1. |
|
|
2. |
- Vergallo, A., et al.
(författare)
-
Association of plasma YKL-40 with brain amyloid-β levels, memory performance, and sex in subjective memory complainers
- 2020
-
Ingår i: Neurobiology of Aging. - : Elsevier BV. - 0197-4580. ; 96, s. 22-32
-
Tidskriftsartikel (refereegranskat)abstract
- Neuroinflammation, a key early pathomechanistic alteration of Alzheimer's disease, may represent either a detrimental or a compensatory mechanism or both (according to the disease stage). YKL-40, a glycoprotein highly expressed in differentiated glial cells, is a candidate biomarker for in vivo tracking neuroinflammation in humans. We performed a longitudinal study in a monocentric cohort of cognitively healthy individuals at risk for Alzheimer's disease exploring whether age, sex, and the apolipoprotein E ε4 allele affect plasma YKL-40 concentrations. We investigated whether YKL-40 is associated with brain amyloid-β (Aβ) deposition, neuronal activity, and neurodegeneration as assessed via neuroimaging biomarkers. Finally, we investigated whether YKL-40 may predict cognitive performance. We found an age-associated increase of YKL-40 and observed that men display higher concentrations than women, indicating a potential sexual dimorphism. Moreover, YKL-40 was positively associated with memory performance and negatively associated with brain Aβ deposition (but not with metabolic signal). Consistent with translational studies, our results suggest a potentially protective effect of glia on incipient brain Aβ accumulation and neuronal homeostasis. © 2020 Elsevier Inc.
|
|
3. |
|
|
4. |
- Vergallo, A., et al.
(författare)
-
Plasma amyloid beta 40/42 ratio predicts cerebral amyloidosis in cognitively normal individuals at risk for Alzheimer's disease
- 2019
-
Ingår i: Alzheimers & Dementia. - : Wiley. - 1552-5260 .- 1552-5279. ; 15:6, s. 764-775
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Blood-based biomarkers of pathophysiological brain amyloid beta (A beta) accumulation, particularly for preclinical target and large-scale interventions, are warranted to effectively enrich Alzheimer's disease clinical trials and management. Methods: We investigated whether plasma concentrations of the A beta(1-40)/A beta(1-42) ratio, assessed using the single-molecule array (Simoa) immunoassay, may predict brain A beta positron emission tomography status in a large-scale longitudinal monocentric cohort (N = 276) of older individuals with subjective memory complaints. We performed a hypothesis-driven investigation followed by a no-apriori hypothesis study using machine learning. Results: The receiver operating characteristic curve and machine learning showed a balanced accuracy of 76.5% and 81%, respectively, for the plasma A beta(1-40)/A beta(1-42) ratio. The accuracy is not affected by the apolipoprotein E (APOE) epsilon 4 allele, sex, or age. Discussion: Our results encourage an independent validation cohort study to confirm the indication that the plasma A beta(1-40)/A beta(1-42) ratio, assessed via Simoa, may improve future standard of care and clinical trial design. (C) 2019 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
|
|
5. |
- Martinez, C. A., et al.
