Under sulfur (S) deficiency, crosstalk between nutrients induced accumulation of other nutrients, particularly molybdenum (Mo). This disturbed balanced between S and Mo could provide a way to detect ...S deficiency and therefore avoid losses in yield and seed quality in cultivated species. Under hydroponic conditions, S deprivation was applied to Brassica napus to determine the precise kinetics of S and Mo uptake and whether sulfate transporters were involved in Mo uptake. Leaf contents of S and Mo were also quantified in a field-grown S deficient oilseed rape crop with different S and N fertilization applications to evaluate the Mo:S ratio, as an indicator of S nutrition. To test genericity of this indicator, the Mo:S ratio was also assessed with other cultivated species under different controlled conditions. During S deprivation, Mo uptake was strongly increased in B. napus. This accumulation was not a result of the induction of the molybdate transporters, Mot1 and Asy, but could be a direct consequence of Sultr1.1 and Sultr1.2 inductions. However, analysis of single mutants of these transporters in Arabidopsis thaliana suggested that other sulfate deficiency responsive transporters may be involved. Under field conditions, Mo content was also increased in leaves by a reduction in S fertilization. The Mo:S ratio significantly discriminated between the plots with different rates of S fertilization. Threshold values were estimated for the hierarchical clustering of commercial crops according to S status. The use of the Mo:S ratio was also reliable to detect S deficiency for other cultivated species under controlled conditions. The analysis of the leaf Mo:S ratio seems to be a practical indicator to detect early S deficiency under field conditions and thus improve S fertilization management.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Recent systems for Human Immunodeficiency Virus 1 (HIV-1) viral load (VL) monitoring allow one-by-one analysis and fast turn-around-time for results. VL measurement on two rapid recently ...commercialized systems, GeneXpert (Cepheid) and Veris (Beckman Coulter) was compared to classical methods.
Plasma specimen from HIV-1 (group M) positive patients (n = 129) initially quantified with Abbott RealTime HIV-1 and Generic HIV-VL Biocentric assays were retrospectively tested with GeneXpert and Veris.
Valid results on all techniques were obtained for 116/129 specimens composed of 89 Abbott quantifiable VL (38 B, 51 non-B subtypes) range: 2.09-7.20 log cp/mL and 27 plasma (9 B, 18 non-B) with Abbott-VL below the limit of quantification (LLQ). All techniques showed good correlation and agreement with a lowest Spearman correlation coefficient of 0.86. Compared to Abbott, the mean bias was 0.35 (95% CI: 0.25-0.45), 0.44 (0.36-0.53) and - 0.04 (- 0.13-0.05) for Biocentric, Beckman and Cepheid, respectively. A difference over 0.5 log cp/mL between VL-quantification of the same sample was observed for 19, 9 and 6 samples with Biocentric, Beckman and Cepheid, respectively. No influence of HIV-1 subtypes on VL was identified. Among 29 samples below LLQ on Abbott, only one was detected and quantified with the Veris assay (38 cp/mL), none with Cepheid.
Both random access systems from Cepheid and Beckman appear well designed for quantifying plasma HIV-1 VL, are easy to handle, fast and fully automated. The slight observed differences suggest to follow the current guidelines recommending the use of the same technique over time for patient viral load monitoring.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
One of the main limiting factors of plant yield is drought, and while the physiological responses to this environmental stress have been broadly described, research addressing its impact on mineral ...nutrition is scarce. Brassica napus and Triticum aestivum were subjected to moderate or severe water deficit, and their responses to drought were assessed by functional ionomic analysis, and derived calculation of the net uptake of 20 nutrients. While the uptake of most mineral nutrients decreased, Fe, Zn, Mn, and Mo uptake were impacted earlier and at a larger scale than most physiological parameters assessed (growth, ABA concentration, gas exchanges and photosynthetic activity). Additionally, in B. napus, the patterns of 183 differentially expressed genes in leaves related to the ionome (known ionomic genes, KIGs) or assumed to be involved in transport of a given nutrient were analyzed. This revealed three patterns of gene expression under drought consisting of up (transport of Cl and Co), down (transport of N, P, B, Mo, and Ni), or mixed levels (transport of S, Mg, K, Zn, Fe, Cu, or Mn) of regulation. The three patterns of gene regulations are discussed in relation to specific gene functions, changes of leaf ionomic composition and with consideration of the crosstalks that have been established between elements. It is suggested that the observed reduction in Fe uptake occurred via a specific response to drought, leading indirectly to reduced uptake of Zn and Mn, and these may be taken up by common transporters encoded by genes that were downregulated.
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In wheat and rapeseed, drought downregulates the uptake of Fe, Mo, Zn, and Mn before reduction of growth, and this was associated with differential expressions of transport‐related genes.
Virological failure (VF) in patients on maraviroc-based treatment has been associated with altered HIV tropism and resistance to maraviroc. This multicentre study aimed to characterize VF in patients ...treated with maraviroc.
We analysed 27 patients whose treatment failed between 2008 and 2011. They had been screened for HIV tropism before maraviroc initiation using population-based V3 genotyping. HIV-1 tropism and resistance of R5 viruses to maraviroc at VF and at baseline were determined retrospectively using an ultrasensitive recombinant virus assay (RVA).
