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1.
Front Med (Lausanne) ; 11: 1340905, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38414622

RESUMO

Cases of hydatidiform moles with a coexisting fetus are sparse and patients are at high risk for severe complications. Patients and physicians often face the dilemma of the wish to continue pregnancy until viability of the fetus while the risk for maternal complications increases. We present an educational case of a twin pregnancy presenting with a hydatidiform mole and coexisting normal fetus with a placenta praevia. The patient developed severe, early onset preeclampsia with beginning HELLP-syndrome and was tested Covid-19 positive in the further course. Termination of pregnancy was conducted via caesarean section at 18 + 6 weeks of pregnancy. Histopathology and genetic analysis confirmed a complete hydatidiform mole next to a normal placenta. Close follow-up examinations were conducted and showed normal findings including ß HCG levels normalizing within 5 months. This case combines several rare, difficult and severe medical conditions and demonstrates how an individualized therapy by an interdisciplinary team covering a highly sensitive topic was developed in a situation where no guidelines exist.

2.
J Clin Invest ; 134(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38165034

RESUMO

The infertility of many couples rests on an enigmatic dysfunction of the man's sperm. To gain insight into the underlying pathomechanisms, we assessed the function of the sperm-specific multisubunit CatSper-channel complex in the sperm of almost 2,300 men undergoing a fertility workup, using a simple motility-based test. We identified a group of men with normal semen parameters but defective CatSper function. These men or couples failed to conceive naturally and upon medically assisted reproduction via intrauterine insemination and in vitro fertilization. Intracytoplasmic sperm injection (ICSI) was, ultimately, required to conceive a child. We revealed that the defective CatSper function was caused by variations in CATSPER genes. Moreover, we unveiled that CatSper-deficient human sperm were unable to undergo hyperactive motility and, therefore, failed to penetrate the egg coat. Thus, our study provides the experimental evidence that sperm hyperactivation is required for human fertilization, explaining the infertility of CatSper-deficient men and the need of ICSI for medically assisted reproduction. Finally, our study also revealed that defective CatSper function and ensuing failure to hyperactivate represents the most common cause of unexplained male infertility known thus far and that this sperm channelopathy can readily be diagnosed, enabling future evidence-based treatment of affected couples.


Assuntos
Infertilidade Masculina , Sêmen , Criança , Humanos , Masculino , Sêmen/fisiologia , Canais de Cálcio/genética , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Infertilidade Masculina/terapia , Infertilidade Masculina/genética , Fertilização In Vitro , Fertilização/fisiologia
3.
FASEB J ; 37(5): e22912, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37086090

RESUMO

The family of WWC proteins is known to regulate cell proliferation and organ growth control via the Hippo signaling pathway. As WWC proteins share a similar domain structure and a common set of interacting proteins, they are supposed to fulfill compensatory functions in cells and tissues. While all three WWC family members WWC1, WWC2, and WWC3 are found co-expressed in most human organs including lung, brain, kidney, and liver, in the testis only WWC2 displays a relatively high expression. In this study, we investigated the testicular WWC2 expression in spermatogenesis and male fertility. We show that the Wwc2 mRNA expression level in mouse testes is increased during development in parallel with germ cell proliferation and differentiation. The cellular expression of each individual WWC family member was evaluated in published single-cell mRNA datasets of murine and human testes demonstrating a high WWC2 expression predominantly in early spermatocytes. In line with this, immunohistochemistry revealed cytosolic WWC2 protein expression in primary spermatocytes from human testes displaying full spermatogenesis. In accordance with these findings, markedly lower WWC2 expression levels were detected in testicular tissues from mice and men lacking germ cells. Finally, analysis of whole-exome sequencing data of male patients affected by infertility and unexplained severe spermatogenic failure revealed several heterozygous, rare WWC2 gene variants with a proposed damaging function and putative impact on WWC2 protein structure. Taken together, our findings provide novel insights into the testicular expression of WWC2 and show its cell-specific expression in spermatocytes. As rare WWC2 variants were identified in the background of disturbed spermatogenesis, WWC2 may be a novel candidate gene for male infertility.


