scholarly journals Sex Differentiation in Amphibians: Effect of Temperature and Its Influence on Sex Reversal

2021 ◽  
pp. 1-11
Author(s):  
Adrián Ruiz-García ◽  
Álvaro S. Roco ◽  
Mónica Bullejos
Keyword(s):  
Sexual Differentiation ◽  
Sex Differentiation ◽  
Environmental Contaminants ◽  
Natural Populations ◽  
Sex Reversal ◽  
The Other ◽  
Effect Of Temperature ◽  
Amphibian Species ◽  
Expected Increase

The role of environmental factors in sexual differentiation in amphibians is not new. The effect of hormones or hormone-like compounds is widely demonstrated. However, the effect of temperature has traditionally been regarded as something anecdotal that occurs in extreme situations and not as a factor to be considered. The data currently available reveal a different situation. Sexual differentiation in some amphibian species can be altered even by small changes in temperature. On the other hand, although not proven, it is possible that temperature is related to the appearance of sex-reversed individuals in natural populations under conditions unrelated to environmental contaminants. According to this, temperature, through sex reversal (phenotypic sex opposed to genetic sex), could play an important role in the turnover of sex-determining genes and in the maintenance of homomorphic sex chromosomes in this group. Accordingly, and given the expected increase in global temperatures, growth and sexual differentiation in amphibians could easily be affected, altering the sex ratio in natural populations and posing major conservation challenges for a group in worldwide decline. It is therefore particularly urgent to understand the mechanism by which temperature affects sexual differentiation in amphibians.

Igf3 is essential for ovary differentiation in zebrafish†

2020 ◽  
Author(s):  
Yuxin Xie ◽  
Duo Huang ◽  
Lianhe Chu ◽  
Yun Liu ◽  
Xiao Sun ◽  
...  
Keyword(s):  
Sexual Differentiation ◽  
Gene Knockout ◽  
Sex Differentiation ◽  
Sex Reversal ◽  
Estrogen Signaling ◽  
Differential Expression Pattern ◽  
Male Sex ◽  
In Vitro Treatment

Abstract Zebrafish gonadal sexual differentiation is an important but poorly understood subject. Previously, we have identified a novel Igf named Igf3 in teleosts. The importance of Igf3 in oocyte maturation and ovulation has been recently demonstrated by us in zebrafish. In this study, we have further found the essential role of Igf3 in gonadal sexual differentiation of zebrafish. A differential expression pattern of igf3 between ovary and testis during sex differentiation (higher level in ovary than in testis) was found in zebrafish. An igf3 knockout zebrafish line was established using TALENs-mediated gene knockout technique. Intriguingly, all igf3 homozygous mutants were males due to the female-to-male sex reversal occurred during sex differentiation. Further analysis showed that Igf3 did not seem to affect the formation of so-called juvenile ovary and oocyte-like germ cells. Oocyte development was arrested at primary growth stage, and the ovary was gradually sex-reversed to testis before 60 dpf. Such sex reversal was likely due to decreased germ cell proliferation by suppressing PI3K/Akt pathway in early ovaries of igf3 mutants. Estrogen is considered as a master regulator in fish sex differentiation. Here, we found that igf3 expression could be up-regulated by estrogen in early stages of ovarian follicles as evidenced in in vitro treatment assays and cyp19a1a mutant zebrafish, and E2 failed to rescue the defects of igf3 mutants in ovarian development, suggesting that Igf3 may serve as a downstream factor of estrogen signaling in sex differentiation. Taken together, we demonstrated that Igf3 is essential for ovary differentiation in zebrafish.

scholarly journals Müllerian Inhibiting Substance in the Caudate Amphibian Pleurodeles waltl

Endocrinology ◽  
2013 ◽  
Vol 154 (10) ◽  
pp. 3931-3936 ◽  
Author(s):  
Imane Al-Asaad ◽  
Dominique Chardard ◽  
Nathalie di Clemente ◽  
Jean-Yves Picard ◽  
Hélène Dumond ◽  
...  
Keyword(s):  
Sex Differentiation ◽  
Amphibian Species ◽  
Müllerian Inhibiting Substance ◽  
Gonad Differentiation ◽  
Key Factor ◽  
Mullerian Ducts ◽  
Pleurodeles Waltl ◽  
First Time ◽  
Mullerian Inhibiting Substance

