Respiratory rhythms in stingless bee workers: circadian and ultradian components throughout adult development

The workers of the stingless bee, Melipona quadrifasciata, assume different tasks during their adult life. Newly emerged individuals remain inside the nest, without contact with the external environment. Maturing workers go to more peripheral regions and only the oldest, the foragers, leave the nest. As this diversity of activities implies different metabolic patterns, oxygen consumption has been measured in workers of three different ages: 24-48 h (nurses), 10-15 days (builders), and older than 25 days (foragers). Oxygen consumption of individually isolated workers was determined by intermittent respirometry, under constant darkness and temperature of 25 +/- 1 degrees C. Sets of 24-h measurements were obtained from individuals belonging to each of the three worker groups. Rhythmicity has been assessed in the daily (24 h) and ultradian (5-14 h) domains. This experimental design allowed detection of endogenous rhythms without the influence of the social group and without inflicting stress on the individuals, as would be caused by their longer isolation from the colony. Significant 24-h rhythms in oxygen consumption were present in nurses, builders and foragers; therefore, workers are rhythmic from the age of 24-48 h. However, the amplitude of the circadian rhythm changed according to age: nurses showed the lowest values, while foragers consistently presented the largest ones, about ten times larger than the amplitude of nurses` respiratory rhythm. Ultradian frequencies were detected for all worker groups, the power and frequencies of which varied little with age. This means that the ultradian strength was relatively larger in nurses and apparently maintains some relationship with the queen`s oviposition episodes.

Attachment Theory Shaping Adult Development: Impact on Mentoring Experiences

Mentoring is increasingly used for career and psychosocial development. Very few studies that have investigated the role of individual differences in mentoring relationships have addressed the attachment styles of mentors and protégés. The purpose of this study is to find the connections between attachment styles, adult development, and mentoring experiences.

Evolution of additive and nonadditive genetic variance in development time along a cline in Drosophila serrata

Latitudinal clines provide natural systems that may allow the effect of natural selection on the genetic variance to be determined. Ten clinal populations of Drosophila serrata collected from the eastern coast of Australia were used to examine clinal patterns in the trait mean and genetic variance of the life-history trait egg-to-adult development time. Development time significantly lengthened from tropical areas to temperate areas. The additive genetic variance for development time in each population was not associated with latitude but was associated with the population mean development time. Additive genetic variance tended to be larger in populations with more extreme development times and appeared to be consistent with allele frequency change. In contrast, the nonadditive genetic variance was not associated with the population mean but was associated with latitude. Levels of nonadditive genetic variance were greatest in the region of the cline where the gradient in the change in mean was greatest, consistent with Barton's (1999) conjecture that the generation of linkage disequilibrium may become an important component of the genetic variance in systems with a spatially varying optimum.

Development of a new tool for assessing health-related quality of life in patients with primary hyperparathyroidism.

BACKGROUND Several studies in recent years have evaluated Health Related Quality of Life (HRQoL) of patients with primary hyperparathyroidism (PHPT). No disease specific questionnaires are available to assess the impact of the disease. The aim of this research is to describe the development of a new disease specific Quality of Life (QoL) questionnaire for use specifically with PHPT patients. METHODS A conceptual model was developed describing the impact of the disease and its symptoms on QoL domains. A literature review was conducted to identify the most relevant domains. A focus group with experts was used to validate the domains; 24 patients were also interviewed to complement the information from the patient's perspective. A content analysis of the interviews was performed to identify items related with the impact of the disease, leading to PHPQoL-V.1 which was presented to a sample of 67 patients. Reliability was assessed by Cronbach's coefficient alpha and item-total score correlations. Validity was assessed by a factor analysis performed to determine the number of domains. Rasch analysis was carried out in order to refine the questionnaire items. RESULTS 259 items were extracted from the interviews that were subsequently reduced to 34 items. Cronbach's coefficient alpha was 0.92. The factor analysis extracted two domains (physical and emotional). After Rasch analysis the questionnaire PHPQoL-V.2 kept 16 items (9 physical and 7 emotional). The questionnaire was developed in a Spanish population and the final version was translated to English through translation and back-translation. CONCLUSION The first disease specific HRQoL questionnaire for PHPT patients (PHPQoL-16) has been developed. Validation studies designed to assess measurement properties of this tool are currently underway.

