The knowledge of the population structure of a given species is of great importance for its conservation and for the management of its fishing exploitation, especially for sharks. The tiger shark ...(Galeocerdo cuvier Péron&Lesueur, 1822) is an apex predator species that is currently listed as “Near Threatened” on the International Union for the Conservation of Nature's (IUCN) Red List of Threatened Species. In this study, the tiger shark's genetic structure in the Metropolitan Region of Recife (MRR) and oceanic archipelago of Fernando de Noronha (FN) was investigated based on one mitochondrial and two nuclear DNA markers. In addition, sequenced data from other geographic sites were added into the mitochondrial analysis. The data showed moderate‐to‐high genetic diversity, and it is consistent with good resilience of G. cuvier in ecological terms. The structuring tests reinforced a global distinction of the species in two lineages, one being from the Indo‐Pacific and the other from the North Atlantic. Also, this analysis showed the close relationship between tiger sharks from Indo‐Pacific and South‐eastern coast of Brazil. The Bayesian and AMOVA tests indicated that tiger sharks from FN and MRR are genetically similar, forming a cohesive population. These analyses support live specimen translocations from beaches (where the attacks occur) to distant marine areas given we detected a historical cohesive population occurring between those beaches from MRR and FN Islands where the sharks migrate. This research is the first that has validated individual translocations as a green strategy in South‐western Atlantic.
The human malaria parasite Plasmodium vivax infects red blood cells through a key pathway that requires interaction between Duffy binding protein II (DBPII) and its receptor on reticulocytes, the ...Duffy antigen/receptor for chemokines (DARC). A high proportion of P. vivax-exposed individuals fail to develop antibodies that inhibit DBPII-DARC interaction, and genetic factors that modulate this humoral immune response are poorly characterized. Here, we investigate if DBPII responsiveness could be HLA class II-linked.
A community-based open cohort study was carried out in an agricultural settlement of the Brazilian Amazon, in which 336 unrelated volunteers were genotyped for HLA class II (DRB1, DQA1 and DQB1 loci), and their DBPII immune responses were monitored over time (baseline, 6 and 12 months) by conventional serology (DBPII IgG ELISA-detected) and functional assays (inhibition of DBPII-erythrocyte binding). The results demonstrated an increased susceptibility of the DRB1*13:01 carriers to develop and sustain an anti-DBPII IgG response, while individuals with the haplotype DRB1*14:02-DQA1*05:03-DQB1*03:01 were persistent non-responders. HLA class II gene polymorphisms also influenced the functional properties of DBPII antibodies (BIAbs, binding inhibitory antibodies), with three alleles (DRB1*07:01, DQA1*02:01 and DQB1*02:02) comprising a single haplotype linked with the presence and persistence of the BIAbs response. Modelling the structural effects of the HLA-DRB1 variants revealed a number of differences in the peptide-binding groove, which is likely to lead to altered antigen binding and presentation profiles, and hence may explain the differences in subject responses.
The current study confirms the heritability of the DBPII antibody response, with genetic variation in HLA class II genes influencing both the development and persistence of IgG antibody responses. Cellular studies to increase knowledge of the binding affinities of DBPII peptides for class II molecules linked with good or poor antibody responses might lead to the development of strategies for controlling the type of helper T cells activated in response to DBPII.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
As the worst global pandemic of the past century, coronavirus disease 2019 (COVID-19) has had a disproportionate effect on maintenance dialysis patients and their health care providers. At a virtual ...roundtable on June 12, 2020, Dialysis Outcomes and Practice Patterns Study (DOPPS) investigators from 15 countries in Asia, Europe, and the Americas described and compared the effects of COVID-19 on dialysis care, with recent updates added. Most striking is the huge difference in risk to dialysis patients and staff across the world. Per-population cases and deaths among dialysis patients vary more than 100-fold across participating countries, mirroring burden in the general population. International data indicate that the case-fatality ratio remains at 10% to 30% among dialysis patients, confirming the gravity of infection, and that cases are much more common among in-center than home dialysis patients. This latter finding merits urgent study because in-center patients often have greater community exposure, and in-center transmission may be uncommon under optimal protocols. Greater telemedicine use is a welcome change here to stay, and our community needs to improve emergency planning and protect dialysis staff from the next pandemic. Finally, the pandemic’s challenges have prompted widespread partnering and innovation in kidney care and research that must be sustained after this global health crisis.
The characteristics of carbon fiber-reinforced plastics allow a very broad range of uses. Drilling is often necessary to assemble different components, but this can lead to various forms of damage, ...such as delamination which is the most severe. However, a reduced thrust force can decrease the risk of delamination. In this work, two variables of the drilling process were compared: tool material and geometry, as well as the effect of feed rate and cutting speed. The parameters that were analyzed include: thrust force, delamination extension and mechanical strength through open-hole tensile test, bearing test, and flexural test on drilled plates. The present work shows that a proper combination of all the factors involved in drilling operations, like tool material, tool geometry and cutting parameters, such as feed rate or cutting speed, can lead to the reduction of delamination damage and, consequently, to the enhancement of the mechanical properties of laminated parts in complex structures, evaluated by open-hole, bearing, or flexural tests.
