18 research outputs found
Environmental methods for dengue vector control - A systematic review and meta-analysis
Background Vector control remains the primary method to prevent dengue infections. Environmental interventions represent sustainable and safe methods as there are limited risks of environmental contamination and toxicity. The objective of this study is to perform a systematic review and meta-analysis of the effectiveness of the following environmental methods for dengue vector control. Methodology/Principal findings Following the PRISMA guidelines, a systematic literature search was conducted using the databases PubMed, EMBASE, LILACS, the Cochrane Library and Google Scholar. Quality assessment was done using the CONSORT 2010 checklist. For the meta-analysis the difference-in-differences (DID) and the difference-of-endlines (DOE) were calculated according to the Schmidt-Hunter method for the Breteau index (BI) and the pupae per person index (PPI). Nineteen studies were eligible for the systematic review, sixteen contributed data to the meta-analysis. The following methods were evaluated: (a) container covers with and without insecticides, (b) waste management and clean-up campaigns, and (c) elimination of breeding sites by rendering potential mosquito breeding sites unusable or by eliminating them. Study quality was highest for container covers with insecticides, followed by waste management without direct garbage collection and elimination of breeding places. Both, systematic review and meta-analysis, showed a weak effect of the interventions on larval populations, with no obvious differences between the results of each individual method. For the meta-analysis, both, container covers without insecticides (BI: DID -7.9, DOE -5) and waste management with direct garbage collection (BI: DID -8.83, DOE -6.2) achieved the strongest reductions for the BI, whereas for the PPI results were almost opposite, with container covers with insecticides (PPI: DID -0.83, DOE 0.09) and elimination of breeding places (PPI: DID -0.95, DOE -0.83) showing the strongest effects. Conclusions Each of the investigated environmental methods showed some effectiveness in reducing larval and pupal densities of Aedes sp. mosquitoes. However, there is a need for more comparable high-quality studies at an adequate standard to strengthen this evidence. Author summary Dengue is an emerging mosquito-borne viral disease, which is transmitted through the bite of Aedes sp. mosquitoes. The dengue virus causes 390 million infections and 96 million cases every year, and represents a major public health problem in the tropics and subtropics. Although a dengue vaccine was licensed in late 2015, it does not represent a general solution due to significant imperfections. Vector control remains still the primary method to prevent dengue infections. Environmental interventions to control dengue vectors represent sustainable and safe methods as there are limited risks of environmental contamination and toxicity. We provide a systematic review and meta-analysis of the effectiveness of the following environmental methods for dengue vector control: container covers with and without insecticides, waste management with and without direct garbage collection, elimination of breeding places. Both, systematic review and meta-analysis, showed a weak effect of the interventions on larval Aedes sp. populations, with no obvious differences between the results of each individual method. However, there is a need for more comparable high-quality studies at an adequate standard to strengthen this evidence
Observing CMB polarisation through ice
Ice crystal clouds in the upper troposphere can generate polarisation signals
at the uK level. This signal can seriously affect very sensitive ground based
searches for E- and B-mode of Cosmic Microwave Background polarisation. In this
paper we estimate this effect within the ClOVER experiment observing bands (97,
150 and 220 GHz) for the selected observing site (Llano de Chajnantor, Atacama
desert, Chile). The results show that the polarisation signal from the clouds
can be of the order of or even bigger than the CMB expected polarisation.
Climatological data suggest that this signal is fairly constant over the whole
year in Antarctica. On the other hand the stronger seasonal variability in
Atacama allows for a 50% of clean observations during the dry season.Comment: 7 Pages, 4 figure
Protein Rates of Evolution Are Predicted by Double-Strand Break Events, Independent of Crossing-over Rates
Theory predicts that, owing to reduced Hill–Robertson interference, genomic regions with high crossing-over rates should experience more efficient selection. In Saccharomyces cerevisiae a negative correlation between the local recombination rate, assayed as meiotic double-strand breaks (DSBs), and the local rate of protein evolution has been considered consistent with such a model. Although DSBs are a prerequisite for crossing-over, they need not result in crossing-over. With recent high-resolution crossover data, we now return to this issue comparing two species of yeast. Strikingly, even allowing for crossover rates, both the rate of premeiotic DSBs and of noncrossover recombination events predict a gene's rate of evolution. This both questions the validity of prior analyses and strongly suggests that any correlation between crossover rates and rates of protein evolution could be owing to slow-evolving genes being prone to DSBs or a direct effect of DSBs on sequence evolution. To ask if classical theory of recombination has any relevance, we determine whether crossover rates predict rates of protein evolution, controlling for noncrossover DSB events, gene ontology (GO) class, gene expression, protein abundance, nucleotide content, and dispensability. We find that genes with high crossing-over rates have low rates of protein evolution after such control, although any correlation is weaker than that previously reported considering meiotic DSBs as a proxy. The data are consistent both with recombination enhancing the efficiency of purifying selection and, independently, with DSBs being associated with low rates of evolution