Development and evaluation of a shaken baby syndrome prevention program.

OBJECTIVE: To evaluate parents' and nurses' opinions regarding the adequacy of an educational program on shaken baby syndrome: the Perinatal Shaken Baby Syndrome Prevention Program (PSBSPP). DESIGN: Qualitative and quantitative assessments in the form of interviews and questionnaires administered in French. SETTING: Two birthing institutions in Montréal, QC, Canada: a university hospital and a regional center. PARTICIPANTS: Two hundred and sixty-three parents (73.8% mothers, 26.2% fathers) received the intervention after the birth of their child, and 69 nurses administered it. METHODS: Parents' and nurses' assessments of the adequacy and relevance of the program and nurses' assessments of the training they received to administer the program were evaluated. RESULTS: Both parents and nurses supported this initiative. Most parents appreciated the usefulness of the information. Nurses believed the program was adequate, and their training to deliver the program was satisfactory. All participants reported that the program was highly relevant, especially for new parents. CONCLUSION: The Perinatal Shaken Baby Syndrome Prevention Program achieves the goals of (a) increasing parents' knowledge about infant crying, anger, and shaken baby syndrome and (b) helping parents identify coping strategies. The relevance of introducing the PSBSPP in all birthing institutions is supported. Future studies should focus on vulnerable and culturally diverse populations, and longitudinal follow-up could help determine if the PSBSPP reduces the incidence of shaken baby syndrome.

Development and validation of a clinical decision rule for the diagnosis of influenza.

INTRODUCTION: A clinical decision rule to improve the accuracy of a diagnosis of influenza could help clinicians avoid unnecessary use of diagnostic tests and treatments. Our objective was to develop and validate a simple clinical decision rule for diagnosis of influenza. METHODS: We combined data from 2 studies of influenza diagnosis in adult outpatients with suspected influenza: one set in California and one in Switzerland. Patients in both studies underwent a structured history and physical examination and had a reference standard test for influenza (polymerase chain reaction or culture). We randomly divided the dataset into derivation and validation groups and then evaluated simple heuristics and decision rules from previous studies and 3 rules based on our own multivariate analysis. Cutpoints for stratification of risk groups in each model were determined using the derivation group before evaluating them in the validation group. For each decision rule, the positive predictive value and likelihood ratio for influenza in low-, moderate-, and high-risk groups, and the percentage of patients allocated to each risk group, were reported. RESULTS: The simple heuristics (fever and cough; fever, cough, and acute onset) were helpful when positive but not when negative. The most useful and accurate clinical rule assigned 2 points for fever plus cough, 2 points for myalgias, and 1 point each for duration <48 hours and chills or sweats. The risk of influenza was 8% for 0 to 2 points, 30% for 3 points, and 59% for 4 to 6 points; the rule performed similarly in derivation and validation groups. Approximately two-thirds of patients fell into the low- or high-risk group and would not require further diagnostic testing. CONCLUSION: A simple, valid clinical rule can be used to guide point-of-care testing and empiric therapy for patients with suspected influenza.

DIFFERENTIATION OF DROSOPHILA-SERIDO (ISOFEMALE LINE A95F3) AND D-KOEPFERAE (ISOFEMALE LINE B20D2) - REPRODUCTIVE ISOLATION, DEVELOPMENT TIME AND POLYTENE CHROMOSOME-BANDING PATTERNS

