Effect of nutrition improvement project on morbidity from infectious diseases in preschool children in Vietnam: comparison with control commune.

OBJECTIVE: To evaluate the effect of a nutrition improvement project based on home garden production and nutrition education on morbidity from acute respiratory infection and diarrhoeal disease in preschool children. DESIGN: The morbidity survey comprised five data collections undertaken by trained interviewers to ascertain the incidence and severity of respiratory infections and the incidence of diarrhoeal disease in children in two communes. SETTING: A project commune and a control commune in Vietnam. SUBJECTS: Preschool children to 6 years of age living in the project commune Khai Xuan (average 469 children) and the control commune Ching Cong (average 251 children). MAIN OUTCOME MEASURES: Differences between the two communes over time in the incidence and severity of respiratory infections and the incidence of diarrhoeal disease. RESULTS: In Khai Xuan there was a significant reduction (P < 0.0001) in the incidence of respiratory infections (from 49.5% to 11.2%) and diarrhoeal infections (18.3% to 5.1%); the incidence of pneumonia and severe pneumonia was also significantly reduced (P < 0.0001). In Ching Cong there was no significant change in the incidence and severity of respiratory disease nor in the incidence of diarrhoeal disease. CONCLUSIONS: These findings emphasise the successful health outcome of a nutrition project based on household food production and nutrition education and the value of evaluating nutrition projects by reference to measurable health outcomes.     

Atypicalities in Perceptual Adaptation in Autism Do Not Extend to Perceptual Causality

A recent study showed that adaptation to causal events (collisions) in adults caused subsequent events to be less likely perceived as causal. In this study, we examined if a similar negative adaptation effect for perceptual causality occurs in children, both typically developing and with autism. Previous studies have reported diminished adaptation for face identity, facial configuration and gaze direction in children with autism. To test whether diminished adaptive coding extends beyond high-level social stimuli (such as faces) and could be a general property of autistic perception, we developed a child-friendly paradigm for adaptation of perceptual causality. We compared the performance of 22 children with autism with 22 typically developing children, individually matched on age and ability (IQ scores). We found significant and equally robust adaptation aftereffects for perceptual causality in both groups. There were also no differences between the two groups in their attention, as revealed by reaction times and accuracy in a change-detection task. These findings suggest that adaptation to perceptual causality in autism is largely similar to typical development and, further, that diminished adaptive coding might not be a general characteristic of autism at low levels of the perceptual hierarchy, constraining existing theories of adaptation in autism.     

Migraine increases centre-surround suppression for drifting visual stimuli

Background

The pathophysiology of migraine is incompletely understood, but evidence points to hyper-responsivity of cortical neurons being a key feature. The basis of hyper-responsiveness is not clear, with an excitability imbalance potentially arising from either reduced inhibition or increased excitation. In this study, we measure centre-surround contrast suppression in people with migraine as a perceptual analogue of the interplay between inhibition and excitation in cortical areas responsible for vision. We predicted that reduced inhibitory function in migraine would reduce perceptual surround suppression. Recent models of neuronal surround suppression incorporate excitatory feedback that drives surround inhibition. Consequently, an increase in excitation predicts an increase in perceptual surround suppression.

Methods and Findings

Twenty-six people with migraine and twenty approximately age- and gender-matched non-headache controls participated. The perceived contrast of a central sinusoidal grating patch (4 c/deg stationary grating, or 2 c/deg drifting at 2 deg/sec, 40% contrast) was measured in the presence and absence of a 95% contrast annular grating (same orientation, spatial frequency, and drift rate). For the static grating, similar surround suppression strength was present in control and migraine groups with the presence of the surround resulting in the central patch appearing to be 72% and 65% of its true contrast for control and migraine groups respectively (t(44) = 0.81, p = 0.42). For the drifting stimulus, the migraine group showed significantly increased surround suppression (t(44) = 2.86, p<0.01), with perceived contrast being on average 53% of actual contrast for the migraine group and 68% for non-headache controls.

Conclusions

In between migraines, when asymptomatic, visual surround suppression for drifting stimuli is greater in individuals with migraine than in controls. The data provides evidence for a behaviourally measurable imbalance in inhibitory and excitatory visual processes in migraine and is incompatible with a simple model of reduced cortical inhibitory function within the visual system.     

