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The disease caused by the influenza virus is a global public health problem due to its high rates of morbidity and mortality. Thus, analysis of the information generated by epidemiological surveillance systems has vital importance for health decision making. A retrospective analysis was performed using data generated by the four molecular diagnostic laboratories of the Mexican Social Security Institute between 2010 and 2016. Demographics, influenza positivity, seasonality, treatment choices and vaccination status analyses were performed for the vaccine according to its composition for each season. In all cases, both the different influenza subtypes and different age groups were considered separately. The circulation of A/H1N1pdm09 (48.7%), influenza A/H3N2 (21.1%), influenza B (12.6%), influenza A not subtyped (11%) and influenza A/H1N1 (6.6%) exhibited well-defined annual seasonality between November and March, and there were significant increases in the number of cases every 2 years. An inadequate use of oseltamivir was determined in 38% of cases, and the vaccination status in general varied between 12.1 and 18.5% depending on the season. Our results provide current information about influenza in Mexico and demonstrate the need to update both operational case definitions and medical practice guidelines to reduce the inappropriate use of antibiotics and antivirals.
The objective was to compare the performance of the updated Charlson comorbidity index (uCCI) and classical CCI (cCCI) in predicting 30-day mortality in patients with Staphylococcus aureus bacteraemia (SAB). All cases of SAB in patients aged ⩾14 years identified at the Microbiology Unit were included prospectively and followed. Comorbidity was evaluated using the cCCI and uCCI. Relevant variables associated with SAB-related mortality, along with cCCI or uCCI scores, were entered into multivariate logistic regression models. Global model fit, model calibration and predictive validity of each model were evaluated and compared. In total, 257 episodes of SAB in 239 patients were included (mean age 74 years; 65% were male). The mean cCCI and uCCI scores were 3.6 (standard deviation, 2.4) and 2.9 (2.3), respectively; 161 (63%) cases had cCCI score ⩾3 and 89 (35%) cases had uCCI score ⩾4. Sixty-five (25%) patients died within 30 days. The cCCI score was not related to mortality in any model, but uCCI score ⩾4 was an independent factor of 30-day mortality (odds ratio, 1.98; 95% confidence interval, 1.05–3.74). The uCCI is a more up-to-date, refined and parsimonious prognostic mortality score than the cCCI; it may thus serve better than the latter in the identification of patients with SAB with worse prognoses.
Understanding the peculiar properties of Ultra Diffuse Galaxies (UDGs) via spectroscopic analysis is a challenging task that is now becoming feasible. The advent of 10m-class telescopes and high sensitivity instruments is enabling the gathering of high quality spectra even for the faintest systems. In addition, advances in the modelling of stellar populations, stellar libraries, and full-spectral fitting codes are allowing the recovery of the stellar content shaping those spectra with unprecedented reliability. In this contribution we report on the extensive tests we have carried out using the inversion code STECKMAP. The similarities between the Star Formation Histories (SFH) recovered from STECKMAP (applied to high-quality spectra) and deep Colour-Magnitude diagrams fitting (resolved stars) in two Local Group dwarf galaxies (LMC and LeoA) are remarkable, demonstrating the impressive performance of STECKMAP. We exploit the capabilities of STECKMAP and perform one of the most complete and reliable characterisations of the stellar component of UDGs to date using deep spectroscopic data. We measure radial and rotation velocities, SFHs and mean population parameters, such as ages and metallicities, for a sample of five UDG candidates in the Coma cluster. From the radial velocities, we confirm the Coma membership of these galaxies. We find that their rotation properties, if detected at all, are compatible with dwarf-like galaxies. The SFHs of the UDG are dominated by old (∼ 7 Gyr), metal-poor ([M/H] ∼ -1.1) and alpha-enhanced ([Mg/Fe]∼ 0.4) populations followed by a smooth or episodic decline which halted ∼ 2 Gyr ago, possibly a sign of cluster-induced quenching. We find no obvious correlation between individual SFH shapes and any UDG morphological properties. The recovered stellar properties for UDGs are similar to those found for DDO 44, a local UDG analogue resolved into stars. We conclude that the UDGs in our sample are extended dwarfs whose properties are likely the outcome of both internal processes, such as bursty SFHs and/or high-spin haloes, as well as environmental effects within the Coma cluster.