Drosophila serido is considered to be a superspecies consisting of two species: D. serido, from Brazil and D. koepferae from Argentina and Bolivia. However this probably does not express the entire evolutionary complexity of its populations. Isofemale lines A95F3 (from Brazil) and B20D2 (from Argentina), at present representing, respectively, the first and second species, were analyzed for fertility and fecundity in pair-mating intracrosses and intercrosses, as well as for development time, banding patterns and asynapsis of polytene chromosomes in the isofemale lines and their hybrids.Although variations in experimental conditions resulted in some variability in the results, in general A95F3 fertility and fecundity were lower than in B20D2. Intercrosses of A95F3 females and B20D2 males showed lower fertility and fecundity than the reciprocal crosses, following more closely characteristics of the mother strains. This is in contrast to the results obtained by Fontdevilla et al. (An. Entomol. Soc. Amer. 81: 380-385, 1988) and may be due to the different geographic origin of D. serido strains they used in crosses to B20D2. This difference and others cited in the literature relative to aedeagus morphology, karyotype characteristics, inversion polymorphisms and reproductive isolation strongly indicate that A95F3 and D. serido from the State of Bahia, Brazil are not a single evolutionary entity, reinforcing the idea of greater complexity of the superspecies D. serido than is known today.The reproductive isolation mechanisms found operating between A95F3 and B20D2 were prezygotic and postzygotic, the latter included mortality at the larvae stage in both directions of crosses and sterility of male hybrids in intercrosses involving B20D2 females and A95F3 males. The two isofemale lines differed in egg-adult development time, which was also differently affected by culture medium composition.A95F3 and B20D2 also showed differences in the banding patterns of proximal regions of polytene chromosomes 2, 3 and X, a fixed inversion in chromosome 3 (here named 3t), apparently not described previously, and a high degree of asynapsis in hybrids.These observations, especially those related to reproductive isolation and chromosomal differentiation (including the karyotype, previously described, and the differentiation of banding patterns, described in this paper), as well as the extensive asynapsis observed in hybrids reinforces the distinct species status of A95F3 and B20D2 isofemale lines.

Development and application of a highly selective biomimetic sensor for detection of captopril, an important ally in hypertension control

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Polydnavirus DNA of the braconid wasp Chelonus inanitus is integrated in the wasp's genome and excised only in later pupal and adult stages of the female

Many endoparasitic wasps inject, along with the egg, polydnavirus into their insect hosts, the virus being a prerequisite for successful parasitoid development. The genome of polydnaviruses consists of multiple circular dsDNA molecules of variable size. We show for a 12 kbp segment of the braconid Chelonus inanitus (CiV12) that it is integrated into the wasp genome. This is the first direct demonstration of integration for a bracovirus. PCR data indicated that the integrated form of CiV12 was present in all male and female stages investigated while the excised circular virus DNA only appeared in females after a specific stage in pupal-adult development. The data also indicated that after excision of virus DNA the genomic DNA was rejoined. This has not yet been reported for any polydnavirus. Sequence analyses in the junction regions revealed the presence of an imperfect consensus sequence of 15 nucleotides in CiV12, in each terminus of the integrated virus DNA and in the rejoined genomic DNA. Within these repeats two sequence types (ATA, TAC) were observed in the various virus clones and in the clones encompassing the rejoined genomic DNA; they corresponded to the sequence type in the right and left junction, respectively. To explain this, we propose a model of virus DNA replication in which the genomic DNA is folded to juxtapose the direct repeat of the left with that of the right junction; recombination at specific sites would then yield the two types of virus and rejoined genomic DNA.

The insect neuropeptide prothoracicotropic hormone is released with a daily rhythm: re-evaluation of its role in development.

Prothoracicotropic hormone (PTTH) is the central cerebral neurohormone in insect development. Its release has been believed for decades to be confined to one (or two) critical moments early in each developmental stage at which time it triggers prolonged activation of the prothoracic glands to synthesize and release the steroid molting hormones (ecdysteroids), which elicit developmental responses in target tissues. We used an in vitro assay for PTTH released from excised brains of the bug Rhodnius prolixus and report that release of PTTH does occur at the expected time on day 6, but that this release is merely the first in a daily rhythm of release that continues throughout most of the 21 days of larval-adult development. This finding, together with reports of circadian control of ecdysteroid synthesis and titer throughout this time, raises significant challenges to several features of the current understanding of the hormonal control of insect development. New questions are raised concerning the function(s) of PTTH, its relationship with the prothoracic glands, and the significance of circadian rhythmicity throughout this endocrine axis. The significance of the reported observations derives from the set of entirely new questions they raise concerning the regulation of insect development.

The Genetics of Success: How Single-Nucleotide Polymorphisms Associated With Educational Attainment Relate to Life-Course Development.

