Psychophysiological Significance of Skin Potential Activity in Monkeys

Skin potential activity was measured on the palmar surface of waking monkeys. The skin potential reflex showed faster habituation to simple light stimuli than to complex sound stimuli. The frequency of spontaneous skin potential responses was higher in the noisy condition than in the rest condition.     

A Direct Comparison of the Skin Conductance and Skin Resistance Methods

The purpose of the present study was a direct comparison between simultaneous recordings of skin conductance and skin resistance. Sixty male students received a series of 30 white noise stimuli, while measures were taken continuously from four sites on the palmar surfaces of the fingers. Evaluations were made for response amplitudes, recovery, and for an approximate area measure. Magnitude of reactions and reliabilities were compared using ANOVA procedures. Behavioral concordances were estimated as correlations with the subjects' ratings of stimulus intensities. Conductance and resistance measures do not differ in amplitude, in area, or in strength of their reliabilities and behavioral concordances. No differences in any respect are found between sites. Skin conductance yields significantly (p < .01) shorter recovery times than skin resistance, which is discussed in terms of membrane permeability change.     

Sympathetic Skin Nerve Discharges in Relation to Amplitude of Skin Resistance Responses

Sympathetic skin nerve action potentials were recorded in the median nerve of 5 healthy college students. A linear and significant correlation was found between the mean voltage amplitude of the sympathetic bursts and the amplitude of skin resistance responses (SRRs). Thus amplitude of skin resistance responses seems to be an index of sympathetic activity.     

Chemopreventive Effect of Cousinia Shulabadensis Attar & Ghahraman Ethanol Extract

Matrix metalloprotainases (MMPs) play an important role in several pathologic processes such as malignancy in which they facilitate invasion and metastasis and can be targets for anticancer therapies. Here, in this study, we investigated the cytotoxicity effect of Cousinia shulabadensis Attar & Ghahraman extract as well as its impact on MMPs activity using a model of cell line (Fibrosarcoma-Wehi164). To assess anti-invasiveness potentials, a modified zymoanalysis method was used to measure MMP-2 and MMP-9 activities in the conditioned-media. The concentration necessary to produce 50% cell death was >80µg/ml for ethanol extract of Cousinia shulabadensis, while a 23 µg/ml concentration of the diclofenac sodium produced the same effect. The invasion of WEHI 164 cells was considerably inhibited at concentrations > 20 µg/ml by total plant extract. The total extract of the plant did not show high toxicity at all tested concentrations, but demonstrated significant inhibition of MMP activity in dose-response fashion.     

Skin sympathetic nerve activity and effector function during sleep in humans

Multi-unit sympathetic skin nerve activity (SSA) in the peroneal nerve was recorded together with electrical skin resistance, skin blood flow and (in some subjects) finger blood pressure during sleep in 22 sleep-deprived healthy subjects. The average strength of sympathetic activity in different sleep stages was measured during 5-min periods as the area-under-curve of the integrated neurogram. Stage 2 sleep was reached by 15 subjects, stages 3–4 by nine and rapid eye movement (REM) sleep by six subjects. Non-REM sleep was always associated with an increased skin resistance, which was larger in glabrous than in hairy skin (293±48 vs. 175±4% of awake control level, n= 10, P < 0.05). Skin blood flow also increased during sleep, with a mean maximal increase of 397±79% of the awake control level (n= 11, P < 0.05). In spite of these changes of effector function no significant difference in mean SSA was found between the awake control period and periods of non-REM sleep, but during REM sleep SSA increased with 34% (P < 0.05) compared with the immediately preceding stage 2 period. In stage 2 sleep, K-complexes were associated with bursts of SSA followed by transient changes of skin resistance, blood flow and arterial blood pressure. When both skin resistance and blood flow were recorded within the innervation area of the impaled fascicle, single bursts or short periods of increased SSA could be succeeded by increased skin blood flow without concomitant skin resistance change. This indicates the existence of specific sympathetic vasodilator fibres in the skin. Therefore the unchanged strength of multiunit SSA during non-REM sleep in the face of increases of skin resistance and blood flow may be a consequence of an increased sympathetic vasodilator nerve activity combined with decreases of vasoconstrictor and sudomotor traffic.     