TAOS II is a next-generation occultation survey with the goal of measuring the size distribution of the small end of the Kuiper Belt (objects with diameters 0.5–30 km). Such objects have magnitudes r > 30, and are thus undetectable by direct imaging. The project will operate three telescopes at San Pedro Mártir Observatory in Baja California, México. Each telescope will be equipped with a custom-built camera comprised of a focal-plane array of CMOS imagers. The cameras will be capable of reading out image data from 10,000 stars at a cadence of 20 Hz. The telescopes will monitor the same set of stars simultaneously to search for coincident occultation detections, thus minimising the false-positive rate. This talk described the project, and reported on the progress of the development of the survey infrastructure.
Genomic and genetic variation among six Italian chicken native breeds (Livornese, Mericanel della Brianza, Milanino, Bionda Piemontese, Bianca di Saluzzo and Siciliana) were studied using single nucleotide polymorphism (SNP) and copy number variants (CNV) as markers. A total of 94 DNA samples genotyped with Axiom® Genome-Wide Chicken Genotyping Array (Affymetrix) were used in the analyses. The results showed the genetic and genomic variability occurring among the six Italian chicken breeds. The genetic relationship among animals was established with a principal component analysis. The genetic diversity within breeds was calculated using heterozygosity values (expected and observed) and with Wright’s F-statistics. The individual-based CNV calling, based on log R ratio and B-allele frequency values, was done by the Hidden–Markov Model (HMM) of PennCNV software on autosomes. A hierarchical agglomerative clustering was applied in each population according to the absence or presence of definite CNV regions (CNV were grouped by overlapping of at least 1 bp). The CNV map was built on a total of 1003 CNV found in individual samples, after grouping by overlaps, resulting in 564 unique CNV regions (344 gains, 213 losses and 7 complex), for a total of 9.43 Mb of sequence and 1.03% of the chicken assembly autosome. All the approaches using SNP data showed that the Siciliana breed clearly differentiate from other populations, the Livornese breed separates into two distinct groups according to the feather colour (i.e. white and black) and the Bionda Piemontese and Bianca di Saluzzo breeds are closely related. The genetic variability found using SNP is comparable with that found by other authors in the same breeds using microsatellite markers. The CNV markers analysis clearly confirmed the SNP results.
Parasites can exert strong effects on population to ecosystem level processes, but data on parasites are limited for many global regions, especially tropical marine systems. Characterizing parasite diversity and distributions are the first steps towards understanding the potential impacts of parasites. The Panama Canal serves as an interesting location to examine tropical parasite diversity and distribution, as it is a conduit between two oceans and a hub for international trade. We examined metazoan and protistan parasites associated with ten oyster species collected from both Panamanian coasts, including the Panama Canal and Bocas del Toro. We found multiple metazoan taxa (pea crabs, Stylochus spp., Urastoma cyrinae). Our molecular screening for protistan parasites detected four species of Perkinsus (Perkinsus marinus, Perkinsus chesapeaki, Perkinsus olseni, Perkinsus beihaiensis) and several haplosporidians, including two genera (Minchinia, Haplosporidium). Species richness was higher for the protistan parasites than for the metazoans, with haplosporidian richness being higher than Perkinsus richness. Perkinsus species were the most frequently detected and most geographically widespread among parasite groups. Parasite richness and overlap differed between regions, locations and oyster hosts. These results have important implications for tropical parasite richness and the dispersal of parasites due to shipping associated with the Panama Canal.
Carbon nanotubes (CNTs) were synthesized by Chemical Vapor Deposition (CVD) from diethyl ether, butanol, hexane and ethyl acetate. A quartz tube with a stainless steel tube catalyst core with 0.019 m diameter and 0.6 m large formed the reactor. To avoid combustion, argon was used as the carrier gas. Time process ranged 30 to 60 min. The range of CNTs synthesis temperature was 680-850 °C for different precursors. Scanning Electron Microscopy micrographs have demonstrated tangled CNTs growth in all samples, thus presenting difficult length measurement. The CNTs diameters from diethyl ether are 45-200 nm, butanol diameter range from 55-230 nm, hexane diameter range is 50-130 nm and ethyl acetate range from 100 to 300 nm. Carbon content for all samples was higher than 93 %, CNTs from butanol showed carbon concentration up to 99%. FTIR, Raman and X-Ray Spectroscopies spectra for all samples demonstrated the characteristics signals present in carbon nanotubes. This research proposes a simple, effective and innovative method to synthesize CNTs by CVD on iron stainless steel catalyst in combination with diethyl ether, ethyl acetate, butanol and hexane as precursors by applying the principles of green chemistry, sustainability and its ease to be scaled.
