The role of the lateral spinal nucleus in nociception

The lateral spinal nucleus (LSN), located in the dorsolateral funiculus, is an area that has been poorly understood, but has been implicated in nociception. To investigate the function of this nucleus, three broad areas were investigated: responses to nociceptive stimuli, neurochemical relations to the NK-1 receptor, and projections from this nucleus to several brain centres, to try to gain a greater understanding of the functions of this nucleus. The following conclusions can be drawn from the studies undertaken here: • A series of double-labelling experiments for confocal microscopy were carried out in the rat (Sprague-Dawley) to investigate the LSN responses to a variety of peripheral cutaneous noxious stimuli. It was found that the LSN responds to both thermal and chemical peripheral cutaneous noxious stimulation. However, unlike as previously thought, only a small number of neurons in the LSN are activated by a peripheral noxious stimulus, with hot water (55°C applied to the hind-paw) activating the most, as revealed by Fos immunoreactivity. Only 15% of LSN neurons showed response to this peripheral noxious stimulus. Interestingly, unlike the superficial dorsal horn (SDH), bilateral activation of LSN neurons after the application of a peripheral noxious stimulus was found in most of the experiments carried out. • Triple and quadruple-labelling experiments for confocal microscopy were carried out in the rat to investigate neurochemical relations at this site. It was found that although the LSN is abundant in staining for substance P, the number of LSN neurons showing immunoreactivity for the target of substance P (the NK-1 receptor) represented only one-third of all neurons at this site. However, substance P and nitric oxide synthase were associated with NK-1 neurons, and specifically nitric oxide synthase terminals were preferentially associated with NK-1 neuronal cell bodies. However, unlike the superficial dorsal horn, nitric oxide synthase terminals were not associated with inhibitory GABAergic neurons. • Using retrograde injection techniques (in the rat) combined with multiple immunolabelling for confocal microscopy, the LSN was shown to project to areas traditionally associated with nociception (caudal ventrolateral medulla and mediodorsal thalamus) but also projected to the hypothalamus and also the lateral globus pallidus. Indeed, the regions found to have the most projections from the LSN were the lateral and medial hypothalamus, with most of those neurons (>80%) possessing the NK-1 receptor. Interestingly, although numbers of retrogradely labelled neurons were low, they represented 30% of all labelled neurons that projected from the LSN to the lateral globus pallidus. In conclusion, the extent of involvement of the LSN in nociception is less than previously thought, but with projections to the hypothalamus, it could be postulated that the LSN functions as an integrative nucleus for autonomic and homeostatic functions, and related motivational and affective responses to autonomic function

The surgical anatomy of the extra-temporal portion of the facial nerve in relation to parotidectomy

The facial nerve passes through the substance of the parotid gland and therefore, surgery on this gland (commonly for parotid tumours) places the nerve at great risk. The facial nerve needs to be preserved as it supplies the muscles of facial expression and therefore damaging it will have severe cosmetic and functional consequences. There has been dispute in the past as to whether to locate the facial nerve during parotid gland surgery from an anterograde approach, where the main trunk is identified early in the procedure (Corcione and Califano, 1990) or, by a retrograde approach, where the peripheral branches are identified first (Yu, 2001). In Glasgow, the facial nerve is identified in parotidectomy by the anterograde approach. This means that the facial nerve is identified after it leaves the skull at the stylomastoid foramen but before it enters the parotid gland. A landmark at this point which can be used to identify the facial nerve is the tympanomastoid suture, although other landmarks have been used in the past (Holt, 1996; Conley, 1978; Heeneman, 1975 and Boswell, 1959). The null hypotheses which are to be tested are that in parotid surgery: The tympanomastoid suture is not a reliable landmark to use to locate the extra-temporal portion of the facial nerve. The tympanomastoid suture is not a safe landmark to use to locate the extra-temporal portion of the facial nerve. o The tympanomastoid suture is not any more reliable in locating the extratemporal portion of the facial nerve compared to other landmarks which have been used in the past. To test this proposition the following work will be undertaken: To test the reliability of using the tympanomastoid suture in locating the facial nerve: 1. The tympanomastoid suture will be identified in the cadaver. 2. The suture will be used to identify the facial nerve. 3. The distance will be measured from the tympanomastoid suture to the main trunk of the facial nerve (ie. its extra temporal portion) and this will be repeated on a series of cadavers. To test the safety of the tympanomastoid suture in locating the facial nerve: 1. The relationship of the suture line to the facial nerve and other surrounding structures will be examined. 2. The facial nerve will be traced distally and surrounding structures to it will be examined. 3. A parotidectomy (which involves identifying the facial nerve early in the operation) will be carried out on the cadaver to see the other structures which may be at risk. To test the reliability of the tympanomastoid suture against other landmarks: 1. Three other surrounding landmarks will be identified: the "tragal pointer", the posterior belly of digastric muscle and the junction of the cartilaginous and bony external auditory canal to examine their relationship to the facial nerve. 2. Distances will be measured from the main trunk of the facial nerve to each of these landmarks and serial measurements will be undertaken. Finally, the identification of the facial nerve at operation will be observed to judge the safety and reliability of identifying the main trunk early in the operation and to see if any other complications arise. It is hoped these types of measurements above may also be useful in the future in terms of computer-guided surgery