(författare)
-
Peroxidized mineral oil increases the oxidant status of culture media and inhibits in vitro porcine embryo development
- 2017
-
Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 103, s. 17-23
-
Tidskriftsartikel (refereegranskat)abstract
- The use of oils with undetected alterations is a long-recognized problem for in vitro embryo production systems. Since peroxides in oils have been associated with reduced embryo production outcomes, our goals were (1) to evaluate the effects of a batch of mineral oil (MO) that was suspected to be altered on the in vitro production of pig embryos and (2) to determine oil peroxide values throughout culture and the transfer of oxidant agents from oil to culture media. Sunflower oil, which has a completely different chemical composition than MO but a higher oxidative status, and unaltered MO were used as controls. Oocyte maturation, fertilization and embryo development were affected differently depending on the oil overlay used. While the suspected MO was not able to sustain in vitro maturation and fertilization, the oocytes incubated in the presence of sunflower oil were matured and fertilized similarly to those of the unaltered MO group. Moreover, the cleavage rate of presumed zygotes cultured under the suspected MO was severely reduced compared with those cultured under the other oils, and none of the cleaved embryos developed to the blastocyst stage. Although the cleavage rates in the sunflower oil and unaltered MO groups were similar, embryos cultured under sunflower oil also failed to develop to the blastocyst stage. Our results revealed that the suspected MO and sunflower oil had similar levels of peroxides and that these levels were much higher than those of the unaltered MO. The total oxidant status was higher in media incubated under peroxidized oils than in fresh media or media incubated without an oil overlay or under unaltered MO, indicating that oxidant agents were transferred to the incubation media. However, unlike the sunflower oil group, the culture media incubated under the suspected MO had high levels of total oxidant status and low levels of hydrogen peroxide and reactive oxygen species, suggesting the presence of other unknown oxidant agents in that oil. These results indicate that a peroxidized MO overlay dramatically decreases embryo production outcomes. This decrease could be associated with the higher peroxide values of the oil but cannot be explained by the levels of hydrogen peroxide and reactive oxygen species transferred from the oil to the culture media. It is likely that different oxidant agent(s) and/or other toxic compounds present in the peroxidized MO are responsible for its damaging effects on oocytes and embryos. (C) 2017 Elsevier Inc. All rights reserved.
|
|
6. |
- Martinez, C. A., et al.
(författare)
-
Three-to-5-day weaning-to-estrus intervals do not affect neither efficiency of collection nor in vitro developmental ability of in vivo-derived pig zygotes
- 2020
-
Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 141, s. 48-53
-
Tidskriftsartikel (refereegranskat)abstract
- An efficient system to collect large numbers of vital zygotes is a pre-requisite for application of zygote genome-editing technology, including development of efficient models for xenotransplantation using pigs. Owing to the sub-optimal in vitro production of zygotes in pigs, efficient collection of in vivo developed zygotes is required. Timing of ovulation is a key factor to sustain efficiency since the interval between pronuclear formation and the first division is very short in pigs. The weaning-to-estrus interval can, due to its inverse relation with length of estrus and time of ovulation, interfere with ovulation and make it asynchronous, which reduces the probability of obtaining zygotes. This retrospective study compared the effects of three weaning-to-estrus intervals of 3, 4 or 5 days on zygote collection efficiency in a total of 17 trials over a 3-year period including 223 sows. Donor sows in groups of 10-15 animals were super-ovulated with eCG 24 h after weaning and those in estrus at 48-72 h post-eCG were immediately treated with hCG, followed by insemination 6 and 24 h thereafter. Collected structures during laparotomy on Day 2 (Day 0: onset of estrus) were morphologically evaluated and only those with a single cell and two visible polar bodies were considered as zygotes. Zygotes were injected with CRISPRCas9 editor mixture and cultured for 6 days to evaluate their developmental ability against non-injected control zygotes. Of all recovered structures (N = 5,468), 67.4%, 30.8% and 1.8% were zygotes, 2-cell embryos and oocytes-degenerated embryos, respectively. The different weaning-to-estrus intervals did not affect either the percentages of collected zygotes (range: 64.1%-70.0%) or the percentages of sows with zygotes at collection time (range: 69.0%-73.3%). The weaning-to-estrus intervals did not affect the in vitro developmental ability of zygotes. After 24 h of culture, 78.1 +/- 2.0% and 95.1 +/- 0.6 (P amp;lt; 0.05) of injected (N = 2,345) and non-injected (N = 335) zygotes, respectively, developed to 2-to-4-cell embryo stage. The total efficiency of the system was 64.1 +/- 2.2% and 85.8 +/- 1.5% (P amp;lt; 0.05) for injected and noninjected zygotes, respectively. In conclusion, the results indicate that neither the efficiency of collecting in vivo derived porcine zygotes from superovulated sows nor the zygote ability to develop to blastocyst after cytoplasmic genome-editing injection were affected by a weaning-to-estrus interval between 3-to-5 days. (C) 2019 Elsevier Inc. All rights reserved.
|
|
7. |
- Minelli, Caterina, et al.