Viruses from 27 patients given maraviroc on the basis of the R5 genotype were characterized at the time of treatment failure. The RVA indicated that 12 patients harboured CXCR4-using viruses and 15 (56%) had pure R5 viruses at failure. One-third of those harbouring CXCR4-using viruses (4/12) were infected with R5X4/X4 viruses according to the RVA before maraviroc initiation. We analysed the phenotypic resistance to maraviroc of four patients harbouring R5 viruses at failure; two harboured viruses whose maximum percentage inhibition was reduced by 65%-90%, while the other two were infected with susceptible viruses. All patients had effective concentrations of drugs.
Half of the maraviroc-treated patients who experienced VF harboured CXCR4-using viruses at failure, one-third of them were detected by a phenotypic method before maraviroc initiation. Phenotypic assessment of R5 virus resistance to CCR5 antagonists at failure could help optimize antiretroviral therapy.
Copy number variations (CNVs) are rare genomic deletions and duplications that can affect brain and behaviour. Previous reports of CNV pleiotropy imply that they converge on shared mechanisms at some ...level of pathway cascades, from genes to large-scale neural circuits to the phenome. However, existing studies have primarily examined single CNV loci in small clinical cohorts. It remains unknown, for example, how distinct CNVs escalate vulnerability for the same developmental and psychiatric disorders. Here we quantitatively dissect the associations between brain organization and behavioural differentiation across 8 key CNVs. In 534 CNV carriers, we explored CNV-specific brain morphology patterns. CNVs were characteristic of disparate morphological changes involving multiple large-scale networks. We extensively annotated these CNV-associated patterns with ~1,000 lifestyle indicators through the UK Biobank resource. The resulting phenotypic profiles largely overlap and have body-wide implications, including the cardiovascular, endocrine, skeletal and nervous systems. Our population-level investigation established brain structural divergences and phenotypical convergences of CNVs, with direct relevance to major brain disorders.
Although indirect evidence suggests the male genital tract as a possible source of persistent HIV shedding in semen during antiretroviral therapy, this phenomenon is poorly understood due to the ...difficulty of sampling semen-producing organs in HIV+ asymptomatic individuals.
Using a range of molecular and cell biological techniques, this study investigates SIV infection within reproductive organs of macaques during the acute and chronic stages of the disease. We demonstrate for the first time the presence of SIV in the testes, epididymides, prostate and seminal vesicles as early as 14 days post-inoculation. This infection persists throughout the chronic stage and positively correlates with blood viremia. The prostate and seminal vesicles appear to be the most efficiently infected reproductive organs, followed by the epididymides and testes. Within the male genital tract, mostly T lymphocytes and a small number of germ cells harbour SIV antigens and RNA. In contrast to the other organs studied, the testis does not display an immune response to the infection. Testosteronemia is transiently increased during the early phase of the infection but spermatogenesis remains unaffected.
The present study reveals that SIV infection of the macaque male genital tract is an early event and that semen-producing organs display differential infection levels and immune responses. These results help elucidate the origin of HIV in semen and constitute an essential base to improving the design of antiretroviral therapies to eradicate virus from semen.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study describes a method for the detection and characterization of mycosporines-like compounds including mycosporine and MAAs in lichens, using HPLC-DAD–MSn, UPLC–HRMS and HPTLC–UV. Display ...omitted
► An optimized technique for the purification of mycosporines and MAAs in lichens. ► Detection and identification of mycosporines using HPTLC and -HPLC-DAD–MS. ► Lichens appear to be a great reservoir of mycosporines. ► Mycosporines and MAAs are investigated in cyanolichens series. ► Mycosporine hydroxyglutamicol is here described for the first time.
Mycosporine-like compounds, comprising mycosporines and mycosporine-like amino acids (MAAs) are UV protecting secondary metabolites described in organisms such as fungi, algae, cyanobacteria or animals. Lichens however, were only poorly investigated for such constituents so far. Here, a method for the characterization of mycosporines and MAAs in purified aqueous extracts, involving HPTLC coupled to spectrophotodensitometry, HPLC-DAD–MSn and UPLC–HRMS analysis, is described. This optimized protocol was validated on three algae and one cyanolichen containing known MAAs and mycosporines, and then applied to 18 cyanolichen species. Analyses revealed the presence of five already described mycosporine-like compounds in the investigated species, including mycosporine serinol in Lichina and Peltigera species and mycosporine glutamicol in Degelia plumbea. Apart from that, eight unknown mycosporine-like compounds were detected and tentatively characterized on the basis of their DAD spectra and their MSn and HRMS data: two in the alga Porphyra dioica and six in cyanolichen species belonging to the genera Degelia, Nephroma and Stereocaulon. From Nephroma laevigatum, the mycosporine hydroxyglutamicol was preparatively isolated and identified through HRMS, 1D and 2D NMR spectroscopic data. The optimized analytical protocol allowed the characterization of mycosporine-like compounds in small amounts of material and confirmed the potential of cyanolichens as a source of mycosporine compounds. It should also be applicable to investigate lichen species with green algae photobionts for mycosporine-like compounds.
One of the co-authors, Marianne B.M. van den Bree has had her name incorrectly abbreviated by citation manager. It was stated as "Bree MBMVD14", but has been updated to "van den Bree, M.B.M." in the ...HTML, PDF, and XML versions of this article.
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