Structural Organization of the Presynaptic Density at Identified Synapses in the Locust Central Nervous System

In a synaptic active zone, vesicles aggregate around a densely staining structure called the presynaptic density. We focus on its three-dimensional architecture and a major molecular component in the locust. We used electron tomography to study the presynaptic density in synapses made in the brain by identified second-order neuron of the ocelli. Here, vesicles close to the active zone are organized in two rows on either side of the presynaptic density, a level of organization not previously reported in insect central synapses. The row of vesicles that is closest to the density's base includes vesicles docked with the presynaptic membrane and thus presumably ready for release, whereas the outer row of vesicles does not include any that are docked. We show that a locust ortholog of the Drosophila protein Bruchpilot is localized to the presynaptic density, both in the ocellar pathway and compound eye visual neurons. An antibody recognizing the C-terminus of the Bruchpilot ortholog selectively labels filamentous extensions of the presynaptic density that reach out toward vesicles. Previous studies on Bruchpilot have focused on its role in neuromuscular junctions in Drosophila, and our study shows it is also a major functional component of presynaptic densities in the central nervous system of an evolutionarily distant insect. Our study thus reveals Bruchpilot executes similar functions in synapses that can sustain transmission of small graded potentials as well as those relaying large, spike-evoked signals. J. Comp. Neurol. 520:384–400, 2012. © 2011 Wiley Periodicals, Inc

Social connections and risk of incident mild cognitive impairment, dementia, and mortality in 13 longitudinal cohort studies of ageing

INTRODUCTION: Previous meta-analyses have linked social connections and mild cognitive impairment, dementia, and mortality. However, these used aggregate data from North America and Europe and examined a limited number of social connection markers. METHODS: We used individual participant data (N = 39271, Mage  = 70.67 (40-102), 58.86% female, Meducation  = 8.43 years, Mfollow-up  = 3.22 years) from 13 longitudinal ageing studies. A two-stage meta-analysis of Cox regression models examined the association between social connection markers with our primary outcomes. RESULTS: We found associations between good social connections structure and quality and lower risk of incident mild cognitive impairment (MCI); between social structure and function and lower risk of incident dementia and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality. DISCUSSION: Different aspects of social connections - structure, function, and quality - are associated with benefits for healthy aging internationally. HIGHLIGHTS: Social connection structure (being married/in a relationship, weekly community group engagement, weekly family/friend interactions) and quality (never lonely) were associated with lower risk of incident MCI. Social connection structure (monthly/weekly friend/family interactions) and function (having a confidante) were associated with lower risk of incident dementia. Social connection structure (living with others, yearly/monthly/weekly community group engagement) and function (having a confidante) were associated with lower risk of mortality. Evidence from 13 longitudinal cohort studies of ageing indicates that social connections are important targets for reducing risk of incident MCI, incident dementia, and mortality. Only in Asian cohorts, being married/in a relationship was associated with reduced risk of dementia, and having a confidante was associated with reduced risk of dementia and mortality

Investigation of Multiple Susceptibility Loci for Inflammatory Bowel Disease in an Italian Cohort of Patients

BACKGROUND: Recent GWAs and meta-analyses have outlined about 100 susceptibility genes/loci for inflammatory bowel diseases (IBD). In this study we aimed to investigate the influence of SNPs tagging the genes/loci PTGER4, TNFSF15, NKX2-3, ZNF365, IFNG, PTPN2, PSMG1, and HLA in a large pediatric- and adult-onset IBD Italian cohort. METHODS: Eight SNPs were assessed in 1,070 Crohn's disease (CD), 1,213 ulcerative colitis (UC), 557 of whom being diagnosed at the age of ≤16 years, and 789 healthy controls. Correlations with sub-phenotypes and major variants of NOD2 gene were investigated. RESULTS: The SNPs tagging the TNFSF15, NKX2-3, ZNF365, and PTPN2 genes were associated with CD (P values ranging from 0.037 to 7×10(-6)). The SNPs tagging the PTGER4, NKX2-3, ZNF365, IFNG, PSMG1, and HLA area were associated with UC (P values 0.047 to 4×10(-5)). In the pediatric cohort the associations of TNFSF15, NKX2-3 with CD, and PTGER4, NKX2-3, ZNF365, IFNG, PSMG1 with UC, were confirmed. Association with TNFSF15 and pediatric UC was also reported. A correlation with NKX2-3 and need for surgery (P  =  0.038), and with HLA and steroid-responsiveness (P  =  0.024) in UC patients was observed. Moreover, significant association in our CD cohort with TNFSF15 SNP and colonic involvement (P  =  0.021), and with ZNF365 and ileal location (P  =  0.024) was demonstrated. CONCLUSIONS: We confirmed in a large Italian cohort the associations with CD and UC of newly identified genes, both in adult and pediatric cohort of patients, with some influence on sub-phenotypes

