A stereological study on organelle distribution in human oocytes at prophase I

Zygote ◽  
2015 ◽  
Vol 24 (3) ◽  
pp. 346-354 ◽  
Author(s):  
Ana Sílvia Pires-Luís ◽  
Eduardo Rocha ◽  
Carla Bartosch ◽  
Elsa Oliveira ◽  
Joaquina Silva ◽  
...  
Keyword(s):  
Zona Pellucida ◽  
Smooth Endoplasmic Reticulum ◽  
Molecular Data ◽  
Human Oocyte ◽  
Human Oocytes ◽  
Prophase I ◽  
Organelle Distribution ◽  
Transmission Electron ◽  
Maturation Stages

SummaryThe ultrastructural analysis of human oocytes at different maturation stages has only been descriptive. The aim of this study was to use a stereological approach to quantify the distribution of organelles in oocytes at prophase I (GV). Seven immature GV oocytes were processed for transmission electron microscopy and a classical manual stereological technique based on point-counting with an adequate stereological grid was used. The Kruskal–Wallis test and Mann–Whitney U-test with Bonferroni correction were used to compare the means of the relative volumes occupied by organelles in oocyte regions: cortex (C), subcortex (SC) and inner cytoplasm (IC). Here we first describe in GV oocytes very large vesicles of the smooth endoplasmic reticulum (SER), vesicles containing zona pellucida-like materials and coated vesicles. The most abundant organelles were the very large vesicles of the SER (6.9%), mitochondria (6.3%) and other SER vesicles (6.1%). Significant differences in organelle distribution were observed between ooplasm regions: cortical vesicles (C: 1.3% versus SC: 0.1%, IC: 0.1%, P = 0.001) and medium-sized vesicles containing zona pellucida-like materials (C: 0.2% versus SC: 0.02%, IC: 0%, P = 0.004) were mostly observed at the oocyte cortex, whereas mitochondria (C: 3.6% versus SC: 6.0%, IC: 7.2%, P = 0.005) were preferentially located in the subcortex and inner cytoplasm, and SER very large vesicles (IC: 10.1% versus C: 0.9%, SC: 1.67%, P = 0.001) in the oocyte inner cytoplasm. Further quantitative studies are needed in immature metaphase-I and mature metaphase-II oocytes, as well as analysis of correlations between ultrastructural and molecular data, to better understand human oocyte in vitro maturation.

scholarly journals Stereological Analysis of Mitochondria and Smooth Endoplasmic Reticulum Distribution in Human Oocytes at Prophase I

2008 ◽  
Vol 14 (S3) ◽  
pp. 103-104
Author(s):  
A. Luís ◽  
E. Rocha ◽  
E Oliveira ◽  
J. Silva ◽  
A. Barros ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Oocyte Maturation ◽  
Smooth Endoplasmic Reticulum ◽  
Germinal Vesicle ◽  
Human Oocytes ◽  
Stereological Analysis ◽  
Prophase I ◽  
Maturation Stages ◽  
In Vitro Oocyte Maturation

The structure of human oocytes at the different maturation stages is known based on descriptive studies of its ultrastructural composition. The tridimensional quantitative ultrastructural analysis of human oocytes would be important for understanding folliculogenesis and establishing adequate methods of in vitro oocyte maturation. In this study, stereological methods were applied to quantify the distribution of mitochondria (M) and smooth endoplasmic reticulum (SER) in oocytes at the germinal vesicle (VG) stage of prophase I.

scholarly journals Stereological study of organelle distribution in human oocytes at metaphase I

Zygote ◽  
2020 ◽  
Vol 28 (4) ◽  
pp. 308-317
Author(s):  
Sofia Coelho ◽  
Ana Sílvia Pires-Luís ◽  
Elsa Oliveira ◽  
Ângela Alves ◽  
Carla Leal ◽  
...  
Keyword(s):  
Smooth Endoplasmic Reticulum ◽  
Bonferroni Correction ◽  
Stereological Analysis ◽  
Molecular Approaches ◽  
Organelle Distribution ◽  
Transmission Electron ◽  
Metaphase Ii Oocytes ◽  
Metaphase I

