The Conservative Management of Neck Injuries

Previously a list of treatments which might be avoided in the care of simple neck sprains was published. The present discussion is with regard to treatment which may be used safely.The original discussion was to the effect that treatment should be avoided which aggravates the patient''s pain.Now suggestions are made for treatment which should not produce iatrogenic trauma.This treatment has the advantage of reducing the financial cost to the injured person plus the medical advantage of shortening the period of treatment, reducing cost and disability.     

Effects of three stabilizing agents--proline, betaine, and trehalose--on membrane phospholipids

We have studied the interaction between three compounds which accumulate in organisms under hydration stress--proline, betaine, and trehalose--and the membrane phospholipids dimyristoylphosphatidylcholine (DMPC), palmitoyloleoylphosphatidylcholine (POPC), and dimyristoylphosphatidylethanolamine in bulk solution. Film balance studies reveal that these compounds increase the area/molecule of these lipids. Differential scanning calorimetry has been employed to investigate the effect these agents have on the gel-to-liquid crystalline phase transition of multilamellar and small unilamellar vesicles of DMPC, dipalmitoylphosphatidylcholine, and POPC:phosphatidylserine (90:10 mole ratio) in bulk solution. In the presence of 1 M proline, trehalose, or betaine, the midtransition temperature in small unilamellar vesicles is reduced (up to 7 degrees C in 1 M trehalose), and the transition broadened. In contrast, multilamellar vesicles of similar lipid composition show an increased transition temperature in the presence of the same concentration of these compounds. This result suggests that the inner lamellae in multilamellar vesicles may be dehydrated with only a few outer lamellae exposed to the protective compound. Finally, we have used stereomodels of phosphatidylcholine to investigate the mechanism of action of these agents. Hydrogen bonding of trehalose to the head group region results in an increase in the distance between head groups of 6.9 A. This amount of spreading compares well with data from the monolayer experiments which indicate that maximal spreading of DMPC monolayers by trehalose is 6.5 A. Molecular models of proline and betaine have also been constructed, and these models suggest potential interactions between these compounds and phosphatidylcholines. For the amphipath proline, this interaction may involve intercalation between phospholipid head groups.     

Evidence for a water-soluble intermediate in exchange of cholesterol between membranes

The mechanism of inter-membrane cholesterol exchange has been a matter of some debate. Evidence from kinetic studies indicates that cholesterol must transfer to and from membranes in a water-soluble form. In this study attempts have been made to demonstrate that this occurs using either dialysis membranes or a barrierless multiphase polymer system to physically separate the membranes. In both systems small amounts of cholesterol were seen to transfer from one membrane pool to another using both liposomes and erythrocyte membranes as donors or acceptors. The cholesterol transfer was shown to be independent of the movement of other membrane components. The amount of transfer observed was limited by the physical properties of the systems employed. The barrier to cholesterol transfer in the dialysis membrane system is primarily the pore size of the membrane, while in the multiphase polymer system the transfer was limited by the viscosity of the medium and the distance between the lower and upper phases containing the membranes. Nevertheless, the results provide evidence that cholesterol transfer is by a dissociation of molecules from membranes into the aqueous medium and does not require the formation of a collision complex between the membranes.     

Prophylactic and therapeutic testing of Nicotiana-derived RSV-neutralizing human monoclonal antibodies in the cotton rat model

Severe lower respiratory tract infection in infants and small children is commonly caused by respiratory syncytial virus (RSV). Palivizumab (Synagis^®), a humanized IgG₁ monoclonal antibody (mAb) approved for RSV immunoprophylaxis in at-risk neonates, is highly effective, but pharmacoeconomic analyses suggest its use may not be cost-effective. Previously described potent RSV neutralizers (human Fab R19 and F2–5; human IgG RF-1 and RF-2) were produced in IgG format in a rapid and inexpensive Nicotiana-based manufacturing system for comparison with palivizumab. Both plant-derived (palivizumab-N) and commercial palivizumab, which is produced in a mouse myeloma cell line, showed protection in prophylactic (p < 0.001 for both mAbs) and therapeutic protocols (p < 0.001 and p < 0.05 respectively). The additional plant-derived human mAbs directed against alternative epitopes displayed neutralizing activity, but conferred less protection in vivo than palivizumab-N or palivizumab. Palivizumab remains one of the most efficacious RSV mAbs described to date. Production in plants may reduce manufacturing costs and improve the pharmacoeconomics of RSV immunoprophylaxis and therapy.     

Simulation of chelonian hind-limb reflex movements

A model of the hind limb of the terrapin, devoid of sensory feedback, but which is capable of producing realistic reflex movements is presented. It is shown that very small adjustments of the activation pattern of the muscles (the input of the model) are sufficient to correct the movement for different starting positions or to different targets. Mechanical disturbances of the movement can also be simulated. Comparisons with experimental tests with the same sorts of disturbance were done to try and determine if the real system possesses feedback which tries to adjust to the disturbance. Since the simulations of disturbed movements predict fairly well the experimental movements we are drawn to the conclusion that the movement takes place by means of a pattern generator and no compensation against disturbances is present.     

