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1.
Pilot Feasibility Stud ; 7(1): 67, 2021 Mar 12.
Article in English | MEDLINE | ID: mdl-33712086

ABSTRACT

BACKGROUND: Endometriosis (where endometrial-like tissue is found outside the uterus) affects ~ 176 million women worldwide and can lead to debilitating pelvic pain. There is an unmet need for new medical treatment options for endometriosis. Pelvic peritoneal mesothelial cells of women with endometriosis exhibit detrimental metabolic reprogramming that creates an environment favouring the formation and survival of endometriosis lesions. We have generated powerful preclinical proof-of-concept data to show that it is possible to correct this metabolic phenotype using dichloroacetate (DCA), a non-hormonal compound previously used to treat rare metabolic disorders in children. We plan a single-arm, open-label, single site exploratory clinical trial to inform the design of a future randomised controlled trial (RCT) to determine the efficacy of DCA for the treatment of endometriosis-associated pain. METHODS: We will recruit 30 women with endometriosis-associated pain over a 6-month period. All participants will receive approximately 6.25 mg/kg oral DCA capsules twice daily for 6 weeks, with a dose increase to approximately 12.5 mg/kg twice daily for a further 6 weeks if their pain has not been adequately controlled on this dose regime and side-effects are acceptable. If pain is adequately controlled with minimal side-effects, the lower dose will be continued for a further 6 weeks. The primary objective is to determine whether it is possible to achieve acceptable recruitment and retention rates within the defined exclusion and inclusion criteria. Secondary objectives are to determine the acceptability of the trial to participants, including the proposed methods of recruitment, treatment, follow-up frequency and number of questionnaires. The recruitment rate will be determined by the proportion of patients recruited from the pool of eligible women. The retention rate will be determined by the proportion of participants who attended the final trial visit. DISCUSSION: This is a feasibility study to explore effectiveness and acceptability of the proposed field methodology (recruitment, retention, study processes and compliance with treatment). The results will be used to inform the design of a future RCT. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04046081 Registered 6 August 2019.

2.
S Afr J Sports Med ; 33(1): v33i1a12220, 2021.
Article in English | MEDLINE | ID: mdl-38390585

ABSTRACT

Background: Schoolboy rugby is a popular sport which forms the bedrock of rugby development in many African countries, including Zimbabwe. With burgeoning talent identification programmes, the development of multi-dimensional, logically-validated, and reliable test batteries is essential to inform the objective selection of potentially talented young rugby athletes. Objectives: This study sought evidence on the absolute and relative test-retest reliability of the component test items in the newly-assembled SCRuM test battery. Methods: Utilising a pragmatic test-retest experimental design, a sample of 41 Under-19 schoolboy players playing competitive rugby in the elite Super Eight Schools Rugby League in Harare, Zimbabwe, participated in the study. Results: Physiological and game-specific skills tests which showed good to excellent relative reliability and acceptable absolute reliability, included: 20 m and 40 m speed, L-run, Vertical Jump (VJ), 60 s Push-Up, 2 kg Medicine Ball Chest Throw test (2 kg MBCT), Wall Sit Leg Strength test (WSLS), Repeated High Intensity Exercise test (RHIE), One Repetition Maximum Back Squat (1-RM BS) and Bench Press tests (1-RM BP), Yo-Yo Intermittent Recovery Level 1 test (Yo-Yo IRT L1), Tackling Proficiency test, Passing Ability Skill test and Running and Catching Ability skill test. Conclusion: All these tests are reliable and warrant inclusion in the SCRuM test battery for possible profiling of U19 schoolboy rugby players during the 'in-season' phase provided there is adequate participant familiarisation and test standardisation. The test-retest ICCs and measurement errors are generalisable to other young athletes in this population, making the tests useful for the evaluation of training and developmental effects of the measured constructs.

