scholarly journals Maternal Diabetes Causes Mitochondrial Dysfunction and Meiotic Defects in Murine Oocytes

2009 ◽  
Vol 23 (10) ◽  
pp. 1603-1612 ◽  
Author(s):  
Qiang Wang ◽  
Ann M. Ratchford ◽  
Maggie M.-Y. Chi ◽  
Erica Schoeller ◽  
Antonina Frolova ◽  
...  
Keyword(s):  
Tricarboxylic Acid Cycle ◽  
Maternal Diabetes ◽  
Meiotic Spindle ◽  
Metabolic Dysfunction ◽  
Diabetic Mice ◽  
Abnormal Distribution ◽  
Mitochondrial Dna Copy Number ◽  
Transmission Electron ◽  
The One ◽  
Zygote Stage

Abstract The adverse effects of maternal diabetes on embryo development and pregnancy outcomes have recently been shown to occur as early as the one-cell zygote stage. The hypothesis of this study was that maternally inherited mitochondria in oocytes from diabetic mice are abnormal and thus responsible in part for this latency of developmental compromise. In ovulated oocytes from diabetic mice, transmission electron microscopy revealed an alteration in mitochondrial ultrastructure, and the quantitative analysis of mitochondrial DNA copy number demonstrated an increase. The levels of ATP and tricarboxylic acid cycle metabolites in diabetic oocytes were markedly reduced compared with controls, suggesting a mitochondrial metabolic dysfunction. Abnormal distribution of mitochondria within maturing oocytes also was seen in diabetic mice. Furthermore, oocytes from diabetic mice displayed a higher frequency of spindle defects and chromosome misalignment in meiosis, resulting in increased aneuploidy rates in ovulated oocytes. Collectively, our results suggest that maternal diabetes results in oocyte defects that are transmitted to the fetus by two routes: first, meiotic spindle and chromatin defects result in nondisjunction leading to embryonic aneuploidy; second, structural and functional abnormalities of oocyte mitochondria, through maternal transmission, provide the embryo with a dysfunctional complement of mitochondria that may be propagated during embryogenesis.

scholarly journals Maternal Diabetes Causes Mitochondrial Dysfunction and Meiotic Defects in Murine Oocytes

2009 ◽  
Vol 94 (9) ◽  
pp. 3618-3618
Author(s):  
Qiang Wang ◽  
Ann M. Ratchford ◽  
Maggie M.-Y. Chi ◽  
Erica Schoeller ◽  
Antonina Frolova ◽  
...  
Keyword(s):  
Tricarboxylic Acid Cycle ◽  
Maternal Diabetes ◽  
Meiotic Spindle ◽  
Metabolic Dysfunction ◽  
Diabetic Mice ◽  
Abnormal Distribution ◽  
Mitochondrial Dna Copy Number ◽  
Transmission Electron ◽  
The One ◽  
Zygote Stage

The adverse effects of maternal diabetes on embryo development and pregnancy outcomes have recently been shown to occur as early as the one-cell zygote stage. The hypothesis of this study was that maternally inherited mitochondria in oocytes from diabetic mice are abnormal and thus responsible in part for this latency of developmental compromise. In ovulated oocytes from diabetic mice, transmission electron microscopy revealed an alteration in mitochondrial ultrastructure, and the quantitative analysis of mitochondrial DNA copy number demonstrated an increase. The levels of ATP and tricarboxylic acid cycle metabolites in diabetic oocytes were markedly reduced compared with controls, suggesting a mitochondrial metabolic dysfunction. Abnormal distribution of mitochondria within maturing oocytes also was seen in diabetic mice. Furthermore, oocytes from diabetic mice displayed a higher frequency of spindle defects and chromosome misalignment in meiosis, resulting in increased aneuploidy rates in ovulated oocytes. Collectively, our results suggest that maternal diabetes results in oocyte defects that are transmitted to the fetus by two routes: first, meiotic spindle and chromatin defects result in nondisjunction leading to embryonic aneuploidy; second, structural and functional abnormalities of oocyte mitochondria, through maternal transmission, provide the embryo with a dysfunctional complement of mitochondria that may be propagated during embryogenesis.

scholarly journals Loss of PDK1 Induces Meiotic Defects in Oocytes From Diabetic Mice

