Embryonic Layers Research Articles

The Mellowed Trinitarian Mature Teratoma Ovary: A Short Communication

Mature teratoma is a frequently discerned, benign, ovarian germ cell neoplasm comprised of mature tissue manifesting two or three embryonic layers as ectoderm, mesoderm or endoderm. Additionally designated as mature cystic teratoma, mature solid teratoma or dermoid cyst, mature tissue minimally emerging from two embryonic layers is necessitated for cogent disease discernment. Malignant metamorphosis may ensue wherein prognostic outcomes are contingent to subtype of malignancy. Mature teratoma commonly occurs within reproductive age group. An estimated 10% neoplasms are bilateral. Mature teratoma is a diploid tumour and enunciates a normal, 46XX karyotype [1,2].

Hyperemesis Gravidarum and the Potential for Cancer: A Longitudinal Cohort Study over Three Decades.

Our objective was to assess whether hyperemesis gravidarum is associated with the risk of endodermal, mesodermal, and ectodermal human chorionic gonadotropin (hCG) receptor+ cancer in women. We performed a longitudinal cohort study of 1,343,040 women who were pregnant between 1989 and 2019 in Quebec, Canada. We identified women with and without hyperemesis gravidarum and followed them over time to capture incident cancers, grouped by embryonic germ cell layer of origin and organ hCG receptor positivity. We used time-varying Cox regression to model hazard ratios (HR) and 95% confidence intervals (CI) for the association between hyperemesis gravidarum and cancer onset, adjusted for maternal age, comorbidity, multiple gestation, fetal congenital anomaly, socioeconomic deprivation, and time period. Women with hyperemesis gravidarum had a greater risk of endodermal cancer compared with no hyperemesis gravidarum (5.8 vs. 4.8 per 10,000 person-years; HR, 1.36; 95% CI, 1.17-1.57), but not mesodermal or ectodermal cancer. Severe hyperemesis with metabolic disturbance was more strongly associated with cancer from the endodermal germ layer (HR, 1.97; 95% CI, 1.51-2.58). The association between hyperemesis gravidarum and endodermal cancer was driven by bladder (HR, 2.49; 95% CI, 1.37-4.53), colorectal (HR, 1.41; 95% CI, 1.08-1.84), and thyroid (HR, 1.43; 95% CI, 1.09-1.64) cancer. Women with hyperemesis gravidarum have an increased risk of cancers arising from the endodermal germ cell layer, particularly bladder, colorectal, and thyroid cancers. Future studies identifying the pathways linking hyperemesis gravidarum with endodermal tumors may help improve the detection and management of cancer in women.

How Widespread Are the "Young" Neurons of the Mammalian Brain?

After the discovery of adult neurogenesis (stem cell-driven production of new neuronal elements), it is conceivable to find young, undifferentiated neurons mixed with mature neurons in the neural networks of the adult mammalian brain. This “canonical” neurogenesis is restricted to small stem cell niches persisting from embryonic germinal layers, yet, the genesis of new neurons has also been reported in various parenchymal brain regions. Whichever the process involved, several populations of “young” neurons can be found at different locations of the brain. Across the years, further complexity emerged: (i) molecules of immaturity can also be expressed by non-dividing cells born during embryogenesis, then maintaining immature features later on; (ii) remarkable interspecies differences exist concerning the types, location, amount of undifferentiated neurons; (iii) re-expression of immaturity can occur in aging (dematuration). These twists are introducing a somewhat different definition of neurogenesis than normally assumed, in which our knowledge of the “young” neurons is less sharp. In this emerging complexity, there is a need for complete mapping of the different “types” of young neurons, considering their role in postnatal development, plasticity, functioning, and interspecies differences. Several important aspects are at stake: the possible role(s) that the young neurons may play in maintaining brain efficiency and in prevention/repair of neurological disorders; nonetheless, the correct translation of results obtained from laboratory rodents. Hence, the open question is: how many types of undifferentiated neurons do exist in the brain, and how widespread are they?

