98 research outputs found
Provision of Spectacles Is Associated With Significant Improvement In Children's Self Reported Visual Function In Mexico
This study examines the self-reported benefit in visual function among Mexican children who have received glasses from Helen Keller International
Interaction between lactose and cadmium chloride in aqueous solutions as seen by diffusion coefficients measurements
Diffusion coefficients of an aqueous system containing cadmium chloride 0.100 mol · dm−3 and lactose at different concentrations at 25 °C have been measured, using a conductimetric cell and an automatic apparatus to follow diffusion. The cell relies on an open-ended capillary method and a conductimetric technique is used to follow the diffusion process by measuring the resistance of a solution inside the capillaries, at recorded times. From these results and by ab initio calculations, it was possible to obtain a better understanding of the effect of lactose on transport of cadmium chloride in aqueous solutions
Binary Mutual Diffusion Coefficients of Isoniazid Aqueous Solutions at (298.15 and 310.15) K
Binary mutual diffusion coefficients measured by the Taylor dispersion method in two different laboratories (University of Naples, Federico II, Italy, and University of Coimbra, Portugal) are reported for aqueous solutions of isoniazid at concentrations from (0.000 to 0.100) mol·dm−3 and at two temperatures (298.15 and 310.15) K. The hydrodynamic radii for the isoniazid in aqueous solution are calculated from the experimental results. In addition, the Hartley equation and the experimental diffusion coefficients are used to estimate activity coefficients for aqueous isoniazid at both temperature
Transcriptome profiling of grapevine seedless segregants during berry development reveals candidate genes associated with berry weight
Indexación: Web of Science; PubMedBackground
Berry size is considered as one of the main selection criteria in table grape breeding programs. However, this is a quantitative and polygenic trait, and its genetic determination is still poorly understood. Considering its economic importance, it is relevant to determine its genetic architecture and elucidate the mechanisms involved in its expression. To approach this issue, an RNA-Seq experiment based on Illumina platform was performed (14 libraries), including seedless segregants with contrasting phenotypes for berry weight at fruit setting (FST) and 6–8 mm berries (B68) phenological stages.
Results
A group of 526 differentially expressed (DE) genes were identified, by comparing seedless segregants with contrasting phenotypes for berry weight: 101 genes from the FST stage and 463 from the B68 stage. Also, we integrated differential expression, principal components analysis (PCA), correlations and network co-expression analyses to characterize the transcriptome profiling observed in segregants with contrasting phenotypes for berry weight. After this, 68 DE genes were selected as candidate genes, and seven candidate genes were validated by real time-PCR, confirming their expression profiles.
Conclusions
We have carried out the first transcriptome analysis focused on table grape seedless segregants with contrasting phenotypes for berry weight. Our findings contributed to the understanding of the mechanisms involved in berry weight determination. Also, this comparative transcriptome profiling revealed candidate genes for berry weight which could be evaluated as selection tools in table grape breeding programs.http://bmcplantbiol.biomedcentral.com/articles/10.1186/s12870-016-0789-
Cryopreservation of testicular tissue from the dog (Canis familiaris) and wild boar (Sus scrofa) by slow freezing and vitrification: Differences in cryoresistance according to cell type
8 Pág.Sperm cryopreservation is the most common procedure used to establish germplasm banks for endangered species - but sometimes sperm cells cannot be obtained. In such cases, freezing testicular tissue may be the only option. The testes contains germ cells at different stages of differentiation, including spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids, and spermatozoa, among which differences in cryoresistance might be expected. The present work compares the viability and DNA integrity of 'rounded' cells, and of elongated spermatids and spermatozoa, from the dog and wild boar, following the cryopreservation of testicular tissue by slow freezing or vitrification. Cell viability was analyzed by PI/SYBR14 staining, and DNA integrity via the TUNEL technique. For wild boar, no significant differences were seen between the two methods with respect to the percentage of viable cells, nor in the percentage of cells with DNA damage. In the dog, the percentage of viable rounded germ cells (65.0 ± 2.4%) was higher (P < 0.05) after vitrification than after slow freezing (45.1 ± 6.7%). No difference was found between the two methods in terms of the viability of elongated cells. For rounded cells, the percentage of intact DNA was greater (P < 0.05) after vitrification (90.5 ± 2.1%) than after slow freezing (42.6 ± 11.0%), while for elongated spermatids and spermatozoa it was higher (P < 0.05) after slow freezing (66.9 ± 6.1%) than after vitrification (50.7 ± 4.5%). Thus, the response to cryopreservation is cell type-, cryopreservation type-, and species-dependent. Vitrification would appear to be the most appropriate method for preserving dog testicular tissue given the associated high cell viability and low degree of DNA fragmentation, while in wild boar, either method might be used.This study was funded by grant PID2020-113288RB-100/AEI/10.13039/501100011033.Peer reviewe
