Male and female flowers of the dioecious plant sorrel show different patterns of MADS box gene expression

Male and female flowers of the dioecious plant sorrel (Rumex acetosa) each produce three whorls of developed floral organs: two similar whorls of three perianth segments and either six stamens (in the male) or a gynoecium consisting of a fertile carpel and two sterile carpels (in the female). In the developing male flower, there is no significant proliferation of cells in the center of the flower, in the position normally occupied by the carpels of a hermaphrodite plant. In the female flower, small stamen primordia are formed. To determine whether the organ differences are associated with differences in the expression of organ identity genes, cDNA clones representing the putative homologs of B and C function MADS box genes were isolated and used in an in situ hybridization analysis. The expression of RAD1 and RAD2 (two different DEFICIENS homologs) in males and females was confined to the stamen whorl; the lack of expression in the second, inner perianth whorl correlated with the sepaloid nature of the inner whorl of perianth segments. Expression of RAP1 (a PLENA homolog) occurred in the carpel and stamen whorls in very young flower primordia from both males and females. However, as soon as the inappropriate set of organs ceased to develop, RAP1 expression became undetectable in those organs. The absence of expression of RAP1 may be the cause of the arrest in organ development or may be a consequence.     

Sex determination in dioecious Silene latifolia. Effects of the Y chromosome and the parasitic smut fungus (Ustilago violacea) on gene expression during flower development

We have embarked on a molecular cloning approach to the investigation of sex determination in Silene latifolia Poiret, a dioecious plant species with morphologically distinguishable sex chromosomes. One of our key objectives was to define a range of genes that are up-regulated in male plants in response to Y chromosome sex-determination genes. Here we present the characterization of eight male-specific cDNA sequences and classify these according to their expression dynamics to provide a range of molecular markers for dioecious male flower development. Genetically female S. latifolia plants undergo a partial sex reversal in response to infection by the parasitic smut fungus Ustilago violacea. This phenomenon has been exploited in these studies; male-specific cDNAs have been further categorized as inducible or noninducible in female plants by smut fungus infection. Analysis of the organ-specific expression of male-specific probes in male and female flowers has also identified a gene that is regulated in a sex-specific manner in nonreproductive floral tissues common to both male and female plants. This observation provides, to our knowledge, the first molecular marker for dominant effect of the Y chromosome in nonreproductive floral organs.     

A floral third whorl-specific marker gene in the dioecious species white campion is differentially expressed in mutants defective in stamen development

The CCLS4 gene of white campion is specifically expressed in anther epidermis and endothecium from pre- to post-meiotic stages. We report on a detailed in situ analysis of the gene's expression and show that it is a marker of the floral third whorl. The gene is expressed (1) in the anther (epidermis, parietal cells and the derived endothecium) in normally developing stamens and (2) in distinct sub-domains of third-whorl epidermis in mutants exhibiting aberrant states of parietal differentiation. Our results suggest that CCLS4 may fulfil different functions during pre- and post-meiotic anther development and reveal the complex role parietal cells may play during early stamen formation.     

Spatial learning in male and female Long-Evans rats.

Male and female Long-Evans rats were tested in the Morris water maze at age 6 mo. A place training procedure, in which rats learned the position of a camouflaged platform, was followed by cue training, in which rats escaped to a visible platform. No sex difference was found in place learning ability. Search accuracy on probe trials, when the platform was unavailable, was also equivalent for the male and female groups. These results contrast with previous studies of rodents at younger ages, which have reported a male advantage in spatial learning. It is suggested that the age at which rats are assessed may be an important factor, possibly reflecting a different course in the relatively protracted maturation of the hippocampus in male and female rats. The results of this investigation are also discussed with reference to studies of sex differences for spatial abilities in humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Regulation of sulfotransferase mRNA expression in male and female rats of various ages