Mature ruptured sacrococcygeal teratoma in a 1-day old neonate

Sacrococcygeal teratomas (SCTs) are rare congenital tumors that are derived from embryonic germ cell layers [1]. They are the most common extragonadal germ cell tumors (GCTs) in the neonate, with a reported incidence of 1 in 35 000 births [2]. Teratomas are made of tissues that derive from three germinal layers (ectoderm, endoderm, and mesoderm). Sacrococcygeal teratomas are more common in girls, with a sex ratio of 1:4 [3]. The most frequent location of teratoma in children is the sacrococcygeal area [4]. Many sacrococcygeal teratoma cases are diagnosed prenatally with routine ultrasonography between the 22nd and the 34th week of gestation. However, access to routine prenatal ultrasound in low and middle income countries is limited [5]. Antenatal diagnosis is essential to the pregnancy management and to prevent neonatal death by identifying fetuses that are at a higher risk of complications and planning an adequate intervention when needed [6]. This case is reported to describe a North African neonate presenting with a sacrococcygeal teratoma at birth without prior antenatal diagnosis, and highlight the need for prenatal routine care in low and middle income countries.

Stem cell-based region-specific brain organoids: Novel models to understand neurodevelopmental defects.

The study of human brain development and neurodevelopmental defects has remained challenging so far due to unique, specific, and complex underlying processes. Recent advances in the technologies and protocols of in vitro human brain organoid development have led to immense possibilities of understanding these processes. Human brain organoids are stem-cell derived three-dimensional in vitro tissues that resemble the developing fetal brain. Major advances in stem cell techniques pioneering the development of in vitro human brain development include reprogramming human somatic cells into induced pluripotent cells (iPSCs) followed by the targeted differentiation of iPSCs into the cells of three embryonic germ cell layers. The neural progenitor cells produced by the directed differentiation of iPSCs undergo some level of self-organization to generate in vitro human brain like tissue. A three-dimensional differentiation approach applied to create region-specific brain organoids has successfully led to develop highly specialized cortical, forebrain, pallium, and subpallium in vitro human brain organoid models. These stem cell-based brain organoids are novel models to study human brain development, neurodevelopmental defects, chemical toxicity testing, and drug repurposing screening. This review focuses on the fundamentals of brain organoid development and applications. The novel applications of using cortical organoids in understanding the mechanisms of Zika virus-induced microcephaly, congenital microcephaly, and lissencephaly are also discussed.

Generation of catecholaminergic polymorphic ventricular tachycardia patient-specific induced pluripotent stem cell line

Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is a genetic disorder characterized by ventricular tachycardia, that can cause the heart to stop beating leading to death. The prevalence is 1/10.000 and in approximately 60% of cases, the syndrome can be due to a mutation of the cardiac ryanodine receptor gene (RyR2). We derived an induced pluripotent stem cell (iPSC) line from an 11-year-old patient blood-cells, carrying a heterozygous missense mutation on the 8th exon of the RyR2 N-terminal part. This reprogramed CPVT line displayed normal karyotype, expressed pluripotent markers and had a capacity to differentiate in trilineage embryonic layers.

Developmentally interdependent stretcher-compressor relationship between the embryonic brain and the surrounding scalp in the preosteogenic head.

BackgroundHow developing brains mechanically interact with the surrounding embryonic scalp layers (ie, epidermal and mesenchymal) in the preosteogenic head remains unknown. Between embryonic day (E) 11 and E13 in mice, before ossification starts in the skull vault, the angle between the pons and the medulla decreases, raising the possibility that when the elastic scalp is directly pushed outward by the growing brain and thus stretched, it recoils inward in response, thereby confining and folding the brain.ResultsStress‐release tests showed that the E11‐13 scalp recoiled and that the in vivo prestretch prerequisite for this recoil was physically dependent on the brain (pressurization at 77‐93 Pa) and on actomyosin and elastin within the scalp. In scalp‐removed heads, brainstem folding was reduced, and the spreading of ink from the lateral ventricle to the spinal cord that occurred in scalp‐intact embryos (with >5 μL injection) was lost, suggesting roles of the embryonic scalp in brain morphogenesis and cerebrospinal fluid homeostasis. Under nonstretched conditions, scalp cell proliferation declined, while the restretching of the shrunken scalp rescued scalp cell proliferation.ConclusionsIn the embryonic mouse head before ossification, a stretcher‐compressor relationship elastically develops between the brain and the scalp, underlying their mechanically interdependent development.

