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Notes: Attention is increasingly being focused on the relationship of dissocial Ion constant (pKa) of chemicals and skin irritation presumably caused by pH effects at epidermal levels. Human skin Studies of irritation have utilized both subjective visual-palpation scores and reflectance spectroscopy (RS) or laser Doppler velocimetry (LDV) respectively. Several studies document that erythema determined subjectively and objectively correlates with the degree of skin irritancy, but others report lack of correlation between LDV and irritancy scored subjectively. In this study, pharmacologicol and chemical in vivo, skin irritation was evaluated utilizing an improved reflectance spectrophotometer equipped with computerized data analysis. In 16 white females, a model for skin irritation was induced by a 24-h patch application of 4 basic chemicals, imipramine, norephedrine, nicotine and 8-aminoquinoline, with pKa's ranging from 3.8 to 9.5. Skin pigmentation (melanin) and the relative amounts of oxygenized (arterial) and deoxygenized (venous) hemoglobin present in the erythematous skin were calculated. A clear increase in the hemoglobin content was observed in chemical and vehicle exposed sites. Although skin irritation is a complex phenomenon involving chemical and solution properties, percutaneous absorption and the biological drug response, high pKa (p 〉 0.01) was predictive of acute skin irritation in man using computerized analysis of reflectance spectroscopy, A high correlation between visual score and RS was found (r= 0.91).

Notes: Objective: (i) using a new non-invasive technique capable of evaluating quantitatively and qualitatively the haemoglobin content of the skin (ii) to evaluate delipidization induced by organic solvents. Patients: 11 Caucasians treated for 1 min in a randomized manner on the volar forearm with a mixture of chloroform/methanol (2: 1) (CM) and ether/acetone (1:1) (EA) to delipidize the skin. Method erythema was evaluated by computerized remittance spectroscopy immediately after delipidization and hourly for 2 h. Results: only CM application induced subjectively observed and objectively quantified erythema. Erythema was related to a significant increase in oxygenized haemoglobin content due to dilatation of arterioles in the subpapillary plexus (P〈0.01). The increased blood flow induced a significant (P〈0.01) reduction in de-oxygenized haemoglobin in venous vessels immediately after CM application. Conclusion: short contact with certain potent solvent mixtures causes erythema, possibly due to massive lipid extraction and damage of the skin barrier. Using computerized remittance spectroscopy the visible erythema was composed of an increase in oxygenized haemoglobin and a relative decrease in deoxygenized haemoglobin.

Notes: Background: The severity of symptoms in asthma and other hypersensitivity-related disorders has been associated with changes in mood but little is known about the mechanisms possibly mediating such a relationship. The purpose of this study was to examine the influence of mood on skin reactivity to histamine by comparing the effects of hypnotically induced emotions on flare and wheal reactions to cutaneous histamine prick tests. Methods: Fifteen highly hypnotically susceptible volunteers had their cutaneous reactivity to histamine measured before hypnosis at 1, 2, 3, 4, 5, 10, and 15 min after the histamine prick. These measurements were repeated under three hypnotically induced emotions of sadness, anger, and happiness presented in a counterbalanced order. Skin reactions were measured as change in histamine flare and wheal area in mm2 per minute. Results: The increase in flare reaction in the time interval from 1 to 3 min during happiness and anger was significantly smaller than flare reactions during sadness (P〈0.05). No effect of emotion was found for wheal reactions. Hypnotic susceptibility scores were associated with increased flare reactions at baseline (r=0.56; P〈0.05) and during the condition of happiness (r=0.56; P〈0.05). Conclusions: Our results agree with previous studies showing mood to be a predictor of cutaneous immediate-type hypersensitivity and histamine skin reactions. The results are also in concordance with earlier findings of an association between hypnotic susceptibility and increased reactivity to an allergen.

Notes: The present study demonstrates a previously unnoticed source of bacterial contamination of locally manufactured compressed air for medical use. Air samples were drawn into a specially constructed device, and bacterial contents were identified from growth on agar plates. Various factors contributing to bacterial contamination of compressed air during production are mentioned and preventive measures are discussed.

Notes: In a number of studies it has been shown that psychological factors in general and specifically emotional factors can be correlated to changes in immunological function and defence mechanisms. Although the mediating pathways between the central nervous system and the immune system still remain unclear, it is known that some of the‘classical stress hormones’such as cortisol and catecholamines have modulatory effects on different immunological parameters. In this investigation we wished to study the effect of brief hypnotically induced emotional States on monocyte chemotaxis and endocrinological parameters. Eleven highly hypnotically susceptible volunteers were, while in a deep trance, given suggestions to re-experience earlier life experiences involving intense anger and depression in random order. Before concluding hypnosis subjects were given suggestions to re-experience a feeling of happiness and well-being. Monocyte chemotactic activity in sera and serum levels of cortisol, as well as venous plasma levels of the catecholamines epinephrine, norepinephrine. DOPA and DOPAC. were measured before hypnosis, after each emotional stale and immediately after hypnosis. The results showed a significant difference (P〈0.02) in chemotactic activity between the angry and the depressed emotional states, the depressed state exhibiting a decreased chemotactic index compared with the angry slate. Chemolactic index after the happy relaxed emotional state also showed a significant (P〈0.01) increase compared with both chemotactic index before hypnosis and chemotactic activity after the angry and depressed state. Though there were significant differences between emotions and between emotions and the before-hypnosis-concision, no clear-cut significant differences between the emotional slates of anger and depression could be detected for serum cortisol levels and catecholamine plasma levels. Significant positive correlations (P〈0.01) for differences in chemotactic activity and differences in plasma DOPA levels between emotional states was found. When investigated in vitro, DOPA did not in itself exhibit monocyte chemotactic properties. No other significant correlations between differences in chemotactic activity and other endocrinological parameters could be detected. Soluble interleukin-2 receptors in serum were also measured. No significant differences were found.

