Transition from marine to terrestrial ecologies: changes in olfactory and tritocerebral neuropils in land-living isopods

In addition to the ancestors of insects, representatives of five lineages of crustaceans have colonized land. Whereas insects have evolved sensilla that are specialized to allow the detection of airborne odors and have evolved olfactory sensory neurons that recognize specific airborne ligands, there is so far little evidence for aerial olfaction in terrestrial crustaceans. Here we ask the question whether terrestrial Isopoda have evolved the neuronal substrate for the problem of detecting far-field airborne chemicals. We show that conquest of land of Isopoda has been accompanied by a radical diminution of their first antennae and a concomitant loss of their deutocerebral olfactory lobes and olfactory computational networks. In terrestrial isopods, but not their marine cousins, tritocerebral neuropils serving the second antenna have evolved radical modifications. These include a complete loss of the malacostracan pattern of somatotopic representation, the evolution in some species of amorphous lobes and in others lobes equipped with microglomeruli, and yet in others the evolution of partitioned neuropils that suggest modality-specific segregation of second antenna inputs. Evidence suggests that Isopoda have evolved, and are in the process of evolving, several novel solutions to chemical perception on land and in air.

25-Hydroxyvitamin D in Canadian adults: biological, environmental, and behavioral correlates

SUMMARY

We assessed vitamin D status and its correlates in the population-based Canadian Multicentre Osteoporosis Study (CaMos). Results showed that serum 25-hydroxyvitamin D levels <75 nmol/L were common. Given Canada's high latitude, attention should be given to strategies for enhancing vitamin D status in the population.

INTRODUCTION

Inadequate vitamin D has been implicated as a risk factor for several clinical disorders. We assessed, in a Canadian cohort, vitamin D status and its correlates, based on serum 25-hydroxyvitamin D [25(OH)D], the best functional indicator of vitamin D status.

METHODS

We studied 577 men and 1,335 women 35+ years from seven cities across Canada in the randomly selected, population-based Canadian Multicentre Osteoporosis Study (CaMos). Participants completed a comprehensive questionnaire. Serum 25(OH)D was measured by immunoassay. Multivariate linear regression modeling assessed the association between 25(OH)D and determinants of vitamin D status.

RESULTS

Participants (2.3%) were deficient in 25(OH)D (<27.5 nmol/L); a further 18.1% exhibited 25(OH)D insufficiency (27.5-50 nmol/L). Levels <75 nmol/L were evident in 57.5% of men and 60.7% of women and rose to 73.5% in spring (men) and 77.5% in winter (women); 25(OH)D <50 nmol/L was ≤10% year round for those supplementing with ≥400 IU vitamin D/day but was 43.9% among those not supplementing in winter and spring. The strongest predictors of reduced 25(OH)D for both men and women were winter and spring season, BMI ≥30, non-white ethnicity, and lower vitamin D supplementation and its modification by fall and winter.

CONCLUSIONS

In this national Canadian cohort, vitamin D levels <75 nmol/L were common, particularly among non-white and obese individuals, and in winter and spring. Vitamin D intake through diet and supplementation and maintenance of normal weight are key modifiable factors for enhancing vitamin D status and thus potentially influencing susceptibility to common chronic diseases.

Medico-legal implications of sleep apnoea syndrome: Driving license regulations in Europe

BACKGROUND

Sleep apnoea syndrome (SAS), one of the main medical causes of excessive daytime sleepiness, has been shown to be a risk factor for traffic accidents. Treating SAS results in a normalized rate of traffic accidents. As part of the COST Action B-26, we looked at driving license regulations, and especially at its medical aspects in the European region.

METHODS

We obtained data from Transport Authorities in 25 countries (Austria, AT; Belgium, BE; Czech Republic, CZ; Denmark, DK; Estonia, EE; Finland, FI; France, FR; Germany, DE; Greece, GR; Hungary, HU; Ireland, IE; Italy, IT; Lithuania, LT; Luxembourg, LU; Malta, MT; Netherlands, NL; Norway, EC; Poland, PL; Portugal, PT; Slovakia, SK; Slovenia, SI; Spain, ES; Sweden, SE; Switzerland, CH; United Kingdom, UK).

RESULTS

Driving license regulations date from 1997 onwards. Excessive daytime sleepiness is mentioned in nine, whereas sleep apnoea syndrome is mentioned in 10 countries. A patient with untreated sleep apnoea is always considered unfit to drive. To recover the driving capacity, seven countries rely on a physician's medical certificate based on symptom control and compliance with therapy, whereas in two countries it is up to the patient to decide (on his doctor's advice) to drive again. Only FR requires a normalized electroencephalography (EEG)-based Maintenance of Wakefulness Test for professional drivers. Rare conditions (e.g., narcolepsy) are considered a driving safety risk more frequently than sleep apnoea syndrome.