To Stick or Not to Stick: Adhesions in Orofacial Clefts.

Simple SummaryDuring embryonic development, cells proliferate and move to form structures essential to each organ. As these dynamic processes occur cells must form adhesions with their neighbors. These adhesions serve as communication centers to amplify the behavior of individual cells into collective cellular events. Here, we review cell-to-cell adhesions and focus on their role in the development of the face and palate.Morphogenesis requires a tight coordination between mechanical forces and biochemical signals to inform individual cellular behavior. For these developmental processes to happen correctly the organism requires precise spatial and temporal coordination of the adhesion, migration, growth, differentiation, and apoptosis of cells originating from the three key embryonic layers, namely the ectoderm, mesoderm, and endoderm. The cytoskeleton and its remodeling are essential to organize and amplify many of the signaling pathways required for proper morphogenesis. In particular, the interaction of the cell junctions with the cytoskeleton functions to amplify the behavior of individual cells into collective events that are critical for development. In this review we summarize the key morphogenic events that occur during the formation of the face and the palate, as well as the protein complexes required for cell-to-cell adhesions. We then integrate the current knowledge into a comprehensive review of how mutations in cell-to-cell adhesion genes lead to abnormal craniofacial development, with a particular focus on cleft lip with or without cleft palate.

Mature teratoma of the anterior mediastinum revealed by supravalvular pulmonary stenosis: a case report

The mature teratoma of the mediastinum is a benign tumour made up of several adult-type tissue components which result from the abnormal development of two or three embryonic layers (ectoderm, endoderm or mesoderm). We report the case of a 31-year-old patient, admitted for management of a mediastinal tumour, revealed by a pulmonary supravalvular stenosis, symptomatic of exertional dyspnea and mid-thoracic pain. The clinical examination objectified a respiratory rate at 18 c/min and an oxygen saturation at 96% in ambient air. The chest X-ray showed a mediastinal enlargement with a left paracardiac opacity, while the echocardiac showed a supravalvular pulmonary stenosis, hence the realization of a thoracic computed tomography (CT), which objectified a voluminous anterior mediastinal cystic formation and superior lateralized on the left, with an effect of compression on the trunk of the pulmonary artery. The median sternotomy allowed the complete exeresis of this tumor and the postoperative course was simple. The mature teratoma of the anterior mediastinum should be suspected in view of these clinical and radiological signs in a young patient. Surgery with a complete resection remains the treatment of choice.

Pleiotrophin, nitric oxide and glutamate AMPA receptors in chick cerebellum morphogenesis.

Avian cerebellum, a highly conserved, laminated and foliated structure, provides an excellent model for developmental studies. During the intermediate embryonic stages, granule cell progenitor proliferation and the inwards migration of post-mitotic granule cells have been implicated in the morphogenesis of cerebellar cortex cytoarchitecture and foliation. The present study questioned the spatio-temporal expression pattern of pleiotrophin, an extracellular matrix growth factor, during the morphogenesis of embryonic cerebellum, and the roles of ionotropic AMPA glutamate receptors and the diffusible neuromodulator nitric oxide (NO) in the proliferation pattern of EGL granule cell progenitors. To this end, the density of proliferating cells in the developing embryonic external granule layer (EGL) was determined following acute treatment with AMPA receptor antagonist CNQX or NO synthase inhibitor L-NAME, at embryonic stages HH38-41 (E12-E15 days), by means of BrdU immunohistochemistry and double immunofluorescence. Importantly, at earlier stages, pleiotrophin-like immunoreactivity showed high expression levels in the EGL that gradually decreased, persisting within the growing folia apices, later in development. Interestingly, blockage of AMPA receptors had no effect; while NOS inhibition resulted in transient age- and region-specific increases of EGL granule progenitor cell proliferation at earlier stages, but decreased the post-mitotic granule cells at folia apices, at a later stage HH41 (E15 day). Overall, NO had a transient anti-proliferative effect in EGL similar to mammalian cerebellum, acting as a modulator of the EGL function at different stages, suggesting its possible implication in complex processes guiding cerebellar cytoarchitecture and folia formation.