We investigate the environment of the nearest Herbig Ae star, HD 104237, with a multiwavelength combination of optical coronagraphic, near-IR, and mid-IR imaging supported by optical, UV, and ...far-ultraviolet spectroscopy. We confirm the presence of T Tauri stars associated with the Herbig Ae star HD 104237, noted by Feigelson et al. We find that two of the stars within 15arc sec of HD 104237 have IR excesses, potentially indicating the presence of circumstellar disks, in addition to the Herbig Ae star itself. We derive a new spectral type of A7.5Ve-A8Ve for HD 104237 and find log(L/L sub(o)) = 1.39. With these data, HD 104237 has an age of t ~ 5 Myr, in agreement with the estimates for the other members of the association. HD 104237 is still actively accreting, with a conspicuous UV/far-UV excess seen down to 1040 Aa, and is driving a bipolar microjet termed HH 669. This makes it the second, older Herbig Ae star now known to have a microjet. The presence of the microjet enables us to constrain the circumstellar disk to r < 0!!6 (70 AU) with an inclination angle of i = 18image from pole-on. The absence of a spatially extended continuum and fluorescent H sub(2) emission near Lyalpha is in agreement with the prediction of shadowed disk models for the IR spectral energy distribution. With the high spatial density of disks in this group of stars, proximity, and minimal reddening, HD 104237 and its companions should serve as ideal laboratories for probing the comparative evolution of planetary systems.
To identify new risk variants for chronic lymphocytic leukemia (CLL), we conducted a genome-wide association study of 299,983 tagging SNPs, with validation in four additional series totaling 2,503 ...cases and 5,789 controls. We identified four new risk loci for CLL at 2q37.3 (rs757978, FARP2; odds ratio (OR) = 1.39; P = 2.11 × 10−9), 8q24.21 (rs2456449; OR = 1.26; P = 7.84 × 10−10), 15q21.3 (rs7169431; OR = 1.36; P = 4.74 × 10−7) and 16q24.1 (rs305061; OR = 1.22; P = 3.60 × 10−7). We also found evidence for risk loci at 15q25.2 (rs783540, CPEB1; OR = 1.18; P = 3.67 × 10−6) and 18q21.1 (rs1036935; OR = 1.22; P = 2.28 × 10−6). These data provide further evidence for genetic susceptibility to this B-cell hematological malignancy.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Relative telomere length in peripheral blood leukocytes has been evaluated as a potential biomarker for renal cell carcinoma (RCC) risk in several studies, with conflicting findings.
We performed an ...analysis of genetic variants associated with leukocyte telomere length to assess the relationship between telomere length and RCC risk using Mendelian randomization, an approach unaffected by biases from temporal variability and reverse causation that might have affected earlier investigations.
Genotypes from nine telomere length-associated variants for 10 784 cases and 20 406 cancer-free controls from six genome-wide association studies (GWAS) of RCC were aggregated into a weighted genetic risk score (GRS) predictive of leukocyte telomere length.
Odds ratios (ORs) relating the GRS and RCC risk were computed in individual GWAS datasets and combined by meta-analysis.
Longer genetically inferred telomere length was associated with an increased risk of RCC (OR=2.07 per predicted kilobase increase, 95% confidence interval CI:=1.70–2.53, p<0.0001). As a sensitivity analysis, we excluded two telomere length variants in linkage disequilibrium (R2>0.5) with GWAS-identified RCC risk variants (rs10936599 and rs9420907) from the telomere length GRS; despite this exclusion, a statistically significant association between the GRS and RCC risk persisted (OR=1.73, 95% CI=1.36–2.21, p<0.0001). Exploratory analyses for individual histologic subtypes suggested comparable associations with the telomere length GRS for clear cell (N=5573, OR=1.93, 95% CI=1.50–2.49, p<0.0001), papillary (N=573, OR=1.96, 95% CI=1.01–3.81, p=0.046), and chromophobe RCC (N=203, OR=2.37, 95% CI=0.78–7.17, p=0.13).
Our investigation adds to the growing body of evidence indicating some aspect of longer telomere length is important for RCC risk.
Telomeres are segments of DNA at chromosome ends that maintain chromosomal stability. Our study investigated the relationship between genetic variants associated with telomere length and renal cell carcinoma risk. We found evidence suggesting individuals with inherited predisposition to longer telomere length are at increased risk of developing renal cell carcinoma.
This large Mendelian randomization study utilizes a risk score of telomere length associated genetic variants to demonstrate a strong association between longer predicted leukocyte telomere length and increased risk of developing common subtypes of renal cell carcinoma.
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