Study of small air ions concentrations versus asthma attacks in the region of Athens-Greece after the Chernobyl disaster

A consequence of the Chernobyl disaster was the isolated increase of small air ions for a limited time period over Athens-Greece. Taking advantage of this unique condition we studied the relation of log daily mean concentrations of small positive air ions, small negative air ions, NO2 and SO2 with the total daily number of asthma attacks attendances at the region's largest chest diseases hospital for 35 days following the disaster and during a same time period in the preceding four years. No correlation was found between air ionization and asthma attacks, though the study was of a rather short duration and several possible influencing factors such as aeroallergen concentrations were not taken into consideration.     

Non-invasive measurements of skin pigmentation in situ

Objective in situ measurements of skin pigmentation are needed for accurate documentation of pigmentation disorders, in studies of constitutive and induced skin pigmentation, for testing of the efficacy of pro-pigmentation or de-pigmentation agents, etc. Non-invasive instrumental measurements of skin pigmentation have been used for many decades. All are based on the ability of melanin to attenuate light. However, hemoglobin in dermal capillaries also attenuates light and needs to be accounted for when pigmentation is assessed. The methods under consideration include: (a) single point measurements, in which light reflected from a defined skin area is collected and a pigment index is calculated representing the average pigmentation over the examined area, and (b) imaging methods that attempt to generate a concentration distribution map of melanin pigment for the skin area being imaged. In this article, we describe the potentials and the limitations of the different approaches to both single point and imaging methods.     

Drosophila melanogaster larvae detect low doses of UVC radiation as manifested by a writhing response

Exposure of insects and higher orders of animals to UVC radiation has been shown to result in toxicity with a delayed expression. We have observed an immediate writhing response in slowly wandering third instar larvae of Drosophila melanogaster exposed to UVC radiation at doses that were not lethal. UVB and UVA radiation had no effect. Mutants for the visual and sensory systems appeared to respond normally, but CO₂ anesthesia resulted in reversible inhibition, ebony and silver mutants, which affect different pathways in catecholamine metabolism, showed an absent to reduced response. Using UVC lasers, we were able to demonstrate a response in different regions of the larval body. Furthermore, a 193 nm laser that penetrates only 2–5 μm was able to induce a response but unable to kill the larvae. These results suggest a photochemical reaction occurs in the cuticle which produces free radicals that stimulate the nerves and muscle which are present immediately below the epidermis. Possible targets for the UVC radiation are catecholic compounds secreted and processed into the cuticle of third instar larvae just prior to pupariation whose primary function is to crosslink the protein and carbohydrate components. © 1996 Wiley-Liss, Inc.     

Visible Light Induces Melanogenesis in Human Skin through a Photoadaptive Response

Visible light (400–700 nm) lies outside of the spectral range of what photobiologists define as deleterious radiation and as a result few studies have studied the effects of visible light range of wavelengths on skin. This oversight is important considering that during outdoors activities skin is exposed to the full solar spectrum, including visible light, and to multiple exposures at different times and doses. Although the contribution of the UV component of sunlight to skin damage has been established, few studies have examined the effects of non-UV solar radiation on skin physiology in terms of inflammation, and limited information is available regarding the role of visible light on pigmentation. The purpose of this study was to determine the effect of visible light on the pro-pigmentation pathways and melanin formation in skin. Exposure to visible light in ex-vivo and clinical studies demonstrated an induction of pigmentation in skin by visible light. Results showed that a single exposure to visible light induced very little pigmentation whereas multiple exposures with visible light resulted in darker and sustained pigmentation. These findings have potential implications on the management of photo-aggravated pigmentary disorders, the proper use of sunscreens, and the treatment of depigmented lesions.     

Natural Language Processing in aid of FlyBase curators

Background  

Despite increasing interest in applying Natural Language Processing (NLP) to biomedical text, whether this technology can facilitate tasks such as database curation remains unclear.     

Non‐Invasive Measurements of Skin Pigmentation In Situ

Objective in situ measurements of skin pigmentation are needed for accurate documentation of pigmentation disorders, in studies of constitutive and induced skin pigmentation, for testing of the efficacy of pro‐pigmentation or de‐pigmentation agents, etc. Non‐invasive instrumental measurements of skin pigmentation have been used for many decades. All are based on the ability of melanin to attenuate light. However, hemoglobin in dermal capillaries also attenuates light and needs to be accounted for when pigmentation is assessed. The methods under consideration include: (a) single point measurements, in which light reflected from a defined skin area is collected and a pigment index is calculated representing the average pigmentation over the examined area, and (b) imaging methods that attempt to generate a concentration distribution map of melanin pigment for the skin area being imaged. In this article, we describe the potentials and the limitations of the different approaches to both single point and imaging methods.     

Melanin quantification by in vitro and in vivo analysis of near‐infrared fluorescence

Objective measurements of melanin can provide important information for differentiating melanoma from benign pigmented lesions and in assessing pigmentary diseases. Herein, we evaluate near‐infrared (NIR) fluorescence as a possible tool to quantify melanin. Various concentrations of in vitro Sepia melanin in tissue phantoms were measured with NIR fluorescence and diffuse reflectance spectroscopy. Similar optic measurements were conducted in vivo on 161 normal human skin sites. Diffuse reflectance spectroscopy was used to quantify the melanin content via Stamatas–Kollias algorithm. At physiologic concentrations, increasing in vitro melanin concentrations demonstrated higher fluorescence that was linearly correlated (R² = 0.99, p < .001). At higher concentrations, the fluorescence signal plateaued. A linear relationship was also observed with melanin content in human skin (R² = 0.59, p < .001). Comparing the fluorescence and reflectance signals with in vitro and in vivo samples, the estimated melanin concentration in human skin ranged between 0 and 1.25 mg/ml, consistent with previous quantitative studies involving invasive methods.     

Validity of architectural properties of the hamstring muscles: Correlation of ultrasound findings with cadaveric dissection

The purpose of this study was to compare the architectural parameters of the long head of biceps femoris (BFlh) and semitendinosus (ST) muscles by comparing measurements from ultrasound (US) with those obtained from direct dissection. The BFlh and ST architectures were examined bilaterally in 6 legs from 3 male cadavers. The fascicle length, pennation angle, muscle thickness and muscle and tendon length were obtained from direct measurement and US scans along each muscle. Intraclass correlation coefficients between the two methods ranged from 0.905 to 0.913 for the BFlh variables and from 0.774 to 0.974 for the ST parameters. Compared with the direct measurements, the US method showed a mean typical error of 0.09–0.14 cm for muscle thickness, 1.01–1.31° for the pennation angle, 0.92–1.71 cm for fascicle length and muscle–tendon length measurements. The US method is a valid alternative tool for assessing basic architectural parameters of ST and BFlh components of the hamstring muscles.