In Silico Analysis of Stem Cells Mechanical Stimulations for Mechnoregulation Toward Cardiomyocytes

Because of the ability of stem cells to self-renew and differentiate into cardiomyocytes, they are optimal cell sources for cardiac tissue engineering. Since heart cells experience cyclic strain and pulsatile flow in vivo, these mechanical stimuli are essential factors for stem cell differentiation. This study aimed to investigate the effect of a combination of pulsatile flow and cyclic strain on the shear stress created on the embryonic stem cell layer with a elastic property in a perfusion bioreactor by using the fluid-solid interaction (FSI) method. In this study, the frequency and stress phase angle had been assumed as a variable. The results show that the maximum shear stress at frequencies of 0.33, and 1 Hz and with frequency differences in cyclic strain (0.33 Hz) and pulsatile flow (1 Hz) are 0.00562, 0.02, and 0.01 dyn/cm², respectively. Moreover, in the stress phase angles 0, , and , the maximum shear stress are equal to 0.00562, 0.009, and 0.014 dyn/cm², respectively. The results of this study can be an effective step in developing cardiac tissue engineering and a better understanding of the effects of mechanical stimuli on stem cell differentiation.

Influence of light indicators on the development of Clarias gariepinus during early ontogenesis

High-quality and fast fish farming is very relevant and in demand nowadays. The african clary catfish is one of the representatives of aquatic organisms, which makes it possible to study complete embryogenesis in a short time in order to understand what favorable environmental conditions are necessary to obtain a larger volume of marketable fish. The aim of our study is to study the early stage of ontogenesis of Clarias gariepinus under the influence of changes in the degree of illumination of the environment. The material for the study was eggs obtained from females at the age of 2 years. The incubation was carried out on special mesh trays located on the surface of the pools. A total of 91000 eggs were laid for incubation. The eggs were fertilized by artificial insemination. The fertilized eggs were kept at an optimum temperature of 28,5°C. The first group was incubated in the dark, and the second under fluorescent lamps. Every 5-15 minutes, eggs were placed in a Petri dish and the material was counted and photographed using a digital camera.The results of our research showed that 20 minutes after fertilization, the onset of blastodisc formation was recorded in both groups. After 35 minutes, cell cleavage begins. The duration of this period is considered from the moment of cleavage until the complete overgrowth of the embryonic disc with cells. After 80 minutes, further division of the embryonic cell occurs with the formation of a spherical structure - morula, as well as the overgrowth of the yolk with the embryonic layer. Later 15 hours, after fertilization, we found that the development of the embryo occurs evenly, with positive dynamics, regardless of illumination.An analysis of the results obtained allows us to conclude that changes in light parameters do not have a negative effect on the rate of development of the Clarias gariepinus eggs.

Right upper lobe intrapulmonary mature cystic teratoma. An unusual location with unusual associations and a review of the literature.