(författare)
-
Versailles project on advanced materials and standards (VAMAS) interlaboratory study on measuring the number concentration of colloidal gold nanoparticles
- 2022
-
Ingår i: Nanoscale. - : Royal Society of Chemistry (RSC). - 2040-3372 .- 2040-3364. ; 14, s. 4690-4704
-
Tidskriftsartikel (refereegranskat)abstract
- We describe the outcome of a large international interlaboratory study of the measurement of particle number concentration of colloidal nanoparticles, project 10 of the technical working area 34, "Nanoparticle Populations" of the Versailles Project on Advanced Materials and Standards (VAMAS). A total of 50 laboratories delivered results for the number concentration of 30 nm gold colloidal nanoparticles measured using particle tracking analysis (PTA), single particle inductively coupled plasma mass spectrometry (spICP-MS), ultraviolet-visible (UV-Vis) light spectroscopy, centrifugal liquid sedimentation (CLS) and small angle X-ray scattering (SAXS). The study provides quantitative data to evaluate the repeatability of these methods and their reproducibility in the measurement of number concentration of model nanoparticle systems following a common measurement protocol. We find that the population-averaging methods of SAXS, CLS and UV-Vis have high measurement repeatability and reproducibility, with between-labs variability of 2.6%, 11% and 1.4% respectively. However, results may be significantly biased for reasons including inaccurate material properties whose values are used to compute the number concentration. Particle-counting method results are less reproducibile than population-averaging methods, with measured between-labs variability of 68% and 46% for PTA and spICP-MS respectively. This study provides the stakeholder community with important comparative data to underpin measurement reproducibility and method validation for number concentration of nanoparticles.
|
|
8. |
- Alminana, C, et al.
(författare)
-
Adjustments in IVF system for individual boars: Value of additives and time of sperm-oocyte co-incubation
- 2005
-
Ingår i: Theriogenology. - : Elsevier. - 0093-691X .- 1879-3231. ; 64:8, s. 1783-1796
-
Tidskriftsartikel (refereegranskat)abstract
- In vitro fertilization (IVF) in pigs is still considered sub-optimal, due to the variable occurrence of polyspermy, variability mainly related to sperm differences. The present study was conducted in an attempt to increase the efficiency of the in vitro production of porcine embryos by optimizing the in vitro fertilization (IVF) protocol for individual males, with regard to the composition of the fertilization medium (experiments 1 and 2) and the length of gamete co-incubation time (experiment 3). A total of 5943 COCs were in vitro matured (IVM) and inseminated with frozen-thawed spermatozoa froth 2 boars (A and B). Experiment 1 determined the effect of additives caffeine (2 mM), hyaluronic acid (HA; [0.5 mg/mL]) and adenosine (10 mu M), alone or in combination, to the IVF-medium during sperm-oocyte co-incubation. Experiment 2 tested the addition of various HA (0, 0.5, 1.0 and 1.5 mg/ml) and adenosine (0, 10, 20 and 40 mu M) concentrations in the fertilization medium; while experiment 3 investigated the effect of two periods of sperm-oocyte co-incubation (10 thin or 6h). In the case of 10 min sperm-oocyte co-incubation, oocytes with attaching spermatozoa were further cultured in IVF-medium containing no spermatozoa until the 6 h of insemination was completed. Presumptive zygotes were cultured in embryo culture medium for 1215 h to assess fertilization parameters. In experiment 1, only caffeine significantly influenced the outcome of fertilization, albeit being a clearly boar-dependent effect. In experiment 2, similar boar differences were seen for HA supplementation while presence of exogenous adenosine did not influence fertilization parameters in either boar. The results of experiment 3 demonstrated that a short co-incubation time significantly (P less than 0.001) increased penetration rate and mean number of spermatozoa per oocyte (74.9 +/- 3.9% versus 62.7 +/- 3.9% and 1.5 +/- 3.2 versus 1.3 +/- 3.5 for 10 min or 6 h, respectively), but reduced monospermy (P less than 0.001, 57.9 +/- 2.5% versus 70.0 +/- 2.8%) when boar A was used. However, such effects were not seen with boar B, in which sperm-oocyte co-incubation time did not affect the efficiency of fertilization. In view of the present results, a preliminary screening for each individual male is required to select optimal conditions for IVF. (c) 2005 Elsevier Inc. All rights reserved.
|
|
9. |
- Aranha, M. R., et al.