3.
BMC Res Notes ; 12(1): 536, 2019 Aug 22.
Article in English | MEDLINE | ID: mdl-31439000

ABSTRACT

OBJECTIVE: Although schoolboy rugby is growing in popularity and played at different competitive levels in Zimbabwe, the influence of playing standard on qualities or skills of older male adolescent rugby players is unknown. Utilising a cross-sectional design, this study determined anthropometric, physiological characteristics and rugby-specific game skills defining elite under 19 (U19) schoolboy rugby players. Following development and subsequent assessment of test-retest reliability of School Clinical Rugby Measure (SCRuM) test battery, this study compared performance outcomes of elite rugby players (n = 41), sub-elite rugby players (n = 46) and non-rugby athletes (n = 26) to identify qualities or skills discriminating (i) elite from sub-elite and non-rugby players, and concomitantly (ii) sub-elite from non-rugby players. RESULTS: 40 m speed test (p < 0.001, ES = 1.78) and 2 kg Medicine Ball Chest Throw test (p < 0.001, ES = 1.69) significantly discriminated elite U19 from sub-elite and non-rugby players. These tests further differentiated sub-elite from non-rugby athletes. Additionally, 1RM back squat (p = 0.009, ES = 0.57), 1RM bench press (p = 0.005, ES = 0.61), repeated high-intensity exercise test (p < 0.001, ES = 0.88) and passing ability test (p < 0.001, ES = 0.99) discriminated elite from sub-elite counterparts. These findings highlight important attributes linked to elite U19 schoolboy rugby in Zimbabwe. However, no significant differences were observed for sum of seven skinfold (p = 0.28), tackling (p = 0.08) and catching ability (p = 0.05).


Subject(s)
Athletes , Athletic Performance/physiology , Exercise Test/methods , Football/physiology , Motor Skills/physiology , Muscle Strength/physiology , Physical Fitness/physiology , Adolescent , Anthropometry/methods , Athletic Performance/classification , Athletic Performance/standards , Cross-Sectional Studies , Humans , Male , Schools , Zimbabwe
4.
Hum Mov Sci ; 44: 81-90, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26319360

ABSTRACT

Children with Developmental Coordination Disorder (DCD) have difficulty imagining movements such that they conform to the customary temporal constraints of real performance. We examined whether this ability is influenced by the choice of task used to elicit motor imagery (MI). Performance of typically developing (TD) (n=30) and children with DCD (n=30) was compared on two tasks: the Visually Guided Pointing Task (VGPT) and the Computerized Virtual Radial Fitts Task (C-VRFT). Since the VGPT places higher demands on executive functions like working memory but requires less spatial planning, we reasoned that the C-VRFT would provide a purer measure of motor imagery (or simulation). Based on our earlier work, we predicted that imagery deficits in DCD would more likely manifest on the C-VRFT. Results showed high correlations between tasks in terms of executed and imagined movement time suggest that both tasks measure MI ability. However, group differences were more pronounced in the imagined condition of the radial Fitts' task. Taken together, the more spatially complex C-VRFT appears to be a more sensitive measure of motor imagery, better discriminating between DCD and TD. Implications for theory and practice are discussed.


Subject(s)
Aptitude , Executive Function , Imagination , Motor Skills Disorders/diagnosis , Motor Skills Disorders/psychology , Motor Skills , Orientation , Psychomotor Performance , Biomechanical Phenomena , Child , Female , Humans , Kinesthesis , Male , User-Computer Interface
5.
Neuroscience ; 286: 13-26, 2015 Feb 12.
Article in English | MEDLINE | ID: mdl-25457130

ABSTRACT

The aim of this study was to examine how feedback, or its absence, affects children with Developmental Coordination Disorder (DCD) during a visuo-manual tracking task. This cross-sectional study included 40 children with DCD and 40 typically developing (TD) children between 6 and 10 years old. Participants were required to track a target moving along a circular path presented on a monitor by moving an electronic pen on a digitizing tablet. The task was performed under two visibility conditions (target visible throughout the trajectory and target intermittently occluded) and at two different target velocities (30° and 60° per second). Variables reflecting tracking success and tracking behavior within the target were compared between groups. Results showed that children with DCD were less proficient in tracking a moving target than TD children. Their performance deteriorated even more when the target was occluded and when the target speed increased. The mean tracking speed of the DCD group exceeded the speed at which the target rotated which was attributed to accelerations and decelerations made during tracking. This suggests that children with DCD have significant difficulties in visuo-manual tracking especially when visual feedback is reduced. It appears that their impaired ability to predict together with impairments in fine-tuning arm movements may be responsible for poor performance in the intermittently occluded visuo-manual tracking task.


Subject(s)
Motor Skills Disorders/psychology , Psychomotor Performance , Child , Cross-Sectional Studies , Feedback, Psychological , Female , Humans , Male , Motor Activity
6.
Res Dev Disabil ; 34(9): 2449-61, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23747936

