Antennal sensilla of two female anopheline sibling species with differing host ranges

BACKGROUND: Volatile odors are important sensory inputs that shape the behaviour of insects, including agricultural pests and disease vectors. Anopheles gambiae s.s. is a highly anthropophilic mosquito and is the major vector for human malaria in sub-Sahara Africa, while Anopheles quadriannulatus, largely due to its zoophilic behaviour, is considered a non-vector species in the same region. Careful studies of olfaction in these sibling species may lead to insights about the mechanisms that drive host preference behaviour. In the present study, the external anatomy of the antenna, the principle olfactory organ in the female mosquito of both species, was examined as an initial step toward more detailed comparisons. METHODS: Scanning electron and light microscopy were used to examine the antennae ultrastructures of adult female An. gambiae s.s. and An. quadriannulatus. Sensory structures, called sensilla, were categorized and counted; their distributions are reported here as well as densities calculated for each species. RESULTS: Both An. gambiae s.s. and An. quadriannulatus bear five classes of sensilla on their antennae: chaetica (bristles), trichodea (hairs), basiconica (pegs), coeloconica (pitted pegs), and ampullacea (pegs in tubes). Female An. quadriannulatus antennae have approximately one-third more sensilla, and a proportionally larger surface area, than female An. gambiae s.s. antennae. CONCLUSION: The same types of sensilla are found on the antennae of both species. While An. quadriannulatus has greater numbers of each sensilla type, sensilla densities are very similar for each species, suggesting that other factors may be more important to such olfactory-driven behaviours as host preference

Balance in single-limb stance after surgically treated ankle fractures: a 14-month follow-up

BACKGROUND: The maintenance of postural control is fundamental for different types of physical activity. This can be measured by having subjects stand on one leg on a force plate. Many studies assessing standing balance have previously been carried out in patients with ankle ligament injuries but not in patients with ankle fractures. The aim of this study was to evaluate whether patients operated on because of an ankle fracture had impaired postural control compared to an uninjured age- and gender-matched control group. METHODS: Fifty-four individuals (patients) operated on because of an ankle fracture were examined 14 months postoperatively. Muscle strength, ankle mobility, and single-limb stance on a force-platform were measured. Average speed of centre of pressure movements and number of movements exceeding 10 mm from the mean value of centre of pressure were registered in the frontal and sagittal planes on a force-platform. Fifty-four age- and gender-matched uninjured individuals (controls) were examined in the single-limb stance test only. The paired Student t-test was used for comparisons between patients' injured and uninjured legs and between side-matched legs within the controls. The independent Student t-test was used for comparisons between patients and controls. The Chi-square test, and when applicable, Fisher's exact test were used for comparisons between groups. Multiple logistic regression was performed to identify factors associated with belonging to the group unable to complete the single-limb stance test on the force-platform. RESULTS: Fourteen of the 54 patients (26%) did not manage to complete the single-limb stance test on the force-platform, whereas all controls managed this (p < 0.001). Age over 45 years was the only factor significantly associated with not managing the test. When not adjusted for age, decreased strength in the ankle plantar flexors and dorsiflexors was significantly associated with not managing the test. In the 40 patients who managed to complete the single-limb stance test no differences were found between the results of patients' injured leg and the side-matched leg of the controls regarding average speed and the number of centre of pressure movements. CONCLUSION: One in four patients operated on because of an ankle fracture had impaired postural control compared to an age- and gender-matched control group. Age over 45 years and decreased strength in the ankle plantar flexors and dorsiflexors were found to be associated with decreased balance performance. Further, longitudinal studies are required to evaluate whether muscle and balance training in the rehabilitation phase may improve postural control

Nitrate regulates floral induction in Arabidopsis, acting independently of light, gibberellin and autonomous pathways

