Understanding the influence of 24-hour movement behaviours on the health and development of preschool children from low-income South African settings: the SUNRISE pilot study.

Background: The International Study of Movement Behaviours in the Early Years, SUNRISE, was initiated to assess the extent to which young children meet movement behaviour guidelines (physical activity, sedentary behaviour, screen time, sleep). Objective: The South African SUNRISE pilot study assessed movement behaviours in preschool children from two low-income settings, and associations between these movement behaviours, adiposity, motor skills and executive function (EF). Methods: Preschool child/parent pairs (n = 89) were recruited from preschools in urban Soweto and rural Sweetwaters. Height and weight were measured to assess adiposity. Physical activity was assessed using accelerometers while sedentary behaviour, screen time and sleep were assessed via parent report. Fine and gross motor development were measured using the Ages and Stages Questionnaire-3, and EF was assessed using the Early Years Toolbox. Results: The proportion of children meeting the physical activity guideline was 84%, 66% met the sleep guideline, 48% met the screen time guideline, and 26% met all three guidelines. Rural children were more active, but spent more time on screens compared to urban children. Most children were on track for gross (96%) and fine motor (73%) development, and mean EF scores were in the expected range for all EF measures. EF was negatively associated with screen time, and gross motor skills were positively associated with physical activity. Conclusion: The South African SUNRISE study contributes to the growing literature on 24-hour movement behaviours in SA preschool children, and highlights that these behaviours require attention in this age group.

Use of the ages and stages questionnaire adapted for South Africa and Zambia.

BACKGROUND: There are few readily available, relatively easy to use and culturally adaptable developmental assessment tools for young children in southern Africa. The overarching aim of this study is to test the psychometric properties, contextual appropriateness and cut-off scores across 21 age groups of the Ages and Stages Questionnaire Third Edition (Squires & Bricker, ) among a group of typically developing children in South Africa and Zambia through a combination of both caregiver-report and direct observations, and to compare children's performance across sociodemographic variables. METHODS: The sample consisted of 853 children (50.5% Zambia, with 50.1% girls for Zambia and 50% girls for South Africa) aged 2 months to 60 months. Information on caregiver employment, education and household assets were also obtained. RESULTS: The psychometric properties of the ASQ-3 in southern Africa are consistent with those found in the extant literature. Analysis of item difficulty at each age reveals adequate levels of difficulty for majority of the items, with exception of the problem solving domain where half of the items at 54 and 60 months have poor pass rates. Sociodemographic variables were significantly associated with children's performance: higher caregiver levels of education are associated with higher toddler scores on the personal-social domain and higher preschooler scores on the problem solving domain; children whose caregivers earn a salary have higher fine motor scores during toddlerhood and higher problem solving scores during preschool and children who attend preschools have higher gross motor scores during toddlerhood and higher fine motor scores during the preschool years. CONCLUSIONS: Findings provide evidence to support the psychometric properties and feasibility of using the ASQ-3 in both South Africa and Zambia through a combination of caregiver-report and direct observations.

Utilization and practical aspects of tele-ophthalmology between South Africa and the UK.

A tele-ophthalmology service was established between a regional hospital in South Africa and a specialist eye hospital in the UK. The aim of the service was to provide secondary specialist advice in the diagnosis and treatment of difficult ophthalmology cases in South Africa. Over 12 months, the South African medical officers saw 16,458 ophthalmology patients and would have liked a second opinion in 5.7% of these cases. Case discussions conducted by videoconferencing at 384 kbit/s were carried out in 0.5% of cases. No significant connection problems were experienced during the 12-month study period. On 4% of occasions, the case discussions were conducted at a bandwidth of 256 kbit/s, but this did not affect the quality of the still images. The South African medical officers valued the educational benefits gained from the case discussions with the UK specialists.

Temporary remission of disseminated paecilomycosis in a German shepherd dog treated with ketoconazole.