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Neuroleon microstenus

First instar larva of <i>Neuroleon microstenus</i> <p>Body colouration: head black with shiny black jaws, ventral side of the thorax and abdomen whitish straw, dorsal side light brown.</p> <p>Size: body length (including mandibles) 4–4.5 mm, body width (widest part) 1.5 mm, head length (without mandibles) 0.9–1 mm, head width 0.9–1.2 mm, length of the mandibles 1–1.1 mm.</p> <p> Head. Anterior margin of the head is weakly sinuate (Figs. 1, 2). The head surface is covered with numerous dolichasters and scarce plumose hairs (Figs. 3, 5). All dolichasters occurring in <i>N. microstenus</i> are grooved longitudinally. On the frontal margin of the head, between the mandibles, there are six longer dolichasters arranged in two groups and close to them there is a pair of campaniform sensilla (Fig. 3). Antenna (Fig. 6) about 2.5 times longer than basal width of mandible. The number of antennal segments varies from 15 to 17. On the distal part of the last flagellomere sensilla basiconica are found (Fig. 8). Shiny black mandibles are equipped with three teeth (Fig. 4). Distance between tooth 1 and 3 is longer than greatest mandibular width. Tooth 3 is longer than 2 which is longer than 1. Mandible typically with 2 black longitudinally grooved bristles (sensilla chaetica) between mandibular base and tooth 1, 1 bristle between tooth 1 and 2, and 1 bristle between tooth 2 and 3. No bristles between the third tooth and pointed end of mandible. Bristles on outer margin of mandible extend from its basal region to the level of tooth 3. Mandibular bristles significantly shorter than tooth 3. Mandibles and maxillae bear a great number of contact chemoreceptor organs—sensilla coeloconica (Figs. 9–11). The sensilla are set on the floor of relatively shallow depressions in the cuticle and are scattered in the whole length of the jaws including mandibular teeth. The labial palps are four-segmented. On the tip of the labial palps sensilla basiconica occur (Fig. 12). Eyes consisting of seven stemmata are borne on prominent eye tubercles (Fig. 6). Six stemmata of each eye are grouped on the dorsal anterior side of the tubercle, the seventh, rudimentary stemma is positioned on its ventral side (Fig. 7). On eye tubercle, several dolichasters are present.</p> <p>Thorax. Prothorax has fine granular sculpture with longitudinally grooved dolichasters and plumose hairs scattered on its dorsal side (Fig. 13). Between pro- and mesothorax a pair of ungrooved sensilla trichodea occurs. The spiracles of mesothorax are equipped with marginal dent-like structures and are situated laterally on prominent tubercles (Fig. 14). Paired segmental extensions—scoli—equipped with tufts of long, longitudinally grooved bristles (sensilla chaetica), laterally fringe the meso- and metathorax and abdominal segments (Figs. 15–17). The bristles are classified as dolichasters. Wrinkled cuticular surface of thorax and abdomen is rich in bristles and plumose hairs (Fig. 18). Legs are covered with longitudinally grooved bristles (Figs. 19–21). The tip of the tarsus of all legs has two claws. On the tibia of fore leg and on the distal part of the tarsus of hind leg campaniform sensilla are found (Fig. 22). Between the claws two short sensilla trichodea occur (Fig. 23).</p> <p>Abdomen. Sternite 8 bears a pair of small submedian teeth (Fig. 24). Sternite 9 is equipped with stout and pointed fossorial or digging bristles (Fig. 25). On the distal part of the sternite there are two bulges, each of them bearing four digging bristles. On each bulge, the most lateral digging bristle is the longest one and the median is the shortest. All digging bristles are longitudinally grooved. In the proximal part of sternite 9 there is a pair of campaniform sensilla (Fig. 24).</p> <p>Behaviour: In laboratory conditions, larvae were fed on aphids. When larvae are put on sand surface, they move only forwards, whilst in sandy substrate they move backwards.</p> Second and third instar larvae <p>Morphology of second instar is very similar to third instar, but differ in body size.</p> <p>Body colouration: head brown to reddish brown with black or dark brown pigmentation on dorsal side of the head forming “V” mark (Fig. 27, 28); jaws shiny black; ventral side of the thorax and abdomen light brown, dorsal side brown. Size of second instar larvae: body length (including mandibles) 8–10 mm, body width (widest part) 2.5–3 mm, head length (without mandibles) 1.5–1.6 mm, head width 1.4–1.5 mm, length of the mandibles 1.5–1.7 mm. Size of third instar larvae: body length (including mandibles) 10–13 mm, body width (widest part) 3–3.5 mm, head length (without mandibles) 2–2.2 mm, head width 1.8–2 mm, length of the mandibles 2–2.1 mm. Anterior margin of the head and head surface are covered with numerous bristles (sensilla chaetica); many of them have broken tip or are missing in the whole length. All bristles are grooved longitudinally. Shiny black mandibles are equipped with three teeth. Distance between tooth 1 and 3 is twotimes longer than greatest mandibular width. Tooth 3 is longer than 2 which is longer than 1. Mandible is typically equipped with 3–5 short bristles (sensilla chaetica) between mandibular base and tooth 1, 1 bristle between tooth 1 and 2, and 1 bristle between tooth 2 and 3. No bristles are found between the third tooth and pointed end of mandible. The intact bristles occur only in freshly hatched larvae; in older animals most of them are broken and often only a base of the bristle is seen. Bristles on outer margin of mandible are scarce and extend from its basal region to level of tooth 3. Inner jaw bristles are shorter than tooth 1, outer jaw bristles are shorter than tooth 3. Thoracic and abdominal morphology is like in first instar larvae. Sternite 9 is equipped with stout and pointed bristles. On the distal part of sternite 9 there are two bulges, each with four fossorial or digging bristles which are longitudinally grooved (Fig. 26). These digging bristles are longitudinally grooved less clearly than other bristles of the same larva.