Assuntos
Infertilidade Masculina , Espermatogênese , Testículo , Animais , Humanos , Masculino , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fertilidade/genética , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espermatogênese/genética , Testículo/metabolismo
4.
Eur Urol ; 83(5): 452-462, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35690514

RESUMO

BACKGROUND: Crypto- and azoospermia (very few/no sperm in the semen) are main contributors to male factor infertility. Genetic causes for spermatogenic failure (SPGF) include Klinefelter syndrome and Y-chromosomal azoospermia factor microdeletions, and CFTR mutations for obstructive azoospermia (OA). However, the majority of cases remain unexplained because monogenic causes are not analysed. OBJECTIVE: To elucidate the monogenic contribution to azoospermia by prospective exome sequencing and strict application of recent clinical guidelines. DESIGN, SETTING, AND PARTICIPANTS: Since January 2017, we studied crypto- and azoospermic men without chromosomal aberrations and Y-chromosomal microdeletions attending the Centre of Reproductive Medicine and Andrology, Münster. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We performed exome sequencing in 647 men, analysed 60 genes having at least previous limited clinical validity, and strictly assessed variants according to clinical guidelines. RESULTS AND LIMITATIONS: Overall, 55 patients (8.5%) with diagnostic genetic variants were identified. Of these patients, 20 (3.1%) carried mutations in CFTR or ADGRG2, and were diagnosed with OA. In 35 patients (5.4%) with SPGF, mutations in 20 different genes were identified. According to ClinGen criteria, 19 of the SPGF genes now reach at least moderate clinical validity. As limitations, only one transcript per gene was considered, and the list of genes is increasing rapidly so cannot be exhaustive. CONCLUSIONS: The number of diagnostic genes in crypto-/azoospermia was almost doubled to 21 using exome-based analyses and clinical guidelines. Application of this procedure in routine diagnostics will significantly improve the diagnostic yield and clinical workup as the results indicate the success rate of testicular sperm extraction. PATIENT SUMMARY: When no sperm are found in the semen, a man cannot conceive naturally. The causes are often unknown, but genetics play a major role. We searched for genetic variants in a large group of patients and found causal mutations for one in 12 men; these predict the chances for fatherhood.


Assuntos
Azoospermia , Infertilidade Masculina , Humanos , Masculino , Azoospermia/genética , Azoospermia/complicações , Azoospermia/diagnóstico , Estudos Prospectivos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Padrão de Cuidado , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/genética , Testículo
5.
Ultraschall Med ; 44(5): e241-e247, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36198323

RESUMO

PURPOSE: Congenital limb defects are common malformations that are often associated with other organ defects and genetic disorders. Since prenatal detection is challenging and classification is often complex, the aim of this study was to describe a large cohort of fetuses with congenital limb defects and to identify characteristics that are essential for prenatal evaluation, counselling, and management. MATERIALS AND METHODS: In this retrospective cohort study, all cases of confirmed fetal limb defects from two centers for prenatal ultrasound between 2001 and 2021 were evaluated. Cases with skeletal dysplasia were excluded from this study. Demographic data, association with genetic disorders, and correlation with maternal parameters were analyzed statistically. RESULTS: 170 fetuses were included in this study. 60% were diagnosed with a reduction anomaly and 40% with a duplication anomaly. The majority of fetuses were male, and in 73.5% of all cases, additional malformations were present. Among the genetic causes, trisomy 13 and 18 were the most common in this cohort. CONCLUSION: Congenital limb malformations are important markers for complex fetal disorders that warrant referral to specialists in prenatal ultrasound. To improve prenatal detection, care should be taken to visualize all fetal extremities already in early pregnancy.

6.
Stem Cell Res ; 62: 102826, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35667217

RESUMO

An induced pluripotent stem cell (hiPSC) line (MPIi008-A) was generated from fibroblasts of a 1-year-old male patient with Denys-Drash syndrome using lentiviral delivery of reprogramming factors OCT4, SOX2, KLF4 and c-MYC. The MPIi008-A iPSC line exhibited typical iPSC morphology and normal karyotype, expressed pluripotent stem cell markers, and showed developmental potential to differentiate into derivatives of all three germ layers in vivo. The hiPSC line harbours a heterozygous missense mutation (R394L) in exon 9 of the WT1 gene.


Assuntos
Síndrome de Denys-Drash , Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Diferenciação Celular , Síndrome de Denys-Drash/metabolismo , Fibroblastos/metabolismo , Heterozigoto , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Lactente , Masculino , Mutação
7.
Sci Rep ; 10(1): 16804, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033381

RESUMO

A detailed description of pathophysiological effects that viruses exert on their host is still challenging. For the first time, we report a highly controllable viral expression model based on an iPS-cell line from a healthy human donor. The established viral model system enables a dose-dependent and highly localized RNA-virus expression in a fully controllable environment, giving rise for new applications for the scientific community.