Disseminated mycosis caused by Paecilomyces varioti in a female German shepherd dog presented with chronic forelimb lameness is described. Radiographs of the swollen carpal joint revealed geographic lysis of the radial epiphysis. Diagnosis was based on cytological demonstration of fungal hyphae and chlamydiospores, as well as fungal culture of fluid obtained by arthrocentesis. Temporary remission was characterised by markedly improved clinical signs and laboratory parameters, following treatment with ketoconazole. The dog was euthanased 9 months after the initial diagnosis, following the diagnosis of multifocal discospondylitis. This appears to be the longest described period of temporary remission obtained with treatment in dogs with paecilomycosis. Clinical, clinicopathological and necropsy findings of this disease in another German shepherd dog are briefly described.

Modular motif, structural folds and affinity profiles of the PEVK segment of human fetal skeletal muscle titin.

The extension of the PEVK segment of the giant elastic protein titin is a key event in the elastic response of striated muscle to passive stretch. PEVK behaves mechanically as an entropic spring and is thought to be a random coil. cDNA sequencing of human fetal skeletal PEVK reveals a modular motif with tandem repeats of modules averaging 28 residues and with superrepeats of seven modules. Conformational studies of bacterially expressed 53-kDa fragment (TP1) by circular dichroism suggest that this soluble protein contains substantial polyproline II (PPII) type left-handed helices. Urea and thermal titrations cause gradual and reversible decrease in PPII content. The absence of sharp melting in urea and thermal titrations suggests that there is no long range cooperativity among the PPII helices. Studies with solid phase and surface plasmon resonance assays indicate that TP1 interacts with actin and some but not all cloned nebulin fragments with high affinity. Interestingly, Ca(2+)/calmodulin and Ca(2+)/S100 abolish nebulin/PEVK interaction. We suggest that in aqueous solution, PEVK is an open and flexible chain of relatively stable structural folds of the polyproline II type. PEVK region of titin may be involved in interfilament association with thin filaments in a calcium/calmodulin-sensitive manner. This adhesion may modulate titin extensibility and elasticity.

Dirofilaria repens in a cat with acute liver failure.

Acute liver failure was diagnosed in a 12-year-old cat. Fine needle aspirate cytology revealed high numbers of unsheathed microfilariae and a hepatocellular reaction with no evidence of bacterial infection. The microfilariae were identified as those of Dirofilaria repens by acid phosphatase staining. The high number of microfilariae seen in both the blood and the liver aspirate samples as well as the favourable response to ivermectin amongst other drugs administered, is suggestive that D. repens was the cause of the liver insult. A positive result obtained with an antigen-capture ELISA (Dirochek) for Dirofilaria immitis antigen was interpreted as false. This is the 1st report of Dirofilaria repens for South Africa.

Malignant fibrous histiocytoma of the deep peri-articular tissue of the stifle in a dog.

A Belgian shepherd dog aged 4 years and 9 months was presented with acute onset of non-weight bearing lameness and stifle effusion of the left hind limb, caused by the deep form of a malignant fibrous histiocytoma originating in the deep musculature and fascia surrounding the stifle joint. The tumour progressed rapidly in the tissues along the femoral diaphysis with marked periosteal new bone formation. Cytology of a stifle joint aspirate revealed numerous large polygonal neoplastic cells with considerable anisocytosis and anisokaryosis. These cells were present in clusters, with cytoplasmic projections between the cells, but occasionally also occurred singly. Several cells contained multiple cytoplasmic vacuoles and occasional giant cells were also encountered. Adequate tumour-free margins were not possible with radical limb amputation and the dog was euthanased. Macroscopically the tumour appeared as an extensive pale tan, firm mass with scattered small haemorrhages and foci of yellow discolouration. Histologically the tumour consisted of dense neoplastic expanses or multiple nodules, composed of spindle-shaped fibroblastic cells, polygonal histiocytic cells or cell clusters and scattered giant cells with 2-3 nuclei. The polygonal neoplastic cells were frequently present around and invading lymphatics and blood vessels, causing neoplastic emboli. This is the 1st report of the clinical behaviour, radiography and cytology of the deep form of malignant fibrous histiocytoma in the dog.

pH-dependent and ligand induced conformational changes of eucaryotic protein synthesis initiation factor eIF-(iso)4F: a circular dichroism study.