</p> <p>Behaviour of second and third instar larvae: On sand surface larvae move backwards or forwards. They pursue prey by digging slowly backwards in sand and then whipping the head backwards to grasp prey when it is beneath the larvae. Larvae never ran forwards after prey.</p> Remarks on development <p>In the laboratory rearing, second instar larvae moulted into third instar larvae at the end of June, rarely in July or August. Third instar larvae form ball-like cocoons made of silk and covered with sand grains glued to silk. The diameter of cocoon is 7–9 mm. Pupation lasts 28–30 days. Adults emerged in July and August, rarely in June. The pupa only partly emerged from the cocoon before the adult appeared. Shortly after completion of the adult form, a single pellet of larval excrement (meconium) was deposited. This is elongate, measuring 3.5–4 mm in length and 1 mm in diameter, hard and shining.</p> Discussion <p> Although a number of species of myrmeleontid larvae are mentioned in the literature, only a small proportion is adequately described (reviews: Gepp 1984; Stange & Miller 1990). More papers describing larval morphology and biology deal with pit-building antlion species than non-pit-builders (Gepp 1984). Larvae of <i>N. microstenus</i> have prominent eye tubercles and sparse short bristles on the jaws. Prominent eye tubercles and sparse mandibular bristles are both characteristic for non-pit-builders, like <i>Distoleon</i> (Satar <i>et al.</i> 2006) and other <i>Neuroleon</i> species (Steffan 1975). On the abdomen apex of <i>N. microstenus</i> the two groups of digging bristles are arranged in the same way as in <i>Neuroleon ochreatus</i> (Navás, 1904) (Steffan 1975). Four digging bristles on a bulge are also found in <i>Distoleon</i> (Satar <i>et al.</i> 2006) but their length differs from bristle length in <i>Neuroleon</i> where they are not of equal size. Black pigmentation on the dorsal side of the head forming “V” mark in <i>N. microstenus</i> is similar to the pigmentation pattern in a closely related species, <i>Neuroleon nemausiensis</i> (Borkhausen, 1791) (Steffan 1975). Three types of sensory receptors—campaniform sensilla, sensilla coeloconica and sensilla basiconica—are recognized for the first time in antlion larvae. Campaniform sensilla are recorded on the head, legs and abdomen. It is proposed that two campaniform sensilla on the 9th abdominal sternite play a role in digging into sandy substrate because these mechanoreceptors are known to detect stretch forces in cuticle (McIver 1985; Chapman 1998; Römer 2003). Sensilla coeloconica are present on the mandibles and maxillae of <i>Neuroelon microstenus</i>, and sensilla basiconica were found on the tips of the antennae and labial palps. These receptors play role in detection of chemical substances important in feeding and sensing animal’s environment (Zacharuk 1985; Galizia 2008; Glendinning 2008). Koch (1983) recorded chemoreceptor sensilla on the mandibles of <i>Euroleon</i> and Satar <i>et al.</i> (2006) mentioned antennal sensilla as “three finger shaped lobes” in <i>Distoleon</i>. Chemoreceptors of <i>Neuroleon</i> are present on maxillae and both surfaces of mandible, even on mandibular teeth. These receptors play a role during catching behaviour when prey is grasped and fixed with mandibles and tip of mandibles and teeth penetrate a prey. It is suggested that antlions estimate taste of prey with these chemoreceptors.</p>Published as part of <i>Devetak, Dušan, Lipovšek, Saška & Pabst, Maria-Anna, 2010, Larval morphology of the antlion Neuroleon microstenus (McLachlan, 1898) (Neuroptera, Myrmeleontidae), with notes on larval biology, pp. 55-63 in Zootaxa 2428</i> on pages 56-62, DOI: <a href="http://zenodo.org/record/294037">10.5281/zenodo.294037</a&gt

Larval morphology of the antlion Neuroleon microstenus (McLachlan, 1898) (Neuroptera, Myrmeleontidae), with notes on larval biology

Laval stages of the Mediterranean antlion species Neuroleon microstenus (McLachlan) are described and illustrated. Larvae do not build pitfall traps. They pursue prey by digging in sand backwards and waiting a prey. Second and third instar larvae move backwards or forwards on sand surface, whilst first instar larvae only forwards. Characteristic for the larvae of N. microstenus - like for other non-pit-builders - are prominent eye tubercles and sparse mandibular bristles. On the abdominal tip two bulges occur, each with four digging bristles. On the dorsal side of the head of second and third instar larvae black pigmentation occur forming "V" mark. Campaniform sensilla, sensilla coeloconica and sensilla basiconica are recognized for the first time in antlion larvae