ABSTRACT

Neuromotor Task Training (NTT) and Nintendo Wii Fit Training (Wii training) are both task-based interventions used to improve performance in children with motor coordination problems. The aim of this study was to compare the efficacy of these two interventions on the motor performance, isometric strength and cardiorespiratory fitness (aerobic and anaerobic capacity) of children with Developmental Coordination Disorder (DCD) attending mainstream schools in a low-income setting. A pragmatic, quasi-experimental study design was utilized. Children between the ages of 6-10 years, who scored at or below the 16th percentile on the Movement Assessment Battery for Children-2 (MABC-2) and whose teacher reported a functional motor problem, were allocated to either NTT (n=37) or Wii training (n=19) groups depending on school of attendance. The MABC-2, a hand-held dynamometer, the Functional Strength Measure, the Muscle Power Sprint Test and the 20m Shuttle Run Test were used to assess performance at baseline and after the intervention. The main findings show that the mean motor performance scores of both groups improved over the study period. However, significant differences in improvement were detected between groups, with the NTT group showing greater improvement in motor performance, functional strength and cardiorespiratory fitness. No improvements in isometric strength were seen in either group. The Wii training group showed significant improvement in anaerobic performance. This study provides evidence to support the use of both the Wii Training and NTT for children with DCD. However, in comparison to Wii training, the NTT approach yields superior results across measures of motor proficiency, cardiorespiratory fitness and functional strength. The decision to use either approach may be influenced by resources and time constraints.


Subject(s)
Exercise Therapy/instrumentation , Motor Skills Disorders/physiopathology , Motor Skills Disorders/rehabilitation , Motor Skills/physiology , Muscle Strength/physiology , Video Games , Child , Disability Evaluation , Exercise Therapy/methods , Female , Humans , Isometric Contraction/physiology , Male , Physical Fitness/physiology , Physical Therapy Modalities , Treatment Outcome
7.
Mol Neurobiol ; 23(2-3): 173-85, 2001.
Article in English | MEDLINE | ID: mdl-11817218

ABSTRACT

We isolated the rat synaptotagmin IV (Syt IV) cDNA in a screen for sequences that are specifically induced in neuronal cells. The Syts are a large family of genes thought to mediate synaptic function. Syt IV is brain-specific, induced in hippocampus by depolarization, and predominantly vesicular. To assess the function role of Syt IV in vivo, we generated Syt IV(-/-) mutant mice. Syt IV (-/-) mice are viable and appear normal, indicating this gene is not essential for survival or gross development. However, Syt IV (-/-) mutants, when compared to wild-type littermates, have deficits in fine motor coordination and hippocampus-dependent memory, suggesting Syt IV has a role in normal brain function. The human Syt IV ortholog maps to a region of chromosome 18 previously associated with the human psychiatric disorders, schizophrenia and bipolar disease. These results suggest that Syt IV is required in certain types of neurons for optimal functionality, that perturbations in the levels of Syt IV can result in memory loss in mice, and that Syt IV alterations may lead to psychiatric disease in humans.


Subject(s)
Calcium-Binding Proteins , Membrane Glycoproteins/chemistry , Membrane Glycoproteins/genetics , Mental Disorders/etiology , Mental Disorders/metabolism , Nerve Tissue Proteins/chemistry , Nerve Tissue Proteins/genetics , Amino Acid Sequence , Animals , Humans , Membrane Glycoproteins/metabolism , Mental Disorders/genetics , Molecular Sequence Data , Nerve Tissue Proteins/metabolism , Synaptotagmins
8.
J Biol Chem ; 275(47): 36920-6, 2000 Nov 24.
Article in English | MEDLINE | ID: mdl-10938284

ABSTRACT

Rat synaptotagmin IV (SYT IV) is a depolarization-inducible synaptic vesicle protein. SYT IV homozygous mutant mice are viable and have deficits in fine motor coordination and some forms of memory. In this study, we report the identification of a human SYT IV orthologue. The predicted amino acid sequence of the human SYT IV clone is nearly 90% identical to the rat and mouse SYT IV proteins. In addition, human SYT IV has a characteristic serine for aspartate substitution within the first C2 domain that is conserved among Drosophila, Caenorhabditis elegans, mouse, and rat SYT IV sequences. The human SYT IV gene maps to chromosome band 18q12.3, a region that defines a break point in the synteny with mouse chromosome 18 and has been implicated by associated markers in two human psychiatric disorders. In the human neuroblastoma cell line SK-N-SH, SYT IV is an immediate-early gene inducible by elevated intracellular calcium and by forskolin, an activator of adenylyl cyclase. Expression of human SYT IV mRNA is restricted to brain and is not detectable in non-neuronal tissues. Within brain, human SYT IV mRNA is most highly expressed in hippocampus, with lower levels present in amygdala and thalamus. These results suggest a role for SYT IV in human brain function and in human neurological disease.