The structural features of wheat germ protein synthesis initiation factor eIF-(iso)4F, which has a cap binding protein as one of its two subunits, are unknown. In this study, circular dichroism (CD) spectra and secondary structure prediction were obtained for eIF-(iso)4F and its two subunits, p28 and p86. The alpha-helix content of eIF-(iso)4F changed from 42% at pH 6.3 to 15% at pH 7.6, the optimum pH for cap binding. The beta-sheet content increased from 14% (pH 6.3) to 38% at pH 7.6. The CD spectra of the two subunits, p28 and p86 were also measured and analyzed. The separated subunits both had a higher alpha-helix content at pH 7.6 than the native protein, giving values of 60% and 34% alpha-helix for p28 and p86, respectively. Binding of the dinucleotide cap analog to p28 reduced the alpha-helix content to approximately 8% with an increase in the beta sheet content from 10% to 37%. The conformational changes in eIF-(iso)4F upon binding with mRNA are dependent on cap or oligonucleotide structure. A conformation consisting of approximately the same alpha-helix and beta-sheet content can be induced by ligands even at non-optimal pH values. This large conformational transition suggests eIF-(iso)4F binds nucleic acids by interaction of a beta-sheet motif and that this conformational transition may have a regulatory role.

Human skeletal muscle nebulin sequence encodes a blueprint for thin filament architecture. Sequence motifs and affinity profiles of tandem repeats and terminal SH3.

Analysis of deduced protein sequence and structural motifs of approximately 5500 residues of human fetal skeletal muscle nebulin reveals the design principles of this giant multifunctional protein in the sarcomere. The bulk of the sequence is constructed of approximately 150 tandem copies of approximately 35-residue modules that can be classified into seven types. The majority of these modules form 20 super-repeats, with each super-repeat containing a 7-module set (one of each type in the same order). These super-repeats are further divided into eight segments: with six segments containing adjacent, highly homologous super-repeats, one single repeat segment consisting of 8 nebulin modules of the same type, and a non-repeat segment terminating with a SH3 domain at the C terminus. The interactions of actin, tropomyosin, troponin, and calmodulin with nebulin fragments consisting of either repeating modules or the SH3 domain support its role as a giant actin-binding cofilament of the composite thin filament. Such affinity profiles also suggest that nebulin may bind to tropomyosin and troponin to form a composite calcium-linked regulatory complex on the thin filament. The modular construction, super-repeat structure, and segmental organization of nebulin sequence appear to encode thin filament length, periodicity, insertion, and sarcomere proportion in the resting muscle.

Interaction of wheat germ protein synthesis initiation factor eIF-(iso)4F and its subunits p28 and p86 with m7GTP and mRNA analogues.

The binding of p28, p86, and native wheat germ eIF-(iso)4F with m7GTP and oligonucleotides was measured and compared. The purified subunits (p28, 28 kDa and p86, 86 kDa) of wheat germ protein synthesis initiation factor eIF-(iso)4F have been obtained from Escherichia coli expression of the cloned DNA (van Heerden, A., and Browning, K. S. (1994) J. Biol. Chem. 269, 17454-17457). The binding of the 5'-terminal cap analogue m7GTP to the small subunit (p28) of eIF-(iso)4F as a function of pH, temperature, and ionic strength is described. The mode of binding of p28 to cap analogues is very similar to the intact protein. Assuming that all tryptophan residues contribute to p28 and eIF-(iso)4F fluorescence, iodide quenching shows that all 9 tryptophan residues in p28 are solvent-accessible, while only 6 out of 16 tryptophan residues are solvent-accessible on the intact eIF-(iso)4F. The fluorescence stopped-flow studies of eIF-(iso)4F and p28 with cap show a concentration-independent conformational change. The rate of this conformational change was approximately 10-fold faster for the isolated p28 compared with the native eIF-(iso)4F. From these studies it appears that cap recognition resides in the p28 subunit. However, p86 enhances the interaction with capped oligonucleotides and probably is involved in protein-protein interactions as well. Both subunits are required for helicase activity.

Function of the p86 subunit of eukaryotic initiation factor (iso)4F as a microtubule-associated protein in plant cells.

