Transcription-coupled and global genome repair differentially influence UV-B-induced acute skin effects and syste

Exposure to UV-B radiation impairs immune responses in mammals by inhibiting especially Th1-mediated contact hypersensitivity and delayed-type hypersensitivity. Immunomodulation is not restricted to the exposed skin, but is also observed at distant sites, indicating the existence of mediating factors such as products from exposed skin cells or photoactivated factors present in the superficial layers. DNA damage appears to play a key role, because enhanced nucleotide excision repair (NER) strongly counteracts immunosuppression. To determine the effects of the type and genomic location of UV-induced DNA damage on immunosuppression and acute skin reactions (edema and erythema) four congenic mouse strains carrying different defects in NER were compared: CSB and XPC mice lacking transcription-coupled or global genome NER, respectively, as well as XPA and TTD/XPD mice carrying complete or partial defects in both NER subpathways, respectively. The major conclusions are that 1) transcription-coupled DNA repair is the dominant determinant in protection against acute skin effects; 2) systemic immunomodulation is only affected when both NER subpathways are compromised; and 3) sunburn is not related to UV-B-induced immunosuppression

EXPERIMENTS TO TEST « PARAMAGNON THEORIES » : ELECTRICAL RESISTIVITY, LOW TEMPERATURE SPECIFIC HEAT AND MAGNETIZATION MEASUREMENTS ON Ni3Al AND Ni3Ga REVIEWED

On passe en revue les expériences qui appuient les théories du paramagnon. La résistivité électrique à basse température présente des effets de paramagnon prononcés tandis que les mesures de chaleur spécifique ne sont pas en accord avec la théorie. On s'attend à ce que les effets sur l'aimantation à basse température soient trop petits pour être observables dans les systèmes Ni3Al et Ni3Ga.A review of some experiments which can support paramagnon theories is given. The electrical resistivity at low temperatures shows pronounced paramagnon effects, whereas the specific heat measurements are not unambiguously supporting the theory. The effects in low temperature magnetization measurements are expected to be too small to be observable in the Ni3Al and Ni3Ga systems

UV exposure alters respiratory allergic responses in mice

We have tested the hypothesis that exposure to ultraviolet light would inhibit T helper-1 (Th1) responses and stimulate T helper-2 (Th2) responses, and that thus in a mouse model of allergic (i.e. extrinsic) asthma (using ovalbumin [OVA] as the allergen) increased symptoms would be observed, while in a model of Th1-dependent occupational asthma (in which picryl chloride is the allergen) decreased symptoms would be observed. Whereas reduced interferon (IFN)-γ, production, decreased inflammatory responses in the airways, and reduced airway reactivity to nonspecific stimuli were observed in UV-preexposed picryl chloride sensitized and challenged mice, the results in the OVA model were less clear. Increased interleukin (IL)-10 production as a result of UV exposure was observed, together with unchanged IL-4 and IFN-γ. In addition, decreased OVA-specific immunoglobin, IgG1 and IgE, titers were noted, as well as decreased nonspecific airway hyperreactivity. Eosinophilic inflammatory responses were not influenced. The results indicate that UV exposure can have systemic effects that influence ongoing immune responses in the respiratory tract. The effects are not only restricted to immune responses that are predominantly Th1 dependent (i.e. pulmonary delayed-type hypersensitivity and IFN-γ production in response to picryl chloride) but also to immune response that are predominantly Th2 dependent, i.e. decreased specific IgE titers

UV exposure alters respiratory allergic responses in mice

We have tested the hypothesis that exposure to ultraviolet light would inhibit T helper-1 (Th1) responses and stimulate T helper-2 (Th2) responses, and that thus in a mouse model of allergic (i.e. extrinsic) asthma (using ovalbumin [OVA] as the allergen) increased symptoms would be observed, while in a model of Th1-dependent occupational asthma (in which picryl chloride is the allergen) decreased symptoms would be observed. Whereas reduced interferon (IFN)-γ, production, decreased inflammatory responses in the airways, and reduced airway reactivity to nonspecific stimuli were observed in UV-preexposed picryl chloride sensitized and challenged mice, the results in the OVA model were less clear. Increased interleukin (IL)-10 production as a result of UV exposure was observed, together with unchanged IL-4 and IFN-γ. In addition, decreased OVA-specific immunoglobin, IgG1 and IgE, titers were noted, as well as decreased nonspecific airway hyperreactivity. Eosinophilic inflammatory responses were not influenced. The results indicate that UV exposure can have systemic effects that influence ongoing immune responses in the respiratory tract. The effects are not only restricted to immune responses that are predominantly Th1 dependent (i.e. pulmonary delayed-type hypersensitivity and IFN-γ production in response to picryl chloride) but also to immune response that are predominantly Th2 dependent, i.e. decreased specific IgE titers

Disgust affects TNF-alpha, IL-6 and noradrenalin levels in patients with obsessive-compulsive disorder

Neurobiological research of obsessive compulsive disorder (OCD) has rarely taken in account the context dependent evocation of obsessive compulsive symptoms. To bypass this obstacle, this study investigated neurobiological parameters during a standardized disgust provocation paradigm in patients with OCD and healthy controls. Ten OCD patients and 10 healthy controls were exposed to 9 disgust related items using a standardized provocation paradigm. Catecholamines and cortisol in plasma and lipopolysaccharide (LPS) stimulated levels of TNF-alpha and IL-6 by peripheral leucocytes were assessed along with severity of obsessive-compulsive symptoms, disgust, and anxiety levels using Visual Analogue Scales prior, during and after a provocation paradigm. Noradrenalin levels increased, while LPS stimulated TNF-alpha and IL-6 by peripheral leucocytes decreased during exposure to disgust related objects in OCD patients but not in healthy controls. Cortisol levels were not affected by exposure neither in patients nor in controls, but overall cortisol levels of OCD patients were increased compared to controls. In conclusion, our data suggests that symptom provocation in OCD patients with contamination fear is accompanied by alterations in the immune and neuroendocrine systems but does not affect cortisol levels. (C) 2009 Elsevier Ltd. All rights reserve

The Association of Olfactory Function with BMI, Appetite, and Prospective Weight Change in Dutch Community-Dwelling Older Adults

Objectives: The olfactory decline that often accompanies aging is thought to contribute to undernutrition in older adults. It is believed to negatively affect eating pleasure, appetite, food intake and subsequently nutritional status. We have evaluated the associations of olfactory function with BMI, appetite and prospective weight change in a cohort of Dutch community-dwelling older adults. Design: Cross-sectional cohort study. Participants: Dutch community-dwelling older adults from the ongoing Longitudinal Aging Study Amsterdam (LASA). Measurements and setting: In 2012–2013, the 40-item University of Pennsylvania Smell Identification Test (UPSIT) was administered to 824 LASA participants to evaluate their olfactory function. Body weight, height, appetite, comorbidity, cognitive status and socio-demographic factors were also assessed. Follow-up weight was measured after three years. Results: 673 participants (aged 55–65 years) were included in the regression analyses. Median UPSIT-score was 33. When adjusted for potential confounders, lower UPSIT-score (indicative of poorer olfactory function) was not associated with poor appetite (OR = 1.062, p = 0.137) or prospective weight change (B = −0.027, p = 0.548). It was, however, associated with lower BMI in smokers (B = 0.178, p = 0.032), but not in non-smokers (B = −0.015, p = 0.732). Conclusion: Lower olfactory function scores were associated with lower BMI in community-dwelling older adults who smoke, but not with appetite or prospective weight change. Therefore, smoking older adults with olfactory impairments may pose as a vulnerable group with respect to developing undernutrition