Assuntos
Células-Tronco Pluripotentes Induzidas/virologia , Infecções por Vírus de RNA/virologia , Vírus de RNA/fisiologia , Linhagem Celular , Doxiciclina/farmacologia , Humanos , Modelos Biológicos , Miócitos Cardíacos/virologia , Ativação Viral/efeitos dos fármacos
8.
Stem Cell Res ; 48: 101993, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32950023

RESUMO

Here we have generated a human induced pluripotent stem cells (hiPSC) line (MPIi007-A) from skin fibroblasts of a 4-year-old male Metachromatic leukodystrophy (MLD) patient with a heterozygous 1178C > G (Thr393Ser) mutation in arylsulfatase A (ARSA) gene via retroviral expression of OCT4, SOX2, KLF4 and c-MYC. The MPIi007-A iPSC line displayed typical embryonic stem cell-like morphology, carried the ARSA gene mutation, expressed several pluripotent stem cell makers, retained normal karyotype (46, XY) and were capable of forming teratomas containing three germ layers. The MPIi007-A line can be used for the characterization of MLD-associated pathomechanisms and developing new therapeutic options.


Assuntos
Células-Tronco Pluripotentes Induzidas , Leucodistrofia Metacromática , Cerebrosídeo Sulfatase/genética , Pré-Escolar , Heterozigoto , Humanos , Fator 4 Semelhante a Kruppel , Leucodistrofia Metacromática/genética , Masculino , Mutação
9.
Acta Neuropathol ; 140(5): 715-736, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32894330

RESUMO

Multiple sclerosis (MS) is the most frequent demyelinating disease in young adults and despite significant advances in immunotherapy, disease progression still cannot be prevented. Promotion of remyelination, an endogenous repair mechanism resulting in the formation of new myelin sheaths around demyelinated axons, represents a promising new treatment approach. However, remyelination frequently fails in MS lesions, which can in part be attributed to impaired differentiation of oligodendroglial progenitor cells into mature, myelinating oligodendrocytes. The reasons for impaired oligodendroglial differentiation and defective remyelination in MS are currently unknown. To determine whether intrinsic oligodendroglial factors contribute to impaired remyelination in relapsing-remitting MS (RRMS), we compared induced pluripotent stem cell-derived oligodendrocytes (hiOL) from RRMS patients and controls, among them two monozygous twin pairs discordant for MS. We found that hiOL from RRMS patients and controls were virtually indistinguishable with respect to remyelination-associated functions and proteomic composition. However, while analyzing the effect of extrinsic factors we discovered that supernatants of activated peripheral blood mononuclear cells (PBMCs) significantly inhibit oligodendroglial differentiation. In particular, we identified CD4+ T cells as mediators of impaired oligodendroglial differentiation; at least partly due to interferon-gamma secretion. Additionally, we observed that blocked oligodendroglial differentiation induced by PBMC supernatants could not be restored by application of oligodendroglial differentiation promoting drugs, whereas treatment of PBMCs with the immunomodulatory drug teriflunomide prior to supernatant collection partly rescued oligodendroglial differentiation. In summary, these data indicate that the oligodendroglial differentiation block is not due to intrinsic oligodendroglial factors but rather caused by the inflammatory environment in RRMS lesions which underlines the need for drug screening approaches taking the inflammatory environment into account. Combined, these findings may contribute to the development of new remyelination promoting strategies.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Esclerose Múltipla Recidivante-Remitente/imunologia , Oligodendroglia/patologia , Remielinização/imunologia , Diferenciação Celular/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas , Interferon gama/imunologia , Células Precursoras de Oligodendrócitos/patologia
10.
Sci Adv ; 6(36)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32917606

RESUMO

OCT4 (also known as POU5F1) plays an essential role in reprogramming. It is the only member of the POU (Pit-Oct-Unc) family of transcription factors that can induce pluripotency despite sharing high structural similarities to all other members. Here, we discover that OCT6 (also known as POU3F1) can elicit reprogramming specifically in human cells. OCT6-based reprogramming does not alter the mesenchymal-epithelial transition but is attenuated through the delayed activation of the pluripotency network in comparison with OCT4-based reprogramming. Creating a series of reciprocal domain-swapped chimeras and mutants across all OCT factors, we clearly delineate essential elements of OCT4/OCT6-dependent reprogramming and, conversely, identify the features that prevent induction of pluripotency by other OCT factors. With this strategy, we further discover various chimeric proteins that are superior to OCT4 in reprogramming. Our findings clarify how reprogramming competences of OCT factors are conferred through their structural components.

