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"Schuring, Martin"
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Africa’s wooden elephant: the baobab tree (Adansonia digitata L.) in Sudan and Kenya: a review
Wild edible fruits hold great potential for improving human diets, especially in agricultural societies of the developing world. In Africa, a well-known supplier of such fruits is the baobab (
Adansonia digitata
L., Malvaceae), one of the most remarkable trees of the world. Several studies in different African countries have highlighted this indigenous fruit tree as a priority species for domestication and expanded use. However, internationally available information on baobab in East Africa, particularly in Sudan and Kenya, remains scarce. This review aims to shed light on the ecology, diversity and current level of utilization of baobab in East Africa in order to facilitate domestication and conservation of the species. A list of priority research areas is provided at the end of the review to encourage further studies and investment in this unique plant taxon.
Journal Article
Origin and clinical relevance of chromosomal aberrations other than the common trisomies detected by genome-wide NIPS: results of the TRIDENT study
Purpose
Noninvasive prenatal screening (NIPS) using cell-free DNA in maternal blood is highly sensitive for detecting fetal trisomies 21, 18, and 13. Using a genome-wide approach, other chromosome anomalies can also be detected. We report on the origin, frequency, and clinical significance of these other chromosome aberrations found in pregnancies at risk for trisomy 21, 18, or 13.
Methods
Whole-genome shallow massively parallel sequencing was used and all autosomes were analyzed.
Results
In 78 of 2,527 cases (3.1%) NIPS was indicative of trisomy 21, 18, or 13, and in 41 (1.6%) of other chromosome aberrations. The latter were of fetal (
n
= 10), placental (
n
= 22), maternal (
n
= 1) or unknown (
n
= 7). One case lacked cytogenetic follow-up. Nine of the 10 fetal cases were associated with an abnormal phenotype. Thirteen of the 22 (59%) placental aberrations were associated with fetal congenital anomalies and/or poor fetal growth (
Journal Article
Discordant NIPT result in a viable trisomy‐21 pregnancy due to prolonged contribution to cfDNA by a demised trisomy‐14 cotwin
Key Clinical Message One of the confounders in noninvasive prenatal testing (NIPT) is the vanishing twin phenomenon. Prolonged contribution to the maternal Cell‐free DNA (cfDNA) pool by cytotrophoblasts representing a demised, aneuploid cotwin may lead to a false‐positive outcome for a normal, viable twin. We show that a vanishing trisomy‐14 twin contributes to cfDNA for more than 2 weeks after demise. One of the confounders in noninvasive prenatal testing (NIPT) is the vanishing twin phenomenon. Prolonged contribution to the maternal Cell‐free DNA (cfDNA) pool by cytotrophoblasts representing a demised, aneuploid cotwin may lead to a false‐positive outcome for a normal, viable twin. We show that a vanishing trisomy‐14 twin contributes to cfDNA for more than 2 weeks after demise.
Journal Article
Cell‐free fetal DNA in the maternal circulation originates from the cytotrophoblast: proof from an unique case
Key Clinical Message Noninvasive prenatal testing (NIPT) and direct karyotyping of cytotrophoblast were normal for a male fetus, but cultured chorionic villus mesenchymal cells and umbilical cord fibroblasts showed nonmosaic trisomy 18. This observation provides direct evidence for the cytotrophoblastic origin of cell‐free fetal DNA and yields a biological explanation for falsely reassuring NIPT results. Noninvasive prenatal testing (NIPT) and direct karyotyping of cytotrophoblast were normal for a male fetus, but cultured chorionic villus mesenchymal cells and umbilical cord fibroblasts showed nonmosaic trisomy 18. This observation provides direct evidence for the cytotrophoblastic origin of cell‐free fetal DNA and yields a biological explanation for falsely reassuring NIPT results.
Journal Article
Characterization of E-Cadherin, SSEA-1, MSI-1, and SOX-2 Expression and Their Association with Pale Cells in Adenomyosis
Adenomyosis (AM) is a gynecological disease characterized by the invasion of endometrial glands and stroma within the myometrium. The etiology and pathogenesis of AM remain inadequately understood. Pale cells were identified as a novel cell type characterized by the absence of desmosomal contacts and light-colored cytoplasm. These cells were observed to migrate individually through ultra-micro ruptures in the basal membrane of the endometrial glands, translocating into the stroma and then further into the myometrium. Our study aimed to explore the possible stem cell properties of these pale cells. Forty hysterectomy specimens were analyzed using immunohistochemistry and immunofluorescence to assess negative E-cadherin expression and the positive expression of stem cell markers SSEA-1, MSI-1, and SOX-2. Immunohistochemical analysis revealed the presence of pale cells and occasionally rounded, enlarged E-cadherin-negative cells predominantly in the basal endometrial epithelium. The stem cell marker SSEA-1 was significantly elevated in the basalis epithelium, as well as in the ectopic epithelium. SSEA-1 positive cells were also identified in the stroma and myometrium. Sporadic colocalization of SSEA-1+/E-cadherin– cells was confirmed through immunofluorescence. The positive staining of pale cells for SSEA-1 and MSI-1 was also confirmed at the ultrastructural level by immunoelectron microscopy. These findings indicate that pale cells may possess stem cell characteristics, particularly a positive SSEA-1 profile, warranting further in vitro investigation into their role in the pathogenesis of adenomyosis.
Journal Article
Discordant NIPT result in a viable trisomy‐21 pregnancy due to prolonged contribution to cf DNA by a demised trisomy‐14 cotwin
One of the confounders in noninvasive prenatal testing ( NIPT ) is the vanishing twin phenomenon. Prolonged contribution to the maternal Cell‐free DNA (cf DNA ) pool by cytotrophoblasts representing a demised, aneuploid cotwin may lead to a false‐positive outcome for a normal, viable twin. We show that a vanishing trisomy‐14 twin contributes to cf DNA for more than 2 weeks after demise.
