Environmental variables associated with an increased risk of invasive aspergillosis

Information on the environmental variables that may affect the incidence of invasive aspergillosis (IA) is scarce. We sought to determine the relationship between airborne spore counts, climatic conditions and IA. We also examined whether circulating respiratory viruses predispose patients to IA in a multicentre cohort study of hospitalized adults with IA. Data on environmental mould spores, climatic conditions and circulating respiratory viruses were obtained from the Environmental Department of the Autonomous University of Barcelona, the Meteorological Service of Catalonia and the Acute Respiratory Infection Surveillance Project in Catalonia, respectively. Between 2008 and 2011, 165 patients with IA were identified. Diagnosis was based on one or more of the following: culture (125 cases), galactomannan antigen (98) and histology (34). One hundred and twenty-seven cases (77%) had criteria for probable IA and the remainder for proven IA. Environmental mould spore counts from the period 28–42 days preceding infection presented significant associations with admissions due to IA. None of the climatic conditions were associated with an increased risk of IA, but the presence of circulating respiratory viruses was associated with a higher risk of infection: the most strongly associated viruses were respiratory syncytial virus, influenza A(H1N1)pdm09 and adenovirus. In conclusion, the presence of high numbers of spores in the air increases the risk of admission due to IA. Circulating respiratory viruses appear to be associated with a higher risk of developing IA. Physicians should be aware of this association in order to optimize prevention and diagnosis strategies for IA during viral epidemic periods.     

Measuring socioeconomic health inequalities in presence of multiple categorical information

While many of the measurement approaches in health inequality measurement assume the existence of a ratio-scale variable, most of the health information available in population surveys is given in the form of categorical variables. Therefore, the well-known inequality indices may not always be readily applicable to measure health inequality as it may result in the arbitrariness of the health concentration index's value. In this paper, we address this problem by changing the dimension in which the categorical information is used. We therefore exploit the multi-dimensionality of this information, define a new ratio-scale health status variable and develop positional stochastic dominance conditions that can be implemented in a context of categorical variables. We also propose a parametric class of population health and socioeconomic health inequality indices. Finally we provide a twofold empirical illustration using the Joint Canada/United States Surveys of Health 2004 and the National Health Interview Survey 2010.     

Sex-specific endothelial dysfunction induced by high-cholesterol diet in rats: The role of protein tyrosine kinase and nitric oxide

Background and aimsAtherosclerosis is a chronic process playing a crucial role in the pathogenesis of cardiovascular disease. Sex-specific differences in the incidence of atherosclerosis indicate that estrogen has a protective effect on the cardiovascular disease. However, the role of sex on endothelium responses in animal models of high cholesterol (HC) diet-induced atherosclerosis has not been fully investigated. This study was aimed to investigate vascular responses in HC-fed rats.Methods and resultsMale and female Sprague rats (12-week-old) were treated with either a standard diet (n = 12 of each sex) or an HC enriched diet (n = 12 of each sex) containing 2% cholesterol for 24 weeks. HC treated animals (both sexes) showed increased levels of total cholesterol, LDL-cholesterol, triglyceride and blood pressure (BP) compared to control rats. While the BP of control rats (both sexes) was increased following aminoguanidine administration (AG, 100 mg/kg i.p.), it was not changed in HC animals (both sexes). The hypotensive effect of acetylcholine was significantly impaired in male HC-treated rats. In vitro experiments demonstrated that aortic rings from HC group (both sexes) had an increased contractile response to phenylephrine and a decreased vasodilatory response to acetylcholine. The vasorelaxant effect of acetylcholine in HC rats (only male) was improved by applying 10^?5 M genistein (tyrosine kinase inhibitor) or AG.ConclusionHC diet alters endothelium function through Nitric oxide (NO) and tyrosine kinase pathways in male rats.     

Molecular characterization of genome segment 2 encoding RNA dependent RNA polymerase of Antheraea mylitta cytoplasmic polyhedrosis virus

Genome segment 2 (S2) from Antheraea mylitta cypovirus (AmCPV) was converted into cDNA, cloned and sequenced. S2 consisted of 3798 nucleotides with a long ORF encoding a 1116 amino acid long protein (123 kDa). BLAST and phylogenetic analysis showed 29% sequence identity and close relatedness of AmCPV S2 with RNA dependent RNA polymerase (RdRp) of other insect cypoviruses, suggesting a common origin of all insect cypoviruses. The ORF of S2 was expressed as 123 kDa soluble His-tagged fusion protein in insect cells via baculovirus recombinants which exhibited RdRp activity in an in vitro RNA polymerase assay without any intrinsic terminal transferase activity. Maximum activity was observed at 37 °C at pH 6.0 in the presence of 3 mM MgCl_2. Site directed mutagenesis confirmed the importance of the conserved GDD motif. This is the first report of functional characterization of a cypoviral RdRp which may lead to the development of anti-viral agents.     