2021 ◽  
Vol 9 ◽  
Author(s):  
Juan Ge ◽  
Na Zhang ◽  
Shoubin Tang ◽  
Feifei Hu ◽  
Xiaojing Hou ◽  
...  
Keyword(s):  
Pyruvate Dehydrogenase ◽  
Maternal Diabetes ◽  
Diabetic Mouse ◽  
Oocyte Quality ◽  
Pyruvate Dehydrogenase Kinase ◽  
Metabolic Dysfunction ◽  
Diabetic Mice ◽  
Α Subunit ◽  
Oocyte Competence ◽  
Beneficial Effects

Maternal diabetes has been shown to impair oocyte quality; however, the underlying mechanisms remain unclear. Here, using a streptozotocin (STZ)-induced diabetic mouse model, we first detected and reduced expression of pyruvate dehydrogenase kinase 1 (PDK1) in diabetic oocytes, accompanying with the lowered phosphorylation of serine residue 232 on α subunit of the pyruvate dehydrogenase (PDH) complex (Ser232-PDHE1α). Importantly, forced expression of PDK1 not only elevated the phosphorylation level of Ser232-PDHE1α, but also partly prevented the spindle disorganization and chromosome misalignment in oocytes from diabetic mice, with no beneficial effects on metabolic dysfunction. Moreover, a phospho-mimetic S232D-PDHE1α mutant is also capable of ameliorating the maternal diabetes-associated meiotic defects. In sum, our data indicate that PDK1-controlled Ser232-PDHE1α phosphorylation pathway mediates the effects of diabetic environment on oocyte competence.

scholarly journals One-Cell Zygote Transfer from Diabetic to Nondiabetic Mouse Results in Congenital Malformations and Growth Retardation in Offspring

Endocrinology ◽  
2007 ◽  
Vol 149 (2) ◽  
pp. 466-469 ◽  
Author(s):  
Amanda Wyman ◽  
Anil B. Pinto ◽  
Rachael Sheridan ◽  
Kelle H. Moley
Keyword(s):  
Morphological Changes ◽  
Maternal Diabetes ◽  
First Trimester ◽  
Blastocyst Stage ◽  
Neural Tube Closure ◽  
Limb Deformities ◽  
Mouse Zygotes ◽  
The One ◽  
Zygote Stage

Fetuses of type 1 and 2 diabetic women experience higher incidences of malformations and fetal death as compared with nondiabetics, even when they achieve adequate glycemic control during the first trimester. We hypothesize that maternal diabetes adversely affects the earliest embryonic stage after fertilization and programs the fetus to experience these complications. To test this hypothesis, we transferred either one-cell mouse zygotes or blastocysts from either streptozotocin-induced diabetic or control mice into nondiabetic pseudopregnant female recipients. We then evaluated the fetuses at embryonic d 14.5 to assess fetal growth and the presence or absence of malformations. We found that fetuses from the diabetic mice transferred at the blastocyst stage but also as early as the one-cell zygote stage displayed significantly higher rates of malformations consistent with neural tube closure problems and abdominal wall and limb deformities. In addition, both these groups of fetuses were significantly growth retarded. To determine if this phenomenon was due to high glucose concentrations, two-cell embryos were cultured to a blastocyst stage in 52 mmd-glucose or l-glucose as an osmotic control, transferred into nondiabetic pseudopregnant mice, and examined at embryonic d 14.5. These embryos did not demonstrate any evidence of malformations, however, they did experience significantly higher rates of resorptions, lower implantation rates, and they were significantly smaller at embryonic d 14.5. In summary, exposure to maternal diabetes during oogenesis, fertilization, and the first 24 h was enough to program permanently the fetus to develop significant morphological changes.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

P20 phosphor on polyimide as a large area high-resolution transmission screen for slow scan CCD systems

1995 ◽  
Vol 53 ◽  
pp. 20-21
Author(s):  
C. C. Ahn ◽  
S. Karnes ◽  
M. Lvovsky ◽  
C. M. Garland ◽  
H. A. Atwater ◽  
...  
Keyword(s):  
Mechanical Stability ◽  
High Energy ◽  
Practical Implementation ◽  
Line Pair ◽  
Modulation Transfer ◽  
Large Area ◽  
Ccd Imaging ◽  
Transmission Electron ◽  
The One ◽  
Beam Broadening