The transition from vegetative growth to reproduction is a major developmental event in plants. To maximise reproductive success, its timing is determined by complex interactions between environmental cues like the photoperiod, temperature and nutrient availability and internal genetic programs. While the photoperiod- and temperature- and gibberellic acid-signalling pathways have been subjected to extensive analysis, little is known about how nutrients regulate floral induction. This is partly because nutrient supply also has large effects on vegetative growth, making it difficult to distinguish primary and secondary influences on flowering. A growth system using glutamine supplementation was established to allow nitrate to be varied without a large effect on amino acid and protein levels, or the rate of growth. Under nitrate-limiting conditions, flowering was more rapid in neutral (12/12) or short (8/16) day conditions in C24, Col-0 and Laer. Low nitrate still accelerated flowering in late-flowering mutants impaired in the photoperiod, temperature, gibberellic acid and autonomous flowering pathways, in the fca co-2 ga1-3 triple mutant and in the ft-7 soc1-1 double mutant, showing that nitrate acts downstream of other known floral induction pathways. Several other abiotic stresses did not trigger flowering in fca co-2 ga1-3, suggesting that nitrate is not acting via general stress pathways. Low nitrate did not further accelerate flowering in long days (16/8) or in 35S::CO lines, and did override the late-flowering phenotype of 35S::FLC lines. We conclude that low nitrate induces flowering via a novel signalling pathway that acts downstream of, but interacts with, the known floral induction pathways

Estimating the Extent of Vaccine-Derived Poliovirus Infection

BACKGROUND: Eight outbreaks of paralytic polio attributable to circulating vaccine-derived poliovirus (cVDPV) have highlighted the risks associated with oral poliovirus vaccine (OPV) use in areas of low vaccination coverage and poor hygiene. As the Polio Eradication Initiative enters its final stages, it is important to consider the extent to which these viruses spread under different conditions, so that appropriate strategies can be devised to prevent or respond to future cVDPV outbreaks. METHODS AND FINDINGS: This paper examines epidemiological (temporal, geographic, age, vaccine history, social group, ascertainment), and virological (type, genetic diversity, virulence) parameters in order to infer the numbers of individuals likely to have been infected in each of these cVDPV outbreaks, and in association with single acute flaccid paralysis (AFP) cases attributable to VDPVs. Although only 114 virologically-confirmed paralytic cases were identified in the eight cVDPV outbreaks, it is likely that a minimum of hundreds of thousands, and more likely several million individuals were infected during these events, and that many thousands more have been infected by VDPV lineages within outbreaks which have escaped detection. CONCLUSIONS: Our estimates of the extent of cVDPV circulation suggest widespread transmission in some countries, as might be expected from endemic wild poliovirus transmission in these same settings. These methods for inferring extent of infection will be useful in the context of identifying future surveillance needs, planning for OPV cessation and preparing outbreak response plans

Composition of Human Skin Microbiota Affects Attractiveness to Malaria Mosquitoes

The African malaria mosquito Anopheles gambiae sensu stricto continues to play an important role in malaria transmission, which is aggravated by its high degree of anthropophily, making it among the foremost vectors of this disease. In the current study we set out to unravel the strong association between this mosquito species and human beings, as it is determined by odorant cues derived from the human skin. Microbial communities on the skin play key roles in the production of human body odour. We demonstrate that the composition of the skin microbiota affects the degree of attractiveness of human beings to this mosquito species. Bacterial plate counts and 16S rRNA sequencing revealed that individuals that are highly attractive to An. gambiae s.s. have a significantly higher abundance, but lower diversity of bacteria on their skin than individuals that are poorly attractive. Bacterial genera that are correlated with the relative degree of attractiveness to mosquitoes were identified. The discovery of the connection between skin microbial populations and attractiveness to mosquitoes may lead to the development of new mosquito attractants and personalized methods for protection against vectors of malaria and other infectious diseases