Adolescent brain maturation,the endogenous cannabinoid system and the neurobiology of cannabis-induced schizophrenia

Cannabis use during adolescence increases the risk of developing psychotic disorders later in life. However, the neurobiological processes underlying this relationship are unknown. This review reports the results of a literature search comprising various neurobiological disciplines, ultimately converging into a model that might explain the neurobiology of cannabis-induced schizophrenia. The article briefly reviews current insights into brain development during adolescence. In particular, the role of the excitatory neurotransmitter glutamate in experience-dependent maturation of specific cortical circuitries is examined. The review also covers recent hypotheses regarding disturbances in strengthening and pruning of synaptic connections in the prefrontal cortex, and the link with latent psychotic disorders. In the present model, cannabis-induced schizophrenia is considered to be a distortion of normal late postnatal brain maturation. Distortion of glutamatergic transmission during critical periods may disturb prefrontal neurocircuitry in specific brain areas. Our model postulates that adolescent exposure to Δ9-tetrahydrocannabinol (THC), the primary psychoactive substance in cannabis, transiently disturbs physiological control of the endogenous cannabinoid system over glutamate and GABA release. As a result, THC may adversely affect adolescent experience-dependent maturation of neural circuitries within prefrontal cortical areas. Depending on dose, exact time window and duration of exposure, this may ultimately lead to the development of psychosis or schizophrenia. The proposed model provides testable hypotheses which can be addressed in future studies, including animal experiments, reanalysis of existing epidemiological data, and prospective epidemiological studies in which the role of the dose–time–effect relationship should be central.     

Adaptive training of cortical feature maps for a robot sensorimotor controller

This work investigates self-organising cortical feature maps (SOFMs) based upon the Kohonen Self-Organising Map (SOM) but implemented with spiking neural networks. In future work, the feature maps are intended as the basis for a sensorimotor controller for an autonomous humanoid robot. Traditional SOM methods require some modifications to be useful for autonomous robotic applications. Ideally the map training process should be self-regulating and not require predefined training files or the usual SOM parameter reduction schedules. It would also be desirable if the organised map had some flexibility to accommodate new information whilst preserving previous learnt patterns. Here methods are described which have been used to develop a cortical motor map training system which goes some way towards addressing these issues. The work is presented under the general term ‘Adaptive Plasticity’ and the main contribution is the development of a ‘plasticity resource’ (PR) which is modelled as a global parameter which expresses the rate of map development and is related directly to learning on the afferent (input) connections. The PR is used to control map training in place of a traditional learning rate parameter. In conjunction with the PR, random generation of inputs from a set of exemplar patterns is used rather than predefined datasets and enables maps to be trained without deciding in advance how much data is required. An added benefit of the PR is that, unlike a traditional learning rate, it can increase as well as decrease in response to the demands of the input and so allows the map to accommodate new information when the inputs are changed during training.     

Variables Associated With Breastfeeding Duration

Objective: To identify the variables associated with breastfeeding duration.
Data Sources: The health science reference databases of CINAHL, PubMed, and the Cochrane Database of Systematic Reviews.
Study Selection: Meta-analyses, Cochrane reviews, literature reviews, and quantitative and qualitative studies published in English from 1998 through 2008.
Data Extraction: Data included all variables, both positive and negative, that were found to influence the outcome of breastfeeding duration.
Data Synthesis: Demographic factors that influence breastfeeding duration are race, age, marital status, education, socioeconomics, and Special Supplemental Nutrition Program for Women, Infants, and Children status. Biological variables consisted of insufficient milk supply, infant health problems, maternal obesity, and the physical challenges of breastfeeding, maternal smoking, parity, and method of delivery. Social variables included paid work, family support, and professional support. Maternal intention, interest, and confidence in breastfeeding were psychological variables.
Conclusion: Human lactation is a complex phenomena and the duration of breastfeeding is influenced by many demographic, physical, social, and psychological variables.