Knots: Attractive Places with High Path Tortuosity in Mouse Open Field Exploration

When introduced into a novel environment, mammals establish in it a preferred place marked by the highest number of visits and highest cumulative time spent in it. Examination of exploratory behavior in reference to this “home base” highlights important features of its organization. It might therefore be fruitful to search for other types of marked places in mouse exploratory behavior and examine their influence on overall behavior.Examination of path curvatures of mice exploring a large empty arena revealed the presence of circumscribed locales marked by the performance of tortuous paths full of twists and turns. We term these places knots, and the behavior performed in them—knot-scribbling. There is typically no more than one knot per session; it has distinct boundaries and it is maintained both within and across sessions. Knots are mostly situated in the place of introduction into the arena, here away from walls. Knots are not characterized by the features of a home base, except for a high speed during inbound and a low speed during outbound paths. The establishment of knots is enhanced by injecting the mouse with saline and placing it in an exposed portion of the arena, suggesting that stress and the arousal associated with it consolidate a long-term contingency between a particular locale and knot-scribbling.In an environment devoid of proximal cues mice mark a locale associated with arousal by twisting and turning in it. This creates a self-generated, often centrally located landmark. The tortuosity of the path traced during the behavior implies almost concurrent multiple views of the environment. Knot-scribbling could therefore function as a way to obtain an overview of the entire environment, allowing re-calibration of the mouse''s locale map and compass directions. The rich vestibular input generated by scribbling could improve the interpretation of the visual scene.     

First record of Cyclopterus lumpus L., 1758 (Osteichthyes: Cyclopteridae) in the Mediterranean Sea

The Atlantic lumpsucker Cyclopterus lumpus (343 mm total length) is recorded for the first time from the Mediterranean Sea. The specimen was collected in the night between 16 and 17 September 2004 off Molunat Bay, Croatia, southern Adriatic Sea. This record may present a case of a vagrant specimen.     

Noncanonical binding of calmodulin to aquaporin-0: implications for channel regulation

Aquaporins (AQPs) are a family of ubiquitous membrane channels that conduct water across cell membranes. AQPs form homotetramers containing four functional and independent water pores. Aquaporin-0 (AQP0) is expressed in the eye lens, where its water permeability is regulated by calmodulin (CaM). Here we use a combination of biochemical methods and NMR spectroscopy to probe the interaction between AQP0 and CaM. We show that CaM binds the AQP0 C-terminal domain in a calcium-dependent manner. We demonstrate that only two CaM molecules bind a single AQP0 tetramer in a noncanonical fashion, suggesting a form of cooperativity between AQP0 monomers. Based on these results, we derive a structural model of the AQP0/CaM complex, which suggests CaM may be inhibitory to channel permeability by capping the vestibules of two monomers within the AQP0 tetramer. Finally, phosphorylation within AQP0's CaM binding domain inhibits the AQP0/CaM interaction, suggesting a temporal regulatory mechanism for complex formation.     

A conformational change in the N terminus of SLC38A9 signals mTORC1 activation

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Lead exposure among mothers and their newborns in Toronto.

Recent studies have suggested that a fetal blood lead level of 0.48 mumol/L (much lower than 1.21 mumol/L, which is the level previously believed to be toxic to the developing brain) may impair brain development permanently. We measured the maternal and umbilical cord blood levels of lead and free erythrocyte protoporphyrin (FEP) among 95 consecutive mother-infant pairs to determine whether neonates in Toronto are in the high-risk group. There was a significant correlation between the maternal and the cord blood lead levels (r = 0.59, p less than 0.0001). Most (99%) of the infants had cord blood lead levels below 0.34 mumol/L; in 11 cases the levels were below the detection limit of 0.01 mumol/L. The cord blood FEP levels were higher than the maternal levels. The US Centers for Disease Control, Atlanta, currently finds acceptable a blood FEP level of 0.62 mumol/L among children up to 10 years of age; however, this is not applicable to newborns since their higher FEP levels apparently reflect immature heme synthesis and increased erythrocyte volume rather than lead poisoning. Our data suggest that living in Toronto does not impose increased teratogenic risk from intrauterine exposure to lead; however, residents in high-risk areas should be followed up.     

Health Perceptions,Self and Body Image,Physical Activity and Nutrition among Undergraduate Students in Israel

Purpose

This study examines health perceptions, self and body image, physical exercise and nutrition among undergraduate students.

Methods

A structured, self-reported questionnaire was administered to more than 1500 students at a large academic institute in Israel. The study population was heterogenic in both gender and fields of academic study.

Results

High correlations between health perceptions, appropriate nutrition, and positive self and body image were found. The relationships between these variables differed between the subpopulation in the sample and the different genders. Engagement in physical exercise contributed to positive body image and positive health perceptions more than engagement in healthy nutrition. Nutrition students reported higher frequencies of positive health perceptions, positive self and body image and higher engagement in physical exercise in comparison to all other students in the sample.

Conclusions

This study suggests, as have many before, that successful health promotion policy should reflect a collectivist rather than an individualist ethos by providing health prerequisites through a public policy of health-promotion, where the academic settings support a healthy lifestyle policy, by increasing availability of a healthy, nutritious and varied menu in the cafeterias, and offering students various activities that enhance healthy eating and exercise.

Implications and contribution

This study examined health perceptions, self-image, physical exercise and nutrition among undergraduate students and found high correlations between these topics. Nutrition students reported higher frequencies of positive health perceptions, and positive self and body image and engaged more in physical exercise when compared with all other students in the sample.     

Evoxymetopon moricheni,a new cutlassfish from the northern Red Sea (Teleostei: Trichiuridae)

Evoxymetopon moricheni n. sp. is described from the northern Gulf of Aqaba, Red Sea, on the basis of a single specimen. It is characterised within the genus by a convex upper head profile; the posterior confluence of the frontal ridges slightly elevated at the nape, resulting in the presence of a slight sagittal crest; eye 5.2 times in head length; the lower hind margin of opercle slightly pointed in its lower half; the pelvic fins reduced to a scale-like structure with two soft rays on the posterior process of the basipterygium, its origin below the eighth dorsal-fin element; the first anal spine single, oval, scale like, and originating a short distance behind the vent (opposite the 34th dorsal-fin soft ray), anterior anal-fin soft rays minute and embedded, barely penetrating the skin and not visible externally, while the posterior fin supporting the rays enlarged and visible externally; approximately 17 anal-fin rays externally visible; approximately 83 dorsal-fin elements, with first spine not elongate, shorter than second; 12 pectoral-fin rays (ii + 6 + iv), with shorter anterior (fourth ray shortest) and longer posterior rays extending above the lateral line; 10 upper and 13 lower gill rakers of the first gill arch; head and body silver white, with a blackish margin anteriorly on snout and head, continuing along the anterior half of the dorsal-fin base. The new finding represents a new record of the genus from the Red Sea.     

Type 2 diabetes is associated with the MTNR1B gene,a genetic bridge between circadian rhythm and glucose metabolism,in a Turkish population

Molecular Biology Reports - Type 2 diabetes (T2D) is a complicated public health problem in Turkey as well as worldwide. Genome-wide approaches have been guiding in very challenging situations,...