CONCLUSION

Despite the available scientific evidence, most countries in Europe do not include sleep apnoea syndrome or excessive daytime sleepiness among the specific medical conditions to be considered when judging whether or not a person is fit to drive. A unified European Directive seems desirable.

[18F] FDG-PET/CT as a new and sensitive imaging method for the diagnosis of large vessel vasculitis

OBJECTIVE

To determine the value of the new imaging modality positron-emission tomography/computed tomography (PET/CT) for the diagnosis and re-evaluation of large vessel vasculitis.

METHODS

Thirteen patients newly diagnosed or re-evaluated for suspected clinical disease activity of Takayasu arteritis (TA, 3 patients) or giant cell arteritis (GCA, 10 patients) underwent PET/CT. Clinical activity status, serological markers, and alternative imaging methods were evaluated.

RESULTS

In patients with clinical activity despite nearly normal erythrocyte sedimentation rate (ESR) and C reactive protein (CRP), disease activity could be shown by PET-CT. A long segmental, increased fluoro-deoxyglucose (FDG) uptake in the vessel wall served as confirmation of the vascular inflammation. The aortic arch was involved in all patients with active disease (n=12). In the complementary CT scans, stenotic lesions were found in 8 out of 13 patients. Duplex ultrasonography was performed in 11/13 patients and was positive in nine of these patients at least at one site. Magnetic resonance imaging (MRI) was done for confirmation in 10 patients.

CONCLUSION

Doppler ultrasonography is a very useful and widely available method to confirm a first suspicion of vasculitis, but it has limitations especially at the large thoracic vessels, which are affected in many cases. ESR and CRP alone are not sufficient to evaluate disease activity. The new imaging modality PET/CT provides the additional information. It allows the evaluation of disease activity and vessel morphology as well as the localization of the inflammatory process in the same session.

The expression pattern of four odorant-binding proteins in male and female silk moths, Bombyx mori

Four recombinant odorant-binding proteins of Bombyx mori, pheromone-binding protein (PBP), general odorant-binding protein 1 (GOBP1), general odorant-binding protein 2 (GOBP2) and antennal binding protein X (ABPX), were expressed in E. coli and used to raise polyclonal antisera. Immunoblots of antennal homogenates showed that these antisera were specific. In Western blot analysis and immunocytochemical labelling experiments, the sera against recombinant PBP and GOBP2 of B. mori gave identical results as sera against native PBP and GOBP2 of Antheraea polyphemus, respectively, thus confirming earlier results obtained with the latter. Labelling consecutive cross sections of various sensillum types with all four antisera revealed different labelling patterns in male and female sensilla (s.) trichodea and s. basiconica. Long s. trichodea in males and females represented uniform labelling types, whereas for short s. trichodea, s. intermedia, and s. basiconica a great variety of labelling patterns was observed, some being more common than others. Long s. trichodea, which in males are uniformly tuned to the pheromone components bombykol and bombykal, all strongly expressed PBP; labelling with antisera against the other three odorant-binding proteins hardly was above background, only in some hairs GOBP1 was expressed somewhat more strongly. Long s. trichodea of females, which respond specifically to linalool and benzoic acid, showed a different labelling pattern. Here, we observed strong labelling with antibodies against GOBP2 and medium labelling with anti-GOBP1, sometimes with anti-ABPX. S. basiconica in both sexes most commonly co-expressed GOBP1 and GOBP2, but other patterns were occasionally found, with some of them showing PBP expression, also in females. The great variety of labelling types in short s. trichodea, s. intermedia, and s. basiconica suggests a similar variety of functional subtypes as observed in plant odour-sensitive sensilla of other moth species.

REM sleep behavior disorder: clinical and physiopathological findings

Abnormalities of REM sleep i.e. absence of atonia and abnormal motor control which are described in patients with REM sleep behavior disorder, have induced clinical and physiopathological interest. Initial hypothesis of a simple dysfunction of REM sleep generators has not been confirmed. The prevalence in older subjects and in patients with parkinsonian syndromes suggest that the appearance of the parasomnia is related to alteration in the neurons of pontine area i.e. nucleus peduncolopontine, in which there is an integration of sleep-wake mechanisms and locomotor systems. Controversy surrounds the specificity of absence of atonia in the diagnosis of the parasomnia. Since this polygraphic finding may be present in subjects without any sleep complaint and in patients with initial neurological impairment, diagnosis of the sleep disorders might be allowed only when the polygraphic characteristic of persistent tonus and complex motor behavior are recorded.