The new detector MEPSICRON (microchannel electron position sensor with time resolution) is an image photomultiplier sensor for high spatial and time resolution, working in a photon counting regime. It has been especially designed for deep sky photometric pictures, for high resolution spectrophotometry with single or crossed dispersion spectrographs for long slit spectroscopic techniques, for high time resolution pictures and spectrophotometry especially related with speckles techniques and very fast varying sources as pulsars, and for Fabry-Pérot interferometry.
To analyze the factorial structure and psychometric properties of the Spanish adaptation of the AEQ, and to validate it by reporting relevant pain-related variables, which were not investigated in the original study. One hundred and fifty Spanish patients diagnosed with chronic back and neck pain were referred by physicians from different pain clinics in Spain; all the patients filled out the questionnaires at their clinic. A series of principal components analyses (PCA) was performed to develop the Spanish version of the AEQ. Reliability and validity were also calculated. The PCAs revealed five fear-avoidance scales (Kaiser-Meyer-Olkin measures were between .60 and .88, and Bartlett’s tests were significant, p < .01): the Depression scale (DS), Anxiety scale (AS), Catastrophizing scale (CS), Helplessness/hopelessness scale (HHS), and Avoidance of Social and Physical Activities scale (ASPAS), and three endurance-related responses scales: Pain Persistence Behaviour and Distraction scale (PPDS), Ignoring Pain scale (IPS), and Humor scale (HS). All the scales showed high internal consistency (α > .73) and suitable validity (p < .05). New results associated with pain-related cognitive/affective and behavioural responses are discussed. This instrument will probably help clinicians to identify Spanish patients at a high risk of chronicity and to develop treatments tailored to the different profiles in order to improve secondary and tertiary prevention in back and neck pain.
The current ideas concerning the evolution of close binary systems (van den Heuvel, 1976), accepting the hypothesis that the system is not disrupted by the first supernova (SN) explosion, predict that the Wolf-Rayet phase can occur twice. The first time the companion of the WR star is a normal OB star and the second time it is a collapsed object. In this context, the importance of searching for binary systems with collapsed companions among the “single” WR stars is evident. Due to its large distance from the galactic plane, z = 280 pc (Smith, 1968a), when compared with the average height (z = 60 pc, Cruz-González et al., 1974) of extreme Population I stars, HD 50896 was considered to be a likely candidate to this type of system.
Acute respiratory infections remain the principal cause of morbidity and mortality in Moroccan children. Besides bacterial infections, respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) are prominent among other viruses due to their high prevalence and association with severe clinical episodes. We aimed to describe and compare RSV- and hMPV-associated cases of WHO-defined severe pneumonia in a paediatric population admitted to Morocco's reference hospital. Children aged 2–59 months admitted to the Hôpital d'Enfants de Rabat, Morocco meeting WHO-defined severe pneumonia criteria were recruited during 14 months and thoroughly investigated to ascertain a definitive diagnosis. Viral prevalence of RSV, hMPV and other viruses causing respiratory symptoms was investigated in nasopharyngeal aspirate samples through the use of molecular methods. Of the 683 children recruited and included in the final analysis, 61/683 (8·9%) and 124/683 (18·2%) were infected with hMPV and RSV, respectively. Besides a borderline significant tendency for higher age in hMPV cases, patients infected with either of the viruses behaved similarly in terms of demographics, patient history, past morbidity and comorbidity, vaccination history, socioeconomic background and family environment. Clinical presentation on arrival was also similar for both viruses, but hMPV cases were associated with more severity than RSV cases, had a higher risk of intensive care need, and received antibiotic treatment more frequently. RSV and hMPV are common and potentially life-threatening causes of WHO-defined pneumonia in Moroccan children. Both viruses show indistinctive clinical symptomatology, but in Moroccan children, hMPV was associated with a more severe evolution.
To determine whether controlling the prescription of targeted antibiotics would translate to a measurable reduction in hospital-onset Clostridium difficile infection (CDI) rates.
A multicenter before-and-after intervention comparative study.
