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Backgrounds and Objectives: Clinical observations indicate that cutaneous hyperalgesia may arise from pain located in deep structures. The objective of this study was to investigate whether combined sensitization of deep and superficial somatic tissues facilitates skin hyperalgesia.Methods: The interaction between muscle and cutaneous hyperalgesia was investigated in 16 healthy volunteers. Skin sensitization was induced unilaterally on the same randomly selected part of the body by ultraviolet B (UVB) irradiation above the upper trapezius and low back muscles. The next day, muscle hyperalgesia was induced bilaterally in low back muscles by injections of nerve growth factor (NGF). Thus, 1 day after irradiation there was skin sensitization, whereas after 2 days both skin and muscle sensitizations were present. Cutaneous blood flow, pin-prick thresholds, pressure pain thresholds (PPTs), temporal summation to repetitive painful pressure stimulation, and stimulus-response functions of graded pressure stimulations and pain intensity were assessed within the irradiated skin area and in the surrounding area before and 1, 2 and 3 days after irradiation.Results: Comparing baseline with 1 day after irradiation, UVB and UVB+NGF locations demonstrated: (1) Increased superficial blood flow inside the irradiated area (p < 0.01); (2) Reduced pin-prick (p < 0.01) and PPTs (p < 0.05) within the irradiated area and in the surrounding area; (3) Left-shifted pressure stimulus-response function within the irradiated area (p < 0.01); (4) Facilitated temporal summation inside the irradiated area (p < 0.01).Conclusions: Using skin and deep tissue pain sensitization models simultaneously, no significant synergistic effects were found within the 3-day investigation suggesting little integration between the two phenomena in this period. [ABSTRACT FROM AUTHOR]

Background Among the current translational inflammatory pain models, the ultraviolet ( UV) irradiation is of rapidly growing interest. The development of primary thermal and mechanical hyperalgesia has been observed in humans and rodents. The pig as a translational animal model might be advantageous due to its great homology with humans. Methods The skin in the flank of awake pigs was irradiated by a UV- B light source (1 J/cm2) and changes in thermal and mechanical sensitivity 24 and 48 h following irradiation were measured via assessment of nociceptive behaviours. Results Thermal sensitivity increased significantly within the inflamed site 24 h after irradiation as indicated by the reduction of latency to respond to thermal stimulation from baseline to 24 h ( P < 0.05). At 48 h, the response latency had not decreased any further ( P = 0.414). Thermal sensitivity was also higher at the inflamed skin site than at the control site 24 and 48 h following irradiation ( P < 0.05). An overall decrease of 50% of the baseline mechanical threshold was observed 24 and 48 h following UV- B irradiation ( P = 0.092). Following the inflammatory challenge, the mechanical sensitivity was higher at the site of irradiation compared with the control skin at both 24 and 48 h ( P < 0.05). Conclusions Our study shows that behavioural recordings are a valid tool for the assessment of thermal hyperalgesia following UV- B inflammation in porcine skin, but they were not capable of providing a clear indication of the development of mechanical hyperalgesia. [ABSTRACT FROM AUTHOR]

Background Porcine skin exhibits a high degree of homology to human skin, and the pig has recently been used as a cutaneous pain model. However, before the full potential of this novel in vivo cutaneous pain model can be achieved, several methodological aspects related to the management of awake animal studies in a large species require further examination. This manuscript describes the initial development of a porcine model of cutaneous nociception and focuses on interactions between the sensory modality, body size and the anatomical location of the stimulation site. Methods Pigs of different body sizes (30 and 60 kg) were exposed to thermal ( CO2 laser) and mechanical (pressure application measurement device) stimulations to the flank and the hind legs in a balanced order. The median response latency and the type of behavioural response were recorded. Results Small pigs exhibited significantly lower pain thresholds (shorter latency to response) than large pigs to thermal and mechanical stimulations. Stimulations at the two anatomical locations elicited very distinct sets of behavioural responses, with different levels of sensitivity between the flank and the hind legs. Furthermore, small animals exhibited lower levels of individual variability between single stimulations. Conclusions Our data indicate that this experimental approach may be valuable for use in studies that focus on porcine cutaneous nociception. [ABSTRACT FROM AUTHOR]

Describes research which applied standard nomenclature and data collection techniques to block grant-funded nutrition services in Wisconsin in 1985 and 1986. Concludes that use of block grant funding can add flexibility in meeting the need for nutrition services, but that it is restricted in scope. Implications; References.

Background The mediator mechanisms of the cutaneous wheal and flare response, which underlies allergic skin and urticarial conditions, are controversial. The wheal results primarily from a direct effect of histamine on the local vascular bed, but to what extent does histamine diffuse within the wheal? The flare is neurogenic in origin, being disseminated within the dermis by axon reflexes, but do the neuropeptides released from the nerve endings cause the vasodilatation directly or do they induce the further release of histamine which then transduces the flare? Objective We have addressed these questions by inserting 216 µm diameter microdialysis fibres into the dennis within the different areas of the wheal and flare to monitor changes in histamine levels provoked by intradermal injections of histamine, allergen, codeine and substance P. Twenty-one subjects participated in the investigations. Results The histamine concentration in unprovoked skin was 10.5 ± 0.6 nM. As the dialysis efficacy was ∼50%, this equates to tissue concentrations of 20 nM. All provicants released large amounts of histamine at the injection site, maximum histamine levels being 337-1293 nM. Diffusion of histamine within the wheal was poor, levels at 2.3 mm and 3.7 mm from the site of injection being 4 22% and 0.2-3.7% respectively of those I mm from the injection site. No increased histamine levels were detected in the flare with any provicant. Atraumatic delivery to the skin of histamine in infusion concentrations of 3010 000 nM caused concentration-related effects, at least 100 nM being necessary to induce a significant increase in skin blood flow, a threshold of 300-1000 being required to stimulate a visible flare and a measurable erythema, and 3000-10 000 nM being the minimum for induction of a wheal. Thus the skin blood vessels and nerves are responsive to histamine, but at relatively high concentrations. Conclusions These data support the theory that the flare reaction to focal histamine injection or release is a neurogenic reflex not involving histamine release at its effector end. [ABSTRACT FROM AUTHOR]

We report the results of an open, prospective study on the efficacy of systemic ranitidine in the treatment of psoriasis. Twenty patients suffering from moderate to severe psoriasis were included in the study. The median pretreatment PASI score was 15.7 (range 6.0–24.7). The patients were treated with oral ranitidine 300 mg twice a day for 6 months; no other medication was allowed during the study period. Eighteen patients completed the study. The median PASI score was reduced from 15.7 to 14.5, 9.1 and 5.7, after 1, 3 and 6 months of treatment, respectively (P> 0.00001). A significant reduction in PASI score was evident at 3 months of treatment. A mild to moderate deterioration occurred in 15 patients within the first month of treatment, but this was followed by improvement during prolonged treatment in most patients. No other clinical and/or biochemical side-effects were observed. Eight patients continued therapy with ranitidine after the study was completed, and none of these patients relapsed during a follow-up period of 12–18 months. The results of the present study suggest that ranitidine may be a beneficial and safe treatment for psoriasis. In addition, high-dose, long-term ranitidine treatment appears to be free from severe adverse effects. [ABSTRACT FROM AUTHOR]