Müllerian inhibiting substance (MIS, also known as anti-Müllerian hormone), is a key factor of male sex differentiation in vertebrates. In amniotes, it is responsible for Müllerian duct regression in male embryos. In fish, despite the absence of Müllerian ducts, MIS is produced and controls germ cell proliferation during gonad differentiation. Here we show for the first time the presence of MIS in an amphibian species, Pleurodeles waltl. This is very astonishing because in caudate amphibians, Müllerian ducts do not regress in males. Phylogenetic analysis of MIS P. waltl ortholog revealed that the deduced protein segregates with MIS from other vertebrates and is clearly separated from other TGF-β family members. In larvae, MIS mRNA was expressed at higher levels in the developing testes than in the ovaries. In the testis, MIS mRNA expression was located within the lobules that contain Sertoli cells. Besides, expression of MIS was modified in the case of sex reversal: it increased after masculinizing heat treatment and decreased after estradiol feminizing exposure. In addition to the data obtained recently in the fish medaka, our results suggest that the role of MIS on Müllerian ducts occurred secondarily during the course of evolution.

The effect of temperature on kernel development in cereals

1978 ◽  
Vol 29 (2) ◽  
pp. 205 ◽  
Author(s):  
SI Chowdhury ◽  
IF Wardlaw
Keyword(s):  
Flag Leaf ◽  
Temperature Response ◽  
Net Photosynthesis ◽  
Kernel Weight ◽  
The Other ◽  
Effect Of Temperature ◽  
Kernel Development ◽  
Preliminary Examination ◽  
Small Change

A study has been made of the effect of temperature on kernel development and mature kernel weight of three contrasting cereals: wheat, rice and sorghum. Wheat and sorghum showed clear and well-separated optimum temperatures for individual kernel dry weights of 15/10° and 27/22°C respectively, while rice showed a relatively small change in weight over temperatures ranging from 21/16° to 30/25°. Rice kernel development was less affected by temperature extremes than sorghum, but was more sensitive to low temperature than wheat. At the lower temperatures (21/16°) the rate of development of individual kernels was greater in wheat than in the other species, while in sorghum, which had a more marked temperature response, the rate of kernel development was greater than in the other cereals at the higher temperatures (30/25°). A preliminary analysis of barley suggests that kernel development in this cereal responds to temperature in a similar way to wheat. Measurements of net photosynthesis of the flag leaf blade and ear of each cereal, at intervals after anthesis, suggested that at the completion of kernel development a source of carbohydrate was still available for continued development at all temperatures. A preliminary examination was carried out on the role of respiration and of translocation in limiting kernel development at high temperatures.

Plasma Levels of Protein S, Protein C, and Factor X: Effects of Sex, Hormonal State and Age

1995 ◽  
Vol 74 (05) ◽  
pp. 1271-1275 ◽  
Author(s):  
C M A Henkens ◽  
V J J Bom ◽  
W van der Schaaf ◽  
P M Pelsma ◽  
C Th Smit Sibinga ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Postmenopausal Women ◽  
Protein C ◽  
Blood Donors ◽  
Premenopausal Women ◽  
Protein S ◽  
The Other ◽  
Factor X ◽  
Normal Ranges

SummaryWe measured total and free protein S (PS), protein C (PC) and factor X (FX) in 393 healthy blood donors to assess differences in relation to sex, hormonal state and age. All measured proteins were lower in women as compared to men, as were levels in premenopausal women as compared to postmenopausal women. Multiple regression analysis showed that both age and subgroup (men, pre- and postmenopausal women) were of significance for the levels of total and free PS and PC, the subgroup effect being caused by the differences between the premenopausal women and the other groups. This indicates a role of sex-hormones, most likely estrogens, in the regulation of levels of pro- and anticoagulant factors under physiologic conditions. These differences should be taken into account in daily clinical practice and may necessitate different normal ranges for men, pre- and postmenopausal women.

On the role of the dispute between "non-possessors" and "Josephites" in the culture of Moscow's prediction

1998 ◽  
pp. 61-62
Author(s):  
N. S. Jurtueva
Keyword(s):  
The Other ◽  
Moral Transformation ◽  
15Th Century ◽  
The Future ◽  
Secular Power

In the XIV century. centripetal tendencies began to appear in the Moscow principality. Inside the Russian church, several areas were distinguished. Part of the clergy supported the specificobar form. The other understood the need for transformations in society. As a result, this led to a split in the Russian church in the 15th century for "non-possessors" and "Josephites". The former linked the fate of the future with the ideology of hesychasm and its moral transformation, while the latter sought support in alliance with a strong secular power.