The bane of CCD imaging systems for transmission electron microscopy at intermediate and high voltages has been their relatively poor modulation transfer function (MTF), or line pair resolution. The problem originates primarily with the phosphor screen. On the one hand, screens should be thick so that as many incident electrons as possible are converted to photons, yielding a high detective quantum efficiency(DQE). The MTF diminishes as a function of scintillator thickness however, and to some extent as a function of fluorescence within the scintillator substrates. Fan has noted that the use of a thin layer of phosphor beneath a self supporting 2μ, thick Al substrate might provide the most appropriate compromise for high DQE and MTF in transmission electron microcscopes which operate at higher voltages. Monte Carlo simulations of high energy electron trajectories reveal that only little beam broadening occurs within this thickness of Al film. Consequently, the MTF is limited predominantly by broadening within the thin phosphor underlayer. There are difficulties however, in the practical implementation of this design, associated mostly with the mechanical stability of the Al support film.

scholarly journals Metabolism of Epithelial Cells in Health and Allergic Disease: Collegium Internationale Allergologicum Update 2021

2021 ◽  
pp. 1-16
Author(s):  
Ashley M. Queener ◽  
Sergio E. Chiarella ◽  
Lyda Cuervo-Pardo ◽  
Mackenzie E. Coden ◽  
Hiam Abdala-Valencia ◽  
...  
Keyword(s):  
Allergic Disease ◽  
Clinical Evidence ◽  
Metabolic Diseases ◽  
Tricarboxylic Acid Cycle ◽  
Allergic Diseases ◽  
Atopic Disease ◽  
Airway Disease ◽  
Epithelial Barrier ◽  
Metabolic Dysfunction ◽  
New Research

Concomitant dramatic increase in prevalence of allergic and metabolic diseases is part of a modern epidemic afflicting technologically advanced societies. While clinical evidence points to clear associations between various metabolic factors and atopic disease, there is still a very limited understanding of the mechanisms that link the two. Dysregulation of central metabolism in metabolic syndrome, obesity, diabetes, and dyslipidemia has a systemic impact on multiple tissues and organs, including cells of the epithelial barrier. While much of epithelial research in allergy has focused on the immune-driven processes, a growing number of recent studies have begun to elucidate the role of metabolic components of disease. This review will revisit clinical evidence for the relationship between metabolic and allergic diseases, as well as discuss potential mechanisms driving metabolic dysfunction of the epithelial barrier. Among them, novel studies highlight links between dysregulation of the insulin pathway, glucose metabolism, and loss of epithelial differentiation in asthma. Studies of mitochondrial structure and bioenergetics in lean and obese asthmatic phenotypes recently came to light to provide a novel framework linking changes in tricarboxylic acid cycle and oxidative phosphorylation with arginine metabolism and nitric oxide bioavailability. New research established connections between arachidonate metabolism, autophagy, and airway disease, as well as systemic dyslipidemia in atopic dermatitis and ceramide changes in the epidermis. Taken together, studies of metabolism have a great potential to open doors to a new class of therapeutic strategies, better characterization of disease endotypes, as well as enable a systems biology approach to mechanisms of allergic disease.

scholarly journals Current Advances in the Biodegradation and Bioconversion of Polyethylene Terephthalate

2021 ◽  
Vol 10 (1) ◽  
pp. 39
Author(s):  
Xinhua Qi ◽  
Wenlong Yan ◽  
Zhibei Cao ◽  
Mingzhu Ding ◽  
Yingjin Yuan
Keyword(s):  
Polyethylene Terephthalate ◽  
Microbial Consortium ◽  
Tricarboxylic Acid Cycle ◽  
Tca Cycle ◽  
Tricarboxylic Acid ◽  
Microbial Consortia ◽  
Plastic Pollution ◽  
One Step ◽  
Complex Polymers ◽  
The One

Polyethylene terephthalate (PET) is a widely used plastic that is polymerized by terephthalic acid (TPA) and ethylene glycol (EG). In recent years, PET biodegradation and bioconversion have become important in solving environmental plastic pollution. More and more PET hydrolases have been discovered and modified, which mainly act on and degrade the ester bond of PET. The monomers, TPA and EG, can be further utilized by microorganisms, entering the tricarboxylic acid cycle (TCA cycle) or being converted into high value chemicals, and finally realizing the biodegradation and bioconversion of PET. Based on synthetic biology and metabolic engineering strategies, this review summarizes the current advances in the modified PET hydrolases, engineered microbial chassis in degrading PET, bioconversion pathways of PET monomers, and artificial microbial consortia in PET biodegradation and bioconversion. Artificial microbial consortium provides novel ideas for the biodegradation and bioconversion of PET or other complex polymers. It is helpful to realize the one-step bioconversion of PET into high value chemicals.