Journal Article
The Action of Reproductive Fluids and Contained Steroids, Prostaglandins, and Zn2+ on CatSper Ca2+ Channels in Human Sperm
The sperm-specific Ca 2+ channel CatSper registers chemical cues that assist human sperm to fertilize the egg. Prime examples are progesterone and prostaglandin E 1 that activate CatSper without involving classical nuclear and G protein-coupled receptors, respectively. Here, we study the action of seminal and follicular fluid as well of the contained individual prostaglandins and steroids on the intracellular Ca 2+ concentration of sperm from donors and CATSPER2 -deficient patients that lack functional CatSper channels. We show that any of the reproductive steroids and prostaglandins evokes a rapid Ca 2+ increase that invariably rests on Ca 2+ influx via CatSper. The hormones compete for the same steroid- and prostaglandin-binding site to activate the channel, respectively. Analysis of the hormones’ structure–activity relationship highlights their unique pharmacology in sperm and the chemical features determining their effective properties. Finally, we show that Zn 2+ suppresses the action of steroids and prostaglandins on CatSper, which might prevent premature prostaglandin activation of CatSper in the ejaculate, aiding sperm to escape from the ejaculate into the female genital tract. Altogether, our findings reinforce that human CatSper serves as a promiscuous chemosensor that enables sperm to probe the varying hormonal microenvironment prevailing at different stages during their journey across the female genital tract.
Journal Article
Arrangement of myofibroblastic and smooth muscle-like cells in superficial peritoneal endometriosis and a possible role of transforming growth factor beta 1 (TGFβ1) in myofibroblastic metaplasia
Purpose
Superficial peritoneal endometriotic (pEM) lesions are composed of endometrial glands and stroma, in addition to a third component—myofibroblasts and smooth muscles (SM)-like cells. The latter develops secondary to a metaplasia. In this study, we characterised the third component cells in pEM according to differentiation markers in different micro-compartments. Furthermore, a possible effect of TGFβ1 on myofibroblastic metaplasia in endometriotic epithelial cells was studied.
Methods
Seventy-six premenopausal patients were included. Peritoneal biopsies were excised from EM patients (
n
= 23), unaffected peritoneum (peritoneum from EM patients but without EM components,
n
= 5/23) and non-EM patients (
n
= 10). All peritoneal biopsies were immunolabeled for ASMA, calponin, collagen I, desmin, TGFß receptor 1 (R1), R2 and R3 in addition to ultrastructure examination by transmission electron microscopy (TEM) (
n
= 1). TGFß1 level was measured in peritoneal fluid (PF) (EM,
n
= 19 and non-EM,
n
= 13) collected during laparoscopy. Furthermore, TGFß1 effect on myofibroblastic metaplasia was studied in vitro.
Results
At the centre of pEM lesions, calponin immunolabeling outweighs the collagen I while in the periphery the reverse occurs. SM-like cells expressing desmin predominate at the periphery, while ASMA immunolabeling was detectable in all micro-compartments. Both indicate an abundance of myofibroblasts at the centre of pEM lesions and SM-like cells in the periphery. Although activated TGFß1 in PF did not differ between EM and non-EM, it inhibited the cell proliferation of the endometriotic epithelial cells and induced an upregulation in ASMA and collagen IA2 expression as well.
Conclusion
The abundance of the myofibroblasts and SM-like cells points to a myofibroblastic metaplasia in pEM. Both cells are differentially arranged in the different micro-compartments of pEM lesions, with increasing cell maturity towards the periphery of the lesion. Furthermore, TGFß1 may play a role in the myofibroblastic metaplasia of the endometriotic epithelial cells. These findings provide a better insight in the micro-milieu in EM lesions, where most of the disease dynamics occur.
Journal Article
Role of syndecan-3 polymorphisms in obesity and female hyperandrogenism
The heparan sulfate proteoglycan syndecan-3 (
SDC3
) is a novel regulator of feeding behavior and body weight. Recently, an association of
SDC3
polymorphisms with obesity has been observed in Koreans. As female obesity is associated with hyperandrogenism and infertility, we studied the role of
SDC3
polymorphisms in female individuals undergoing diagnostics prior to infertility treatment. For this purpose, endocrine parameters and body mass index of 249 women were assessed. Genotyping of V208I, D303N, and T329I was performed with TaqMan technology using lymphocyte-derived DNA and allelic discrimination polymerase chain reaction. Chi-square test, Student’s
t
test, and one-way analysis of variance were used for statistical analysis. We find that an infrequent genotype and allele variation of T329I correlated with obesity (
p
= 0.028). Genotype and alleles of V208I were associated with luteinizing hormone (
p
= 0.007 and
p
= 0.001, respectively), luteinizing hormone/follicle-stimulating hormone (
p
= 0.002 and
p
< 0.005, respectively), 17 hydroxyprogesterone (
p
= 0.007 and
p
= 0.001, respectively), androstenedione (
p
= 0.046 and
p
= 0.013, respectively), and sex hormone-binding globulin (
p
= 0.021). We conclude that marked ethnic differences of the
SDC3
SNP distribution in our European population could account for correlations less predominant compared to Koreans. While infrequent variations of T329I correlated with obesity, V208I was associated with endocrine parameters related to hyperandrogenism. These findings indicate that
SDC3
polymorphisms could contribute to the link between female hyperandrogenism and obesity and suggest a novel potential role for
SDC3
as a modulator of gonadal steroid function.
Journal Article