IntroductionTeratomas are rare neoplasms made up of mature embryonic germ cell layers. Extra-gonadal teratomas are rare and primarily in the mediastinum. Mature cystic teratomas (MCT) are slow-growing benign tumors accounting for a small number of mediastinal germ cell tumors. Patients with MCT are often asymptomatic, and even most symptomatic intrapulmonary teratomas present with vague and non-specific symptoms such as cough, hemoptysis, and chest pain.Case presentation and discussionA Yemeni patient presented for two years with dry cough, shortness of breath, and stitching right-sided chest pain. Plain X-ray showed pleural thickening associated with two opacities in the right lung- one located centrally in the upper lobe and another peripherally- which were confirmed with a CT scan. During right-sided decortication with resection of the two masses, extensive adhesions were found between the right pleura and the chest wall. The adhesions were released, and right-sided decortication led to the removal of the peripheral cystic mass attached to the pleura. Histopathology reported the presence of squamous epithelium lining with ectodermal components such as hair follicles, sebaceous glands, keratin debris, fatty, and fibromuscular tissue.ConclusionIntrapulmonary teratomas are rare tumors, with less than 100 cases reported in the past few years. All the reported cases are in the left lung lobes, yet our case is on the right side. Although the right-sided mature cystic teratoma is even scarcer, physicians should have a high index of suspicion for teratoma when encountering abnormal lesion in the right side of the lung confirming it either by CT or MRI.

Generation of Primordial Germ Cell-like Cells from iPSCs Derived from Turner Syndrome Patients

Turner syndrome (TS) is a genetic disorder in females with X Chromosome monosomy associated with highly variable clinical features, including premature primary gonadal failure leading to ovarian dysfunction and infertility. The mechanism of development of primordial germ cells (PGCs) and their connection with ovarian failure in TS is poorly understood. An in vitro model of PGCs from TS would be beneficial for investigating genetic and epigenetic factors that influence germ cell specification. Here we investigated the potential of reprogramming peripheral mononuclear blood cells from TS women (PBMCs-TS) into iPSCs following in vitro differentiation in hPGCLCs. All hiPSCs-TS lines demonstrated pluripotency state and were capable of differentiation into three embryonic layers (ectoderm, endoderm, and mesoderm). The PGCLCs-TS recapitulated the initial germline development period regarding transcripts and protein marks, including the epigenetic profile. Overall, our results highlighted the feasibility of producing in vitro models to help the understanding of the mechanisms associated with germ cell formation in TS.

Differentiation Potential of Cultured Extracellular DEAD-Box Helicase 4+ Oogonial Stem Cells from Adult Human Ovaries into Somatic Lineages

The transdifferentiation potential of human oogonial stem cells (hOSCs) isolated using the antibody against extracellular DEAD-Box Helicase 4 (ecDDX4) remains undetermined. Hence, this study isolated OSCs from ovarian cortical pieces of premenopausal women using ecDDX4 antibody by magnetic activated cell sorting and expanded these cells under embryonic stem cell (ESC)-like culture conditions to inves­tigate their transdifferentiation potential. The number of ecDDX4+ cells obtained was variable in each isolation. When cultured on inactivated mouse embryonic fibroblast feeder layer with human leukemia inhibitory factor (hLIF) and basic fibroblast growth factor (bFGF) in Minimum Essential Medium, the hOSCs aggregated, forming ESC-like colonies. The average size of these cells was around 10 μm. hOSCs in culture were positive for alkaline phosphatase and further formed embryoid bodies (EBs) when grown on low attachment plates containing Essential 6 Medium without hLIF and bFGF. Subsequently, EBs differentiated into 3 germ layers, which were confirmed by staining with beta-III tubulin (TUJ1) for ectoderm, alpha-fetoprotein (AFP) for endoderm, and smooth muscle actin (SMA) for mesoderm. Further, using appropriate induction media, the EBs derived from ecDDX4+ hOSCs were differentiated into somatic lineages such as adipocytes, osteoblasts, cardiomyocytes, and neuronal precursor-like cells, which were confirmed by immunofluorescence using antibodies against specific markers for each cell type. This study corroborated the previous findings that ovaries of adult women possess germ cell progenitors that can be isolated using ecDDX4, and these cells can be manipulated as pluripotent stem cells by culturing them under ESC-like culture conditions akin to their male counterparts, the spermatogonial stem cells. Further, these cells could differentiate into somatic lineages under specific signalling environments.

Current Status on Canine Foetal Fluid and Adnexa Derived Mesenchymal Stem Cells.

