“I Don’t Fit into a Single Type”: A Trait Model and Scale of Game Playing Preferences

SummaryThe decision by germ cells to differentiate and undergo either oogenesis or spermatogenesis takes place during embryonic development and Nanos plays an important role in this process. The present study was designed to investigate the expression patterns in rat of Nanos2-homologue protein in primordial germ cells (PGCs) over different embryonic developmental days as well as in spermatogonial stem cells (SSCs). Embryos from three different embryonic days (E8.5, E10.5, E11.5) and SSCs were isolated and used to detect Nanos2-homologue protein using immunocytochemistry, western blotting, reverse transcription polymerase chain reaction (RT-PCR) and flow cytometry. Interestingly, Nanos2 expression was detected in PGCs at day E11.5 onwards and up to colonization of PGCs in the genital ridge of fetal gonads. No Nanos2 expression was found in PGCs during early embryonic days (E8.5 and 10.5). Furthermore, immunohistochemical and immunofluorescence data revealed that Nanos2 expression was restricted within a subpopulation of undifferentiated spermatogonia (As, single type A SSCs and Apr, paired type A SSCs). The same results were confirmed by our western blot and RT-PCR data, as Nanos2 protein and transcripts were detected only in PGCs from day E11.5 and in undifferentiated spermatogonia (As and Apr). Furthermore, Nanos2-positive cells were also immunodetected and sorted using flow cytometry from the THY1-positive SSCs population, and this strengthened the idea that these cells are stem cells. Our findings suggested that stage-specific expression of Nanos2 occurred on different embryonic developmental days, while during the postnatal period Nanos2 expression is restricted to As and Apr SSCs.

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Meagre Argyrosomus regius (Asso, 1801) Stem Spermatogonia: Histological Characterization, Immunostaining, In Vitro Proliferation, and Cryopreservation

Animals ◽

10.3390/ani10050851 ◽

2020 ◽

Vol 10 (5) ◽

pp. 851 ◽

Cited By ~ 2

Author(s):

Rosa Zupa ◽

Nicola A. Martino ◽

Giuseppina Marzano ◽

Maria E. Dell’Aquila ◽

Aldo Corriero

Keyword(s):

Gradient Centrifugation ◽

Type A ◽

Single Type ◽

In Vitro Proliferation ◽

Argyrosomus Regius ◽

In Captivity ◽

Active Proliferation ◽

Aquaculture Production ◽

Type A Spermatogonia

The meagre, Argyrosomus regius, is a valued fish species of which aquaculture production might be supported by the development of a stem germ cell xenotransplantation technology. Meagre males were sampled at a fish farm in the Ionian Sea (Italy) at the beginning and end of the reproductive season. Small and large Type A undifferentiated spermatogonia were histologically identified in the germinal epithelium. Among the tested stemness markers, anti-oct4 and anti-vasa antibodies labeled cells likely corresponding to the small single Type A spermatogonia; no labeling was obtained with anti-GFRA1 and anti-Nanos2 antibodies. Two types of single A spermatogonia were purified via density gradient centrifugation of enzymatically digested testes. Testes from fish in active spermatogenesis resulted in a more efficient spermatogonial stem cell (SSC) yield. After cell seeding, meagre SSCs showed active proliferation from Day 7 to Day 21 and were cultured up to Day 41. After cryopreservation in dimethyl-sulfoxide-based medium, cell viability was 28.5%. In conclusion, these results indicated that meagre SSCs could be isolated, characterized, cultured in vitro, successfully cryopreserved, and used after thawing. This is a first step towards the development of a xenotransplantation technology that might facilitate the reproduction of this valuable species in captivity.

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Fsh Stimulates Spermatogonial Proliferation and Differentiation in Zebrafish via Igf3

Endocrinology ◽

10.1210/en.2015-1157 ◽

2015 ◽

Vol 156 (10) ◽

pp. 3804-3817 ◽

Cited By ~ 66

Author(s):

Rafael Henrique Nóbrega ◽

Roberto Daltro Vidal de Souza Morais ◽

Diego Crespo ◽

Paul P. de Waal ◽

Luiz Renato de França ◽

...