SummaryWe have previously presented a stereological analysis of organelle distribution in human prophase I oocytes. In the present study, using a similar stereological approach, we quantified the distribution of organelles in human metaphase I (MI) oocytes also retrieved after ovarian stimulation. Five MI oocytes were processed for transmission electron microscopy and a classical manual stereological technique based on point-counting with an adequate stereological grid was used. Kruskal–Wallis and Mann–Whitney U-tests with Bonferroni correction were used to compare the means of relative volumes (Vv) occupied by organelles. In all oocyte regions, the most abundant organelles were mitochondria and smooth endoplasmic reticulum (SER) elements. No significant differences were observed in Vv of mitochondria, dictyosomes, lysosomes, or SER small and medium vesicles, tubular aggregates and tubules. Significant differences were observed in other organelle distributions: cortical vesicles presented a higher Vv (P = 0.004) in the cortex than in the subcortex (0.96% vs 0.1%) or inner cytoplasm (0.96% vs 0.1%), vesicles with dense granular contents had a higher Vv (P = 0.005) in the cortex than in the subcortex (0.1% vs 0%), and SER large vesicles exhibited a higher Vv (P = 0.011) in the inner cytoplasm than in the subcortex (0.2% vs 0%). Future stereological analysis of metaphase II oocytes and a combined quantitative data of mature and immature oocytes, will enable a better understanding of oocyte organelle distribution during in vivo maturation. Combined with molecular approaches, this may help improve stimulation protocols and in vitro maturation methods.

scholarly journals Dysfunction of Low-Density Neutrophils in Peripheral Circulation in Patients With Sepsis

2021 ◽  
Author(s):  
Ran Sun ◽  
Jiamin Huang ◽  
Yunxi Yang ◽  
Lu Liu ◽  
Yiming Shao ◽  
...  
Keyword(s):  
Morphological Characteristics ◽  
Peripheral Circulation ◽  
Low Density ◽  
Transmission Electron ◽  
Essential Components ◽  
Neutrophil Degranulation ◽  
Maturation Stages ◽  
And Function ◽  
Chemokine Receptor 4

Abstract Background Low-density neutrophils (LDNs) have been described in tumors and various autoimmune diseases, where they exhibit immune dysfunction and alter disease progression. Nevertheless, LDNs have been rarely reported in sepsis. Methods We studied sepsis patients admitted to the intensive care unit. WrightGiemsa stain assay and Transmission electron microscopy were performed to detect the morphology of neutrophils. Flow cytometry was used to analyze the number and function of LDNs. Concentration of cytokines was measured using ELISA. Neutrophil chemotaxis was examined using an under-agarose chemotaxis model. Results We found that LDNs were significantly elevated in patients with sepsis. Phenotypes and morphological characteristics suggest that LDNs may be formed by mixtures of neutrophils at various maturation stages. In vitro experiments showed that LDN formation was closely associated with neutrophil degranulation. We preliminarily discussed changes in immune function in LDNs. Compared with high-density neutrophils, expression levels of CXC chemokine receptor 4 on LDN surfaces were increased, phagocytotic capacity was decreased, and life span was prolonged. The chemotactic ability of LDNs was significantly reduced, possibly related to the increased expression of P2X1. Conclusions These data suggest that LDNs are essential components of neutrophils in sepsis. To clarify the source and dysfunction mechanism of LDN in sepsis may be helpful for the diagnosis and treatment of sepsis in the future.

Human oocyte cytometry and fertilisation rate after subzonal insemination

Zygote ◽  
1995 ◽  
Vol 3 (2) ◽  
pp. 101-109 ◽  
Author(s):  
Jean Philippe Wolf ◽  
Sylvie Bulwa ◽  
Daniel Rodrigues ◽  
Pierre Jouannet
Keyword(s):  
Zona Pellucida ◽  
Human Oocyte ◽  
Oocyte Diameter ◽  
Antisperm Antibodies ◽  
Subzonal Insemination ◽  
Fertilisation Rate ◽  
Defect Groups ◽  
The Mean ◽  
Dynein Arms

SummaryThe cytometry of 545 oocytes was evaluated during subzonal insemination (SUZI; 85 attempts), on day 0 (egg retrieval and SUZI), day 1 and day 2(embryo transfer). On day 0, the egg and oolemma diameters (mean ± SD) were 164.0 ± 19.6 μm and 114.2±16.8 μ5m respectively.The zona thickness was 17.8± 13.4 μm and correlated with the oolemma diameter(r = 0.24, p < 0.001). The fertilisation rate was significantly lower for the smaller oocytes (less than 108 μm diameter) compared with the larger oocytes (over 108μm) (9.8% vs 21.2% respectively; p < 0.05). These was little variation in oocyte diameter according to nuclear status. However, oocyte diameter increased significantly between day 0 and day 1 (p < 0.001) for both fertilised and unfertilised oocytes. Six different indications for SUZI were investigated in detail: three with non-specific (normal and subnormal sperm with in vitro fertilization failure, oligoasthenospermia) and three with specific sperm defects (flagellar dyskinesia, absence of outer dynein arms, antisperm antibodies). Oocytes from the non-specific defect groups had significantly smaller diameters than the others (p < 0.05). The mean fertilisation rate was related to the mean oolemma diameter for the groups with non-specific sperm defects and the group lacking dynein arms (LODA) (r = 0.91, p < 0.05). Eggs from the groups of patients with LODA and those with antisperm antibodies had thicker zona pellucida than others (p < 0.05). These findings suggest that in addition to nuclear criteria of maturity, the growth of oocytes is an important factor for fertilising ability. Insufficient development of the ooplasm may contribute to fertilisation failure, particularly when sperm with functional defects are used. In contrast, a thick zona pellucida may prevent sperm with specific anomalies such as LODA or antisperm antibodies from penetrating into the perivitelline space.

