Olga Malysheva

Dr. Olga Malysheva

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
Verified
Journal Article
Open access
PDF file
VBVladislav BARANOV
Vladislav BARANOV
OMOlga Malysheva
Olga Malysheva
MYMaria Yarmolinskaya
Maria Yarmolinskaya
For over 100 years, endometriosis, as a chronic, estrogen-dependent, inflammatory, heritable disease affecting approximately 5–10% of women in reproductive age has been the focus of clinicians and scientists. In spite of numerous environmental, genetic, epigenetic, endocrine, and immunological studies, our knowledge of endometriosis is still fragmentary, and its precise pathophysiology and pathogenomics remain a mystery. The implementation of new technologies has provided tremendous progress in understanding the many intrinsic molecular mechanisms in the development of endometriosis, with progenitor and stem cells (SCs) of the eutopic endometrium as the starting players and endometriotic lesions as the final pathomorphological trait. Novel data on the molecular, genetic, and epigenetic mechanisms of the disease are briefly outlined. We hypothesize the existence of an endometriosis development genetic program (EMDP) that governs the origin of endometrium stem cells programmed for endometriosis (1), their transition (metaplasia) into mesenchymal SCs (2), and their invasion of the peritoneum and progression to endometriotic lesions (3). The pros and cons of the recent unifying theory of endometriosis are also discussed. Complex genomic and epigenetic interactions at different stages of the endometriosis process result in different forms of the disease, with specific features and clinical manifestations. The significance of the EMDP in elaborating a new strategy for endometriosis prediction, prevention, and treatment is discussed.

26 April 2022 in JDS Communications
Verified
Journal Article
Open access
TSTurner H. Swartz
Turner H. Swartz
BBB.J. Bradford
B.J. Bradford
OMOlga Malysheva
Olga Malysheva
MCMarie A. Caudill
Marie A. Caudill
LML.K. Mamedova
L.K. Mamedova
KEKari Estes
Kari Estes
Summary: We assessed the effects of dietary choline supplementation on colostrum yields, quality, and choline metabolites from dairy cattle. Dietary choline supplementation increased the amount of colostrum produced without affecting the concentration of antibodies. Furthermore, dietary choline supplementation enhanced phosphocholine concentrations in colostrum from cows calving for the second time but had no effect on phosphocholine concentrations in colostrum from older cows. Finally, dietary choline supplementation increased concentrations of trimethylamine N-oxide, which is a choline metabolite derived from gut microbial metabolism.

1 October 2019 in The Journal of Nutritional Biochemistry
Verified
Journal Article
Closed access
JKJulia King
Julia King
SKSze Ting (Cecilia) Kwan
Sze Ting (Cecilia) Kwan
SBSajin Bae
Sajin Bae
KKKevin C Klatt
Kevin C Klatt
JYJian Yan
Jian Yan
MCMarie A. Caudill
Marie A. Caudill

26 November 2021 in Biomedicines
Verified
Journal Article
Open access
PDF file
AKAlla S. Koltsova
Alla S. Koltsova
OEOlga Efimova
Olga Efimova
OMOlga Malysheva
Olga Malysheva
NONatalia Osinovskaya
Natalia Osinovskaya
Thomas LiehrThomas Liehr
Thomas Liehr
APAnna Pendina
Anna Pendina
We performed a comparative cytogenomic analysis of cultured and uncultured uterine leiomyoma (UL) samples. The experimental approach included karyotyping, aCGH, verification of the detected chromosomal abnormalities by metaphase and interphase FISH, MED12 mutation analysis and telomere measurement by Q-FISH. An abnormal karyotype was detected in 12 out of 32 cultured UL samples. In five karyotypically abnormal ULs, MED12 mutations were found. The chromosomal abnormalities in ULs were present mostly by complex rearrangements, including chromothripsis. In both karyotypically normal and abnormal ULs, telomeres were ~40% shorter than in the corresponding myometrium, being possibly prerequisite to chromosomal rearrangements. The uncultured samples of six karyotypically abnormal ULs were checked for the detected chromosomal abnormalities through interphase FISH with individually designed DNA probe sets. All chromosomal abnormalities detected in cultured ULs were found in corresponding uncultured samples. In all tumors, clonal spectra were present by the karyotypically abnormal cell clone/clones which coexisted with karyotypically normal ones, suggesting that chromosomal abnormalities acted as drivers, rather than triggers, of the neoplastic process. In vitro propagation did not cause any changes in the spectrum of the cell clones, but altered their ratio compared to uncultured sample. The alterations were unique for every UL. Compared to its uncultured counterpart, the frequency of chromosomally abnormal cells in the cultured sample was higher in some ULs and lower in others. To summarize, ULs are characterized by both inter- and intratumor genetic heterogeneity. Regardless of its MED12 status, a tumor may be comprised of clones with and without chromosomal abnormalities. In contrast to the clonal spectrum, which is unique and constant for each UL, the clonal frequency demonstrates up or down shifts under in vitro conditions, most probably determined by the unequal ability of cells with different genetic aberrations to exist outside the body.

