scholarly journals The production of excretory-secretory molecules from Heligmosomoides polygyrus bakeri fourth stage larvae varies between mixed and single sex cultures

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Marta Maruszewska-Cheruiyot ◽  
Ludmiła Szewczak ◽  
Katarzyna Krawczak-Wójcik ◽  
Magdalena Głaczyńska ◽  
Katarzyna Donskow-Łysoniewska
Keyword(s):  
Sex Pheromones ◽  
Pheromone Communication ◽  
Larval Culture ◽  
Heligmosomoides Polygyrus ◽  
Single Sex ◽  
Opposite Sex ◽  
Potential Vaccine ◽  
Immunomodulatory Properties ◽  
Therapeutic Compounds ◽  
Immunomodulatory Potential

Abstract Background Excretory-secretory (ES) products are crucial in maintaining helminths in the host. Consequently, the proteins of ES are potential vaccine molecules and potential therapeutic agents for autoimmune diseases. Heligmosomoides polygyrus bakeri, a gastrointestinal parasite of mice, is a model of hookworm infection in humans. ES produced by both sexes of H. polygyrus bakeri L4 stage cultured separately shows different immunomodulatory properties than ES obtained when both sexes are cultured together. Accordingly, the objective of this study was to identify and compare the excretory-secretory molecules from single-sex and mixed cultures. Methods The composition of ES of male and female L4 stage nematodes in the presence (cultured together) or absence (cultured alone) of the opposite sex was examined. Proteins were identified using mass spectrometry. The functions of identified proteins were explored with Blast2GO. Results A total of 258 proteins derived from mixed larval culture in the presence of sex pheromones were identified, 160 proteins from pure female cultures and 172 from pure male cultures. Exposure of nematodes to the sex pheromones results in abundant production of proteins with immunomodulatory properties such as Val proteins, acetylcholinesterases, TGF-β mimic 9 and HpARI. Proteins found only in ES from mixed larval cultures were TGF-β mimics 6 and 7 as well as galectin. Conclusions The presence of the opposite sex strongly influences the composition of ES products, probably by chemical (pheromone) communication between individuals. However, examination of the composition of ES from various conditions gives an opportunity for searching for new potentially therapeutic compounds and anthelminthics as well as components of vaccines. Manipulation of the nematode environment might be important for the studies on the immunomodulatory potential of nematodes.

Coeducation and Sex Roles

1986 ◽  
Vol 30 (2) ◽  
pp. 117-131 ◽  
Author(s):  
Mary B. Harris
Keyword(s):  
High School ◽  
University Students ◽  
Sexual Intercourse ◽  
Sex Roles ◽  
Natural Attitude ◽  
Single Sex ◽  
Happy Marriage ◽  
Opposite Sex ◽  
Males And Females ◽  
Coeducational High Schools

In order to test conflicting hypotheses about the effects of coeducational versus single-sex schooling, 538 first-term Australian university students who had attended single sex or coeducational high schools were compared on a number of variables relating to sex roles. Those from the two types of schools did not differ significantly on the Australian Sex Roles Inventory or on a measure of nontraditional attitudes towards sex roles, although males and females differed in predictable ways. Most subjects, particularly those from coeducational schools, felt that coeducational schools are preferable and lead to a more natural attitude towards the opposite sex. Subjects from coeducational rather than single-sex schools said that they had more opposite-sex friends in high school and were more likely to feel that their school helped rather than hindered their everyday relations with the opposite sex and their chances for a happy marriage. However subjects did not feel that boys and girls learn or behave better in coeducational schools, and there were no differences in the percentages of subjects from the two types of schools who reported having had sexual intercourse or been in love while in high school. The single-sex schools attended tended to differ from the coeducational ones in being smaller, more urban, and more likely to be selective, which made comparisons difficult to interpret. Nevertheless it seems reasonable to conclude that coeducational schooling, at least for this selective sample, may have some advantages in fostering interactions with the opposite sex.

scholarly journals Putative sex-specific human pheromones do not affect gender perception, attractiveness ratings or unfaithfulness judgements of opposite sex faces