Odorant-Binding Proteins of the Malaria Mosquito Anopheles funestus sensu stricto

is one of the major malaria vector species in sub-Saharan Africa. Olfaction is essential in guiding mosquito behaviors. Odorant-binding proteins (OBPs) are highly expressed in insect olfactory tissues and involved in the first step of odorant reception. An improved understanding of the function of malaria mosquito OBPs may contribute to identifying new attractants/repellents and assist in the development of more efficient and environmentally friendly mosquito controlling strategies. female antennae. To compare the absolute efficiency/potency of these chemicals, corrections were made for differences in volatility by determining the exact amount in a stimulus puff. Fourteen AfunOBP genes were cloned and their expression patterns were analyzed. AfunOBP1, 3, 7, 20 and 66 showed olfactory tissue specificity by reverse transcriptase PCR (RT-PCR). Quantitative real-time PCR (qRT-PCR) analysis showed that among olfactory-specific OBPs, AfunOBP1 and 3 are the most enriched OBPs in female antennae. Binding assay experiments showed that at pH 7, AfunOBP1 significantly binds to 2-undecanone, nonyl acetate, octyl acetate and 1-octen-3-ol but AfunOBP3, which shares 68% identify with AfunOBP1 at amino acid level, showed nearly no binding activity to the selected 12 EAG-active odorant compounds. olfactory system, and help developing new mosquito control strategies to reduce malaria transmission

Mitochondrial Disease in Autism Spectrum Disorder Patients: A Cohort Analysis

Previous reports indicate an association between autism spectrum disorders (ASD) and disorders of mitochondrial oxidative phosphorylation. One study suggested that children with both diagnoses are clinically indistinguishable from children with idiopathic autism. There are, however, no detailed analyses of the clinical and laboratory findings in a large cohort of these children. Therefore, we undertook a comprehensive review of patients with ASD and a mitochondrial disorder.We reviewed medical records of 25 patients with a primary diagnosis of ASD by DSM-IV-TR criteria, later determined to have enzyme- or mutation-defined mitochondrial electron transport chain (ETC) dysfunction. Twenty-four of 25 patients had one or more major clinical abnormalities uncommon in idiopathic autism. Twenty-one patients had histories of significant non-neurological medical problems. Nineteen patients exhibited constitutional symptoms, especially excessive fatigability. Fifteen patients had abnormal neurological findings. Unusual developmental phenotypes included marked delay in early gross motor milestones (32%) and unusual patterns of regression (40%). Levels of blood lactate, plasma alanine, and serum ALT and/or AST were increased at least once in 76%, 36%, and 52% of patients, respectively. The most common ETC disorders were deficiencies of complex I (64%) and complex III (20%). Two patients had rare mtDNA mutations of likely pathogenicity.Although all patients' initial diagnosis was idiopathic autism, careful clinical and biochemical assessment identified clinical findings that differentiated them from children with idiopathic autism. These and prior data suggest a disturbance of mitochondrial energy production as an underlying pathophysiological mechanism in a subset of individuals with autism

Pathogenic <i>SPTBN1</i> variants cause an autosomal dominant neurodevelopmental syndrome

SPTBN1 encodes βII-spectrin, the ubiquitously expressed β-spectrin that forms micrometer-scale networks associated with plasma membranes. Mice deficient in neuronal βII-spectrin have defects in cortical organization, developmental delay and behavioral deficiencies. These phenotypes, while less severe, are observed in haploinsufficient animals, suggesting that individuals carrying heterozygous SPTBN1 variants may also show measurable compromise of neural development and function. Here we identify heterozygous SPTBN1 variants in 29 individuals with developmental, language and motor delays; mild to severe intellectual disability; autistic features; seizures; behavioral and movement abnormalities; hypotonia; and variable dysmorphic facial features. We show that these SPTBN1 variants lead to effects that affect βII-spectrin stability, disrupt binding to key molecular partners, and disturb cytoskeleton organization and dynamics. Our studies define SPTBN1 variants as the genetic basis of a neurodevelopmental syndrome, expand the set of spectrinopathies affecting the brain and underscore the critical role of βII-spectrin in the central nervous system