Subject(s)
Calcium-Binding Proteins , Chromosomes , Membrane Glycoproteins/genetics , Nerve Tissue Proteins/genetics , Amino Acid Sequence , Animals , Base Sequence , Chromosome Banding , Evolution, Molecular , Humans , In Situ Hybridization , Ligands , Mice , Molecular Sequence Data , Neuroblastoma/metabolism , Rats , Synaptotagmins , Tumor Cells, Cultured
9.
Neurochem Res ; 25(5): 591-602, 2000 May.
Article in English | MEDLINE | ID: mdl-10905620

ABSTRACT

We identify and characterize two classes of immediate-early genes: (i) genes, induced by depolarization in neurons, that play a role in depolarization-induced neuronal plasticity and (ii) genes, induced in neuronal precursors by neurotrophins, that play a causal role in neurotrophin-directed neuronal differentiation. We use rat PC12 pheochromocytoma cells to identify (i) genes preferentially induced by [depolarization or forskolin] versus [Nerve Growth Factor (NGF) or Epidermal Growth Factor (EGF)] and (ii) genes preferentially induced by NGF versus EGF. We describe (i) a collection of genes preferentially induced by depolarization/forskolin in PC12 cells and by kainic acid in vivo, and (ii) a collection of genes preferentially induced by NGF. The synaptotagmin IV gene encodes a synaptic vesicle protein whose level is modulated by depolarization. NGF preferentially induces the urokinase-plasminogen activator receptor in PC12 cells. Antisense oligonucleotide and anti-UPAR antibody experiments demonstrate that NGF-induced UPAR expression is required for NGF-driven PC12 cell differentiation.


Subject(s)
Gene Expression Regulation/physiology , Genes, Immediate-Early/physiology , Nerve Growth Factors/pharmacology , Neuronal Plasticity/physiology , Neurons/physiology , Synapses/physiology , Adrenal Gland Neoplasms , Animals , Cell Differentiation , Colforsin/pharmacology , Epidermal Growth Factor/pharmacology , Gene Expression Regulation/drug effects , Genes, Immediate-Early/drug effects , Kainic Acid/pharmacology , Male , Neuronal Plasticity/genetics , Neurons/cytology , PC12 Cells , Pheochromocytoma , Rats
10.
Proc Natl Acad Sci U S A ; 97(10): 5598-603, 2000 May 09.
Article in English | MEDLINE | ID: mdl-10792055

ABSTRACT

Synaptotagmin (Syt) IV is a synaptic vesicle protein. Syt IV expression is induced in the rat hippocampus after systemic kainic acid treatment. To examine the functional role of this protein in vivo, we derived Syt IV null [Syt IV(-/-)] mutant mice. Studies with the rotorod revealed that the Syt IV mutants have impaired motor coordination, a result consistent with constitutive Syt IV expression in the cerebellum. Because Syt IV is thought to modulate synaptic function, we also have examined Syt IV mutant mice in learning and memory tests. Our studies show that the Syt IV mutation disrupts contextual fear conditioning, a learning task sensitive to hippocampal and amygdala lesions. In contrast, cued fear conditioning is normal in the Syt IV mutants, suggesting that this mutation did not disrupt amygdala function. Conditioned taste aversion, which also depends on the amygdala, is normal in the Syt IV mutants. Consistent with the idea that the Syt IV mutation preferentially affects hippocampal function, Syt IV mutant mice also display impaired social transmission of food preference. These studies demonstrate that Syt IV is critical for brain function and suggest that the Syt IV mutation affects hippocampal-dependent learning and memory, as well as motor coordination.


Subject(s)
Calcium-Binding Proteins , Conditioning, Classical/physiology , Membrane Glycoproteins/genetics , Membrane Glycoproteins/physiology , Memory Disorders/genetics , Memory/physiology , Motor Activity/physiology , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/physiology , Acoustic Stimulation , Animals , Cues , Fear/physiology , Food Preferences , Homozygote , Locomotion , Membrane Glycoproteins/deficiency , Mice , Mice, Knockout , Motor Activity/genetics , Nerve Tissue Proteins/deficiency , Rats , Reflex , Social Behavior , Synaptotagmins , Taste
11.
Mol Biol Cell ; 10(7): 2285-95, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10397765