scholarly journals Embryonic development in Zungaro jahu

Zygote ◽  
2016 ◽  
Vol 25 (1) ◽  
pp. 17-31 ◽  
Author(s):  
Camila Marques ◽  
Francine Faustino ◽  
Bruno Bertolucci ◽  
Maria do Carmo Faria Paes ◽  
Regiane Cristina da Silva ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Embryonic Development ◽  
Egg Cell ◽  
Gastrula Stage ◽  
Transmission Electron ◽  
Larval Hatching ◽  
Morula Stage ◽  
Zygote Stage ◽  
Scanning Electron

SummaryThe aim of this study was to characterize the embryonic development of Zungaro jahu, a fresh water teleostei commonly known as ‘jaú’. Samples were collected at pre-determined times from oocyte release to larval hatching and analysed under light microscopy, transmission electron microscopy and scanning electron microscopy. At the first collection times, the oocytes and eggs were spherical and yellowish, with an evident micropyle. Embryo development took place at 29.4 ± 1.5°C and was divided into seven stages: zygote, cleavage, morula, blastula, gastrula, organogenesis, and hatching. The differentiation of the animal and vegetative poles occured during the zygote stage, at 10 min post-fertilization (mpf), leading to the development of the egg cell at 15 mpf. From 20 to 75 mpf, successive cleavages resulted in the formation of 2, 4, 8, 16, 32 and 64 blastomeres. The morula stage was observed between 90 and 105 mpf, and the blastula and gastrula stage at 120 and 180 mpf; respectively. The end of the gastrula stage was characterized by the presence of the yolk plug at 360 mpf. Organogenesis followed, with differentiation of the cephalic and caudal regions, elongation of the embryo by the cephalo-caudal axis, and somitogenesis. Hatching occurred at 780 mpf, with mean larval total length of 3.79 ± 0.11 mm.

scholarly journals Detection Limits of DLS and UV-Vis Spectroscopy in Characterization of Polydisperse Nanoparticles Colloids

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Emilia Tomaszewska ◽  
Katarzyna Soliwoda ◽  
Kinga Kadziola ◽  
Beata Tkacz-Szczesna ◽  
Grzegorz Celichowski ◽  
...  
Keyword(s):  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Point Of View ◽  
Spectroscopy Analysis ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
The One

Dynamic light scattering is a method that depends on the interaction of light with particles. This method can be used for measurements of narrow particle size distributions especially in the range of 2–500 nm. Sample polydispersity can distort the results, and we could not see the real populations of particles because big particles presented in the sample can screen smaller ones. Although the theory and mathematical basics of DLS technique are already well known, little has been done to determine its limits experimentally. The size and size distribution of artificially prepared polydisperse silver nanoparticles (NPs) colloids were studied using dynamic light scattering (DLS) and ultraviolet-visible (UV-Vis) spectroscopy. Polydisperse colloids were prepared based on the mixture of chemically synthesized monodisperse colloids well characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM), DLS, and UV-Vis spectroscopy. Analysis of the DLS results obtained for polydisperse colloids reveals that several percent of the volume content of bigger NPs could screen completely the presence of smaller ones. The presented results could be extremely important from nanoparticles metrology point of view and should help to understand experimental data especially for the one who works with DLS and/or UV-Vis only.

scholarly journals Ionic Liquids-Containing Silica Microcapsules: A Potential Tunable Platform for Shaping-Up Epoxy-Based Composite Materials?

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 881
Author(s):  
Ting Shi ◽  
Sébastien Livi ◽  
Jannick Duchet ◽  
Jean-François Gérard
Keyword(s):  
Electron Microscopy ◽  
Sol Gel ◽  
Diameter Distribution ◽  
Excellent Thermal Stability ◽  
Transmission Electron ◽  
Micron Size ◽  
Phosphonium Ionic Liquid ◽  
One Step ◽  
The One ◽  
First Time

In this work, silica microcapsules containing phosphonium ionic liquid (IL), denoted SiO2@IL, were successfully synthesized for the first time using the one step sol-gel method in IL/H20 emulsion. The morphologies of the obtained micron-size microcapsules, including their diameter distribution, were characterized using dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The thermal behavior of these microcapsules and the mass fraction of the encapsulated IL in the silica microcapsules were determined using thermogravimetric analysis, showing an excellent thermal stability (up to 220 °C) and highlighting that an amount of 20 wt.% of IL is contained in the silica microcapsules. In a second step, SiO2@IL microcapsules (1 wt.%) were dispersed into epoxy-amine networks to provide proof of concept of the ability of such microcapsules to act as healing agents as microcracks propagate into the epoxy networks.

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