Evaluation of Aquaporin-3 Role in Nonmelanoma Skin Cancer: An Immunohistochemical Study

Aquaporin-3 (AQP3), is an aquaglyceroporin, that plays a role in cell proliferation, tumorigenesis, and cell migration. This study aimed at evaluating the possible role of AQP3 in nonmelanoma skin cancer (NMSC) pathogenesis through its immunohistochemical expression in skin biopsies of these diseases. One-hundred and thirty cutaneous specimens were studied. These included 60 cases of NMSC and 40 normal skin and 30 psoriasis samples, from age- and gender-matched subjects, as a control group. AQP3 was expressed in 66.7% of basal cell carcinoma (BCC) cases and in 93.3% of squamous cell carcinoma (SCC) cases. Higher AQP3 expression (p?=?.01), expression percentage (p?=?.01), and H score (p?=?.04) were significantly associated with SCC compared to BCC. Normal skin and psoriasis showed significantly higher AQP3 expression (p?=?.001, p?<?.001, respectively), expression percentage (p?<?.001 for both), and H score values (p?<?.001, p?=?.001, respectively) compared to NMSC. Higher H score values in BCC were significantly associated with female gender (p?=?.02) and with nodular lesions (p?>?.001). Higher H score values in SCC were significantly associated with grade III tumors (p?=?.04) and AQP3 percentage of expression was significantly correlated with grade III tumors (r?=?.48, p?=?.009). In conclusion, AQP3 may play a role in NMSC pathogenesis. This probably occurs through aquaporin-mediated glycerol transport and ATP generation. Its downregulation, observed in the current work, is mostly a result of excessive proliferation. Further studies are needed to investigate the therapeutic effect of its inhibition in NMSC treatment.     

Anti-Ulcerogenic Activity of the Methanol Root Bark Extract of Cochlospermum Planchonii (Hook f)

Cochlospermum planchonii (Hook f) is a common medicinal plant used in Nigeria traditional medicine for treatment of different ailments including ulcers. The anti ulcer activity of the root bark methanol extract of Cochlospermum planchonii was evaluated using different [ethanol, acetylsalicylic acid (aspirin), cold/restraint stress and pyloric ligation/histamine - induced ulcers and acid production] ulcerogenic models in rats at the doses of 250, 500, and 1000 mg/kg body weight using cimetidine (100 mg/kg) as a standard reference drug. The different doses of the extract and the reference drug significantly (p < 0.01) decreased all the ulcer parameters in a dose dependent manner in all the models used. The total number of ulcers were significantly (p < 0.05) decreased. The ulcer index was significantly (p < 0.004) reduced by the extract. Similarly, the percentage ulcer preventive index was also increased from 0% in the negative control up to 93.2% at the dose of 1000 mg/kg, while the percentage ulcer severity was dose dependently reduced by the extract. Furthermore, the extract significantly (p < 0.02) decreased free gastric HCl and total gastric acid. In conclusion, Cochlospermum planchonii methanolic root bark extract showed significant antiulcer activity in this study which may be as a result of its cytoprotective, antioxidant or antisecretory properties.     

Examination of the Short-Term Efficacy of a Parent-Based Intervention to Prevent Skin Cancer

The research evaluated an intervention strategy designed to prevent skin cancer in young adolescents. The intervention used parents as change agents to effectively communicate the risks of skin cancer and encourage their children to avoid high-risk sun-related behaviors while increasing positive sun-safe behaviors. Three hundred and forty parents in two regions of the United States were educated about the dangers of risky sun behaviors and how to convey information about skin cancer prevention to their children. Parents were then encouraged to talk with their children about these issues over a 1-month period prior to the onset of summer. Following this time period, children whose parents received and implemented the intervention materials were compared with a control sample of 129 children. These two groups were matched on age, gender, and school on number of sunburns and sunburn severity, attitudes and beliefs, and sunbathing behavior. Children in the treatment condition differed significantly from controls in the predicted directions on all outcome variables. The findings are discussed in terms of reducing skin cancer risk behaviors of children via parent-based intervention approaches.     

Chemopreventive effect of a novel,selective TACE inhibitor on DMBA- and TPA-induced skin carcinogenesis

Context: Tumor necrosis factor (TNF)-α, a potent proinflammatory cytokine, plays a major role in the pathogenesis of cancer. TNF-α converting enzyme (TACE) mediates processing and release of biologically active TNF-α.

Objective: We aimed to investigate the effect of a novel, selective TACE inhibitor (compound 11p) on skin inflammation and associated tumorigenesis in mice.