(författare)
-
Basal forebrain atrophy along the Alzheimer's disease continuum in adults with Down syndrome
- 2023
-
Ingår i: Alzheimers & Dementia. - 1552-5260. ; 19:11, s. 4817-4827
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundBasal forebrain (BF) degeneration occurs in Down syndrome (DS)-associated Alzheimer's disease (AD). However, the dynamics of BF atrophy with age and disease progression, its impact on cognition, and its relationship with AD biomarkers have not been studied in DS. MethodsWe included 234 adults with DS (150 asymptomatic, 38 prodromal AD, and 46 AD dementia) and 147 euploid controls. BF volumes were extracted from T-weighted magnetic resonance images using a stereotactic atlas in SPM12. We assessed BF volume changes with age and along the clinical AD continuum and their relationship to cognitive performance, cerebrospinal fluid (CSF) and plasma amyloid/tau/neurodegeneration biomarkers, and hippocampal volume. ResultsIn DS, BF volumes decreased with age and along the clinical AD continuum and significantly correlated with amyloid, tau, and neurofilament light chain changes in CSF and plasma, hippocampal volume, and cognitive performance. DiscussionBF atrophy is a potentially valuable neuroimaging biomarker of AD-related cholinergic neurodegeneration in DS.
|
|
10. |
- Cambra, J. M., et al.
(författare)
-
The cytokine platelet factor 4 successfully replaces bovine serum albumin for the in vitro culture of porcine embryos
- 2020
-
Ingår i: Theriogenology. - : ELSEVIER SCIENCE INC. - 0093-691X .- 1879-3231. ; 148, s. 201-207
-
Tidskriftsartikel (refereegranskat)abstract
- The cytokine platelet factor 4 (PF4) enhances differentiation and cell viability of different stem cells lines in vitro. This study investigated whether PF4 addition to customary pig embryo semi-defined culture media can improve their developmental outcome (Experiment 1) and ultimately replace the need for bovine serum albumin (BSA, Experiment 2). Experiment 1 added PF4 (100-1000 ng/mL, 0 = control) to NCSU-23 with 0.4 mg/mL BSA culturing 3430 presumptive zygotes. Experiment 2 added PF4 (100 -1000 ng/mL, 0 = Control-PVA) to a BSA-free medium (NCSU-23 with 0.3 mg/mL PVA) culturing 3820 presumptive zygotes. Zygote culture in NCSU-23 with 0.4 mg/mL BSA was used as overall control. All groups of Experiment 1 displayed similar rates of day 2-cleavage (range: 65.0 +/- 10.9 to 70.0 +/- 5.8%); of day 7-blastocyst rates (range: 46.6 +/- 10.0 to 56.4 +/- 8.2%) and of total day 7-blastocyst efficiency (range: 32.3 +/- 8.3 to 37.2 +/- 7.3%). Addition of PF4 did not affect total cell numbers of day 7 blastocysts (range: 44.1 +/- 23.2 to 50.5 +/- 26.4). In Experiment 2, PF4 accelerated embryo development, increasing (P < 0.01) blastocyst yield compared to 0-PF4, and blastocyst formation by day 5 adding PF4 100-500 ng/mL (range: 29.9 +/- 7.8 to 31.8 +/- 5.5%; P < 0.05) compared with BSA-control (17.2 +/- 8.2%) and PF4 1000 ng/mL (15.5 +/- 7.9%); showing similar blastocyst rates (range: 42.0 +/- 11.5 to 49.3 +/- 10.0%), total efficiency (28.0 +/- 8.2 to 32.3 +/- 7.1%) total cell numbers (range: 42.6 +/- 19.3 to 45.7 +/- 23.9) as BSA-controls. In conclusion, although PF4 did not show additive improvement under usual semi-defined, BSA-supplemented embryo media, it successfully replaced BSA sustaining porcine blastocyst production in chemically defined conditions. (C) 2019 Elsevier Inc. All rights reserved.
|
|