Notes: Cutaneous reactivity to challenge with dinitrochlorobenzene (DNCB) and diphenylcyclopropenone (DCP) was studied in 16 volunteers following hypnotic suggestions to increase and decrease response during sensitization. The immunoreactivity to DNCB and DCP was modulated by direct suggestions and guided imagery under hypnosis. The volunteers were highly susceptible subjects selected by means of the Harvard Group Scale of Hypnotic Susceptibility. Form A. Measurement of skin reactions to the challenge I month after sensitization was performed double blindly. Results showed a significant (P〈0.01) difference in visually scored reactions to DCP and DNCB between the group instructed to increase reaction to DCP and decrease reaction to DNCB and the group given the opposite instructions. A non-significant difference (P= 0.055) in skin thickness measured by ultrasound was found between the two groups. The study supports previous reports of experimental modulation of immunoreactivity and indicates that the specific immunnnological processes involved in the development of allergic reactions may be susceptible to psychological factors.

Notes: Cutaneous reactivity against histamine skin prick test (Type I) and purified tuberculin protein derivative (Mantoux reaction, Type IV) was studied in eight volunteers under hypnosis. Types I and IV immunoreactivity were modulated by direct suggestion (Type I) and guided imagery (Type IV). The volunteers were highly susceptible subjects, selected by means of the Harvard Group Scale of Hypnotic Susceptibility, Form A. When the volunteers underwent hypnotic suggestion to decrease the cutaneous reaction to histamine prick test, a significant (P 〈 0.02) reduction of the flare reaction (area of erythema) was observed compared with control histamine skin prick tests. The wheal reaction did not respond to hypnotic suggestion. Neither wheal nor flare reaction could be increased in size by hypnotic suggestion compared with control histamine skin prick tests. A hypnotic suggestion of increasing the Type IV reaction on one arm and decreasing the reaction on the other revealed a significant difference in both erythema size (P 〈 0.02) and palpable induration (P 〈 0.01). In two cases the reactions were monitored by laser doppler blood flowmetry and skin thickness measurement by ultrasound. The difference between the suggested increased and decreased reaction was 19% for the laser doppler bloodflow (in favor of the augmented side), and 44% for the dermal infiltrate thickness. This study objectively supports the numerous uncontrolled case reports of modulation of immunoreactivity in allergic diseases involving both Type I and Type IV skin reactions following hypnotic suggestions.

Notes: Delayed-type hypersensitivity (DTH) reactions to the experimental allergen diphenylcyclopropenone (DCP) were measured in four groups, which either trained (+) or did not train in relaxation (−) during the sensitization and/or the challenge phase. All groups consisted of high and low hypnotic susceptible subjects. While there were no differences in erythema, the mean induration of the group which trained in relaxation in both the sensitization and the challenge phase (+/+) was significantly greater than that of the group which trained in relaxation in the challenge phase only (−/+). Significant correlations were found between induration and hypnotic susceptibility scores, and between induration and degree of perceived relaxation during challenge. High hypnotic susceptible subjects experienced a higher degree of perceived relaxation and exhibited greater indurative and erythematous DTH reactions to DCP than low hypnotic susceptible subjects in all four experimental conditions. Though the mediating mechanisms remain unclear, our results suggest that relaxation may affect the DTH reaction, and support previous findings of higher psychophysiologic reactivity of high hypnotic susceptible subjects.

Notes: summary This paper describes the modulation of human deliberately unilateral mastication by trigeminal and extra-trigeminal standardized painful stimuli. Series with 15 s of gum-chewing before induction of pain, during pain and after pain were quantitatively assessed by jaw-closing muscle electromyography (EMG) and kinematics of the lower jaw. Four different painful stimuli were used: cold stimulation of the frontal region, cold stimulation of the dominant hand, capsaicin stimulation of the hard palate, and pressure painm stimulation of the temporomandibular joint (TMJ). Intensity and quality of perceived pain were rated on visual analogue scales (VAS) and McGill's Pain Questionnaires (MPQ). Analysis of the data showed that frontal cold stimulation was the least painful test and was associated with the fewest changes in masticatory function. Cold stimulation of the hand and palatal capsaicin stimulation caused significant increases in peak amplitudes of EMG bursts from all jaw-closing muscles and faster jaw movements whereas TMJ pressure pain produced significantly lower peak EMG amplitudes. The present results suggest that nociceptive input from different tissues and even extra-trigeminal regions may modulate trigeminal motor function in selective ways. Thus, clinical observations of changes in masticatory function may not always be due to pain in the orofacial region and therefore do not necessitate orofacial treatment.

Notes: We measured sister chromatid exchanges (SCEs) in lymphocytes of eight MF patients before, and 2 h, and 24 h after treatment with topical nitrogen mustard. The mean number of SCEs/cell (± SEM) were 8.15 (±0.62), 8.34 (+ 0.55) and 8.26 (±0.56), respectively. The 2 h and 24 h results do not differ significantly from pretreatment levels. Our results show that concentrations of nitrogen mustard used to control MF do not induce SCEs in peripheral blood lymphocytes.