Methods: Skin edema was induced in mice by dermal application 12-O-tetradecanoylphorbol-13-acetate (TPA) solution in acetone on to the ear and the effect of post-treatment of compound 11p (topical application) was evaluated. Edema and inflammation was assessed by measuring ear thickness, weight of skin punch and cytokine levels. Skin cancer in mice was initiated by single topical application of 7,12-dimethylbenz[a]anthracene (DMBA) and promoted by repeated TPA application for 20 weeks. The effect of compound 11p on papilloma incidence and multiplicity was evaluated.

Results: Treatment with compound 11p strongly suppressed TPA-induced elevation in skin thickness and weight. A dose-dependent suppression in TPA-mediated TNF-α, IL-6, IFN-γ, IL-17 and PGE2 levels which was associated with a decrease in infiltration of inflammatory cells was also observed with the treatment. Moreover, compound 11p treatment delayed the onset, markedly reduced the papilloma incidence and multiplicity persuaded by DMBA and TPA.

Discussion and conclusion: These findings suggest that selective blockade of TACE suppresses TPA-induced epidermal hyperplasia, inflammatory cell infiltration and cytokine level. Inhibition of inflammatory events related to tumor growth might have led to the anti-tumor effect in mouse skin cancer model induced by DMBA and TPA.     

Skin color and cancer mortality among black men in the Charleston Heart Study

The association between skin color and 30-year cancer mortality in a random sample of black men and a peer-nominated group of high socioeconomic status (SES) black men was evaluated in the Charleston Heart Study, a prospective study, begun in 1960, designed to investigate the epidemiology of coronary heart disease in a biracial cohort. Skin color was used as a continuous variable and as a categorical variable, by tertiles, in a Cox proportional hazards regression model. In the high SES group, there was a statistically significant decreasing relationship between skin color and cancer mortality, with those having the lightest skin having the lowest cancer mortality. In the random sample of black men, the relationship between skin color and cancer mortality was not statistically significant; however, the data indicated a slight protective effect among those with the lightest skin color. Because degree of skin reflectance is a measure of black-white admixture, these results may indicate a genetic mechanism underlying the differences in cancer mortality across skin color groups. Skin color is also recognized as a marker for psychosocial factors. Therefore, poor prognosis among those with darker skin color as a result of failure of early detection, inadequate treatment, and a variety of psychosocial stressors represents an alternative explanation of the study findings.     

Protective Effect of Reamberin on Functional Activity of Mitochondria during Skin Ischemia

Reamberin in a dose of 25 mg/kg (succinate concentration) was injected intravenously for 3 days starting from the 1st hour after skin ischemia modeling. This treatment decreased activities of lactate dehydrogenase, aspartate transaminase, and creatine phosphokinase in skin homogenates by 1.6 times, 19%, and 51.3%, respectively. The index of cytolysis decreased by 18%. Reamberin had an energotropic effect, which manifested in an increase in the total ATP content and concentration of creatine phosphate (by 16 and 10%, respectively). After administration of Reamberin, activity of the succinate-ubiquinone reductase system increased by 17%. Under these conditions succinate dehydrogenase activity exceeded the normal by 21%. Reamberin had no effect on the mitochondrial NADH-ubiquinone reductase system in dermal cells during skin ischemia. Superoxide dismutase activity in the area of necrosis increased to the control level on day 3 of treatment with Reamberin. Activities of catalase and glutathione peroxidase increased by 13 and 19%, respectively. Our results indicate that the course of intravenous treatment with Reamberin for 3 days contributes to an increase in reserve capacities of the antioxidant protection system and produces a protective effect during skin ischemia. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 140, No. 10, pp. 436–439, October, 2005     

Suppression of Immediate and Late Anti-IgE-Induced Skin Reactions by Topically Applied Alcohol/Onion Extract

In a double blind study, alcohol/onion extract (5% ethanol) was injected simultaneously with 20 IU and 200 IU rabbit anti-human-IgE intradermally in 12 adult volunteers (6 atopics, 6 non-atopics). Diameters of wheals and flares were measured 10 min after and compared with control sites challenged with 20 IU and 200 IU anti-IgE in a 5% ethanol solution. The skin sites were then treated epidermally with 45% alcohol/onion extract and 45% ethanol under occlusion. Diameters of late cutaneous reactions were measured hourly. Oedema formation was clinically estimated according to an arbitrary scale and skin thickness measured with a calliper. In the onion-treated skin sites the wheal areas were significantly reduced (20 IU: control: 108 +/- 53 mm2; onion 69 +/- 42 mm2, P less than 0.05; 200 IU anti-IgE: control: 152 +/- 25 mm2, onion: 138 +/- 26 mm2, P less than 0.02). The oedema formation during the late phase skin reaction was markedly depressed (P less than 0.005 at 2 h, P less than 0.01 at 4 and 6 h, P less than 0.02 at 8 h). The extent of late skin reactions was slightly, but not significantly reduced. Obviously, onions contain pharmacologically active substances with anti-inflammatory and/or allergic properties.     