Simple SummaryIn the last few years, dog owners have required sophisticated new treatments such as the use of MSCs for tissue engineering and regenerative medicine applications. On these topics, Canis familiaris, which develop many diseases with etiologies and pathogenesis similar to those that develop in humans, can be considered as a realistic preclinical model to evaluate the therapeutic potential of MSCs. The aim of the present review is to offer an update on the state of the art on canine MSCs derived from foetal adnexa and fluid, focusing on the findings in their clinical setting.Effective standards of care treatment guidelines have been developed for many canine diseases. However, a subpopulation of patients is partially or completely refractory to these protocols, so their owners seek novel therapies such as treatments with MSCs. Although in dogs, as with human medicine, the most studied MSCs sources have been bone marrow and adipose tissue, in recent years, many researchers have drawn attention towards alternative sources, such as foetal adnexa and fluid, since they possess many advantages over bone marrow and adipose tissue. Foetal adnexa and fluid could be considered as discarded material; therefore, sampling is non-invasive, inexpensive and free from ethical considerations. Furthermore, MSCs derived from foetal adnexa and fluid preserve some of the characteristics of the primitive embryonic layers from which they originate and seem to present immune-modulatory properties that make them a good candidate for allo- and xenotransplantation. The aim of the present review is to offer an update on the state of the art on canine MSCs derived from foetal adnexa and fluid focusing on the findings in their clinical setting.

A sacrococcygeal teratoma-a rare entity among adult males: a case report and review of literature

Sacrococcygeal teratoma (SCT) is derived from embryonic germ cell layers and is one of the commonest tumours in infants. It is the most commonly occurring solid congenital tumours in the foetus and the new born. It is very rare in adults with less than a hundred cases documented in literature, with even rarer cases of male presentation. We report a case of a 26-year-old adult male presenting with a sacrococcygeal teratoma who was treated in our hospital along with its literature review.

IS IT POSSIBLE TO MODEL JERVELL AND LANGE-NIELSEN SYNDROME (JLNS) USING PATIENT-SPECIFIC INDUCED PLURIPOTENT STEM CELLS (IPSC)?

<h3>Background</h3> JLNS is a rare channelopathy caused by mutations in the KCNQ1 and KCNE1 genes that encodes the α and β subunits of the IKS current channel. Patients with JLNS have congenital bilateral deafness and prolongation of the QT interval on electrocardiogram (ECG), which can lead to arrhythmias, syncope, and a high risk of sudden death. Induced pluripotent stem cells-derived cardiomyocytes (iPSC-CM) can be a useful tool to recapitulate the disease phenotype in vitro enabling the comprehension of its molecular and cellular mechanisms. <h3>Methods</h3> The DNA of a proband with clinical symptoms of JVLNS was analyzed by next-generation sequencing. Sanger was done on samples from family members. iPSC were generated from the proband (Pac6), a cousin (Pac53) suspect of JLNS, the grandfather (Pac25), his sister (Pac24), and his mother (Pac8). iPSC were evaluated for euploidy and characterized for pluripotency by PCR, flow cytometry, and immunohistochemistry. iPSC were differentiated into CMs and its efficiency was assessed by flow cytometry. Electrophysiology was evaluated by intracellular microelectrode (PA) and microelectrode array (MEA). <h3>Results</h3> A homozygous variant c.1394-2A>G was identified in the KCNQ1 gene of Pac6 and Pac53. Both have congenital bilateral deafness and a QTc interval of 670 and 660ms respectively. Pac25 and Pac24 have no mutation and Pac8 have the variant in heterozygosis (Long QT syndrome type 1 - LQTS1). iPSC showed pluripotency markers in PCR and Flow Cytometry (OCT3/4, SOX2, NANOG, etc) and the capacity to differentiate in 3 embryonic layers (shown by immunohistochemistry and PCR). iPSC karyotype was normal, except for Pac53, in which there‘s a translocation between chromosomes 14 and 22. The iPSC-CM had differentiation efficiency above 70%. Surprisingly, electrophysiology functional analysis of action potential duration at 90% of repolarization (APD90) showed no significant differences between Pac6 (APD90 = 255,67 ± 39,19) and Pac53 (APD90 = 315,45 ± 74,71) compared to Pac24 (APD90 = 262,22 ± 62,81) and Pac25 (APD90 = 215,43 ± 73,83). Similar results were observed when analyzed by MEA. <h3>Conclusion</h3> This work is unique to modeling a non-described mutation in the KCNQ1 gene present in a family with two JLNS and one asymptomatic LQTS1. The complete understanding of why the CM-iPSC failed to mimetics in vitro disease demands further investigation challenging the cells with pro-arrhythmic drugs and iKS inhibitors.