The isozyme form of eukaryotic initiation factor 4F [eIF-(iso)4F] from wheat germ is composed of a p28 subunit that binds the 7-methylguanine cap of mRNA and a p86 subunit having unknown function. The p86 subunit was found to have limited sequence similarity to a kinesin-like protein encoded by the katA gene of Arabidopsis thaliana. Native wheat germ eIF-(iso)4F and bacterially expressed p86 subunit and p86-p28 complex bound to taxol-stabilized maize microtubules (MTs) in vitro. Binding saturation occurred at 1 mol of p86 per 5-6 mol of polymerized tubulin dimer, demonstrating a substoichiometric interaction of p86 with MTs. No evidence was found for a direct interaction of the p28 subunit with MTs. Unlike kinesin, cosedimentation of eIF-(iso)4F with MTs was neither reduced by MgATP nor enhanced by adenosine 5'-[gamma-imido]triphosphate. Both p86 subunit and p86-p28 complex induced the bundling of MTs in vitro. The p86 subunit was immunolocalized to the cytosol in root maize cells and existed in three forms: fine particles, coarse particles, and linear patches. Many coarse particles and linear patches were colocalized or closely associated with cortical MT bundles in interphase cells. The results indicate that the p86 subunit of eIF-(iso)4F is a MT-associated protein that may simultaneously link the translational machinery to the cytoskeleton and regulate MT disposition in plant cells.

Expression in Escherichia coli of the two subunits of the isozyme form of wheat germ protein synthesis initiation factor 4F. Purification of the subunits and formation of an enzymatically active complex.

The subunits (p28 and p86) of the isoenzyme form of eukaryotic initiation factor 4F (eIF-(iso)4F) from wheat were expressed separately in Escherichia coli. The subunits were purified by affinity chromatography (p28) and ion-exchange chromatography (p86). The purified subunits alone did not support polypeptide synthesis in an eIF-(iso)4F and eIF-4F-deficient translation system from wheat germ. However, when the two subunits were mixed together, activity equal to that of the native form of eIF-(iso)4F was obtained. These results show that subunits expressed separately are able to associate and form an enzymatically active complex.

Attempted treatment of canine ehrlichiosis with imidocarb dipropionate.

Six clinical and 10 experimentally-induced cases of canine ehrlichiosis were treated with imidocarb dipropionate. The treatment did not result in clinical cure and failed to sterilize the infection. The infection was successfully transmitted from treated dogs to splenectomized and non-splenectomized dogs.

Wesselsbron disease, pathological, haematological and clinical studies in natural cases and experimentally infected new-born lambs.

This is a report on the clinical signs of Wesselsbron disease in 37 lambs and the pathology of 4 natural and 12 experimental cases. Generally the symptoms were ill-defined. At autopsy 13 of the 14 lambs revealed a mild to severe icterus and a slight to moderate hepatomegaly with discoloration of the liver. No foci of hepatic necrosis were observed macroscopically and, except for petechial and ecchymotic haemorrhages in the mucosa of the abomasum and generalized lymphadenopathy, no other obvious macroscopic lesions were noted. Perforation of the abomasum occurred in one lamb only. Microscopy on the liver showed mild to extensive necrosis of the parenchyma. Degenerated and necrotic hepatocytes were diffusely scattered throughout the liver, but no definite well-circumscribed foci of necrosis were seen. Mitotic figures and hepatocytes with large nuclei indicated that active regeneration of parenchymal cells had occurred in some of the livers. Other changes, for example, Kupffer cell proliferation, sinusoidal leucostasis, bile duct proliferation and infiltration of mononuclear cells in the portal triads, were frequently encountered. Moderate to severe cholestasis was a feature in 66% of the livers examined, while intranuclear inclusions and intracytoplasmic acidophilic or Councilman-like bodies were frequently observed. A complete haematological study was carried out on 4 experimentally produced cases. The gross and histopathological lesions in the liver are compared with those of Rift Valley fever in the new-born lamb.

[Sheep scab: control and problems in South Africa (author's transl)]. / Skaapbrandsiekte-beheer en enkele probleme.

This is a summary compiled on a regional basis from reports of officials of the Division of Veterinary Services in respect of sheep scab outbreaks occurring between 1967 and 1976. Possible sources of infection responsible for outbreaks occurring between 1940 and 1966 are discussed. Action to be taken where the disease is suspected, and control measures in terms of the Animal Diseases and Parasites Act (13/1956) when the disease has been confirmed, are dealt with. Possible causes for the continuing spread of the disease and dipping problems are discussed. Recommendations for the future control and eradication of sheep scab in the Republic of South Africa are put forward.