Ten medical centers in the greater New York region. Intervention group comprised of 6 facilities with early antimicrobial stewardship programs (ASPs). The 4 facilities without ASPs made up the nonintervention group.
Intervention facilities identified target antibiotics using case-control studies and implemented ASP-based strategies to control their use. Pre- and postintervention hospital-onset CDI rates and antibiotic consumption were compared for a 20-month period from June 2010 to January 2012. Antibiotic usage was compared using defined daily dose, days of therapy, and number of courses prescribed. Comparisons used bivariate and regression techniques.
Intervention facilities identified piperacillin/tazobactam, fluoroquinolones, or cefepime (odds ratio, 2.0-9.8 in CDI case patients compared with those without CDI) as intervention targets and selected several interventions (all included a component of audit and feedback). Varying degrees of success were observed in reducing antibiotic consumption over time. Total target antibiotic use significantly decreased (P < .05) when measured by days of therapy and number of courses but not by defined daily dose. Intravenous moxifloxacin and oral ciprofloxacin use showed significant reduction when measured by defined daily dose and days of therapy (P ≤ .01). Number of courses with all forms of these antibiotics was reduced (P ≤ .005). Intervention hospitals reported fewer hospital-onset CDI cases (2.8 rate point difference) compared with nonintervention hospitals; however, we were unable to show statistically significant decreases in aggregate hospital-onset CDI either between intervention and nonintervention groups or within the intervention group over time.
Although decreases in target antibiotic consumption did not translate into reductions of hospital-onset CDI in this study, many valuable lessons (including implementation strategies and antibiotic consumption measures) were learned. The findings can inform potential policy decisions regarding incorporating control of CDI and ASP as healthcare quality measures.
The organogenesis of the digestive system was described in the Amazonian pimelodid catfish species Pseudoplatystoma punctifer from hatching (3.5 mm total length, TL) to 41 days post-fertilization (dpf) (58.1 mm TL) reared at 28°C. Newly hatched larvae showed a simple digestive tract, which appeared as a straight undifferentiated and unfolded tube lined by a single layer of columnar epithelial cells (future enterocytes). During the endogenous feeding period, comprised between 20 and 96 h post-fertilization (3.5 to 6.1 mm TL), the larval digestive system experienced a fast transformation with the almost complete development and differentiation of most of digestive organs (buccopahrynx, oesophagus, intestine, liver and exocrine pancreas). Yolk reserves were not completely depleted at the onset of exogenous feeding (4 dpf, 6.1 mm TL), and a period of mixed nutrition was observed up to 6 to 7 dpf (6.8 to 7.3 mm TL) when yolk was definitively exhausted. The stomach was the organ that latest achieved its complete differentiation, characterized by the development of abundant gastric glands in the fundic stomach between 10 and 15 dpf (10.9 to 15.8 mm TL) and the formation of the pyloric sphincter at the junction of the pyloric stomach and the anterior intestine at 15 dpf (15.8 mm TL). The above-mentioned morphological and histological features observed suggested the achievement of a digestive system characteristic of P. punctifer juveniles and adults. The ontogeny of the digestive system in P. punctifer followed the same general pattern as in most Siluriform species so far, although some species-specific differences in the timing of differentiation of several digestive structures were noted, which might be related to different reproductive guilds, egg and larval size or even different larval rearing practices. According to present findings on the histological development of the digestive system in P. punctifer, some recommendations regarding the rearing practices of this species are also provided in order to improve the actual larval rearing techniques of this fast-growing Neotropical catfish species.