Antinociceptive,Anti-Inflammatory and Antipyretic Activities of the Leaf Methanol Extract of Ruta Graveolens L. (Rutaceae) in Mice and Rats

Background

Ruta graveolens has been used to treat toothache, earache, rheumatism and fever with little scientific evidence corroborating these uses.

Materials and Methods

The leaf methanol extract of Ruta graveolens was evaluated for antinociceptive activity using the acetic acid writhing and hot-plate tests in mice, also anti-inflammatory and antipyretic activities using the carrageenan-induced oedema and E. coli-induced pyrexia tests in rats, respectively.

Results

R. graveolens (100 mg/kg, i.p.), significantly reduced the number of acetic acid-induced writhes by 54 %. R. graveolens (400 mg/kg, i.p.), significantly delayed the reaction time in mice to thermal stimulation 15, 30, 45, and 60 min after treatment. Combined treatment of the lowest and sub-effective doses of the leaf methanol extract (25 mg/kg, i.p.), and indomethacin (10 mg/kg, i.p.) significantly reduced the number of acetic acid-induced writhes in mice. The leaf methanol extract of R. graveolens (50 – 400 mg/kg, i.p.), significantly reduced carrageenan-induced oedema over the 4 h period of testing. Combined treatment of the lowest doses of R. graveolens (25 mg/kg, i.p.) and indomethacin (2 mg/kg, i.p.) produced a significant reduction in carrageenan-induced oedema over the 4 h period of testing. R. graveolens (100 -400 mg/kg, i.p.) significantly reduced E. coli-induced pyrexia over the 5 h period of testing. Given together, the lowest dose of R. graveolens (25 mg/kg, i.p.) and pentoxifylline (10 mg/kg, i.p.) produced a significant reduction in pyrexia induced by E. coli (50 µg/kg, i.m.) over the 5 h period of measurement. The LD₅₀ value obtained for R. graveolens was greater than 4000mg/kg (p.o), suggesting that the plant species may be safe in or nontoxic to mice.

Conclusion

The data obtained indicate that R. graveolens has antinociceptive, anti-inflammatory and antipyretic activities, justifying the use of the plant species by traditional medicine practitioners in the management and treatment of pain, inflammation and fever.     

Evaluation of Antibacterial Activity of Prosopis Juliflora (SW.) DC. Leaves

Background

The ethnobotanical importance of Prosopis juliflora is well-known in the folkloric system of medicine for the treatment of various ailments. Although, the study related to the antibacterial potential of this plant, from Central India is scanty.

Material and methods

The in vitro antibacterial activity of Prosopis juliflora leaves collected from the local area was evaluated against ten bacterial type cultures by agar well diffusion assay. The crude extracts prepared by two methods separately with three different solvents were examined for the preliminary antibacterial activity and phytochemical screening, the results of which were used for the choice of solvent and mass extraction of crude extract. Solvent fractionation of crude extract was done employing two sets of solvents namely Set-PCE and Set-HDB which resulted in total, six organic and two aqueous fractions, which were finally subjected to antibacterial activities.

Results

Varying degrees of growth inhibition was shown by all the fractions against tested microorganisms. The highest antibacterial activity was observed in aqueous fractions as compared to solvent fractions.

Conclusion

Isolation and characterization of the bioactive components can be further done by systematic screening of the most active solvent fraction which could lead to the possible source of new antibacterial agents.     

Physical Activity in First-Degree Relatives of Breast Cancer Patients

This study sought to evaluate physical activity in women at moderate risk for breast cancer, the correlates of engaging in regular physical activity, and whether physical activity relates to psychological well-being. The results revealed that 55% of women were regularly active. Logistic regression models indicated that positive affect was associated with increased and negative affect was associated with decreased overall and leisure activity. Older, married, and employed women were more likely to engage in household/occupational activity, whereas women who perceived their risk for breast cancer as high were less likely. More educated women and those with higher perceived risk were more likely to engage in leisure activity, and married women were less likely. These results suggest a need to increase activity levels in women at moderate risk for breast cancer, provide variables upon which interventions can be tailored to promote activity, and point to psychological benefits of activity in this population.     