Genes encoding candidate pheromone receptors in a moth (Heliothis virescens)

The remarkable responsiveness of male moths to female released pheromones is based on the extremely sensitive and selective reaction of highly specialized sensory cells in the male antennae. These cells are supposed to be equipped with male-specific receptors for pheromonal compounds, however, the nature of these receptors is still elusive. By using a combination of genomic sequence analysis and cDNA-library screening, we have cloned various cDNAs of the tobacco budworm Heliothis virescens encoding candidate olfactory receptors. A comparison of all identified receptor types not only highlighted their overall high degree of sequence diversity but also led to the identification of a small group of receptors sharing >40% identity. In RT-PCR analysis it was found that distinct members of this group were expressed exclusively in the antennae of male moths. In situ hybridization experiments revealed that the male-specific expression of these receptor types was confined to antennal cells located beneath sensillar hair structures (sensilla triochoidea), which have been shown to contain pheromone-sensitive neurons. Moreover, two-color double in situ-hybridization approaches uncovered that cells expressing one of these receptor types were surrounded by cells expressing pheromone-binding proteins, as expected for a pheromone-sensitive sensillum. These findings suggest that receptors like Heliothis receptor 14-16 (HR14-HR16) may render antennal cells responsive to pheromones.

[Cortical arousal, autonomic arousal. Evaluation techniques and clinical importance]

The respiratory disorders expressed by obstructive hypopneas and apneas during sleep, as well as the sequences of crescendo in respiratory effort without hypopneas or apneas which define the upper airway resistance syndrome, terminate with (thanks to) an arousal, defined by EEG changes. In some cases, the activation of the central nervous system is restricted to a sympathetic activation, which has been mainly studied in the cardiovascular area, and is not always accompanied by a cortical arousal. Various approaches (heart rate, blood pressure, pulse transit time, peripheral arterial tonometry) make the identification of sympathetic activation possible. Sympathetic activation seems to be more sensitive than cortical arousal to the stimulations generated by the respiratory system via an activation of mechanoreceptors stimulated by the increased respiratory effort in response to total or partial occlusion of the upper airway. The mechanisms of the cortical or autonomic arousal are not fully understood, but their detection could be a diagnostic tool for the identification of such disorders. Such tools are currently under validation.

A candidate olfactory receptor subtype highly conserved across different insect orders

Candidate olfactory receptors of the moth Heliothis virescens were found to be extremely diverse from receptors of the fruitfly Drosophila melanogaster and the mosquito Anopheles gambiae, but there is one exception. The moth receptor type HR2 shares a rather high degree of sequence identity with one olfactory receptor type both from Drosophila (Dor83b) and from Anopheles (AgamGPRor7); moreover, in contrast to all other receptors, this unique receptor type is expressed in numerous antennal neurons. Here we describe the identification of HR2 homologues in two further lepidopteran species, the moths Antheraea pernyi and Bombyx mori, which share 86-88% of their amino acids. In addition, based on RT-PCR experiments HR2 homologues were discovered in antennal cDNA of the honey bee (Apis mellifera; Hymenoptera), the blowfly (Calliphora erythrocephala; Diptera) and the mealworm (Tenebrio molitor; Coleoptera). Comparison of all HR2-related receptors revealed a high degree of sequence conservation across insect orders. In situ hybridization of antennal sections from the bee and the blowfly support the notion that HR2-related receptors are generally expressed in a very large number of antennal cells. This, together with the high degree of conservation suggests that this unique receptor subtype may fulfill a special function in chemosensory neurons of insects.

In vitro immunomodulatory activity of ruthenium complexes

OBJECTIVE AND DESIGN

We have explored the in vitro immunomodulatory effects of pure ruthenium red and a series of pyridine and imidazole substituted ruthenium complexes (RCs).

MATERIAL

Human peripheral blood lymphocytes and purified T cells were used in these studies along with various cell lines.

METHODS

Cells were treated with dilutions of RCs and assessed in various assays of immune function, cytotoxicity and cell cycle progression.