ABSTRACT

Synaptotagmins (Syts) are a family of vesicle proteins that have been implicated in both regulated neurosecretion and general membrane trafficking. Calcium-dependent interactions mediated through their C2 domains are proposed to contribute to the mechanism by which Syts trigger calcium-dependent neurotransmitter release. Syt IV is a novel member of the Syt family that is induced by cell depolarization and has a rapid rate of synthesis and a short half-life. Moreover, the C2A domain of Syt IV does not bind calcium. We have examined the biochemical and functional properties of the C2 domains of Syt IV. Consistent with its non-calcium binding properties, the C2A domain of Syt IV binds syntaxin isoforms in a calcium-independent manner. In neuroendocrine pheochromocytoma (PC12) cells, Syt IV colocalizes with Syt I in the tips of the neurites. Microinjection of the C2A domain reveals that calcium-independent interactions mediated through this domain of Syt IV inhibit calcium-mediated neurotransmitter release from PC12 cells. Conversely, the C2B domain of Syt IV contains calcium binding properties, which permit homo-oligomerization as well as hetero-oligomerization with Syt I. Our observation that different combinatorial interactions exist between Syt and syntaxin isoforms, coupled with the calcium stimulated hetero-oligomerization of Syt isoforms, suggests that the secretory machinery contains a vast repertoire of biochemical properties for sensing calcium and regulating neurotransmitter release accordingly.


Subject(s)
Calcium-Binding Proteins/metabolism , Calcium/metabolism , Membrane Glycoproteins/metabolism , Nerve Tissue Proteins/metabolism , Animals , Binding Sites , Calcium-Binding Proteins/genetics , Cell Differentiation/drug effects , Membrane Glycoproteins/genetics , Membrane Proteins/metabolism , Microinjections , Mutation , Nerve Growth Factors/pharmacology , Nerve Tissue Proteins/genetics , Neurites/metabolism , PC12 Cells/drug effects , PC12 Cells/metabolism , Qa-SNARE Proteins , Rats , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Synaptotagmins
12.
J Neurochem ; 72(5): 1821-31, 1999 May.
Article in English | MEDLINE | ID: mdl-10217258

ABSTRACT

Synaptotagmin IV (Syt IV) is an immediate early gene induced by depolarization in rat PC12 cells and in rat hippocampus. We prepared an antiserum to Syt IV protein. The 46-kDa Syt IV protein is nearly undetectable by western blotting in unstimulated PC12 cells. After depolarization, Syt IV increases rapidly, peaks at 4 h, and decays to near baseline levels by 12 h. Forskolin stimulation also leads to rapid Syt IV protein accumulation. The rate of Syt IV protein synthesis, determined by labeling with radioactive amino acids and immunoprecipitation, is low in unstimulated PC12 cells, but increases over the first 3 h after forskolin stimulation and remains elevated for several hours. Syt IV protein is relatively labile; metabolically labeled Syt IV has a half-life of approximately 2 h in PC12 cells. Sucrose density gradient fractionation and vesicle immunoisolation experiments suggest that Syt IV protein is present in both synaptic-like microvesicles and secretory granules. Vesicles immunoisolated from forskolin-treated PC12 cells with anti-Syt I antibody contain radioactively labeled Syt IV, demonstrating that Syt I and Syt IV colocalize in common vesicles. These results suggest that Syt IV protein, after its stimulation-induced synthesis, is rapidly transported to secretory vesicles where it may transiently modulate the exocytotic machinery.


Subject(s)
Calcium-Binding Proteins , Genes, Immediate-Early/physiology , Membrane Glycoproteins/metabolism , Nerve Tissue Proteins/metabolism , Neurons/metabolism , Subcellular Fractions/metabolism , Animals , Colforsin/pharmacology , PC12 Cells , Rats , Stimulation, Chemical , Synaptic Vesicles/metabolism , Synaptotagmins , Tissue Distribution
13.
J Cell Biol ; 117(5): 1101-7, 1992 Jun.
Article in English | MEDLINE | ID: mdl-1374415

ABSTRACT

FG human pancreatic carcinoma cells use integrin alpha v beta 5 as their primary vitronectin receptor since they fail to express integrin alpha v beta 3. These cells are unable to form focal contacts, spread, or migrate on vitronectin but readily do so on collagen in a beta 1 integrin-dependent manner. Transfection of FG cells with a cDNA encoding the integrin beta 3 subunit results in the surface expression of a functional integrin alpha v beta 3 heterodimer providing these cells with novel adhesive and biological properties. Specifically, FG cells expressing beta 3 acquire the capacity to attach and spread on vitronectin as well as fibrinogen with beta 3 localization to focal contacts. Moreover, these cells gain the capacity to migrate through a porous membrane in response to either vitronectin or fibrinogen. These results demonstrate that the beta 3 and beta 5 integrin subunits when associated with alpha v, promote distinct cellular responses to a vitronectin extracellular environment.


Subject(s)
Cell Adhesion/physiology , Cell Movement/physiology , Fibronectins/metabolism , Glycoproteins/metabolism , Integrins/metabolism , Fluorescent Antibody Technique , Humans , Integrins/genetics , Transfection/genetics , Tumor Cells, Cultured , Vitronectin
14.
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