14 April 2023 in Genes
Verified
Journal Article
Open access
PDF file
OTOlga E. Talantova
Olga E. Talantova
AKAlla S. Koltsova
Alla S. Koltsova
TATikhonov V. Andrei
Tikhonov V. Andrei
APAnna Pendina
Anna Pendina
OMOlga Malysheva
Olga Malysheva
OEOlga Efimova
Olga Efimova
We report on the case of prenatal detection of trisomy 2 in placental biopsy and further algorithm of genetic counseling and testing. A 29-year-old woman with first-trimester biochemical markers refused chorionic villus sampling and preferred targeted non-invasive prenatal testing (NIPT), which showed low risk for aneuploidies 13, 18, 21, and X. A series of ultrasound examinations revealed increased chorion thickness at 13/14 weeks of gestation and fetal growth retardation, a hyperechoic bowel, challenging visualization of the kidneys, dolichocephaly, ventriculomegaly, increase in placental thickness, and pronounced oligohydramnios at 16/17 weeks of gestation. The patient was referred to our center for an invasive prenatal diagnosis. The patient’s blood and placenta were sampled for whole-genome sequencing-based NIPT and array comparative genomic hybridization (aCGH), respectively. Both investigations revealed trisomy 2. Further prenatal genetic testing in order to confirm trisomy 2 in amniocytes and/or fetal blood was highly questionable because oligohydramnios and fetal growth retardation made amniocentesis and cordocentesis technically unfeasible. The patient opted to terminate the pregnancy. Pathological examination of the fetus revealed internal hydrocephalus, atrophy of brain structure, and craniofacial dysmorphism. Conventional cytogenetic analysis and fluorescence in situ hybridization revealed chromosome 2 mosaicism with a prevalence of trisomic clone in the placenta (83.2% vs. 16.8%) and a low frequency of trisomy 2, which did not exceed 0.6% in fetal tissues, advocating for low-level true fetal mosaicism. To conclude, in pregnancies at risk of fetal chromosomal abnormalities that refuse invasive prenatal diagnosis, whole-genome sequencing-based NIPT, but not targeted NIPT, should be considered. In prenatal cases of trisomy 2, true mosaicism should be distinguished from placental-confined mosaicism using cytogenetic analysis of amniotic fluid cells or fetal blood cells. However, if material sampling is impossible due to oligohydramnios and/or fetal growth retardation, further decisions should be based on a series of high-resolution fetal ultrasound examinations. Genetic counseling for the risk of uniparental disomy in a fetus is also required.

Verified
Journal Article
Open access
PDF file
TATikhonov V. Andrei
Tikhonov V. Andrei
MKMikhail Krapivin
Mikhail Krapivin
OMOlga Malysheva
Olga Malysheva
EKEvgeniia M. Komarova
Evgeniia M. Komarova
AGArina Golubeva
Arina Golubeva
APAnna Pendina
Anna Pendina
Background: In recent years, preimplantation genetic testing for aneuploidies (PGT-A) has become widespread in assisted reproduction. However, contrary to expectations, PGT-A does not significantly improve the clinical outcomes of assisted reproductive technologies. One of the underlying reasons is the discordance between the PGT-A results and the true chromosomal constitution of the blastocyst. In this case series, we re-examined the PGT-A results in trophectoderm (TE) re-biopsies and in the two isolated blastocyst compartments—the TE and the inner cell mass (ICM). Methods: This study enrolled 23 human blastocysts from 17 couples who were referred for assisted reproduction. The blastocysts were unsuitable for uterine transfer due to the chromosomal imbalance revealed by PGT-A using array comparative genomic hybridization (aCGH) (n = 11) or next-generation sequencing (NGS) (n = 12). The re-examination of the PGT results involved two steps: (1) a TE re-biopsy with subsequent aCGH and (2) blastocyst separation into the TE and the ICM with a subsequent cell-by-cell analysis of each isolated compartment by fluorescence in situ hybridization (FISH) with the DNA probes to chromosomes 13, 16, 18, 21, and 22 as well as to the PGT-A detected imbalanced chromosomes. Results: In 8 out of 23 cases, the PGT-A results were concordant with both the re-biopsy and the isolated TE and ICM analyses. The latter included the diagnoses of full non-mosaic aneuploidies (five cases of trisomies and two cases of monosomies). In one case, the results of PGT-A, aCGH on the TE re-biopsy, and FISH on the isolated TE showed Xp tetrasomy, which contrasted with the FISH results on the isolated ICM, where this chromosomal pathology was not detected. This case was classified as a confined mosaicism. In 4 out of 23 cases, the results were partially discordant. The latter included one case of trisomy 12, which was detected as non-mosaic by PGT-A and the re-biopsy and as mosaic by FISH on the isolated TE and ICM. This case was classified as a true mosaicism with a false negative PGT-A result. In 11 out of 23 cases, the re-examination results were not concordant with the PGT-A results. In one of these discordant cases, non-mosaic tetraploidy was detected by FISH in the isolated TE and ICM, whereas the PGT-A and the TE re-biopsy failed to detect any abnormality, which advocated for their false negative result. In two cases, the re-examination did not confirm full aneuploidies. In eight cases, full or partial mosaic aneuploidies as well as chaotic mosacism were not confirmed in the isolated TE nor the isolated ICM. Thus, in 47.8% of cases, the PGT-A results did not reflect the true chromosomal constitution of a blastocyst. Conclusions: The PGT results may have different prognostic value in the characterization of the chromosomal constitution of a blastocyst. The detected non-mosaic aneuploidies have the highest prognostic value. In stark contrast, most PGT-identified mosaic aneuploidies fail to characterize the true chromosomal constitution of a blastocyst. Once detected, a differential diagnosis is needed.