Mutual and self-diffusion of charged porphyrines in aqueous solutions
a b s t r a c t We have investigated the diffusion properties for an ionic porphyrin in water. Specifically, for the {tetra-sodium tetraphenylporphyrintetrasulfonate (Na 4 TPPS) + water} binary system, the self-diffusion coefficients of TPPS 4À and Na + , and the mutual diffusion coefficients were experimentally determined as a function of Na 4 TPPS concentration from (0 to 4) Á 10 À3 mol Á dm À3 at T = 298.15 K. Absorption spectra for this system were obtained over the same concentration range. Molecular mechanics were used to compute size and shape of the TPPS 4À porphyrin. We have found that, at low solute concentrations ), the mutual diffusion coefficient sharply decreases as the concentration increases. This can be related to both the ionic nature of the porphyrin and complex associative processes in solution. Our experimental results are discussed on the basis of the Nernst equation, Onsager-Fuoss theory and porphyrin metal ion association. In addition, self-diffusion of TPPS 4À was used, together with the Stokes-Einstein equation, to determine the equivalent hydrodynamic radius of TPPS 4À . By approximating this porphyrin to a disk, we have estimated structural parameters of TPPS 4À . These were found to be in good agreement with those obtained using molecular mechanics. Our work shows how the self-diffusion coefficient of an ionic porphyrin in water is substantially different from the corresponding mutual-diffusion coefficient in both magnitude and concentration dependence. This aspect should be taken into account when diffusion-based transport is modelled for in vitro and in vivo applications of pharmaceutical relevance
Effect of storage temperature during transport of ovaries on in vitro embryo production in Iberian red deer (Cervus elaphus hispanicus)
Slow and ultra-rapid freezing protocols for cryopreserving roe deer (Capreolus capreolus) epididymal sperm collected at different times of year
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Centro de Investigación en Sanidad Animal (CISA) / Departamento de Reproducción animalThe roe deer is a monoestrous species with a very short rutting season. The present work reports the most suitable period for collecting epididymal sperm and describes the effect of two cooling rates on the post-thaw quality of sperm. Testes were collected 24–48 h after death. Samples of sperm flushed from the epididymis were subjected to either (1) dilution in a Tris-citric acid-glucose-egg yolk-based medium with glycerol, and slow freezing in straws, or (2) dilution in the same extender but replacing the glycerol with 100 mM of sucrose, and ultra-rapid freezing in pellets. Sperm motility, acrosome and membrane integrity, morphometry and morphological abnormalities were analysed before and after cryopreservation. Spermatogenic activity was investigated via histological examination of testis sections. Several testes collected between April, May and September showed no spermatogenic activity. All those collected in June–August showed spermatogenic activity. No significant difference was detected in the cryoresistance ratios associated with the conventional slow freezing, between sperm collected during the pre-rutting (April–May) and rutting (June–August) periods. No significant differences were seen between the slow-frozen-thawed and the ultra-rapid-frozen-thawed sperm in terms of percentage of viable sperm or the percentage of sperm with morphological abnormalities. Slow freezing returned significantly better (P<0.05) values for post-thaw acrosome integrity (43.3% vs. 25.0%) and straight-line velocity (19 μm/s vs. 4 μm/s). For both freezing methods, sperm heads were smaller post-thawing than pre-freezing (P<0.001). In conclusion, both the pre-rutting and rutting season are suitable periods for freezing roe deer sperm. Ultra-rapid freezing did not provide suitable results.This research was funded by MINECO/AEI/FEDER and EU grant AGL2017-85753-R. P. Bóveda was the recipient of a grant for pre-doctoral researchers from MINECO (AEI/FSE, UE). Octavio Mejía was the recipient of a research fellowship from the PASPA-DGAPA-UNAM (México). V.N. Flores-Gil was funded by FONDECYT-CONCYTEC (grant contract number 000245-2015-FONDECYT).Peer reviewe
Implantation of Mouse Embryonic Stem Cell-Derived Cardiac Progenitor Cells Preserves Function of Infarcted Murine Hearts
Stem cell transplantation holds great promise for the treatment of myocardial infarction injury. We recently described the embryonic stem cell-derived cardiac progenitor cells (CPCs) capable of differentiating into cardiomyocytes, vascular endothelium, and smooth muscle. In this study, we hypothesized that transplanted CPCs will preserve function of the infarcted heart by participating in both muscle replacement and neovascularization. Differentiated CPCs formed functional electromechanical junctions with cardiomyocytes in vitro and conducted action potentials over cm-scale distances. When transplanted into infarcted mouse hearts, CPCs engrafted long-term in the infarct zone and surrounding myocardium without causing teratomas or arrhythmias. The grafted cells differentiated into cross-striated cardiomyocytes forming gap junctions with the host cells, while also contributing to neovascularization. Serial echocardiography and pressure-volume catheterization demonstrated attenuated ventricular dilatation and preserved left ventricular fractional shortening, systolic and diastolic function. Our results demonstrate that CPCs can engraft, differentiate, and preserve the functional output of the infarcted heart
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