Zona pellucida birefringence and meiotic spindle visualisation of human oocytes are not influenced by IVM technology

2014 ◽  
Vol 26 (3) ◽  
pp. 407 ◽  
Author(s):  
Marjan Omidi ◽  
Mohammad Ali Khalili ◽  
Sareh Ashourzadeh ◽  
Marzieh Rahimipour
Keyword(s):  
Zona Pellucida ◽  
Polar Body ◽  
Refractile Body ◽  
Meiotic Spindle ◽  
Human Oocytes ◽  
Non Invasive ◽  
Safe Technology ◽  
Maturation Rate

The aim of the present study was to investigate the relationship between the presence of the meiotic spindle and zona pellucida (ZP) birefringence with morphology of in vivo- and in vitro-matured human oocytes. Germinal vesicles (n = 47) and MI (n = 38) oocytes obtained from stimulated ovaries of patients undergoing intracytoplasmic sperm injection (ICSI) underwent IVM. Using a PolScope (OCTAX PolarAID; Octax, Herbon, Germany), the presence of spindles and ZP birefringence was assessed in both in vivo-matured (n = 56) and IVM (n = 56) oocytes. In addition, the morphology of each matured oocyte was evaluated microscopically. There were insignificant differences for ZP birefringence and meiotic spindle between the in vivo-matured and IVM MII oocytes. Subanalysis revealed that the rates of morphologically abnormal oocytes did not differ significantly between the two groups, except in the case of irregular shape (P = 0.001), refractile body (P = 0.001) and fragmented polar body (P = 0.03), which were higher in IVM oocytes. In the case of in vivo-matured oocytes, a significantly higher percentage of oocytes with intracytoplasmic and both intra- and extracytoplasmic abnormalities have a low birefringent ZP (P = 0.007 and P = 0.02, respectively). There was no relationship between morphological abnormalities and spindle detection. The findings suggest that clinical IVM is a safe technology that maintains the high maturation rate and integrity of oocytes. In addition, the use of the non-invasive PolScope is recommended for the detection of oocytes most suitable for ICSI.

scholarly journals Effects of Vitrification on Outcomes of In VivoMature, In Vitro-Mature and Immature Human Oocytes

2016 ◽  
Vol 38 (5) ◽  
pp. 2053-2062 ◽  
Author(s):  
Wen-yan Song ◽  
Zhao-feng Peng ◽  
Xue-mei Chen ◽  
Hai-xia Jin ◽  
Gui-dong Yao ◽  
...  
Keyword(s):  
Zona Pellucida ◽  
Occurrence Rate ◽  
Aneuploidy Screening ◽  
Immature Oocytes ◽  
Human Oocytes ◽  
Group A ◽  
Mature Group ◽  
Group B

Background/Aims: To observe the effects of vitrification on spindle, zona pellucida, embryonic aneuploidy and DNA injury in in vivo-maruted, in vitro-mature and immature human oocytes. Methods: Between January 2009 and February 2015, 223 immature oocytes from 450 infertile patients, and 31 in vivo-mature oocytes from 3 infertile couples were collected. Of the 223 immature oocytes, 113 were used for in vitro culture before vitrification. Some oocytes were randomly divided into in vivo-mature group (group A, n = 15), in vitro-mature group (group B, n = 88) and immature group (group C, n = 85), and then the oocytes with spindle in these three groups after freezing-thawing were selected to use for Polscope imaging, embryonic aneuploidy screening and embryo development evaluation. Other oocytes were randomly divided into group A (n = 16), group B (n = 25) and group C (n = 25) for detecting DNA injury. Results: After thawing, spindle occurrence rate, spindle Retardance value, and cleavage rate were significantly higher in groups A and B than in group C (all P < 0.05), but there were no statistical differences in fertility rate, high-quality embryo rate, blastulation rate and aneuploidy rate amongst the three groups (all P > 0.05). Zona pellucida density (ZPD) was significantly lower in group A than in groups B and C both before and after vitrification (all P < 0.05). ZPD was significantly higher after thawing than before vitrification (all P < 0.05), but zona pellucida thickness (ZPT) was not significantly changed in all the three groups (all P > 0.05). Rate of comet cells was significantly lower in group A than in groups B and C (all P < 0.01). Comet tail was significantly longer in group C than in groups B and A (all P < 0.05). Conclusion: In vivo- and in vitro-mature human oocytes are more suitable to vitrification than immature human oocytes. Spindle Retardance value has more predictive value for embryonic development potential than ZPD and ZPT.

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