Recent studies found that isolates of
Toxoplasma gondii from Brazil were biologically and genetically different from those in North America and Europe. However, to date only a small number of ...isolates have been analysed from different animal hosts in Brazil. In the present study DNA samples of 46
T. gondii isolates from cats in 11 counties in São Paulo state, Brazil were genetically characterised using 10 PCR restriction fragment length polymorphism markers including
SAG1,
SAG2,
SAG3,
BTUB,
GRA6, c22-8, c29-2, L358,
PK1 and Apico. An additional marker, CS3, that locates on chromosome VIIa and has previously been shown to be linked to acute virulence of
T. gondii was also used to determine its association to virulence in mice. Genotyping of these 46 isolates revealed a high genetic diversity with 20 genotypes but no clonal Type I, II or III lineage was found. Two of the 46 isolates showed mixed infections. Combining genotyping data in this study with recent reported results from chickens, dogs and cats in Brazil (total 125 isolates) identified 48 genotypes and 26 of these genotypes had single isolates. Four of the 48 genotypes with multiple isolates identified from different hosts and locations are considered the common clonal lineages in Brazil. These lineages are designated as Types BrI, BrII, BrIII and BrIV. These results indicate that the
T. gondii population in Brazil is highly diverse with a few successful clonal lineages expanded into wide geographical areas. In contrast to North America and Europe, where the Type II clonal lineage is overwhelmingly predominant, no Type II strain was identified from the 125 Brazil isolates. Analysis of mortality rates in infected mice indicates that Type BrI is highly virulent, Type BrIII is non-virulent, whilst Type BrII and BrIV lineages are intermediately virulent. In addition, allele types at the CS3 locus are strongly linked to mouse-virulence of the parasite. Thus,
T. gondii has an epidemic population structure in Brazil and the major lineages have different biological traits.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Coherent x-ray diffractive imaging is a powerful method for studies on nonperiodic structures on the nanoscale. Access to femtosecond dynamics in major physical, chemical, and biological processes ...requires single-shot diffraction data. Up to now, this has been limited to intense coherent pulses from a free electron laser. Here we show that laser-driven ultrashort x-ray sources offer a comparatively inexpensive alternative. We present measurements of single-shot diffraction patterns from isolated nano-objects with a single 20 fs pulse from a table-top high-harmonic x-ray laser. Images were reconstructed with a resolution of 119 nm from the single shot and 62 nm from multiple shots.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Toxoplasma gondii infections are common in humans and animals worldwide. Domestic free-range chickens (Gallus domesticus) are excellent sentinels of environmental contamination with T. gondii oocysts ...because they feed on the ground. Chickens can be easily infected with T. gondii; however, clinical toxoplasmosis is rare in these hosts. Chickens are comparatively inexpensive and thus are good sentinel animals for T. gondii infections on the farms. Here, the authors reviewed prevalence, the persistence of infection, clinical disease, epidemiology and genetic diversity of T. gondii strains isolated from chickens worldwide for the past decade. Data on phenotypic and molecular characteristics of 794 viable T. gondii strains from chickens are discussed, including new data on T. gondii isolates from chickens in Brazil. This paper will be of interest to biologists, epidemiologists, veterinarians and parasitologists.
The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known ...archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by pre-Columbian peoples. Domesticated species are five times more likely than nondomesticated species to be hyperdominant. Across the basin, the relative abundance and richness of domesticated species increase in forests on and around archaeological sites. In southwestern and eastern Amazonia, distance to archaeological sites strongly influences the relative abundance and richness of domesticated species. Our analyses indicate that modern tree communities in Amazonia are structured to an important extent by a long history of plant domestication by Amazonian peoples.
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BFBNIB, NMLJ, NUK, ODKLJ, PNG, SAZU, UL, UM, UPUK
We study materials that present challenges for conventional elemental mapping techniques and can in some cases be treated successfully using independent component analysis (ICA). In this case the ...material in question is obtained from a TiO
2–SiO
2 solid solution that is spinodally decomposed into TiO
2 rich–SnO
2 rich multilayers. Conventional elemental mapping is difficult because the edges most easily mapped for these elements (Ti-L, Sn-M and O-K) all have onsets within the same 80
eV range. ICA is used to separate entire spectral signals corresponding to particular material phases or molecular units rather than particular elements and is thus able to distinguish between TiO
2 and SnO
2. We show that quantification of oxide species can be performed by different methods that require extra assumptions, but nevertheless should be feasible in many cases.