Genetic evidence for a distinct subtype of schizophrenia characterized by pervasive cognitive deficit

A novel phenotyping strategy in schizophrenia, targeting different neurocognitive domains, neurobehavioral features, and selected personality traits, has allowed us to identify a homogeneous familial subtype of the disease, characterized by pervasive neurocognitive deficit. Our genome scan data indicate that this subtype, which accounts for up to 50% of our sample, has a distinct genetic basis and explains linkage to chromosome 6p24 reported previously. If representative of other populations, the ratio of schizophrenia subtypes observed in our families could have a profound impact on sample heterogeneity and on the power of genetic studies to detect linkage and association. Our proposed abbreviated battery of tests should facilitate phenotype characterization for future genetic analyses and allow a focus on a crisply defined schizophrenia subtype, thus promoting a more informed search for susceptibility genes.     

Honeybee guards do not use food-derived odors to recognize non-nest mates: a test of the Odor Convergence hypothesis

Honeybee (Apis mellifera) colonies rob honey from each other during periods of nectar shortage. Persistent robbing can killweak colonies. Primarily responsible for preventing robbingare guard bees. Previous research has shown that the probabilityof both nest mate and non-nest mate workers being acceptedby guards at the nest entrance increases as nectar availability increases. The mechanism responsible for this change in guardacceptance can be explained by two competing hypotheses: OdorConvergence and Adaptive Threshold Shift. In this study wetested the Odor Convergence hypothesis. The acceptance by guardsat the nest entrance of workers transferred between four coloniesthat had been fed either odorless sucrose syrup (two colonies)or diluted heather honey (Calluna vulgaris) (two colonies)was measured for 3 days before feeding and during 2 weeks offeeding. Despite the large sample sizes, the probability ofguards accepting non-nest mates was not affected by the similaritiesor dissimilarities in food odor between guards' and non-nestmates' colonies. This finding contrasts with the accepted wisdom that food odors are important in nest mate recognition in honeybeesand the data, therefore, strongly reject the Odor Convergencehypothesis.     

Evidence for the assignment of Dolichopteryx brachyrhynchus Parr to the genus Bathylychnops Cohen (Pisces, Opisthoproctidae)

The rare opisthoproctid genus Bathylychnops has previously been regarded as containing a single species, B. exilis , known from the transition waters of the eastern North Pacific and, questionably, from the North Atlantic. While the post-larval and juvenile material reported here reaffirms the occurrence of the genus in the North Atlantic, and extends its range into the Indian Ocean, the lower vertebral and higher pelvic ray counts of specimens denies their reference to B. exilis. The systematics of the closely-related genus Dolichopteryx are poorly known, distinction from Bathylychnops resting mainly upon Dolichopteryx having multiserial, as opposed to uniserial, vomerine teeth and lacking an accessory scleral lens to the eye. The species D. brachyrhynchus , known from a single, damaged Atlantic specimen, shows marked similarities with Bathylychnops in pigmentation and the relative positions of fins, anus and dorsal adipose fin, thereby differing from all its congeners. Although the holotype of D. brachyrhynchus lacks an accessory scleral lens, perhaps through damage, it has uniserial vomerine teeth. This latter character and those of similarities in meristics, morphometrics and pigmentation shown with Atlantic-Indian Ocean Bathylychnops (contra B. exilis) are considered sufficient evidence to regard the two species as synonymous and hence transfer D. brachyrhynchus to the genus Bathylychnops.     

A new species of the deep-sea fish genus Cyclothone Goode & Bean (Stomiatoidei, Gonostomatidae) from the tropical Atlantic

A new gonostomatid species, Cyclothone parapallida , is described from the tropical Atlantic. Its affinities with C. pallida are shown by the shared characters especially the presence of an enlarged caniniform tooth in the premaxilla and a posterior, irregular series of minute teeth on the pterygoid, but it is distinguished from this species by its lower gill raker count [21-22 (23) v . 23–24 (22–25) first arch], its more restricted meningeal pigment, its lack of internasal pigment and its transparent dorsal and anal fin rays. Furthermore, it attains a larger maximum size, has a different geographic distribution pattern and, when sympatric, lives deeper than C. pallida . A synopsis of characters useful in distinguishing Cyclothone spp. in the Atlantic is presented.     

Micro-determination of clonazepam in plasma or serum by electron-capture gas—liquid chromatography

A rapid method is described for the electron-capture gas chromatographic determination of clonazepam in plasma or serum using methyl-clonazepam as an internal standard. The analysis is performed isothermally on the silicone stationary phase SP-2510DA (Supelco). With this liquid phase, gas chromatographic properties are comparable to methods involving acid hydrolysis or derivatisation. A short pre-column containing another phase is added to enhance resolution. The method involves a single extraction, requires 100 μl of sample and has a detection limit of 3 nmol/l. Response is linear at concentrations from 5–900 nmol/l and thus clonazepam analysis both during therapy and after overdosage is possible. Plasma and serum clonazepam levels are interchangeable.