Effects on childhood infections of promoting safe and hygienic complementary-food handling practices through a community-based programme: A cluster randomised controlled trial in a rural area of The Gambia

BackgroundThe Gambia has high rates of under-5 mortality from diarrhoea and pneumonia, peaking during complementary-feeding age. Community-based interventions may reduce complementary-food contamination and disease rates.Methods and findingsA public health intervention using critical control points and motivational drivers, delivered February–April 2015 in The Gambia, was evaluated in a cluster randomised controlled trial at 6- and 32-month follow-up in September–October 2015 and October–December 2017, respectively. After consent for trial participation and baseline data were collected, 30 villages (clusters) were randomly assigned to intervention or control, stratified by population size and geography. The intervention included a community-wide campaign on days 1, 2, 17, and 25, a reminder visit at 5 months, plus informal community-volunteer home visits. It promoted 5 key complementary-food and 1 key drinking-water safety and hygiene behaviours through performing arts, public meetings, and certifications delivered by a team from local health and village structures to all villagers who attended the activities, to which mothers of 6- to 24-month-old children were specifically invited. Control villages received a 1-day campaign on domestic-garden water use. The background characteristics of mother and clusters (villages) were balanced between the trial arms. Outcomes were measured at 6 and 32 months in a random sample of 21–26 mothers per cluster. There were no intervention or research team visits to villages between 6 and 32 months. The primary outcome was a composite outcome of the number of times key complementary-food behaviours were observed as a proportion of the number of opportunities to perform the behaviours during the observation period at 6 months. Secondary outcomes included the rate of each recommended behaviour; microbiological growth from complementary food and drinking water (6 months only); and reported acute respiratory infections, diarrhoea, and diarrhoea hospitalisation. Analysis was by intention-to-treat analysis adjusted by clustering. (Registration: PACTR201410000859336). We found that 394/571 (69%) of mothers with complementary-feeding children in the intervention villages were actively involved in the campaign. No villages withdrew, and there were no changes in the implementation of the intervention. The intervention improved behaviour adoption significantly. For the primary outcome, the rate was 662/4,351(incidence rate [IR] = 0.15) in control villages versus 2,861/4,378 (IR = 0.65) in intervention villages (adjusted incidence rate ratio [aIRR] = 4.44, 95% CI 3.62–5.44, p < 0.001), and at 32 months the aIRR was 1.17 (95% CI 1.07–1.29, p = 0.001). Secondary health outcomes also improved with the intervention: (1) mother-reported diarrhoea at 6 months, with adjusted relative risk (aRR) = 0.39 (95% CI 0.32–0.48, p < 0.001), and at 32 months, with aRR = 0.68 (95% CI 0.48–0.96, p = 0.027); (2) mother-reported diarrhoea hospitalisation at 6 months, with aRR = 0.35 (95% CI 0.19–0.66, p = 0.001), and at 32 months, with aRR = 0.38 (95% CI 0.18–0.80, p = 0.011); and (3) mother-reported acute respiratory tract infections at 6 months, with aRR = 0.67 (95% CI 0.53–0.86, p = 0.001), though at 32 months improvement was not significant (p = 0.200). No adverse events were reported. The main limitations were that only medium to small rural villages were involved. Obtaining laboratory cultures from food at 32 months was not possible, and no stool microorganisms were investigated.ConclusionsWe found that low-cost and culturally embedded behaviour change interventions were acceptable to communities and led to short- and long-term improvements in complementary-food safety and hygiene practices, and reported diarrhoea and acute respiratory tract infections.Trial registrationThe trial was registered on the 17th October 2014 with the Pan African Clinical Trial Registry in South Africa with number (PACTR201410000859336) and 32-month follow-up as an amendment to the trial.

Semira Manaseki-Holland and co-workers evaluate a behaviour-change intervention aimed at improving food hygiene for infants in West Africa.     

Anatomy of the vascular system of the head and neck of the helmeted guineafowl Numida meleagris

The vascular anatomy of the head and neck of eight adult helmeted guineafowl ( Numida meleagris ) was investigated by latex injections and dissection, resin casting, and lipidol injections and X-ray photography. The vascular anatomy of these regions is similar to that of the domestic fowl Gallus domesticus , the main differences being in the helmet, wattle and cere vascularization, and the presence of a nape-cheek rete in N. meleagris . It is postulated that five vascular arrangements in the head and neck are important in brain temperature regulation. These arrangements are: the nape-cheek rete, the temporal rete, fine arteriovenous networks in the wattles and cere, and the cavernous sinus-intercarotid association. All but the last of these arrangements require pathways of blood flow to the brain other than the most direct route. Such pathways are discussed.