A previous genome-wide association study (GWAS) of more than 100,000 individuals identified molecular-genetic predictors of educational attainment. We undertook in-depth life-course investigation of the polygenic score derived from this GWAS using the four-decade Dunedin Study (N = 918). There were five main findings. First, polygenic scores predicted adult economic outcomes even after accounting for educational attainments. Second, genes and environments were correlated: Children with higher polygenic scores were born into better-off homes. Third, children's polygenic scores predicted their adult outcomes even when analyses accounted for their social-class origins; social-mobility analysis showed that children with higher polygenic scores were more upwardly mobile than children with lower scores. Fourth, polygenic scores predicted behavior across the life course, from early acquisition of speech and reading skills through geographic mobility and mate choice and on to financial planning for retirement. Fifth, polygenic-score associations were mediated by psychological characteristics, including intelligence, self-control, and interpersonal skill. Effect sizes were small. Factors connecting DNA sequence with life outcomes may provide targets for interventions to promote population-wide positive development.

Changes in integument structure during the imaginal molt of the honey bee

The changing pattern of developing cuticle and associated epidermis is described during the imaginal molt in the honey bee. Observations began immediately after the pupal molt, and included histological analyses of the integument during apolysis and the subsequent deposition and differentiation of the adult cuticle. Apolysis coincides with a marked increase in the thickness and reorganization of the epidermal layer, reflecting changes in cell structure. The epidermis remains thickened during the period of cuticle deposition, suggesting intense biosynthetic activity, but turns into a very thin layer during cuticle differentiation, clearly indicating that secretory activity for cuticle formation is terminating. The thoracic cuticle differentiates earlier and becomes thicker than the abdominal. The observed changes in integument structure provide insights that permit an improved physiological characterization for staging pupal and pharate adult development.

Developmental characterization, function and regulation of a Laccase2 encoding gene in the honey bee, Apis mellifera (Hymenoptera, Apinae)

In insects, exoskeleton (cuticle) formation at each molt cycle includes complex biochemical pathways wherein the laccase enzymes (EC 1.10.3.2) may have a key role. We identified an Amlac2 gene that encodes a laccase2 in the honey bee, Apis mellifera, and investigated its function in exoskeleton differentiation. The Amlac2 gene consists of nine exons resulting in an ORE of 2193 nucleotides. The deduced translation product is a 731 amino acid protein of 81.5 kDa and a pl of 6.05. Amlac2 is highly expressed in the integument of pharate adults, and the expression precedes the onset of cuticle pigmentation and the intensification of sclerotization. In accordance with the temporal sequence of exoskeleton differentiation from anterior to posterior direction, the levels of Amlac2 transcript increase earlier in the thoracic than in the abdominal integument. The gene expression lasts even after the bees emerge from brood cells and begin activities in the nest, but declines after the transition to foraging stage, suggesting that maturation of the exoskeleton is completed at this stage. Post-transcriptional knockdown of Amlac2 gene expression resulted in structural abnormalities in the exoskeleton and drastically affected adult eclosion. By setting a ligature between the thorax and abdomen of early pupae we could delay the increase in hemolymph ecdysteroid levels in the abdomen. This severely impaired the increase in Amlac2 transcript levels and also the differentiation of the abdominal exoskeleton. Taken together, these results indicate that Amlac2 expression is controlled by ecdysteroids and has a critical role in the differentiation of the adult exoskeleton of honey bees. (C) 2010 Elsevier Ltd. All rights reserved.

Life cycle and reproductive patterns of Triatoma rubrovaria (Blanchard, 1843) (Hemiptera: Reduviidae) under constant and fluctuating conditions of temperature and humidity

The aim of this study was to evaluate the temperature and relative humidity influence in the life cycle, mortality and fecundity patterns of Triatoma rubrovaria. Four cohorts with 60 recently laid eggs each were conformed. The cohorts were divided into two groups. In the controlled conditions group insects were maintained in a dark climatic chamber under constant temperature and humidity, whereas triatomines of the ambiental temperature group were maintained at room temperature. Average incubation time was 15.6 days in the controlled conditions group and 19.1 days in the ambiental temperature. In group controlled conditions the time from egg to adult development lasted 10 months while group ambiental temperature took four months longer. Egg eclosion rate was 99.1% and 98.3% in controlled conditions and ambiental temperature, respectively. Total nymphal mortality in controlled conditions was 52.6% whereas in ambiental temperature was 51.8%. Mean number of eggs/female was 817.6 controlled conditions and 837.1 ambiental temperature. Fluctuating temperature and humidity promoted changes in the life cycle duration and in the reproductive performance of this species, although not in the species mortality.