RESULTS

RCs efficiently blocked T cell receptor (TCR)-mediated stimulation (IC(50)'s in the low nM range) of human peripheral blood lymphocytes (hPBL) by various agents, including tetanus toxoid, alloantigens, superantigens, and receptor-specific antibodies. RCs are not cytotoxic to T cells. Antiproliferative activity was also observed for B cells. Some non-lymphoid cell lines or primary cultures showed sensitivity to the RCs, but only at higher concentrations. The inhibitory effect on human T cells was assessed and demonstrated at the level of proliferation (DNA synthesis), IL-2 secretion, and IL-2 receptor (CD25) upregulation. RCs also inhibited IL-2-mediated proliferation of antigen-induced T-cell blasts and the IL-2-dependent T cell line Kit-225. Cell cycle analysis indicates that RCs inhibit the progression of activated T cells from G(0)/G(1) to S phase.

CONCLUSIONS

Since the mechanism of T cell inhibition by RCs appears to be different than that of rapamycin (RAP) or cyclosporin A (CsA), they may provide a new tool to investigate intracellular signaling in T cells, and may present novel opportunities for immunosuppression

[Study of the real situation of improvement by Zopiclone in treatment of insomnia among persons working during night shifts]

We investigated the effect of adapted management of sleep on the duration and quality of sleep in shift workers working the night shift. Twenty-nine shift workers suffering from insomnia were included and treated with zopiclone (7.5mg/day) or placebo according to a random double-blind protocol. Patients completed a sleep diary and a wrist actigraph was used to evaluate episodes of rest/activity. A self-administered subjective sleep questionnaire was filled out just after awakening. Zopicone was found to increase the duration of sleep significantly (p<0.05) over the baseline duration after the first and second night on duty. Subjective estimation of sleep was better in patients taking zopiclone who exhibited a smaller number of shorter awakening episodes.

IN CONCLUSION

zopiclone improves the quality and duration of sleep in shift workers suffering from insomnia.

Identity and expression pattern of chemosensory proteins in Heliothis virescens (Lepidoptera, Noctuidae)

Analyzing the chemosensory organs of the moth Heliothis virescens, three proteins belonging to the family of insect chemosensory proteins (CSPs) have been cloned; they are called HvirCSP1, HvirCSP2 and HvirCSP3. The HvirCSPs show about 50% identity between each other and 30-76% identity to CSPs from other species. Overall, they are rather hydrophilic proteins but include a conserved hydrophobic motif. Tissue distribution and temporal expression pattern during the last pupal stages were assessed by Northern blots. HvirCSP mRNAs were detected in various parts of the adult body with a particular high expression level in legs. The expression of HvirCSP1 in legs started early during adult development, in parallel with the appearance of the cuticle. HvirCSP1 mRNA was detectable five days before eclosion (day E-5), increased dramatically on day E-3 and remained at high level into adult life. The tissue distribution and the time course of appearance of HvirCSPs are in agreement with a possible role in contact chemosensation.

Antennal SNMPs (sensory neuron membrane proteins) of Lepidoptera define a unique family of invertebrate CD36-like proteins

SNMP1-Apol is an antennal-specific protein of the wild silk moth Antheraea polyphemus; the protein is abundantly expressed and localized to the receptor membranes of sex-pheromone specific olfactory sensory neurons (OSNs). SNMP1-Apol is thought to function in odor detection based on its olfactory-specific expression, localization within OSNs, developmental time of expression, and apparent homology to the CD36 family of membrane-bound receptor proteins. In the current study, SNMP1-Apol homologues were identified from the moths Bombyx mori, Heliothis virescens, and Manduca sexta. These species posses antennal mRNAs encoding proteins with amino acid sequence identities ranging from 75-80%; these proteins are collectively designated SNMP1. A second M. sexta SNMP homologue, previously identified and partially sequenced [Robertson et al.: Insect Mol Biol 8:501-518, 1999] was fully sequenced and characterized. The encoded protein shares only 26-27% sequence identity with the SNMP1 proteins, and is thus designated SNMP2-Msex. The SNMP sequences were used to identify 14 and four possible homologues in Drosophila melanogaster and Caenorhabditis elegans genome databases, respectively; thus, greatly expanding CD36 family membership among the invertebrate lineages. Despite their sequence difference, SNMP1-Msex and SNMP2-Msex expression is localized to OSNs and occurs simultaneously with the onset of olfactory function. These findings suggest that SNMPs play a central role in odor detection in insects, and that the CD36 gene family is widely represented among animal phyla. The SNMPs are the only identified neuronal members of the CD36 family, and as such expand the activities of this gene family into roles influencing brain function and behavioral action.