2017 ◽  
Vol 4 (3) ◽  
pp. 160831 ◽  
Author(s):  
Robin M. Hare ◽  
Sophie Schlatter ◽  
Gillian Rhodes ◽  
Leigh W. Simmons
Keyword(s):  
Sex Pheromones ◽  
Experimental Studies ◽  
Female Gender ◽  
Double Blind ◽  
Male And Female ◽  
Gender Perception ◽  
Opposite Sex ◽  
Computer Based ◽  
Human Pheromones ◽  
Human Participants

Debate continues over the existence of human sex pheromones. Two substances, androstadienone (AND) and estratetraenol (EST), were recently reported to signal male and female gender, respectively, potentially qualifying them as human sex pheromones. If AND and EST truly signal gender, then they should affect reproductively relevant behaviours such as mate perception. To test this hypothesis, heterosexual, Caucasian human participants completed two computer-based tasks twice, on two consecutive days, exposed to a control scent on one day and a putative pheromone (AND or EST) on the other. In the first task, 46 participants (24 male, 22 female) indicated the gender (male or female) of five gender-neutral facial morphs. Exposure to AND or EST had no effect on gender perception. In the second task, 94 participants (43 male, 51 female) rated photographs of opposite-sex faces for attractiveness and probable sexual unfaithfulness. Exposure to the putative pheromones had no effect on either attractiveness or unfaithfulness ratings. These results are consistent with those of other experimental studies and reviews that suggest AND and EST are unlikely to be human pheromones. The double-blind nature of the current study lends increased support to this conclusion. If human sex pheromones affect our judgements of gender, attractiveness or unfaithfulness from faces, they are unlikely to be AND or EST.

scholarly journals Maternal Serum Steroid Levels Are Unrelated to Fetal Sex: A Study in Twin Pregnancies

2005 ◽  
Vol 8 (2) ◽  
pp. 173-177 ◽  
Author(s):  
Celina C. C. Cohen-Bendahan ◽  
Stephanie H. M. van Goozen ◽  
Jan K. Buitelaar ◽  
Peggy T. Cohen-Kettenis
Keyword(s):  
Prenatal Exposure ◽  
Twin Pair ◽  
Maternal Serum ◽  
The Other ◽  
Male Fetus ◽  
Female Fetus ◽  
Single Sex ◽  
Opposite Sex ◽  
The Relationship ◽  
Twin Pregnancies

AbstractIncreased prenatal exposure to testosterone (T) in females of an opposite-sex (OS) twin pair may have an effect on the development of sex-typical cognitive and behavioral patterns. The prenatal exposure to T due to hormone transfer in OS twin females may occur in two ways, one directly via the feto–fetal transfer route within the uterus, the other indirectly through maternal–fetal transfer and based in the maternal–fetal compartment. Although some studies in singletons indeed found that women pregnant with a male fetus have higher T levels during gestation than women pregnant with a female fetus, many other studies could not find any relation between the sex of the fetus and maternal serum steroid levels. Therefore at present it is unclear whether a pregnant woman bearing a male has higher levels of T than a woman bearing a female. Up to this point, no-one has investigated this issue in twin pregnancies. We examined the relationship between maternal serum steroid levels and sex of fetus in 17 female–female, 9 male–male and 29 OS twin pregnancies. No differences were observed between the maternal serum steroid levels of women expecting single-sex and mixed-sex offspring. It is concluded that the source of prenatal T exposure in females probably comes from the fetal unit, which is the direct route of fetal hormone transfer.

Attention to Sex in Psychological Research as Related to Journal Policy and Author Sex

1979 ◽  
Vol 4 (2) ◽  
pp. 175-184 ◽  
Author(s):  
Claire Etaugh ◽  
Deborah Bohn Spandikow
Keyword(s):  
Sex Differences ◽  
Child Development ◽  
Developmental Psychology ◽  
Editorial Policy ◽  
Psychological Research ◽  
Senior Author ◽  
Chi Square ◽  
Female Authors ◽  
Single Sex ◽  
Opposite Sex

