepare for novel food resources. As NPY can act via 5 different receptor subtypes, we investigated the path through which NPY affects different behavioral components relevant for adaptation to such conditions. We tested NPY Y1 and Y2 receptor knockout mice and their wild-type littermate controls in a daily scheduled limited food access paradigm with unlimited access to running wheel. Here we show that NPY Y1 receptor deficient mice lack the expression of appetitive behavior and that NPY Y2 receptors control the level of hyperactive behavior under these conditions. Thus, receptor specificity determines the differential expression of NPY-mediated behavioral adaptations to overcome a negative energy status.

Stress revisited: a critical evaluation of the stress concept

With the steadily increasing number of publications in the field of stress research it has become evident that the conventional usage of the stress concept bears considerable problems. The use of the term 'stress' to conditions ranging from even the mildest challenging stimulation to severely aversive conditions, is in our view inappropriate. Review of the literature reveals that the physiological 'stress' response to appetitive, rewarding stimuli that are often not considered to be stressors can be as large as the response to negative stimuli. Analysis of the physiological response during exercise supports the view that the magnitude of the neuroendocrine response reflects the metabolic and physiological demands required for behavioural activity. We propose that the term 'stress' should be restricted to conditions where an environmental demand exceeds the natural regulatory capacity of an organism, in particular situations that include unpredictability and uncontrollability. Physiologically, stress seems to be characterized by either the absence of an anticipatory response (unpredictable) or a reduced recovery (uncontrollable) of the neuroendocrine reaction. The consequences of this restricted definition for stress research and the interpretation of results in terms of the adaptive and/or maladaptive nature of the response are discussed.

The accurate assessment and physiotherapeutic treatment of rotator cuff myofascial Pain Syndrome: A case report

Management  of  patients  with  rotator  cuff  myofascial  pain syndrome varies  and  successful  intervention  is  dependent  on accurate assessment. The aim of this case report is to show the importance of accurate assessment  and  clinical  reasoning  in  the  physiotherapeutic management  of a  patient  suffering  from  ante-cubital  and  anterior shoulder  pain.  The  patient was  referred  for  physiotherapy  after proving refractory  to  treatment  with  non-steroidal anti-inflammatory medication. The physiotherapist diagnosed a rotator cuff myofascial pain syndrome and treatment proceeded on that basis. Treatment consisted of twitch-obtaining dry needling, myofascial release and exercise therapy.  The result was a change in the harryman rotator cuff functional Assessment Scale score from 22/52 to 43/52 over eight treatments. Strength was regained and subjective pain report on the visual rating scale was improved to 1/10. The case study highlights the importance of accurate assessment and consideration of alternative myofascial sources for pain even in circumstances which initially seem trauma related. Precise diagnosis of the cause - in this case rotator cuff myofascial pain syndrome – will result in effective treatment being administered.

The potential and limitations of DOV 216,303 as a triple reuptake inhibitor for the treatment of major depression: a microdialysis study in olfactory bulbectomized rats

DOV 216,303 belongs to a new class of antidepressants, the triple reuptake inhibitors (TRIs), that blocks serotonin, norepinephrine and dopamine transporters and thereby increases extracellular brain monoamine concentrations. The aim of the present study was to measure extracellular monoamine concentrations both in the prefrontal cortex (PFC) and dorsal hippocampus (DH) after chronic administration of DOV 216,303 in the OBX animal model of depression and to compare the effects with acute drug treatment. OBX animals showed lower dopamine levels in PFC upon acute administration of DOV 216,303 than sham animals for up to five weeks after surgery. No such changes were observed in the DH. Unexpectedly, a DOV 216,303 challenge in chronic DOV 216,303 treated sham animals resulted in a blunted dopamine response in the PFC compared to the same challenge in vehicle treated animals. This blunted response probably reflects pharmacokinetic adaptations and/or pharmacodynamic changes, since brain and plasma concentrations of DOV 216,303 were significantly lower after chronic administration compared to acute administration. Surprisingly, and in contrast what we have reported earlier, chronic DOV 216,303 treatment was unable to normalize the hyperactivity of the OBX animals. Interestingly, by measuring the drug plasma and brain levels, it was demonstrated that at the time of behavioral testing (24 h after last drug treatment) DOV 216,303 was not present anymore in either plasma or brain. This seems to indicate that this putative antidepressant drug has no lasting antidepressant-like behavioral effects in the absence of the drug in the brain.

Cocaine-induced changes in affective state modulate the light-enhanced startle response

In order to evaluate the influence of changes in affective state on light-enhanced startle, the effects of positive affect, induced by acute cocaine administration, and the effect of negative affect, induced by spontaneous cocaine withdrawal-induced anxiety, were studied. Acute cocaine administration decreased LES, whereas withdrawal from chronic cocaine administration exacerbated LES 24h after withdrawal, an effect indicative of increased anxiety. This exacerbated LES was reduced, but not back to normal, 4 days after withdrawal. The finding that both cocaine-induced positive and negative affect can be detected in LES, suggests that this may be a valuable tool in studying affect regulation in rodents.

The association between psychological stress and low back pain among district hospital employees in Gauteng, South Africa

The presence of low back pain (LBP) can be influenced by psychosocial  stress experienced  at  work.  The  aim  of  this  study  was  to  determine the point prevalence for LBP and the psychological stress expe-rienced at work as a factor associated with the presence of LBP amongst staff  employed  at  district  hospital  in  Pretoria,  Gauteng,  South  Africa.  A  self-administered questionnaire was  completed  by  all  participants. Results indicated that the point prevalence for LBP was 47.46%. Sixty five point five seven percent of employees who experienced stress at work all the time, suffered from LBP (p=0.001). Stress experienced at work all the time increased the risk of LBP (OR 3.47 CI 1.46 ; 8.23).  A clinical recommendation resulting from this study is that healthcare providers need to include the provision of education, support and appropriate  referral for patients who perceive themselves to have high levels of stress.