11.
Am J Hum Genet ; 107(2): 342-351, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32673564

RESUMO

Male infertility affects ∼7% of men, but its causes remain poorly understood. The most severe form is non-obstructive azoospermia (NOA), which is, in part, caused by an arrest at meiosis. So far, only a few validated disease-associated genes have been reported. To address this gap, we performed whole-exome sequencing in 58 men with unexplained meiotic arrest and identified the same homozygous frameshift variant c.676dup (p.Trp226LeufsTer4) in M1AP, encoding meiosis 1 associated protein, in three unrelated men. This variant most likely results in a truncated protein as shown in vitro by heterologous expression of mutant M1AP. Next, we screened four large cohorts of infertile men and identified three additional individuals carrying homozygous c.676dup and three carrying combinations of this and other likely causal variants in M1AP. Moreover, a homozygous missense variant, c.1166C>T (p.Pro389Leu), segregated with infertility in five men from a consanguineous Turkish family. The common phenotype between all affected men was NOA, but occasionally spermatids and rarely a few spermatozoa in the semen were observed. A similar phenotype has been described for mice with disruption of M1ap. Collectively, these findings demonstrate that mutations in M1AP are a relatively frequent cause of autosomal recessive severe spermatogenic failure and male infertility with strong clinical validity.


Assuntos
Pontos de Checagem do Ciclo Celular/genética , Infertilidade Masculina/genética , Meiose/genética , Mutação/genética , Proteínas/genética , Espermatogênese/genética , Adulto , Alelos , Animais , Azoospermia/genética , Homozigoto , Humanos , Masculino , Camundongos , Fenótipo , Espermatozoides/anormalidades , Testículo/anormalidades , Turquia , Sequenciamento do Exoma/métodos
12.
J Biol Chem ; 295(38): 13181-13193, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32703901

RESUMO

The sperm-specific Ca2+ channel CatSper (cation channel of sperm) controls the influx of Ca2+ into the flagellum and, thereby, the swimming behavior of sperm. A hallmark of human CatSper is its polymodal activation by membrane voltage, intracellular pH, and oviductal hormones. Whether CatSper is also activated by signaling pathways involving an increase of cAMP and ensuing activation of PKA is, however, a matter of controversy. To shed light on this question, we used kinetic ion-sensitive fluorometry, patch-clamp recordings, and optochemistry to study transmembrane Ca2+ flux and membrane currents in human sperm from healthy donors and from patients that lack functional CatSper channels. We found that human CatSper is neither activated by intracellular cAMP directly nor indirectly by the cAMP/PKA-signaling pathway. Instead, we show that nonphysiological concentrations of cAMP and membrane-permeable cAMP analogs used to mimic the action of intracellular cAMP activate human CatSper from the outside via a hitherto-unknown extracellular binding site. Finally, we demonstrate that the effects of common PKA inhibitors on human CatSper rest predominantly, if not exclusively, on off-target drug actions on CatSper itself rather than on inhibition of PKA. We conclude that the concept of an intracellular cAMP/PKA-activation of CatSper is primarily based on unspecific effects of chemical probes used to interfere with cAMP signaling. Altogether, our findings solve several controversial issues and reveal a novel ligand-binding site controlling the activity of CatSper, which has important bearings on future studies of cAMP and Ca2+ signaling in sperm.


Assuntos
Canais de Cálcio/metabolismo , Sinalização do Cálcio , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Espermatozoides/metabolismo , Canais de Cálcio/genética , AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/genética , Humanos , Concentração de Íons de Hidrogênio , Masculino , Espermatozoides/citologia
13.
Stem Cell Res ; 46: 101855, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32512309

RESUMO

Crisponi syndrome/cold-induced sweating syndrome type 2 (CS/CISS2) is a rare disease with severe dysfunctions of thermoregulatory processes. CS/CISS2 individuals suffer from recurrent episodes of hyperthermia in the neonatal period and paradoxical sweating at cold ambient temperatures in adolescence. Variants in CLCF1 (cardiotrophin-like-cytokine 1) cause CS/CISS2. Here, we summarize the generation of three clones of one stem cell line (iPSC) of a CS/CISS2 individual carrying the CLCF1 variant c.321C>G on both alleles. These patient derived iPSC clones show a normal karyotype, several pluripotency markers, and the ability to differentiate into the three germ layers.