From Container to Claustrum: Projective Identification in Couples

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Tamara Feldman
Keyword(s):  
Psychological Health ◽  
Projective Identification ◽  
The Self ◽  
The Other ◽  
Intimate Partners ◽  
And Control ◽  
The Relationship ◽  
As If

This paper is a contribution to the growing literature on the role of projective identification in understanding couples' dynamics. Projective identification as a defence is well suited to couples, as intimate partners provide an ideal location to deposit unwanted parts of the self. This paper illustrates how projective identification functions differently depending on the psychological health of the couple. It elucidates how healthier couples use projective identification more as a form of communication, whereas disturbed couples are inclined to employ it to invade and control the other, as captured by Meltzer's concept of "intrusive identification". These different uses of projective identification affect couples' capacities to provide what Bion called "containment". In disturbed couples, partners serve as what Meltzer termed "claustrums" whereby projections are not contained, but imprisoned or entombed in the other. Applying the concept of claustrum helps illuminate common feelings these couples express, such as feeling suffocated, stifled, trapped, held hostage, or feeling as if the relationship is killing them. Finally, this paper presents treatment challenges in working with more disturbed couples.

Thomas More's “rule” of pleasure before, after, and inUtopia

Moreana ◽  
2017 ◽  
Vol 54 (Number 207) (1) ◽  
pp. 36-56
Author(s):  
Gerard Wegemer
Keyword(s):  
Human Nature ◽  
The Other ◽  
Biblical Allusions ◽  
De Officiis

After establishing a context of More's lifelong engagement with the “calculus” of pleasure, this essay shows how the section devoted to the Utopians' pleasure philosophy is structured around five formulations of a “rule” to calculate “true and honest [honesta]” pleasure in ways that playfully imitate and echo the “rule” Cicero formulates several times in De officiis to discern one's duty when there seems to be a conflict between honestas et utilitas. When followed, the Utopian pleasure calculus shows the necessary role of societas, officii, iustitia, caritas, and the other aspects of human nature, most importantly friendship, that Cicero stresses in his rule and that he argued Epicurus ignored. Much of the irony and humor of this section depends on seeing the predominance of Ciceronian vocabulary in Raphael's unusual defense [patrocinium] of pleasure, rather than a Ciceronian defense of duty rooted in honestas. Throughout, however, this essay also shows how More goes beyond Cicero by including Augustinian and biblical allusions to suggest ways that our final end is not as Epicurus or the Stoics or Cicero claim; the language and allusions of this section point to a level of good cheer and care for neighbors and for God in ways quite different from any classical thinker.

BLOCKADE OF THE SURGE OF PROLACTIN AT PRO-OESTRUS BY ADMINISTRATION OF ANTI-OESTROGENIC SUBSTANCE, MER-25

1973 ◽  
Vol 74 (4) ◽  
pp. 769-774 ◽  
Author(s):  
Akira Yokoyama ◽  
Hiroshi Tomogane ◽  
Katuaki Ôta
Keyword(s):  
Strong Evidence ◽  
The Other ◽  
Other Hand

ABSTRACT A non-steroidal oestrogen antagonist, MER-25, was administered to cycling rats for elucidating the role of oestrogen in the surge of prolactin observed on the afternoon of pro-oestrus (POe). In animals injected with 20 mg of MER-25 intramuscularly on the afternoon (16.30 h) of the first day of dioestrus (D-1), the surge of prolactin was blocked while the level of prolactin on the afternoon of POe of these animals was significantly higher than that of the corresponding controls injected with oil. Ovulation was also blocked in these animals treated with the drug on the afternoon of D-l. On the other hand, treatment on the morning (10.30 h) of the 2nd day of dioestrus failed to prevent not only the surge of prolactin but also ovulation. These observations provide strong evidence for the view that oestrogen is responsible for the surge of prolactin on the afternoon of POe, and that the surge is accompanied by that of LH.