A Live Bio-Therapeutic for Mastitis, Containing Lactococcus lactis DPC3147 With Comparable Efficacy to Antibiotic Treatment

peer-reviewedBovine mastitis is an ongoing significant concern in the dairy and agricultural industry resulting in substantial losses in milk production and revenue. Among the predominant etiological agents of bovine mastitis are Staphylococcus aureus, Streptococcus uberis, Streptococcus dysgalactiae, and Escherichia coli. Currently, the treatment of choice for bovine mastitis involves the use of commercial therapeutic antibiotic formulations such as TerrexineTM, containing both kanamycin and cephalexin. Such antibiotics are regularly administered in more than one dose resulting in the withholding of milk for processing for a number of days. Here, we describe the optimization of a formulation of Lactococcus lactis DPC3147, that produces the two-component bacteriocin lacticin 3147, in a liquid paraffin-based emulsion (formulation hereafter designated ‘live bio-therapeutic’) for the first time and compare it to the commercial antibiotic formulation TerrexineTM, with a view to treating cows with clinical/sub-clinical mastitis. Critically, in a field trial described here, this ‘ready-to-use’ emulsion containing live L. lactis DPC3147 cells exhibited comparable efficacy to TerrexineTM when used to treat mastitic cows. Furthermore, we found that the L. lactis cells within this novel emulsion-based formulation remained viable for up to 5 weeks, when stored at 4, 22, or 37◦C. The relative ease and cost-effective nature of producing this ‘live bio-therapeutic’ formulation, in addition to its enhanced shelf life compared to previous aqueous-based formulations, indicate that this product could be a viable alternative therapeutic option for bovine mastitis. Moreover, the singledose administration of this ‘live bio-therapeutic’ formulation is a further advantage, as it can expedite the return of the milk to the milk pool, in comparison to some commercial antibiotics. Overall, in this field trial, we show that the live bio-therapeutic formulation displayed a 47% cure rate compared to a 50% cure rate for a commercial antibiotic control, with respect to curing cows with clinical/sub-clinical mastitis. The study suggests that a larger field trial to further demonstrate efficacy is warranted

Masses, radii, and orbits of small Kepler planets : The transition from gaseous to rocky planets

We report on the masses, sizes, and orbits of the planets orbiting 22 Kepler stars. There are 49 planet candidates around these stars, including 42 detected through transits and 7 revealed by precise Doppler measurements of the host stars. Based on an analysis of the Kepler brightness measurements, along with high-resolution imaging and spectroscopy, Doppler spectroscopy, and (for 11 stars) asteroseismology, we establish low false-positive probabilities (FPPs) for all of the transiting planets (41 of 42 have an FPP under 1%), and we constrain their sizes and masses. Most of the transiting planets are smaller than three times the size of Earth. For 16 planets, the Doppler signal was securely detected, providing a direct measurement of the planet's mass. For the other 26 planets we provide either marginal mass measurements or upper limits to their masses and densities; in many cases we can rule out a rocky composition. We identify six planets with densities above 5 g cm-3, suggesting a mostly rocky interior for them. Indeed, the only planets that are compatible with a purely rocky composition are smaller than 2 R ⊕. Larger planets evidently contain a larger fraction of low-density material (H, He, and H2O).Peer reviewedFinal Accepted Versio

Enabling and Enhancing Science Exploration Across the Solar System: Aerocapture Technology for SmallSat to Flagship Missions

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