Assuntos
Células-Tronco Pluripotentes Induzidas , Adolescente , Reprogramação Celular , Células Clonais , Morte Súbita , Facies , Fibroblastos , Deformidades Congênitas da Mão , Humanos , Hiperidrose , Recém-Nascido , Receptores de Citocinas/genética , Trismo/congênito
14.
Stem Cell Res ; 46: 101820, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32492556

RESUMO

Cytokine receptor like factor 1 (CRLF1) is the gene implicated, when mutated, in Crisponi syndrome/cold-induced sweating syndrome type 1 (CS/CISS1). Here, we report the establishment of induced pluripotent stem cell lines (iPSCs) from fibroblasts of a Turkish CS/CISS1 individual with a homozygous variant in CRLF1 (c.708_709delinsT; p.[Pro238Argfs*6]). This variant is the most frequent variant associated to CS/CISS1 in the Turkish population. These patient derived iPSC lines show all pluripotency markers, a normal karyotype and the ability to differentiate into the three germ layers.


Assuntos
Deformidades Congênitas da Mão , Hiperidrose , Células-Tronco Pluripotentes Induzidas , Facies , Humanos , Sudorese
15.
Stem Cell Res ; 46: 101839, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32446239

RESUMO

We established a human induced pluripotent stem cells (hiPSC) line (MPIi006-A) from fibroblasts of a 20-year-old male Pelizaeus-Merzbacher disease (PMD) patient with a hemizygous 643C>T mutation in proteolipid protein 1 (PLP1) gene using a retroviral delivery of OCT4, SOX2, KLF4 and c-MYC. The MPIi006-A iPSC line carried the mutation, displayed typical iPSC morphology, expressed pluripotent stem cell makers, exhibited normal karyotype and were capable of differentiating into cells representative of three germ layers.


Assuntos
Células-Tronco Pluripotentes Induzidas , Doença de Pelizaeus-Merzbacher , Fibroblastos , Humanos , Fator 4 Semelhante a Kruppel , Masculino , Mutação , Proteína Proteolipídica de Mielina/genética , Doença de Pelizaeus-Merzbacher/genética , Adulto Jovem
16.
EMBO J ; 39(4): e102363, 2020 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-31957048

RESUMO

Navigation of sperm in fluid flow, called rheotaxis, provides long-range guidance in the mammalian oviduct. The rotation of sperm around their longitudinal axis (rolling) promotes rheotaxis. Whether sperm rolling and rheotaxis require calcium (Ca2+ ) influx via the sperm-specific Ca2+ channel CatSper, or rather represent passive biomechanical and hydrodynamic processes, has remained controversial. Here, we study the swimming behavior of sperm from healthy donors and from infertile patients that lack functional CatSper channels, using dark-field microscopy, optical tweezers, and microfluidics. We demonstrate that rolling and rheotaxis persist in CatSper-deficient human sperm. Furthermore, human sperm undergo rolling and rheotaxis even when Ca2+ influx is prevented. Finally, we show that rolling and rheotaxis also persist in mouse sperm deficient in both CatSper and flagellar Ca2+ -signaling domains. Our results strongly support the concept that passive biomechanical and hydrodynamic processes enable sperm rolling and rheotaxis, rather than calcium signaling mediated by CatSper or other mechanisms controlling transmembrane Ca2+ flux.


Assuntos
Hidrodinâmica , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Animais , Fenômenos Biomecânicos , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Humanos , Masculino , Camundongos , Proteínas de Plasma Seminal/genética , Proteínas de Plasma Seminal/metabolismo
17.
Eur J Nucl Med Mol Imaging ; 47(9): 2131-2141, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31960097

RESUMO

PURPOSE: Primary angiitis of the central nervous system (PACNS) is a heterogeneous, rare, and poorly understood inflammatory disease. We aimed at non-invasive imaging of activated microglia/macrophages in patients with PACNS by PET-MRI targeting the translocator protein (TSPO) with [18F]DPA-714 to potentially assist differential diagnosis, therapy monitoring, and biopsy planning. METHODS: In total, nine patients with ischemic stroke and diagnosed or suspected PACNS underwent [18F]DPA-714-PET-MRI. Dynamic PET scanning was performed for 60 min after injection of 233 ± 19 MBq [18F]DPA-714, and MRI was simultaneously acquired. RESULTS: In two PACNS patients, [18F]DPA-714 uptake patterns exceeded MRI correlates of infarction, whereas uptake was confined to the infarct in four patients where initial suspicion of PACNS could not be confirmed. About three patients with PACNS or cerebral predominant lymphocytic vasculitis showed no or only faintly increased uptake. Short-term [18F]DPA-714-PET follow-up in a patient with PACNS showed reduced lesional [18F]DPA-714 uptake after anti-inflammatory treatment. Biopsy in the same patient pinpointed the source of tracer uptake to TSPO-expressing immune cells. CONCLUSIONS: [18F]DPA-714-PET imaging may facilitate the diagnosis and treatment monitoring of PACNS. Further studies are needed to fully understand the potential of TSPO-PET in deciphering the heterogeneity of the disease.


Assuntos
Radioisótopos de Flúor , Tomografia por Emissão de Pósitrons , Humanos , Inflamação/diagnóstico por imagem , Pirazóis , Pirimidinas , Receptores de GABA , Vasculite do Sistema Nervoso Central
18.
Med Genet ; 30(1): 12-20, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527098

RESUMO

Infertility is a common condition estimated to affect 10-15% of couples. The clinical causes are attributed in equal parts to the male and female partners. Diagnosing male infertility mostly relies on semen (and hormone) analysis, which results in classification into the two major phenotypes of oligo- and azoospermia. The clinical routine analyses have not changed over the last 20 years and comprise screening for chromosomal aberrations and Y­chromosomal azoospermia factor deletions. These tests establish a causal genetic diagnosis in about 4% of unselected men in infertile couples and 20% of azoospermic men. Gene sequencing is currently only performed in very rare cases of hypogonadotropic hypogonadism and the CFTR gene is routinely analysed in men with obstructive azoospermia. Still, a large number of genes have been proposed to be associated with male infertility by, for example, knock-out mouse models. In particular, those that are exclusively expressed in the testes are potential candidates for further analyses. However, the genome-wide analyses (a few array-CGH, six GWAS, and some small exome sequencing studies) performed so far have not lead to improved clinical diagnostic testing. In 2017, we started to routinely analyse the three validated male infertility genes: NR5A1, DMRT1, and TEX11. Preliminary analyses demonstrated highly likely pathogenic mutations in these genes as a cause of azoospermia in 4 men, equalling 5% of the 80 patients analysed so far, and increasing the diagnostic yield in this group to 25%. Over the past few years, we have observed a steep increase in publications on novel candidate genes for male infertility, especially in men with azoospermia. In addition, concerted efforts to achieve progress in elucidating genetic causes of male infertility and to introduce novel testing strategies into clinical routine have been made recently. Thus, we are confident that major breakthroughs concerning the genetics of male infertility will be achieved in the near future and will translate into clinical routine to improve patient/couple care.

19.
Nat Commun ; 9(1): 440, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29382828

RESUMO

Master cell fate determinants are thought to induce specific cell lineages in gastrulation by orchestrating entire gene programs. The T-box transcription factor EOMES (eomesodermin) is crucially required for the development of the heart-yet it is equally important for endoderm specification suggesting that it may act in a context-dependent manner. Here, we define an unrecognized interplay between EOMES and the WNT signaling pathway in controlling cardiac induction by using loss and gain-of-function approaches in human embryonic stem cells. Dose-dependent EOMES induction alone can fully replace a cocktail of signaling molecules otherwise essential for the specification of cardiogenic mesoderm. Highly efficient cardiomyocyte programming by EOMES mechanistically involves autocrine activation of canonical WNT signaling via the WNT3 ligand, which necessitates a shutdown of this axis at a subsequent stage. Our findings provide insights into human germ layer induction and bear biotechnological potential for the robust production of cardiomyocytes from engineered stem cells.


Assuntos
Técnicas de Reprogramação Celular/métodos , Células-Tronco Pluripotentes/citologia , Proteínas com Domínio T/genética , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Doxiciclina/administração & dosagem , Doxiciclina/farmacologia , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Células-Tronco Embrionárias Humanas/citologia , Humanos , Mesoderma , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Proteínas com Domínio T/metabolismo , Via de Sinalização Wnt , Proteína Wnt3/metabolismo
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