Detection of fish antigens aerosolized during fish processing using newly developed immunoassays

BACKGROUND: Aerosolization of fish proteins during seafood processing has been identified as a potential route for allergic sensitization and occupational asthma among workers involved in high-risk activities. The aim of this study was to develop immunological assays for the quantification of aerosolized fish antigens in a fish-processing factory. METHODS: Polyclonal antibodies to the main fish species processed in the factory (anchovy and pilchard) were generated in rabbits and compared by ELISA inhibition assay and immunoblotting. These antisera were utilized to develop ELISA assays for the detection of fish antigens. The ELISA inhibition assays were evaluated by analyzing environmental air samples collected from three areas in a fish-processing factory: pilchard canning, fish meal production and lobster processing. RESULTS: By immunoblotting, the rabbit polyclonal antibodies demonstrated IgG antibody binding patterns comparable with IgE antibodies of fish-sensitized patients, particularly in regard to the major fish allergens parvalbumins. The sensitivity of the fish-specific ELISA assays developed was 0.5 microg/ml. The ELISA inhibition assays were able to differentiate between the two different fish species of interest but did not recognize a crustacean species. Notable differences in exposure levels to canned pilchard and anchovy antigens were demonstrated in the three different working areas of the factory, with assays having a detection limit as low as 105 ng/m(3). CONCLUSION: These ELISA-based assays are sensitive and specific to quantify differential exposure levels to fish antigens produced during fish processing, making it possible to investigate exposure-disease response relationships among workers in this industry.     

Fascin,an actin-bundling protein,modulates colonic epithelial cell invasiveness and differentiation in vitro

In epithelial tissue, cell-matrix and cell-cell adhesive interactions have important roles in the normal organization and stabilization of the cell layer. The malignant conversion of epithelial cells involves alterations in the expression and function of these adhesion systems that enable a switch to a migratory phenotype in tumor invasion and metastasis. Fascin is an actin-crosslinking protein that is found in the core actin bundles of cell-surface spikes and projections that are implicated in cell motility. We demonstrate that fascin is not detectable in normal colonic epithelium, but is dramatically up-regulated in colorectal adenocarcinoma. To test the hypothesis that fascin could participate in tumor invasive behavior, we developed a cell culture model to examine the effect of fascin expression on the adhesive interactions, invasiveness, and differentiation of colonic epithelial cells. We report marked effects on the organization of cell-surface protrusions, actin cytoskeleton, and focal adhesions in the absence of alterations in the protein levels of the major components of these structures. These effects correlate with alterations in cell movements on two-dimensional matrix, and increased invasiveness in three-dimensional matrix. The cells also show increased proliferation and decreased capacity for normal glandular differentiation in collagen gels. We propose that up-regulation of fascin, by promoting the formation of protrusive, actin-based, cell-motility structures, could be a significant component in the acquisition of invasive phenotype in colonic carcinoma.     

An ultrastructural study of sperm of the genus Bufo (Amphibia, Anura, Bufonidae)

The sperm ultrastructure of Bufo schineideri and B. granulosus consists of entwined seminiferous tubules formed by groups of germ cells and Sertoli cells. The spermatozoa of B. schineideri and B. granulosus measure about 66.7 microm and 85.4 microm in length, respectively. The head measures approximately 24.8 microm in B. schineideri and 17.7 microm in B. granulosus and consists of a single vesicle acrosomal, subacrosomal cone and nucleus. The midpiece measures approximately 3.8 microm in B. schineideri and 2.5 microm in B. granulosus and presents a mitochondrial collar around the tail. The tail consists of a typical axoneme, 9 + 2 microtubules, paraxonemal rod, axial sheath and axial fiber. The axial fiber extends through an electrondense structure that supports the undulating membrane. The structure and ultrastructure of the spermatozoa of the species here described are similar to the majority of sperm found in the other bufonids and may be a contribution for future phylogenetic analysis.     