Prevalence and Correlates of Sun Protection and Skin Self-Examination Practices Among Cutaneous Malignant Melanoma Survivors

Little is known about the level of engagement and correlates of sun protection and skin self-exam among individuals diagnosed with melanoma. Participants (N = 229) completed measures of skin self-exam and sun protection practice and knowledge and attitudes. Approximately eighty-four percent of patients reported engaging in skin self-examination at least once in the past year. Engagement in sun protection practices was moderate. Self-exam practice was associated with gender, physician recommendation about self-exam, and perceived benefits and barriers of self-exam. Sun protection was associated with gender, age, medical status and health care access, physician recommendation, knowledge, and a number of psychological factors. Behavioral interventions to improve skin surveillance and sun protection may benefit from an emphasis on physician education regarding self-exam and sun protection, education regarding the efficacy of sunscreen and the risks associated with sunbathing, reducing perceived barriers to self-exam and sun protection, and reducing reliance on social influences on sun protection practices.     

Skin microautografting. Changes in area and morphology of the new skin

Research and Production Center for Medical Bioengineering, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR D. S. Sarkisov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 109, No. 5, pp. 470–473, May, 1990.     

Effect of Robertsonian Translocations on the Motor Activity Rhythm in the House Mouse

Here we studied the circadian rhythm of motor activity in two groups of wild house mice from the chromosomal polymorphic zone of Barcelona, which differed in diploid number (2n): standard (2n = 40), with all acrocentric chromosomes, and Robertsonian (2n = 29–32), with several Robertsonian translocations. Motor activity under three lighting conditions, light-dark cycle, constant darkness, and constant light, was recorded for each mouse. The motor activity rhythm was examined by Fourier analysis and the daily power spectra were obtained. On the basis of the mean power spectrum of each animal and under each lighting condition, stepwise discriminant analyses were performed to classify the two chromosomal groups. This method allowed the correct classification of a large number of animals, the rhythms of about 2–2.6 hour periods being the most significant, with higher values in Robertsonian than in standard mice. Our results indicate that the daily motor activity pattern differs between the two chromosomal groups and its analysis may have a valuable interest for behavioral investigations on Robertsonian polymorphic zones of this species.     

Skin Type and Optimistic Bias in Relation to the Sun Protection and Suntanning Behaviors of Young Adults

The study examined the roles of general and personal beliefs and skin type in relation to suntanning and sun protection, by assessing various perceptions of risk of skin cancer both for the self and for the average person. A sample of 355 people aged 16 to 25 years was selected randomly from the telephone directory of a coastal provincial city. Highly structured interviews were conducted over the telephone. The findings were presented in relation to three research questions. First, skin type, classified as burn only, burn then tan, or tan without burning, influenced both general and personal beliefs. Compared to the tan-only group, the burn-only group perceived earlier age at onset, greater number of years of life lost, and greater severity of skin cancer, for both the average person and the self, and greater susceptibility to skin cancer for the average person. Second, differences were found between personally relevant and population-relevant beliefs on susceptibility to skin cancer, time of onset, and years of life lost due to skin cancer but not for perceptions of severity and curability. Finally, skin cancer beliefs were poor correlates of tanning and protecting behaviors. The factor explaining the greatest proportion of variance in both behaviors was skin type.     

Electroconvulsive Shock Induces Neuron Death in the Mouse Hippocampus: Correlation of Neurodegeneration with Convulsive Activity

The relationship between convulsive activity evoked by repeated electric shocks and structural changes in the hippocampus of Balb/C mice was studied. Brains were fixed two and seven days after the completion of electric shocks, and sections were stained by the Nissl method and immunohistochemically for apoptotic nuclei (the TUNEL method). In addition, the activity of caspase-3, the key enzyme of apoptosis, was measured in brain areas immediately after completion of electric shocks. The number of neurons decreased significantly in field CA1 and the dentate fascia, but not in hippocampal field CA3. The numbers of cells in CA1 and CA3 were inversely correlated with the intensity of convulsions. Signs of apoptotic neuron death were not seen, while caspase-3 activity was significantly decreased in the hippocampus after electric shocks. These data support the notion that functional changes affect neurons after electric shock and deepen our understanding of this view, providing direct evidence that there are moderate (up to 10%) but significant levels of neuron death in defined areas of the hippocampus. Inverse correlations of the numbers of cells with the extent of convulsive activity suggest that the main cause of neuron death is convulsions evoked by electric shocks.__________Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 90, No. 3, pp. 272–281, March, 2004.