ROLE OF THE THYROID GLAND IN DEVELOPMENT AND MAINTENANCE OF RENAL HYPERTENSION IN RATS

1960 ◽  
Vol XXXIV (III) ◽  
pp. 411-429 ◽  
Author(s):  
Melvin J. Fregly ◽  
Kenneth M. Cook
Keyword(s):  
Blood Pressure ◽  
Rate Increase ◽  
Renal Hypertension ◽  
The Other ◽  
Elevated Blood Pressure ◽  
Unit Weight ◽  
Elevated Blood ◽  
Inhibition Of Growth ◽  
Testicular Size

ABSTRACT The anti-thyroid drugs, thiouracil, propylthiouracil, and methimazole, prevented both development of elevated blood pressure and cardiac hypertrophy usually accompanying kidney encapsulation with latex envelopes. These drugs also reduced elevated blood pressure of rats with hypertension of 13 to 40 weeks' duration prior to drug administration. Addition of desiccated thyroid powder to diet containing an anti-thyroid drug overcame the anti-hypertensive effect of the latter. Withdrawal of thyroid powder only was followed by return of blood pressure to previous low level within 3 weeks. The results suggest that the anti-hypertensive effect of these drugs is related directly to the hypothyroidism produced rather than to extrathyroidal effects of the drugs. Comparison of potencies of the 3 drugs in terms of anti-hypertensive effect, inhibition of growth rate, increase in testicular size, and increase in thyroid size suggests that propylthiouracil and methimazole are equally potent per unit weight of drug. Thiouracil has approximately half the potency of the other two.

PENGARUH KUALITAS PRODUK DAN RELIGIUSITAS TERHADAP KEPUTUSAN NASABAH PRODUK SIMPANAN PADA BSM CABANG PURWOKERTO

2017 ◽  
Vol 4 (1) ◽  
pp. 189-215
Author(s):  
Yoiz Shofwa Shafrani
Keyword(s):  
Regression Analysis ◽  
Product Quality ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Analytical Tool ◽  
The Other ◽  
Financial Assets ◽  
Islamic Bank

Perkembangan dunia perbankan syariah tidak lepas dari peran para nasabah yang memberikan kepercayaan terhadap pihak perbankan untuk penyimpanan asset keuangannya. Faktanya banyak kelompok nasabah yang memutuskan untuk menjadi nasabah di perbankan syariah karena faktor religiusitasnya. Faktor lain yang dapat ikut mempengaruhi keputusan nasabah adalah kualitas produk. Di mana kualitas produk merupakan karakteristik yang melekat dari suatu produk. Kemungkinan yang terjadi bahwa kebanyakan nasabah pada perbankan syariah juga masih merupakan nasabah perbankan konvensional.Tujuan yang ingin dicapai dalam penelitian ini adalah untuk mengetahui pengaruh kualitas produk dan tingkat religiusitas nasabah terhadap keputusan nasabah untuk menyimpan dananya atau tidak di BSM Cabang Purwokerto. Alat analisis yang digunakan adalah analisis regresi linier berganda, dengan jumlah sampel 100 nasabah. Diperoleh hasil Y = 5,046 + 0,101X1 + 0,218X2. Berdasarkan uji F yang sudah dilakukan maka dapat diketahui bahwa variabel kualitas produk dan religiusitas secara bersama – sama berpengaruh terhadap keputusan nasabah untuk menyimpan dananya di BSM Cabang Purwokerto. Berdasarkan uji t yang sudah dilakukan dapat diketahui bahwa secara partial baik variabel kualitas produk maupun variabel religiusitas berpengaruh terhadap keputusan nasabah untuk menyimpan dananya di BSM Cabang Purwokerto. The progress of the Islamic bank cannot be separated from the role of its customers who give trust to the bank to deposit their financial assets. It is a fact many groups of customers decide to be the customers of the Islamic bank because of their religiosity. The other influences factor of a customer’s decision is the quality of the product. The aim of this research was to determine the effect of product quality and level of customers’ religiosity towards customers’ decision whether to keep their funds in Syariah Mandiri Bank, Branch of Purwokerto, or not. The analytical tool used was multiple linear regression analysis, with a sample of 100 customers. The results indicate Y = 5,046 + 0,101X1 + 0,218X2. Based on F, it can be seen that both variables of product quality and religiosity simultanously affect the customers’ decision to keep theirfunds in BSM Branch of Purwokerto. Based on t test, it can be seen that independently, either variable of product quality or variables of religiosityinfluences the customers’ decision to keep their funds in BSM Branch of Purwokerto.

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