Khat use as risk factor for psychotic disorders: A cross-sectional and case-control study in Somalia
BACKGROUND: Little is known about the prevalence of khat-induced psychotic disorders in East African countries, where the chewing of khat leaves is common. Its main psycho-active component cathinone produces effects similar to those of amphetamine. We aimed to explore the prevalence of psychotic disorders among the general population and the association between khat use and psychotic symptoms. METHODS: In an epidemiological household assessment in the city of Hargeisa, North-West Somalia, trained local interviewers screened 4,854 randomly selected persons from among the general population for disability due to severe mental problems. The identified cases were interviewed based on a structured interview and compared to healthy matched controls. Psychotic symptoms were assessed using the items of the WHO Composite International Diagnostic Interview and quantified with the Positive and Negative Symptoms Scale. Statistical testing included Student's t-test and ANOVA. RESULTS: Local interviewers found that rates of severe disability due to mental disorders were 8.4% among males (above the age of 12) and differed according to war experiences (no war experience: 3.2%; civilian war survivors: 8.0%; ex-combatants: 15.9%). The clinical interview verified that in 83% of positive screening cases psychotic symptoms were the most prominent manifestations of psychiatric illness. On average, cases with psychotic symptoms had started to use khat earlier in life than matched controls and had been using khat 8.6 years before positive symptoms emerged. In most cases with psychotic symptoms, a pattern of binge use (> two 'bundles' per day) preceded the onset of psychotic symptoms, in contrast to controls of the same age. We found significant correlations between variables of khat consumption and clinical scales (0.35 to 0.50; p < 0.05), and between the age of onset of khat chewing and symptom onset (0.70; p <0.001). CONCLUSION: Evidence indicates a relationship between the consumption of khat and the onset of psychotic symptoms among the male population, whereby not the khat intake per se but rather early onset and excessive khat chewing seemed to be related to psychotic symptoms. The khat problem must be addressed by means other than prohibition, given the widespread use and its role in Somali culture
Ribonucleoprotein Assembly Defects Correlate with Spinal Muscular Atrophy Severity and Preferentially Affect a Subset of Spliceosomal snRNPs
Spinal muscular atrophy (SMA) is a motor neuron disease caused by reduced levels of the survival motor neuron (SMN) protein. SMN together with Gemins2-8 and unrip proteins form a macromolecular complex that functions in the assembly of small nuclear ribonucleoproteins (snRNPs) of both the major and the minor splicing pathways. It is not known whether the levels of spliceosomal snRNPs are decreased in SMA. Here we analyzed the consequence of SMN deficiency on snRNP metabolism in the spinal cord of mouse models of SMA with differing phenotypic severities. We demonstrate that the expression of a subset of Gemin proteins and snRNP assembly activity are dramatically reduced in the spinal cord of severe SMA mice. Comparative analysis of different tissues highlights a similar decrease in SMN levels and a strong impairment of snRNP assembly in tissues of severe SMA mice, although the defect appears smaller in kidney than in neural tissue. We further show that the extent of reduction in both Gemin proteins expression and snRNP assembly activity in the spinal cord of SMA mice correlates with disease severity. Remarkably, defective SMN complex function in snRNP assembly causes a significant decrease in the levels of a subset of snRNPs and preferentially affects the accumulation of U11 snRNP—a component of the minor spliceosome—in tissues of severe SMA mice. Thus, impairment of a ubiquitous function of SMN changes the snRNP profile of SMA tissues by unevenly altering the normal proportion of endogenous snRNPs. These findings are consistent with the hypothesis that SMN deficiency affects the splicing machinery and in particular the minor splicing pathway of a rare class of introns in SMA
Controlled Ovarian Stimulation with recombinant-FSH plus recombinant-LH vs. human Menopausal Gonadotropin based on the number of retrieved oocytes: results from a routine clinical practice in a real-life population
Occurrence of non-proteolytic amino acyl derivatives in dry-cured ham
Proteolysis is the most important event occurring during maturation of dry-cured hams: it strongly influences the flavour and the texture of the aged ham by the accumulation of peptides and free amino acids released by protein hydrolysis. Apart from compounds of proteolytic origin, it has been demonstrated that also non-proteolytic amino acyl derivatives (Îł-glutamyl amino acids, pyroglutamyl-amino acids and lactoyl-amino acids) may accumulate during ripening of cheese, and they can be also found in fermented soy sauce, where they contribute to the umami taste of the products. Using a semi-quantitative analysis, in this paper we report the occurrence of significant amounts of Îł-glutamyl amino acids and, for the first time, pyroglutamyl-amino acids and lactoyl-amino acids, in aged ham. The amino acid counterparts were mainly found to be hydrophobic amino acids. The amount of these compounds was found to increase with time, because they are not degraded by proteolytic activity. They were also found to be stable to simulated gastrointestinal digestion. Angiotensin Converting Enzyme inhibitory activity was also tested, but they were not found to be characterized by significant ACE-inhibitory activity