Keyword(s):

Mitotic Index ◽

Germ Line ◽

Type A ◽

Single Type ◽

Dependent Manner ◽

Independent Manner ◽

Proliferation And Differentiation ◽

Igf Receptor ◽

Receptor Inhibitor ◽

Spermatogonial Proliferation

Growth factors modulate germ line stem cell self-renewal and differentiation behavior. We investigate the effects of Igf3, a fish-specific member of the igf family. Fsh increased in a steroid-independent manner the number and mitotic index of single type A undifferentiated spermatogonia and of clones of type A differentiating spermatogonia in adult zebrafish testis. All 4 igf gene family members in zebrafish are expressed in the testis but in tissue culture only igf3 transcript levels increased in response to recombinant zebrafish Fsh. This occurred in a cAMP/protein kinase A-dependent manner, in line with the results of studies on the igf3 gene promoter. Igf3 protein was detected in Sertoli cells. Recombinant zebrafish Igf3 increased the mitotic index of type A undifferentiated and type A differentiating spermatogonia and up-regulated the expression of genes related to spermatogonial differentiation and entry into meiosis, but Igf3 did not modulate testicular androgen release. An Igf receptor inhibitor blocked these effects of Igf3. Importantly, the Igf receptor inhibitor also blocked Fsh-induced spermatogonial proliferation. We conclude that Fsh stimulated Sertoli cell production of Igf3, which promoted via Igf receptor signaling spermatogonial proliferation and differentiation and their entry into meiosis. Because previous work showed that Fsh also released spermatogonia from an inhibitory signal by down-regulating anti-Müllerian hormone and by stimulating androgen production, we can now present a model, in which Fsh orchestrates the activity of stimulatory (Igf3, androgens) and inhibitory (anti-Müllerian hormone) signals to promote spermatogenesis.

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Apical H+/base transporters mediating bicarbonate absorption and pHi regulation in the OMCD

AJP Renal Physiology ◽

10.1152/ajprenal.0241.2001 ◽

2002 ◽

Vol 283 (5) ◽

pp. F1098-F1104 ◽

Cited By ~ 15

Author(s):

Kay-Pong Yip ◽

Shuichi Tsuruoka ◽

George J. Schwartz ◽

Ira Kurtz

Keyword(s):

Recovery Rate ◽

Collecting Duct ◽

Type A ◽

Single Type ◽

Minor Role ◽

Intercalated Cells ◽

Confocal Fluorescence ◽

Medullary Collecting Duct ◽

A Minor

The outer medullary collecting duct (OMCD) plays an important role in mediating transepithelial HCO[Formula: see text] transport ([Formula: see text]) and urinary acidification. HCO[Formula: see text] absorption by type A intercalated cells in the OMCD inner stripe (OMCDis) segment is thought to by mediated by an apical vacuolar H+-ATPase and H+-K+-ATPase coupled to a basolateral Cl−-HCO[Formula: see text] exchanger (AE1). Besides these Na+-independent transporters, previous studies have shown that OMCDis type A intercalated cells have an apical electroneutral EIPA-sensitive, DIDS-insensitive Na+-HCO[Formula: see text] cotransporter (NBC3); a basolateral Na+/H+ antiporter; and a basolateral Na+-K+-ATPase. In this study, we reexamined the Na+ dependence of transepithelial Na+ transport in the OMCDis and determined the role of apical NBC3 in intracellular (pHi) regulation in OMCDis type A intercalated cells. Control tubules absorbed HCO[Formula: see text] at a rate of ∼13 pmol · min−1 · mm−1. Lowering luminal Na+ from 140 to 40 mM decreased[Formula: see text] by ∼15% without a change in transepithelial potential ( V te). Furthermore, 50 μM EIPA (lumen) also decreased [Formula: see text] by ∼13% without a change in V te. The effect of lowering luminal Na+ and adding EIPA were not additive. These results demonstrate that[Formula: see text] in the OMCDis is in part Na+ dependent. In separate experiments, the pHi recovery rate after an NH[Formula: see text] prepulse was monitored in single type A intercalated cells with confocal fluorescence microscopy. The pHi recovery rate was ∼0.21 pH/min in Na+-containing solutions and decreased to ∼0.16 pH/min with EIPA (50 μM, lumen). In tubules perfused/bathed without Na+, luminal Na+ addition resulted in a pHi recovery rate of ∼0.36 pH/min, whereas the Na+-independent recovery rate was ∼0.16 pH/min. EIPA (50 μM, lumen) decreased the Na+-dependent pHirecovery rate to ∼0.07 pH/min. The Na+-independent recovery rate was decreased to ∼0.06 pH/min by bafilomycin (10 nM, lumen) and to ∼0.10 pH/min using Schering 28080 (10 μM, lumen). These findings indicate that NBC3 contributes to pHiregulation in OMCDis type A intercalated cells and plays only a minor role in mediating[Formula: see text] in the OMCDis.