DEVELOPMENT OF AN IN VITRO STUDY MODEL OF PRKAG2 CARDIOMYOPATHY USING HUMAN INDUCED PLURIPOTENT STEM CELLS

<h3>Background</h3> PRKAG2 cardiomyopathy is an autosomal dominant syndrome due to mutation in PRKAG2 gene, which encodes the γ2 subunit of the adenosine monophosphate (AMP)-activated protein kinase (AMPK). PRKAG2 syndrome leads to intracellular cardiomyocyte glycogen storage dysfunctions and clinical conditions that overlap hypertrophic cardiomyopathy, hampering its correct diagnosis. Our group identified a patient with a novel heterozygous missense mutation in PRKAG2 gene (c.1203C>A, p.His401Gln), with a malignant disease phenotype characterized by severe cardiac hypertrophy and cases of sudden death in young relatives. In this regard, induced pluripotent stem cells (iPSC) preserve the donor genome and can be differentiated into specialized cell types, being particularly interesting to study diseases that affect tissues which are difficult to access. Thus, this work aims to establish an in vitro study model of PRKAG2 cardiomyopathy through generation of human iPSC and its subsequent differentiation into patient-specific cardiomyocytes. <h3>Methods</h3> iPSC from patient with PRKAG2 mutation and from a health relative were generated from erythroblasts using CytoTune™-iPSC 2.0 Sendai Reprogramming Kit (containing OCT3/4, KLF4, SOX2 and cMYC as reprogramming factors) and their karyotype was analyzed by qPCR using hPSC Genetic Analysis Kit (Stemcell Technologies). The iPSC strains obtained were differentiated into cardiomyocytes by inducing mesoderma formation with glycogen synthase kinase inhibitor 3-β, CHIR99021 (5 µM), on day 0 and cardiogenic mesoderma formation with the Wnt inhibitor, Wnt-C59 (2 µM), on day 2. On day 30 of culture, cells were stained with periodic acid-Schiff (PAS) to assess cytosolic glycogen storage. <h3>Results</h3> Both iPSC strains have embryonic-like phenotype and normal karyotype. Moreover, preliminary differentiation studies suggest glycogen accumulation in cardiomyocytes derived from the iPSC strain with PRKAG2 mutation. Evaluation of pluripotency factors expression and the ability to differentiate in the 3 embryonic germinative layers are ongoing in iPSC strains. <h3>Conclusion</h3> At the end of the characterization of the generated iPSC and of iPSC-derived cardiomyocytes, is expected that this approach will make possible the establishment of an in vitro study platform to reveal molecular mechanisms triggered by the c.1203C>A mutation that may contribute to the development of new therapies and prognostic evaluation of patients with PRKAG2 syndrome.

Vaginal dermoid cyst

A 27-year-old gravida 1 para 1 presented with a painless, left anterolateral vaginal wall mass, measuring 10 cm in diameter, which had been slowly growing over several years. Pelvic magnetic resonance images were concerning for a large Gartner’s duct cyst based on the location and appearance of the mass (Figure 1). After an uncomplicated vaginal cystectomy, the mass grossly revealed spillage of sebaceous material and the presence of hair (Figure 2). Further pathohistologic evaluation confirmed the diagnosis of a rare vaginal dermoid cyst (mature cystic teratoma) given the presence of squamous epithelium, sebaceous glands, hair follicles, capillaries, and adipose tissue, representing all 3 embryonic layers (Figures 3 and 4).