► EELS quantification for elements with superposed edges is very difficult. ► ICA provides an alternative approach in some cases, and here for Ti and Sn oxides. ► Quantification is consistent with measured HAADF imaging intensities. ► The method is an extension of and variant on the more widely used PCA.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
There are few prospective studies with sufficient duration in time to evaluate clinical and antibiotic resistance impact of antibiotic stewardship programs (ASP). This is a descriptive study between ...January 2012 and December 2017, pre-post intervention. A meropenem ASP was initiated in January 2015; in patients who started treatment with meropenem, an infectious disease physician performed treatment recommendations to prescribers. Prospective information was collected to evaluate adequacy of meropenem prescription to local guidelines and to compare results between cases with accepted or rejected intervention. Analysis was performed to verify variables associated with intervention acceptance and with any significant change in meropenem consumption, hospital-acquired multidrug-resistant (MDR) bloodstream infections (BSIs), and 30-day all-cause crude death in MDR BSIs. Adequacy of meropenem prescription and de-escalation from meropenem treatment to narrower-spectrum antibiotic improved progressively over time, after ASP implementation (
p
< 0.001). Interventions on prescription were performed in 330 (38.7%) patients without meropenem justified treatment; in 269, intervention was accepted and in 61 not. Intervention acceptance was associated with shorter duration of treatment, cost, and inpatient days (
p
< 0.05); intervention rejection was not associated with severity of patient. During the period 2015–2017, meropenem consumption decreased compared with 2012–2014 (rate ratio RR 0.67; 95% CI 0.58–0.77,
p
< 0.001). Also decreased were hospital-acquired MDR BSI rate (RR 0.63; 95% CI 0.38–1.02,
p
= 0,048) and 30-day all-cause crude death in MDR BSIs (RR 0.45; 95% CI 0.14–1.24,
p
= 0.096), coinciding in time with ASP start-up. The decrease and better use of meropenem achieved had a sustained clinical, economic, and ecological impact, reducing costs and mortality of hospital-acquired MDR BSIs.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
While, for a long time, the role of mitochondria in sperm physiology and pathology has been largely ignored, recent research points out the mitochondria as a major organelle with key roles in sperm ...function both under physiological and biotechnological conditions. This paper briefly reviews these novel findings regarding the role of mitochondria in sperm, paying special attention to the most practical, readily applicable, aspects of the topic such as their role as a major source of the sublethal damage that sperm experiments after cryopreservation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Felids are important in the epidemiology of Toxoplasma gondii because they are the only hosts that can excrete the environmentally resistant oocysts in their feces. Cats acquire T. gondii infection ...in nature by ingesting tissues of small mammals and birds. Serum samples of 223 feral marsupials and 174 feral rodents captured in 7 segments of the Atlantic Forest of the State of Pernambuco, northeastern region of Brazil, and in urban areas of the municipality of Recife were examined for antibodies to T. gondii by the modified agglutination test (MAT). Antibodies (MAT ≥ 25) were found in 6.7% (15 of 223) of the marsupials and 5.7% (10 of 174) of the rodents. No association was observed between seropositivity in marsupials or rodents and sex, age, or different areas of collection (P > 0.05). This is the first study on the seroprevalence of T. gondii in marsupials and rodents performed in the Atlantic Forest of the northeastern region of Brazil. The presence of antibodies to T. gondii are reported for the first time in long-furred woolly mouse opossum (Micoureus demerarae), murine mouse opossum (Marmosa murina), brown four-eyed opossum (Metachirus nudicaudatus), and gray short-tailed opossum (Monodelphis domestica).
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Glycerol is, to date, the most widely used cryoprotectant to freeze stallion spermatozoa at concentrations between 2% and 5%. Cryoprotectant toxicity has been claimed to be the single most limiting ...factor for the success of cryopreservation. In order to evaluate the toxic effects of the concentrations of glycerol used in practice, stallion spermatozoa were incubated in Biggers Whitten and Whittingham (BWW) media supplemented with 0%, 0.5%, 1.5%, 2.5%, 3.5%, and 5% glycerol. In two additional experiments, a hyposmotic (75 mOsm/kg) and a hyperosmotic (900 mOsm/kg) control media were included. Sperm parameters evaluated included cell volume, membrane integrity, lipid peroxidation, caspase 3, 7, and 8 activation, mitochondrial membrane potential, and integrity of the cytoskeleton. Glycerol exerted toxicity at concentrations ≥ 3.5% and the maximal toxicity was observed at 5%. The actin cytoskeleton was especially sensitive to glycerol presence, inducing rapid F actin depolymerization at concentrations over 1.5%. The sperm membrane and the mitochondria were other structures affected. The toxicity of glycerol is apparently related to osmotic and nonosmotic effects. In view of our results the concentration of glycerol in the freezing media for stallion spermatozoa should not surpass 2.5%.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Systemic sclerosis (SSc) is an autoimmune disease that shows one of the highest mortality rates among rheumatic diseases. We perform a large genome-wide association study (GWAS), and meta-analysis ...with previous GWASs, in 26,679 individuals and identify 27 independent genome-wide associated signals, including 13 new risk loci. The novel associations nearly double the number of genome-wide hits reported for SSc thus far. We define 95% credible sets of less than 5 likely causal variants in 12 loci. Additionally, we identify specific SSc subtype-associated signals. Functional analysis of high-priority variants shows the potential function of SSc signals, with the identification of 43 robust target genes through HiChIP. Our results point towards molecular pathways potentially involved in vasculopathy and fibrosis, two main hallmarks in SSc, and highlight the spectrum of critical cell types for the disease. This work supports a better understanding of the genetic basis of SSc and provides directions for future functional experiments.
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