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Combating Corruption in Asian Countries: Learning from Success & Failure

Daedalus ◽

10.1162/daed_a_00511 ◽

2018 ◽

Vol 147 (3) ◽

pp. 202-215

Author(s):

Jon S.T. Quah

Keyword(s):

Hong Kong ◽

Type A ◽

The Philippines ◽

Single Type ◽

Type B ◽

Asian Countries ◽

Political Will ◽

Policy Makers ◽

Hong Kong Sar

With widespread corruption in many Asian countries, Singapore and Hong Kong SAR have proved exceptions: their governments’ strong political will and reliance on single “Type A” anticorruption agencies (ACAs) have effectively and impartially enforced anticorruption laws. By contrast, the governments in China, India, and the Philippines have failed to minimize corruption due to weak political will and reliance on multiple ineffective and poorly resourced “Type B” ACAs. This essay draws on the experiences of these five countries to identify four lessons for policy-makers to enhance the effectiveness of their ACAs.

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Thyroid Hormone Stimulates the Proliferation of Sertoli Cells and Single Type A Spermatogonia in Adult Zebrafish (Danio rerio) Testis

Endocrinology ◽

10.1210/en.2013-1308 ◽

2013 ◽

Vol 154 (11) ◽

pp. 4365-4376 ◽

Cited By ~ 48

Author(s):

R. D. V. S. Morais ◽

R. H. Nóbrega ◽

N. E. Gómez-González ◽

R. Schmidt ◽

J. Bogerd ◽

...

Keyword(s):

Gene Expression ◽

Tissue Culture ◽

Thyroid Hormone ◽

Sertoli Cells ◽

Connexin 43 ◽

Type A ◽

Single Type ◽

Mrna Levels ◽

Adult Zebrafish ◽

Androgen Sensitivity

Thyroid hormones participate in regulating growth and homeostatic processes in vertebrates, including development and adult functioning of the reproductive system. Here we report a new stimulatory role of thyroid hormone on the proliferation of Sertoli cells (SCs) and single, type A undifferentiated spermatogonia (Aund) in adult zebrafish testes. A role for T3 in zebrafish testis is suggested by in situ hybridization studies, which localized thyroid receptor α (thrα) in SCs and the β (thrβ) mRNA in Sertoli and Leydig cells. Using a primary zebrafish testis tissue culture system, the effect of T3 on steroid release, spermatogenesis, and the expression of selected genes was evaluated. Basal steroid release and Leydig cell gene expression did not change in response to T3. However, in the presence of FSH, T3 potentiated gonadotropin-stimulated androgen release as well as androgen receptor (ar) and 17α-hydroxylase/17,20 lyase (cyp17a1) gene expression. Moreover, T3 alone stimulated the proliferation of both SCs and Aund, potentially resulting in newly formed spermatogonial cysts. Additional tissue culture studies demonstrated that Igf3, a new, gonad-specific member of the IGF family, mediated the stimulatory effect of T3 on the proliferation of Aund and SCs. Finally, T3 induced changes in connexin 43 mRNA levels in the testis, a known T3-responsive gene. Taken together, our studies suggest that T3 expands the population of SCs and Aund involving Igf signaling and potentiates gonadotropin-stimulated testicular androgen production as well as androgen sensitivity.

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Hope, exploration, and equilibrated action schemes

Behavioral and Brain Sciences ◽

10.1017/s0140525x18001863 ◽

2019 ◽

Vol 42 ◽

Cited By ~ 2

Author(s):

Davood G. Gozli ◽

Ci Jun Gao

Keyword(s):

Single Type ◽

Reward Seeking ◽

Stable Scheme

AbstractThe concepts want, hope, and exploration cannot be organized in relation to a single type of motive (e.g., motive for food). They require, in addition, the motive for acquiring and maintaining a stable scheme that enables reward-directed activity. Facing unpredictability, the animal has to seek not only reward, but also a new equilibrated state within which reward seeking is possible.