Inhibition of RNA synthesis differentially affects in vitro melatonin release from the pineal organs of ayu (Plecoglossus altivelis) and rainbow trout (Oncorhynchus mykiss)

The purpose of this study was to explore how the muscles which control postural body segments are activated during bilateral isometric ramp pushes exerted with the upper limbs by seated subjects. The paradigm under study presents the advantage that the subject is in a quasi-static posture, and since upper limbs are stretched out, the dynamic phenomena, which might occur, can only originate from the rest of the body, which means from the postural chain. A dynamometer was used to measure the horizontal force, Fx, exerted on the bar, and a custom-designed force-plate was used to measure global reaction forces (Rx) and displacement of the centre of pressure (Xp) along the antero-posterior axis. Electromyograms (EMGs) were picked up by bipolar surface electrodes from 14 muscles crossing the lower limb, pelvis, trunk and upper limb joints. It was shown that transient push efforts require monotonous EMG increase in postural as well as in focal muscles. The EMG sequence starts with the postural muscles and ends with the focal ones. The postural EMG sequence is anticipatory. It is concluded that the EMG sequence is programmed according to the task parameters, and that its role is to counteract in advance the perturbing effect of the effort, in order to allow the effort to be performed efficiently. It is suggested that excitation between the postural muscles is distributed according to their biomechanical role in relation to the supports.     

Functional Health Literacy: Psychometric Properties of the Newest Vital Sign for Portuguese Adolescents (NVS-PTeen)

Self-management of health requires skills to obtain, process, understand, and use health-related information. Assessment of adolescents’ functional health literacy requires valid, reliable, and low-burden tools. The main objective of this study was to adapt and study the psychometric properties of the Newest Vital Sign for the Portuguese adolescents’ population (NVS-PTeen). Classic psychometric indicators of reliability and validity were combined with item response theory (IRT) analyses in a cross-sectional survey, complemented with a 3-month test-retest assessment. The NVS-PTeen was self-administered to students enrolled in grades 8 to 12 (12 to 17 years old) in a school setting. Overall, 386 students (191 girls) from 16 classes of the same school participated in the study (mean age = 14.5; SD = 1.5). Internal reliability of the NVS-PTeen was α = 0.60. The NVS-PTeen total score was positively and significantly correlated with Portuguese (r = 0.28) and mathematics scores (r = 0.31), school years (r = 0.31), and age (r = 0.19). Similar to the original scale (for the U.S.), the NVS-PTeen is composed of two dimensions, reading-related literacy and numeracy. Temporal reliability is adequate, though with a learning effect. IRT analyses revealed differences in difficulty and discriminative capacity among items, all with adequate outfit and infit values. Results showed that the NVS-PTeen is valid and reliable, sensible to inter-individual educational differences, and adequate for regular screening of functional health literacy in adolescents.     

Caregivers’ Perceived Emotional and Feeding Responsiveness toward Preschool Children: Associations and Paths of Influence

Although there is a large body of research connecting emotion to eating behaviors, little is known about the role of caregivers’ responses to children’s emotions in the context of child feeding. The purpose of this study was to analyze the relation between caregivers’ emotional responsiveness and feeding responsiveness. The mothers of 137 children between 2 and 6 years of age reported on their responses to children’s negative emotions using the Coping with Children’s Negative Emotions Scale and on their feeding practices using the Comprehensive Feeding Practices Questionnaire. The results showed that mothers’ supportive emotion responses (e.g., problem-focused, emotion-focused, and expressive encouragement reactions) tend to be positively associated with responsive feeding practices (e.g., encouraging, modelling, and teaching healthy food-related behaviors). Instead, mothers’ unsupportive responses (e.g., distress, punitive and minimization reactions) tend to be positively associated with nonresponsive feeding practices (e.g., food as reward or to regulate emotions, and pressure to eat) and negatively associated with responsive feeding practices. Our results suggest that emotional and feeding responsiveness may be intertwined and that differences in parent’s emotional responsiveness may translate into differences in their feeding styles, setting the stage for parents’ use of positive vs. negative feeding practices.     

Lycium barbarum polysaccharide fraction associated with photobiomodulation protects from epithelium thickness and collagen fragmentation in a model of cutaneous photodamage

Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The...     

Antimicrobial photodynamic therapy against Propionibacterium acnes biofilms using hypericin (Hypericum perforatum) photosensitizer: in vitro study

Lasers in Medical Science - Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial...