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1.
Psychophysiology ; : e14571, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679809

RESUMO

Given experience in cluttered but stable visual environments, our eye-movements form stereotyped routines that sample task-relevant locations, while not mixing-up routines between similar task-settings. Both dopamine signaling and mindfulness have been posited as factors that influence the formation of such routines, yet quantification of their impact remains to be tested in healthy humans. Over two sessions, participants searched through grids of doors to find hidden targets, using a gaze-contingent display. Within each session, door scenes appeared in either one of two colors, with each color signaling a differing set of likely target locations. We derived measures for how well target locations were learned (target-accuracy), how routine were sets of eye-movements (stereotypy), and the extent of interference between the two scenes (setting-accuracy). Participants completed two sessions, where they were administered either levodopa (dopamine precursor) or placebo (vitamin C), under double-blind counterbalanced conditions. Dopamine and trait mindfulness (assessed by questionnaire) interacted to influence both target-accuracy and stereotypy. Increasing dopamine improved accuracy and reduced stereotypy for high mindfulness scorers, but induced the opposite pattern for low mindfulness scorers. Dopamine also disrupted setting-accuracy invariant to mindfulness. Our findings show that mindfulness modulates the impact of dopamine on the target-accuracy and stereotypy of eye-movement routines, whereas increasing dopamine promotes interference between task-settings, regardless of mindfulness. These findings provide a link between non-human and human models regarding the influence of dopamine on the formation of task-relevant eye-movement routines and provide novel insights into behavior-trait factors that modulate the use of experience when building adaptive repertoires.

2.
Nat Commun ; 13(1): 7860, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36543770

RESUMO

Seminiferous tubules (STs) in the mammalian testes are connected to the rete testis (RT) via a Sertoli valve (SV). Spermatozoa produced in the STs are released into the tubular luminal fluid and passively transported through the SV into the RT. However, the physiological functions of the RT and SV remain unclear. Here, we identified the expression of Sox17 in RT epithelia. The SV valve was disrupted before puberty in RT-specific Sox17 conditional knockout (Sox17-cKO) male mice. This induced a backflow of RT fluid into the STs, which caused aberrant detachment of immature spermatids. RT of Sox17-cKO mice had reduced expression levels of various growth factor genes, which presumably support SV formation. When transplanted next to the Sox17+ RT, Sertoli cells of Sox17-cKO mice reconstructed the SV and supported proper spermiogenesis in the STs. This study highlights the novel and unexpected modulatory roles of the RT in SV valve formation and spermatogenesis in mouse testes, as a downstream action of Sox17.


Assuntos
Rede do Testículo , Fatores de Transcrição SOXF , Maturidade Sexual , Espermatogênese , Animais , Masculino , Camundongos , Epitélio , Proteínas HMGB/metabolismo , Mamíferos , Camundongos Knockout , Rede do Testículo/metabolismo , Células de Sertoli/metabolismo , Fatores de Transcrição SOXF/genética , Fatores de Transcrição SOXF/metabolismo , Espermatogênese/genética , Testículo/metabolismo
3.
Int J Mol Sci ; 23(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36362161

RESUMO

In most mammals, the sex of the gonads is based on the fate of the supporting cell lineages, which arises from the proliferation of coelomic epithelium (CE) that surfaces on the bipotential genital ridge in both XY and XX embryos. Recent genetic studies and single-cell transcriptome analyses in mice have revealed the cellular and molecular events in the two-wave proliferation of the CE that produce the supporting cells. This proliferation contributes to the formation of the primary sex cords in the medullary region of both the testis and the ovary at the early phase of gonadal sex differentiation, as well as to that of the secondary sex cords in the cortical region of the ovary at the perinatal stage. To support gametogenesis, the testis forms seminiferous tubules in the medullary region, whereas the ovary forms follicles mainly in the cortical region. The medullary region in the ovary exhibits morphological and functional diversity among mammalian species that ranges from ovary-like to testis-like characteristics. This review focuses on the mechanism of gonadal sex differentiation along the cortical-medullary axis and compares the features of the cortical and medullary regions of the ovary in mammalian species.


Assuntos
Ovário , Diferenciação Sexual , Masculino , Feminino , Camundongos , Animais , Diferenciação Sexual/genética , Gônadas , Testículo , Organogênese , Mamíferos
4.
Eur J Neurosci ; 54(3): 5047-5062, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34021941

RESUMO

Sensorimotor adaptation is an important part of our ability to perform novel motor tasks (i.e., learning of motor skills). Efforts to improve adaptation in healthy and clinical patients using non-invasive brain stimulation methods have been hindered by inter-individual and intra-individual variability in brain susceptibility to stimulation. Here, we explore unpredictable loud acoustic stimulation as an alternative method of modulating brain excitability to improve sensorimotor adaptation. In two experiments, participants moved a cursor towards targets, and adapted to a 30º rotation of cursor feedback, either with or without unpredictable acoustic stimulation. Acoustic stimulation improved initial adaptation to sensory prediction errors in Study 1, and improved overnight retention of adaptation in Study 2. Unpredictable loud acoustic stimulation might thus be a potent method of modulating sensorimotor adaptation in healthy adults.


Assuntos
Adaptação Fisiológica , Retroalimentação Sensorial , Estimulação Acústica , Adulto , Humanos , Aprendizagem , Desempenho Psicomotor , Rotação
6.
Sci Rep ; 11(1): 1110, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441739

RESUMO

In mammalian testes, undifferentiated spermatogonia (Aundiff) undergo differentiation in response to retinoic acid (RA), while their progenitor states are partially maintained by fibroblast growth factors (FGFs). Sertoli valve (SV) is a region located at the terminal end of seminiferous tubule (ST) adjacent to the rete testis (RT), where the high density of Aundiff is constitutively maintained with the absence of active spermatogenesis. However, the molecular and cellular characteristics of SV epithelia still remain unclear. In this study, we first identified the region-specific AKT phosphorylation in the SV Sertoli cells and demonstrated non-cell autonomous specialization of Sertoli cells in the SV region by performing a Sertoli cell ablation/replacement experiment. The expression of Fgf9 was detected in the RT epithelia, while the exogenous administration of FGF9 caused ectopic AKT phosphorylation in the Sertoli cells of convoluted ST. Furthermore, we revealed the SV region-specific expression of Cyp26a1, which encodes an RA-degrading enzyme, and demonstrated that the increased RA levels in the SV region disrupt its pool of Aundiff by inducing their differentiation. Taken together, RT-derived FGFs and low levels of RA signaling contribute to the non-cell-autonomous regionalization of the SV epithelia and its local maintenance of Aundiff in the SV region.


Assuntos
Túbulos Seminíferos/metabolismo , Células de Sertoli/metabolismo , Tretinoína/metabolismo , Animais , Diferenciação Celular , Epitélio/fisiologia , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-kit/análise , Regeneração , Ácido Retinoico 4 Hidroxilase/genética , Ácido Retinoico 4 Hidroxilase/metabolismo , Túbulos Seminíferos/efeitos dos fármacos , Túbulos Seminíferos/crescimento & desenvolvimento , Células de Sertoli/fisiologia , Células de Sertoli/transplante , Transdução de Sinais , Espermatogênese , Tretinoína/farmacologia , Regulação para Cima
7.
Artigo em Inglês | MEDLINE | ID: mdl-33291280

RESUMO

Gender differences have been documented in the prevalence of psychological symptoms. Tic disorders and autism spectrum disorder (ASD) are more common in male clinical samples, while selective mutism and trichotillomania are more common in female clinical samples. In a review of 84 published case studies of Japanese children, this study explored gender differences in the prevalence of four categories of symptoms and expressions made in therapy for tics, selective mutism, autism spectrum disorder (ASD), and trichotillomania. Case studies were evaluated using both qualitative coding and statistical analysis. The findings were mostly consistent with epidemiological surveys and empirical research on adults. The gender differences in symptom prevalence and their expression could be summarized as differences in more direct aggression for boys versus indirect aggression for girls. The objective and progress in the therapy were to control impulsive energy for boys and to express energy for girls.


Assuntos
Transtorno do Espectro Autista , Caracteres Sexuais , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/terapia , Criança , Feminino , Humanos , Japão/epidemiologia , Masculino , Processos Psicoterapêuticos , Fatores Sexuais
8.
Cell Stem Cell ; 27(3): 396-412.e6, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32755548

RESUMO

Dermal fibroblasts exhibit considerable heterogeneity during homeostasis and in response to injury. Defining lineage origins of reparative fibroblasts and regulatory programs that drive fibrosis or, conversely, promote regeneration will be essential for improving healing outcomes. Using complementary fate-mapping approaches, we show that hair follicle mesenchymal progenitors make limited contributions to wound repair. In contrast, extrafollicular progenitors marked by the quiescence-associated factor Hic1 generated the bulk of reparative fibroblasts and exhibited functional divergence, mediating regeneration in the center of the wound neodermis and scar formation in the periphery. Single-cell RNA-seq revealed unique transcriptional, regulatory, and epithelial-mesenchymal crosstalk signatures that enabled mesenchymal competence for regeneration. Integration with scATAC-seq highlighted changes in chromatin accessibility within regeneration-associated loci. Finally, pharmacological modulation of RUNX1 and retinoic acid signaling or genetic deletion of Hic1 within wound-activated fibroblasts was sufficient to modulate healing outcomes, suggesting that reparative fibroblasts have latent but modifiable regenerative capacity.


Assuntos
Derme , Cicatrização , Cicatriz/patologia , Derme/patologia , Fibroblastos , Folículo Piloso , Humanos , Pele
9.
Development ; 147(13)2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32554530

RESUMO

In mammalian testis, contractile peritubular myoid cells (PMCs) regulate the transport of sperm and luminal fluid, while secreting growth factors and extracellular matrix proteins to support the spermatogonial stem cell niche. However, little is known about the role of testicular smooth muscle cells during postnatal testicular development. Here we report age-dependent expression of hypermethylated in cancer 1 (Hic1; also known as ZBTB29) in testicular smooth muscle cells, including PMCs and vascular smooth muscle cells, in the mouse. Postnatal deletion of Hic1 in smooth muscle cells led to their increased proliferation and resulted in dilatation of seminiferous tubules, with increased numbers of PMCs. These seminiferous tubules contained fewer Sertoli cells and more spermatogonia, and fibronectin was not detected in their basement membrane. The expression levels of genes encoding smooth muscle contractile proteins, Acta2 and Cnn1, were downregulated in the smooth muscle cells lacking Hic1, and the seminiferous tubules appeared to have reduced contractility. These data imply a role for Hic1 in determining the size of seminiferous tubules by regulating postnatal smooth muscle cell proliferation, subsequently affecting spermatogenesis in adulthood.


Assuntos
Fibronectinas/metabolismo , Miócitos de Músculo Liso/metabolismo , Testículo/metabolismo , Actinas/genética , Actinas/metabolismo , Animais , Fibronectinas/genética , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo
11.
Biol Reprod ; 100(6): 1648-1660, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30927418

RESUMO

Three-dimensional (3D) organoids can serve as an in vitro platform to study cell-cell interactions, tissue development, and toxicology. Development of organoids with tissue architecture similar to testis in vivo has remained a challenge. Here, we present a microwell aggregation approach to establish multicellular 3D testicular organoids from pig, mouse, macaque, and human. The organoids consist of germ cells, Sertoli cells, Leydig cells, and peritubular myoid cells forming a distinct seminiferous epithelium and interstitial compartment separated by a basement membrane. Sertoli cells in the organoids express tight junction proteins claudin 11 and occludin. Germ cells in organoids showed an attenuated response to retinoic acid compared to germ cells in 2D culture indicating that the tissue architecture of the organoid modulates response to retinoic acid similar to in vivo. Germ cells maintaining physiological cell-cell interactions in organoids also had lower levels of autophagy indicating lower levels of cellular stress. When organoids were treated with mono(2-ethylhexyl) phthalate (MEHP), levels of germ cell autophagy increased in a dose-dependent manner, indicating the utility of the organoids for toxicity screening. Ablation of primary cilia on testicular somatic cells inhibited the formation of organoids demonstrating an application to screen for factors affecting testicular morphogenesis. Organoids can be generated from cryopreserved testis cells and preserved by vitrification. Taken together, the testicular organoid system recapitulates the 3D organization of the mammalian testis and provides an in vitro platform for studying germ cell function, testicular development, and drug toxicity in a cellular context representative of the testis in vivo.


Assuntos
Técnicas de Cultura de Células/métodos , Organoides/citologia , Testículo/citologia , Alicerces Teciduais , Animais , Contagem de Células , Técnicas de Cultura de Células/instrumentação , Pré-Escolar , Dietilexilftalato/análogos & derivados , Dietilexilftalato/farmacologia , Humanos , Lactente , Macaca mulatta , Masculino , Camundongos , Organoides/fisiologia , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Espermatogônias/citologia , Espermatogônias/efeitos dos fármacos , Espermatogônias/fisiologia , Suínos , Alicerces Teciduais/química , Tretinoína/farmacologia
12.
Cell Stem Cell ; 24(1): 79-92.e6, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30581080

RESUMO

In many tissues, homeostasis is maintained by physical contact between stem cells and an anatomically defined niche. However, how stem cell homeostasis is achieved in environments where cells are motile and dispersed among their progeny remains unknown. Using murine spermatogenesis as a model, we find that spermatogenic stem cell density is tightly regulated by the supply of fibroblast growth factors (FGFs) from lymphatic endothelial cells. We propose that stem cell homeostasis is achieved through competition for a limited supply of FGFs. We show that the quantitative dependence of stem cell density on FGF dosage, the biased localization of stem cells toward FGF sources, and stem cell dynamics during regeneration following injury can all be predicted and explained within the framework of a minimal theoretical model based on "mitogen competition." We propose that this model provides a generic and robust mechanism to support stem cell homeostasis in open, or facultative, niche environments.


Assuntos
Fator 5 de Crescimento de Fibroblastos/fisiologia , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/fisiologia , Homeostase , Mitógenos/farmacologia , Espermatogênese , Espermatozoides/citologia , Células-Tronco/citologia , Animais , Diferenciação Celular , Autorrenovação Celular , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Espermatozoides/fisiologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/fisiologia
13.
Neuroscience ; 393: 226-235, 2018 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-30326292

RESUMO

Motor actions can be released much sooner than normal when the go-signal is of very high intensity (>100 dBa). Although statistical evidence from individual studies has been mixed, it has been assumed that sternocleidomastoid (SCM) muscle activity could be used to distinguish between two neural circuits involved in movement triggering. We summarized meta-analytically the available evidence for this hypothesis, comparing the difference in premotor reaction time (RT) of actions where SCM activity was elicited (SCM+ trials) by loud acoustic stimuli against trials in which it was absent (SCM- trials). We found ten studies, all reporting comparisons between SCM+ and SCM- trials. Our mini meta-analysis showed that premotor RTs are faster in SCM+ than in SCM- trials, but the effect can be confounded by the variability of the foreperiods employed. We present experimental data showing that foreperiod predictability can induce differences in RT that would be of similar size to those attributed to the activation of different neurophysiological pathways to trigger prepared actions. We discuss plausible physiological mechanisms that would explain differences in premotor RTs between SCM+ and SCM- trials.


Assuntos
Estimulação Acústica , Motivação/fisiologia , Movimento/fisiologia , Músculo Esquelético/fisiologia , Tempo de Reação/fisiologia , Estimulação Acústica/métodos , Adolescente , Adulto , Eletromiografia/métodos , Feminino , Humanos , Masculino , Músculos do Pescoço/fisiologia , Reflexo de Sobressalto/fisiologia , Adulto Jovem
14.
Neuroimage Clin ; 19: 716-726, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30009128

RESUMO

Introduction: Traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD) are risk factors for early onset of Alzheimer's disease (AD) and may accelerate the progression rate of AD pathology. As amyloid-beta (Aß) plaques are a hallmark of AD pathology, we hypothesized that TBI and PTSD might increase Aß accumulation in the brain. Methods: We examined PET and neuropsychological data from Vietnam War veterans compiled by the US Department of Defense Alzheimer's Disease Neuroimaging Initiative, to examine the spatial distribution of Aß in male veterans' who had experienced a TBI and/or developed PTSD. Subjects were classified into controls, TBI only, PTSD only, and TBI with PTSD (TBI_PTSD) groups and data were analyzed using both voxel-based and ROI-based approaches. Results: Compared to controls, all three clinical groups showed a pattern of mainly increased referenced standard uptake values (SUVR) for the amyloid tracer [18F]-AV45 PET, with rank order PTSD > TBI_PTSD > TBI > Control, and same rank order was seen in the deficits of cognitive functions. SUVR increase was observed in widespread cortical regions of the PTSD group; in white matter of the TBI_PTSD group; and cerebellum and precuneus area of the TBI group, in contrast with controls. The [18F]-AV45 SUVR correlated negatively with cerebrospinal fluid (CSF) amyloid levels and positively with the CSF tau concentrations. Conclusion: These results suggest that both TBI and PTSD are substantial risk factors for cognition decline and increased Aß deposition resembling that in AD. In addition, both PTSD and TBI_PTSD have a different pathways of Aß accumulation.


Assuntos
Peptídeos beta-Amiloides/líquido cefalorraquidiano , Lesões Encefálicas Traumáticas/diagnóstico , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Idoso , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/patologia , Diagnóstico Diferencial , Progressão da Doença , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/patologia , Proteínas tau/líquido cefalorraquidiano
15.
Mol Reprod Dev ; 85(3): 262-270, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29393534

RESUMO

In mouse testes, Sertoli cells support the continuous process of spermatogenesis, which is dependent on seminiferous epithelial cycles along the longitudinal axis of the seminiferous tubule. Sertoli cell function is modulated partly by local cytokines and/or growth factors derived from adjacent tissues such as blood vessels, macrophages, rete testis, etc. However, the spatial activation patterns by local signals in vivo remain unclear. In this study, we focused on Signal Transducers and Activators of Transcription (STAT) signaling in Sertoli cells, because STAT is a major crucial cytokine transducer for somatic cyst cell regulation in Drosophila testis niches. In mouse testes, STAT3 was ubiquitously expressed in Sertoli cells throughout the seminiferous tubules. Phosphorylated STAT3 (p-STAT3) was predominantly observed in the Sertoli cells within the valve-like structure adjacent to the rete testis (i.e., the Sertoli valve [SV]) in the terminal segment of the proximal seminiferous tubules. In the distal seminiferous tubules with active spermatogenesis, most Sertoli cells were negative for anti-p-STAT3 staining. Albeit rarely, a small patch of several p-STAT3-positive Sertoli cells was detected frequently in seminiferous epithelial cycle stages I-VI. Such p-STAT3-positive ratios in the convoluted seminiferous epithelia were significantly increased in germ cell-less testes than in the wild-type testes, but with considerably lower ratios than in the SV region. These findings imply that regionally distinct patterns of STAT3 phosphorylation in the Sertoli cells depend on either location or spermatogenic activity in normal healthy testes in vivo, highlighting a novel entry point to understanding STAT signaling in mammalian spermatogenesis.


Assuntos
Fator de Transcrição STAT3/metabolismo , Epitélio Seminífero/metabolismo , Células de Sertoli/metabolismo , Espermatogênese/fisiologia , Testículo/metabolismo , Animais , Masculino , Camundongos , Especificidade de Órgãos , Fosforilação
16.
Reproduction ; 154(2): 135-143, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28559472

RESUMO

USP9X (ubiquitin-specific peptidase 9, X chromosome) is the mammalian orthologue of Drosophila deubiquitinase fat facets that was previously shown to regulate the maintenance of the germ cell lineage partially through stabilizing Vasa, one of the widely conserved factors crucial for gametogenesis. Here, we demonstrate that USP9X is expressed in the gonocytes and spermatogonia in mouse testes from newborn to adult stages. By using Vasa-Cre mice, germ cell-specific conditional deletion of Usp9x from the embryonic stage showed no abnormality in the developing testes by 1 week and no appreciable defects in the undifferentiated and differentiating spermatogonia at postnatal and adult stages. Interestingly, after 2 weeks, Usp9x-null spermatogenic cells underwent apoptotic cell death at the early spermatocyte stage, and then, caused subsequent aberrant spermiogenesis, which resulted in a complete infertility of Usp9x conditional knockout male mice. These data provide the first evidence of the crucial role of the spermatogonial USP9X during transition from the mitotic to meiotic phases and/or maintenance of early meiotic phase in Usp9x conditional knockout testes.


Assuntos
Endopeptidases/metabolismo , Fertilidade , Infertilidade Masculina/enzimologia , Espermatogênese , Espermatogônias/enzimologia , Testículo/enzimologia , Fatores Etários , Animais , Apoptose , Endopeptidases/deficiência , Endopeptidases/genética , Genótipo , Infertilidade Masculina/genética , Infertilidade Masculina/fisiopatologia , Masculino , Meiose , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Transdução de Sinais , Espermatogônias/patologia , Testículo/patologia , Testículo/fisiopatologia , Ubiquitina Tiolesterase
17.
Data Brief ; 8: 1255-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27547806

RESUMO

This article contains the data related to the research article "in vivo dynamics of GFRα1-positive spermatogonia stimulated by GDNF signals using a bead transplantation assay" (Uchida et al., 2016) [1]. A novel transplantation assay of growth factor-soaked beads into the mammalian testicular interstitium was developed, in order to examine the effects of various soluble factors on in vivo dynamics of the spermatogonia including spermatogonial stem cells (SSC). Here we provide the image data of GFRα1-positive stem/progenitor spermatogonia in mouse seminiferous tubules near the beads soaked in GDNF (glial cell-derived neurotrophic factor), one of the SSC niche factors. The data provide various phenotypes of GFRα1-positive spermatogonia induced by bead-derived GDNF signals, which are useful to understand the active state of GFRα1-positive stem/progenitor spermatogonia in vivo.

18.
Biochem Biophys Res Commun ; 476(4): 546-552, 2016 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-27255992

RESUMO

In mouse testes, spermatogonial stem cells (SSCs), a subpopulation of GFRα1 (GDNF family receptor-α1)-positive spermatogonia, are widely distributed along the convoluted seminiferous tubules. The proliferation and differentiation of the SSCs are regulated in part by local expression of GDNF (glial cell-derived neurotorphic factor), one of major niche factors for SSCs. However, the in vivo dynamics of the GDNF-stimulated GFRα1-positive spermatogonia remains unclear. Here, we developed a simple method for transplanting DiI-labeled and GDNF-soaked beads into the mouse testicular interstitium. By using this method, we examined the dynamics of GFRα1-positive spermatogonia in the tubular walls close to the transplanted GDNF-soaked beads. The bead-derived GDNF signals were able to induce the stratified aggregate formation of GFRα1-positive undifferentiated spermatogonia by day 3 post-transplantation. Each aggregate consisted of tightly compacted Asingle and marginal Apaired-Aaligned GFRα1-positive spermatogonia and was surrounded by Aaligned GFRα1-negative spermatogonia at more advanced stages. These data not only provide in vivo evidence for the inductive roles of GDNF in forming a rapid aggregation of GFRα1-positive spermatogonia but also indicate the usefulness of this in vivo assay system of various growth factors for the stem/progenitor spermatogonia in mammalian spermatogenesis.


Assuntos
Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Espermatogônias/metabolismo , Animais , Agregação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Implantes de Medicamento/administração & dosagem , Fator Neurotrófico Derivado de Linhagem de Célula Glial/administração & dosagem , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Transdução de Sinais , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Espermatogônias/efeitos dos fármacos , Nicho de Células-Tronco/efeitos dos fármacos , Testículo/citologia , Testículo/efeitos dos fármacos , Testículo/metabolismo
19.
ORL J Otorhinolaryngol Relat Spec ; 71 Suppl 1: 67-70, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20185951

RESUMO

OBJECTIVE: To locate fibroblast growth factor receptor (FGFRs) 1-4 in human chronic tympanic membrane (TM) perforation. METHODS: A sample of human chronic TM perforation was harvested during myringoplasty. The sample was immediately fixed in 4% paraformaldehyde and embedded in OCT compound. Immunohistochemistry was performed with FGFR 1-4 polyclonal antibodies. RESULTS: FGFRs 1-4 were strongly and weakly expressed in the epidermal and mucosal layer of the TM perforation, respectively. CONCLUSIONS: As it is impossible to perform quantitative analysis based on the fluorescence intensity of each immunoreactivity, the presence of FGFRs 1-4 in the human chronic TM perforation is shown. The expressions of FGFRs 1-4 indicated that the clinical use of bFGF agent is useful for myringoplasty.


Assuntos
Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Perfuração da Membrana Timpânica/metabolismo , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Miringoplastia , Perfuração da Membrana Timpânica/cirurgia
20.
Intern Med ; 47(10): 925-31, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18480576

RESUMO

OBJECTIVE: The molecular basis for the antithrombin (AT) deficiency and dilated cardiomyopathy (DCM) combined in a Japanese patient was investigated. METHODS: We analyzed candidate genes -SERPINC1 for AT deficiency, and TNNT2 and LMNA for DCM. In addition, we examined the characteristics of recombinant mutant AT and evaluated the LMNA mutation associated with DCM by molecular modeling. RESULTS: Genome sequencing of SERPINC1 revealed a C-to-A transversion in exon 6 that resulted in a p.Pro439Thr mutation of AT, which was previously reported as a pleiotropic effect type II AT deficiency (AT Budapest5). However, expression experiments with recombinant 439Thr-AT showed normal heparin affinity, slightly reduced secretion, and low specific activity, which suggested that this mutation exhibits an intermediate feature of type I and type II AT deficiencies. In a survey of gene abnormalities causing DCM, we found no causative gene defect in TNNT2; however, we identified a G-to-C transversion in LMNA that resulted in a novel p.Asp357His mutation in lamin A/C. This acidic-to-basic residue substitution might have impaired the head-to-tail association of two lamin dimers leading to DCM. Further, we identified both SERPINC1 and LMNA mutations in the patient's daughter and son, both of whom had AT deficiency. These data suggested that a p.Pro439Thr mutation in SERPINC1 and a p.Asp357His mutation in LMNA might have cosegregated in this family, associated with AT deficiency and DCM, respectively. CONCLUSIONS: We identified missense mutations in SERPINC1 and LMNA genes to be associated with AT deficiency and DCM, respectively, which might have cosegregated in the family of the patient.


Assuntos
Deficiência de Antitrombina III/genética , Antitrombina III/genética , Cardiomiopatia Dilatada/genética , Predisposição Genética para Doença/genética , Lamina Tipo A , Adulto , Deficiência de Antitrombina III/complicações , Infarto Encefálico/etiologia , Infarto Encefálico/genética , Cardiomiopatia Dilatada/complicações , Feminino , Heterozigoto , Humanos , Lamina Tipo A/deficiência , Lamina Tipo A/genética , Masculino , Pessoa de Meia-Idade , Linhagem
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