In vitro evidence that immunuaffinity-purified MOG contains immunogenic quantities of contaminating mouse IgG; techniques for producing Ig-free MOG

Myelin oligodendrocyte glycoprotein (MOG) has attracted considerable attention due to its possible role in multiple sclerosis (MS). Previous studies have shown that MOG-reactive T cells are more commonly detected in MS patients than controls. In this report, we studied human MOG-reactive T cell clones generated from healthy individuals as well as MS patients. Our results indicate that immunoaffinity-purified MOG, which was routinely used in prior studies, is contaminated by anti-MOG antibody (mouse IgG), despite the inability to detect IgG by Western blotting. Here, we used continuous SDS-PAGE, which enabled us to isolate highly purified MOG devoid of contaminating mouse IgG.

The obesity-hypoventilation syndrome revisited: a prospective study of 34 consecutive cases

STUDY OBJECTIVES

Obesity has many detrimental effects on the respiratory function and may lead to chronic hypoventilation in some patients, an association known as the obesity-hypoventilation syndrome (OHS). In many cases, patients with OHS also have sleep apneas. Hereafter, we describe several features of a cohort (n = 34) of patients with OHS and show the comparisons with a large cohort (n = 220) of patients with obstructive sleep apnea syndrome (OSAS). We compare also OHS patients with a group of patients with the association of OSAS and COPD, also known as "overlap" patients.

DESIGN

Descriptive analysis of prospectively collected clinical data.

SETTING

Respiratory care unit and sleep laboratory of university hospital.

RESULTS

In OHS patients, OSAS was present in most of the cases (23 of 26 patients). However, in three patients, OHS was not associated with OSAS, showing that obesity per se may lead to chronic hypoventilation. As expected by definition, OHS patients had, on average the worst diurnal arterial blood gas measurements, compared to the other groups. For the OHS patients, the mean diurnal PaO(2) was 59 +/- 7 mm Hg, which was significantly different from the PaO(2) of the OSAS patients (75 +/- 10 mm Hg; p = 0,001) but also from the overlap patients (66 +/- 10 mm Hg; p = 0.015). Pulmonary hypertension (ie, mean pulmonary artery pressure > 20 mm Hg) was more frequent in OHS patients than in "pure" OSAS patients (58% vs 9%; p = 0.001).

CONCLUSION

Patients with OSAS and chronic respiratory insufficiency had in most cases an associated OHS or COPD. Patients with OHS were older than patients with pure OSAS. They had mild-to-moderate degrees of restrictive ventilatory pattern due to obesity. Severe gas exchange impairment and pulmonary hypertension were quite frequent. The association of OHS and OSAS was the rule. However, in three patients, OHS was not associated with OSAS, suggesting that OHS is an autonomous disease.

Revisiting the specificity of Mamestra brassicae and Antheraea polyphemus pheromone-binding proteins with a fluorescence binding assay

Pheromone-binding proteins (PBPs), located in the sensillum lymph of pheromone-responsive antennal hairs, are thought to transport the hydrophobic pheromones to the chemosensory membranes of olfactory neurons. It is currently unclear what role PBPs may play in the recognition and discrimination of species-specific pheromones. We have investigated the binding properties and specificity of PBPs from Mamestra brassicae (MbraPBP1), Antheraea polyphemus (ApolPBP1), Bombyx mori (BmorPBP), and a hexa-mutant of MbraPBP1 (Mbra1-M6), mutated at residues of the internal cavity to mimic that of BmorPBP, using the fluorescence probe 1-aminoanthracene (AMA). AMA binds to MbraPBP1 and ApolPBP1, however, no binding was observed with either BmorPBP or Mbra1-M6. The latter result indicates that relatively limited modifications to the PBP cavity actually interfere with AMA binding, suggesting that AMA binds in the internal cavity. Several pheromones are able to displace AMA from the MbraPBP1- and ApolPBP1-binding sites, without, however, any evidence of specificity for their physiologically relevant pheromones. Moreover, some fatty acids are also able to compete with AMA binding. These findings bring into doubt the currently held belief that all PBPs are specifically tuned to distinct pheromonal compounds.

Detection and removal of an artefact fatty acid from the binding site of recombinant Bombyx mori pheromone-binding protein

Recombinant Bombyx mori pheromone-binding protein (PBP), purified from an Escherichia coli expression system, has been found to contain (11Z)-octadecenoic acid (cis-vaccenic acid) as an artefact ligand. An efficient delipidation procedure is described to overcome what would appear to be a general problem with recombinant lepidopteran PBPs.