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Biological and Morphological Studies on Low-Leukemia-Strain Mice with Hodgkin's-Like Neoplasia Induced by Serial Cell-Free Transmission of Leukemic Organs of SJL/J Strain Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100792 ◽

1968 ◽

Vol 26 ◽

pp. 210-211

Author(s):

S. Fujinaga ◽

K. Maruyama ◽

C.W. Williams ◽

K. Sekhri ◽

L. Dmochowski

Keyword(s):

Tissue Culture ◽

Type A ◽

Reticulum Cell ◽

Type B ◽

Viral Origin ◽

Serial Transfer ◽

Strain Mouse ◽

Morphological Studies ◽

Cell Neoplasm ◽

Free Material

Yumoto and Dmochowski (Cancer Res.27, 2098 (1967)) reported the presence of mature and immature type C leukemia virus particles in leukemic organs and tissues such as lymph nodes, spleen, thymus, liver, and kidneys of SJL/J strain mice with Hodgki's-like disease or reticulum cell neoplasm (type B). In an attempt to ascertain the possibility that this neoplasia may be of viral origin, experiments with induction and transmission of this neoplasm were carried out using cell-free extracts of leukemic organs from an SJL/J strain mouse with spontaneous disease.It has been possible to induce the disease in low-leukemia BALB/c and C3HZB strain mice and serially transfer the neoplasia by cell-free extracts of leukemic organs of these mice. Histological examination revealed the neoplasia to be of either reticulum cell-type A or type B. Serial transfer is now in its fifth passage. In addition leukemic spleen from another SJL/J strain mouse with spontaneous reticulum cell neoplasm (type A) was set up in tissue culture and is now in its 141st serial passage in vitro. Preliminary results indicate that cell-free material of 39th tissue culture passage can reproduce neoplasia in BALB/c mice.

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Hepatitis A Antigen in Liver, Bile and Stool

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115328 ◽

1975 ◽

Vol 33 ◽

pp. 340-341

Author(s):

D.R. Jackson ◽

J.H. Hoofnagle ◽

A.N. Schulman ◽

J.L. Dienstag ◽

R.H. Purcell ◽

...

Keyword(s):

Hepatitis A ◽

Liver Enzymes ◽

Hepatitis A Virus ◽

Type A ◽

Initial Study ◽

Virus Like Particle ◽

Elevated Liver Enzymes ◽

Ag Particles ◽

Ag Particle ◽

Human Stool

Using immune electron microscopy Feinstone et. al. demonstrated the presence of a 27 nm virus-like particle in acute-phase stools of patients with viral hepatitis, type A, These hepatitis A antigen (HA Ag) particles were aggregated by convalescent serum from patients with type A hepatitis but not by pre-infection serum. Subsequently Dienstag et. al. and Maynard et. al. produced acute hepatitis in chimpanzees by inoculation with human stool containing HA Ag. During the early acute disease, virus like particles antigenically, morphologically and biophysically identical to the human HA Ag particle were found in chimpanzee stool. Recently Hilleman et. al. have described similar particles in liver and serum of marmosets infected with hepatitis A virus (HAV). We have investigated liver, bile and stool from chimpanzees and marmosets experimentally infected with HAV. In an initial study, a chimpanzee (no.785) inoculated with HA Ag-containing stool developed elevated liver enzymes 21 days after exposure.

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Detection of Viral Antigens in Mouse and Rat Tumor Cells by Immunoelectron Microscopy Following Periodate-Lysine-Paraformaldehyde (PLP) Fixation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009124x ◽

1976 ◽

Vol 34 ◽

pp. 252-253

Author(s):

Y. Ohtsuki ◽

G. Seman ◽

J. M. Bowen ◽

M. Scanlon ◽

L. Dmochowski

Keyword(s):

Immunoelectron Microscopy ◽

Mammary Tumor ◽

Type A ◽

Rabbit Serum ◽

Virus Particles ◽

Viral Antigens ◽

Culture Cells ◽

Mouse Mammary Tumor ◽

Tumor Virus ◽

Immunoperoxidase Labeling

Recently, periodate-lysine-paraformaldehyde (PLP) fixation was reported for immunoelectron microscopy (1). In PLP fixation, carbohydrates are oxidized by periodate and cross-linked by lysine; paraformaldehyde stabilizes proteins and lipids. By using PLP fixation, intracytoplasmic type A viral antigens have been previously demonstrated by immunoperoxidase labeling (2). In the present study, PLP fixation has been applied for the detection of the same antigens in mouse mammary tumor culture cells by both immunoferritin and immunoperoxidase methods. Rabbit anti-intracytoplasmic type A virus serum (anti-A), kindly provided by Dr. M. Muller (3), rabbit anti-strain A mouse mammary tumor virus (anti-MMTV) and preimmune rabbit serum as control were used to detect viral antigens in cells of C3H/HeJ strain mouse mammary tumor culture. Attempts have been also made to demonstrate peroxidase labeling of type C virus particles in frozen sections of an SD-MSV-induced NZB rat bone tumor tissue by rabbit anti-MuLV serum.

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