From 1969 to 1974, Developmental Psychology, but not Child Development, specified that authors analyze for sex differences. The authors examined 503 studies published in Child Development and Developmental Psychology in 1971 and 1975. Sex of senior author, subjects and experimenter(s) were recorded for each study. If subjects of both sexes were used, the presence or absence of the following were noted: (a) analysis of sex differences; (b) hypotheses regarding sex differences; (c) mention of subjects' sex in the abstract. For single-sex-subject studies, mention of subjects' sex in the discussion or conclusion was noted. Using these data as dependent variables, chi-square analyses were performed comparing: (a) the two journals; (b) 1971 and 1975 authors; and (c) male and female authors. The findings were: (a) More attention was paid to sex in Developmental Psychology when the journal had a written editorial policy regarding this factor; (b) Evidence was mixed for increasing awareness of sex as a variable between 1971 and 1975; (c) Female authors were more aware of sex than were male authors in 1971 but not in 1975; (d) In both years, authors used own-sex subjects and experimenters more than those of the opposite sex; (e) Developmental psychologists, as compared to psychologists in other areas previously examined, were more sensitive to sex as a variable.

Moth pheromone genetics and evolution

1993 ◽  
Vol 340 (1292) ◽  
pp. 167-177 ◽  
Keyword(s):  
Sexual Selection ◽  
Mate Choice ◽  
Sex Pheromones ◽  
Species Recognition ◽  
Empirical Support ◽  
Mate Recognition ◽  
Genetic Dissection ◽  
Pheromone Communication ◽  
Mate Finding ◽  
Important Progress

Sex pheromone communication in moths is a well investigated case of mate-finding by chemical signals, but the evolutionary causes of the great complexity and diversity of these signals are still not generally agreed on. In the present paper, I argue that there is no reason to dismiss species recognition as a possible cause of evolutionary change in moth sex pheromones. Admittedly, selection for species recognition cannot explain all of the diversity in sex pheromones and the data supporting this contention are weak, but the alternative causes suggested, invoking mate choice between conspecifics as the mechanism of sexual selection, has so far no empirical support. Finding and analysing genes responsible for m ate choice is important to corroborate any theory of sexual selection and speciation. In this respect genetic dissection of moth pheromone communication has provided important progress. Mendelian genes controlling differences in m ate choice and in the production of mate recognition signals have been found. Polymorphic pheromone systems give the population biologists unique possibilities to study mate choice and selection at the genotype level in nature.

scholarly journals On the origins of sexual dimorphism in butterflies

2010 ◽  
Vol 278 (1714) ◽  
pp. 1981-1988 ◽  
Author(s):  
Jeffrey C. Oliver ◽  
Antónia Monteiro
Keyword(s):  
Sexual Dimorphism ◽  
The Novel ◽  
Temporal Separation ◽  
Intralocus Sexual Conflict ◽  
Single Sex ◽  
Wing Patterns ◽  
Sexual Selection Theory ◽  
Opposite Sex ◽  
Phylogenetic Framework ◽  
Alternative Processes

The processes governing the evolution of sexual dimorphism provided a foundation for sexual selection theory. Two alternative processes, originally proposed by Darwin and Wallace, differ primarily in the timing of events creating the dimorphism. In the process advocated by Darwin, a novel ornament arises in a single sex, with no temporal separation in the origin and sex-limitation of the novel trait. By contrast, Wallace proposed a process where novel ornaments appear simultaneously in both sexes, but are then converted into sex-limited expression by natural selection acting against showy coloration in one sex. Here, we investigate these alternative modes of sexual dimorphism evolution in a phylogenetic framework and demonstrate that both processes contribute to dimorphic wing patterns in the butterfly genera Bicyclus and Junonia . In some lineages, eyespots and bands arise in a single sex, whereas in other lineages they appear in both sexes but are then lost in one of the sexes. In addition, lineages displaying sexual dimorphism were more likely to become sexually monomorphic than they were to remain dimorphic. This derived monomorphism was either owing to a loss of the ornament (‘drab monomorphism’) or owing to a gain of the same ornament by the opposite sex (‘mutual ornamentation’). Our results demonstrate the necessity of a plurality in theories explaining the evolution of sexual dimorphism within and across taxa. The origins and evolutionary fate of sexual dimorphism are probably influenced by underlying genetic architecture responsible for sex-limited expression and the degree of intralocus sexual conflict. Future comparative and developmental work on sexual dimorphism within and among taxa will provide a better understanding of the biases and constraints governing the evolution of animal sexual dimorphism.

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