Two in vitro experiments were conducted to analyse the effects of replacing dietary barley grain with wastes of tomato and cucumber fruits and a 1 : 1 tomato : cucumber mixture on rumen fermentation characteristics and microbial abundance. The control (CON) substrate contained 250 g/kg of barley grain on a dry matter (DM) basis, and another 15 substrates were formulated by replacing 50, 100, 150, 200 or 250 g of barley grain/kg with the same amount (DM basis) of tomato or cucumber fruits or 1 : 1 tomato : cucumber mixture. In Expt 1, all substrates were incubated in batch cultures with rumen micro-organisms from goats for 24 h. Increasing amounts of tomato, cucumber and the mixture of both fruits in the substrate increased final pH and gas production, without changes in final ammonia-nitrogen (NH3-N) concentrations, substrate degradability and total volatile fatty acid (VFA) production, indicating that there were no detrimental effects of any waste fruits on rumen fermentation. Therefore, in Expt 2 the substrates including 250 g of waste fruits (T250, C250 and M250 for tomato, cucumber and the mixture of both fruits, respectively) and the CON substrate were incubated in single-flow continuous-culture fermenters for 8 days. Total VFA production did not differ among substrates, but there were differences in VFA profile. Molar proportions of propionate, isobutyrate and isovalerate were lower and acetate : propionate ratio was greater for T250 compared with CON substrate. Fermentation of substrates containing cucumber (C250 and M250) resulted in lower proportions of acetate, isobutyrate and isovalerate and acetate : propionate ratio, but greater butyrate proportions than the CON substrate. Carbohydrate degradability and microbial N synthesis tended to be lower for substrates containing cucumber than for the CON substrate, but there were no differences between CON and T250 substrates. Abundance of total bacteria, Fibrobacter succinogenes and Ruminococcus flavefaciens, fungi, methanogenic archaea and protozoa were similar in fermenters fed T250 and CON substrates, but fermenters fed C250 and M250 substrates had lower abundances of R. flavefaciens, fungi and protozoa than those fed the CON substrate. Results indicated that tomato fruits could replace dietary barley grain up to 250 g/kg of substrate DM without noticeable effects on rumen fermentation and microbial populations, but the inclusion of cucumber fruits at 250 g/kg of substrate DM negatively affected some microbial populations as it tended to reduce microbial N synthesis and changed the VFA profile. More studies are needed to identify the dietary inclusion level of cucumber which produces no detrimental effects on rumen fermentation and microbial growth.
In vitro and in vivo experiments were designed to evaluate the effectiveness of laboratory-made di-d-fructose dianhydride (DFA)-enriched caramels. The DFA-enriched caramels were obtained from d-fructose (FC), d-fructose and sucrose (FSC), or d-fructose and β-cyclodextrin (FCDC). In the in vitro experiment, raftilose and all caramels increased (P<0.05) l-lactate concentration and decreased (P<0.05) pH. Total short-chain fatty acid concentration was higher (P<0.05) than controls in tubes containing raftilose, FSC, FCDC and commercial sucrose caramel (CSC). Raftilose, and all caramels tested except FSC and FC (1%), increased (P<0.01) lactobacilli log10 number of copies compared with the non-additive control. FSC, FCDC and CSC increased (P<0.01) the bifidobacteria number of copies as compared with controls. All additives, except FCDC, decreased (P<0.01) Clostridium coccoides/Eubacterium rectale log number of copies. Compared with controls, raftilose, FC and CSC led to lower (P<0.01) Escherichia–Shigella and enterobacteria. For the in vivo experiment, a total of 144 male 1-day-old broiler chickens of the Cobb strain were randomly assigned to one of the three dietary treatments for 21 days. Dietary treatments were control (commercial diet with no additive), inulin (20 g inulin/kg diet) and FC (20 g FC/kg diet). Final BW of birds fed FC diet was higher (P<0.01) than controls or inulin-fed birds, although feed: gain values were not different. Feed intake of chickens fed FC was higher (P<0.01) than that of inulin-fed birds but not statistically different from controls. Crop pH values were lower (P<0.01) in birds fed FC diet as compared with control diet, with inulin-fed chickens showing values not different from control- or FC-fed birds. Lower (P<0.05) lactobacilli number of copies was determined in the crop, ileum and caeca of birds fed the inulin diet compared with the control diet. Inulin supplementation also resulted in lower (P<0.05) C. coccoides/E. rectale, bacteroides and total bacteria in caecal contents. Addition of FC to broiler diets gave place to lower (P<0.05) enterobacteria and Escherichia–Shigella in crop and caecal contents compared with controls. The bacteroides number of copies increased (P<0.05) as compared with controls in the ileum, but decreased (P<0.05) in the caeca of chickens fed the FC diet. Energy, ADF, NDF and non-starch polysaccharides faecal digestibilities were greater (P<0.05) than controls in chickens fed diets containing inulin or FC. Fat digestibility was higher (P<0.05) in FC-fed birds compared with controls or inulin-fed chickens. In conclusion, DFA-enriched caramels tested here, particularly FC, may represent a type of new additives useful in poultry production.