Sulfotransferases (SULTs) are Phase II drug-metabolizing enzymes that catalyze the addition of a sulfuryl moiety to both endogenous compounds, including steroids and neurotransmitters, and certain xenobiotics, including N-hydroxy-2-acetylaminoflourine and phenolic compounds, like alpha-naphthol. In contrast to certain Phase I drug-metabolizing enzymes, little is known about the regulation of the sulfotransferases. These series of studies were designed to analyze SULT mRNA expression and hormonal regulation in male and female rats. The hepatic expression of six different SULT isoforms was examined including three phenol SULTs and three hydroxysteroid SULTs. SULT mRNA expression was examined in adult and developing rats, as well as, in hypophysectomized (HX) and growth hormone-supplemented HX animals. SULT1A1 is thought to be important for the sulfation of simple phenols and its mRNA expression is about twice as high in adult male as in female rats. This difference in SULT1A1 mRNA levels is largely due to a greater decrease in mRNA levels after puberty in female than in male rats. Hypophysectomy resulted in a decrease in expression of SULT1A1 mRNA in both male and female rats. Replacement of growth hormone (GH) by either intermittent injection (male pattern) or infusion (female pattern) failed to restore SULT1A1 expression. Sulfotransferase SULT1C1 has been implicated in activation of N-hydroxyacetylaminoflourine. In contrast to SULT1A1, SULT1C1 mRNA expression is about 10-fold higher in adult males than in adult female rats. This male-dominant expression pattern emerges at 40-50 days of age and is due to an increase in SULT1C1 mRNA in males. Hypophysectomy abolished SULT1C1 expression in male rats. Interestingly, replacement of GH by injection (male pattern) restored SULT1C1 mRNA expression in males and enhanced SULT1C1 expression in female rats to levels observed in adult male rats. GH infusion (female pattern) did not affect SULT1C1 mRNA expression in either male or female rats. Estrogen sulfotransferase (SULT1E2) may play a role in estrogen homeostasis. Adult male rats express SULTIE2 mRNA at levels 10-fold higher than those observed in adult females and similar to SULT1C1, this is due to an increase in SULT1E2 mRNA occurring during puberty in the male rat. Hypophysectomy did not appreciably affect SULT1E2 expression in male rats, however in contrast to males, hypophysectomy markedly enhanced SULT1E2 expression in female rats. GH infusion suppressed SULT1E2 levels in HX male rats. The expression of hydroxysteroid sulfotransferases was also examined. The SULT-20/21 isoform was expressed in both male and female rats. Male expression of this isoform peaked at 30 days of age and then declined to approximately 30% of the level observed in adult females. SULT-20/21 mRNA expression increased sharply at 45 days of age in female rats and remained elevated. Expression of SULT-20/21 mRNA was decreased markedly by hypophysectomy in both male and female rats. GH injection did not affect SULT-20/21 mRNA expression in HX males, however this treatment resulted in a 4-fold increase in SULT-20/21 mRNA in HX females. GH infusion restored SULT-20/21 expression in HX-male rats. GH infusion did elevate SULT-20/21 mRNA expression in female-HX rats, but not to the level observed in intact females. Hydroxysteroid SULT isoform SULT-40/41 was expressed in adult female but not adult male rats. SULT-40/41 expression peaked at 15 days of age in both male and female rats and decreased thereafter. The decrease in expression was more pronounced in male rats. SULT-60 mRNA, like SULT-40/41, was expressed only in adult female rats. Male rats express SULT-60 at 30 days of age, but SULT-60 mRNA is undetectable at 60 days. SULT-60 mRNA was expressed in females only after day 30 and female SULT-60 mRNA expression remains high thereafter. SULT-40/41 and SULT-60 mRNA expression was increased by HX in male rats and decreased by HX in female rats. (ABSTRACT TRUNCATED)     

MK-801 and male odours induce c-fos expression in the AOB of juvenile female mice

The odours of adult males, which accelerate the timing of puberty of female mice, activate c-fos in the accessory olfactory bulb (AOB). To test the hypothesis that NMDA receptors are involved in the male odour-induced increase in c-fos expression, we studied the effects of the non-competitive NMDA receptor agonist MK-801 on male odour-induced c-fos expression in the AOB of juvenile female mice. Surprisingly, MK-801 increased FOS-like immunoreactivity (FLI) within the AOB in the absence of male odour and had no effect on male odour-induced c-fos expression. We suggest that MK-801 increases AOB mitral cell activity by disinhibiting GABAergic granule cells, resulting in increased c-fos expression throughout the AOB.     

Perinatal delta9-tetrahydrocannabinol exposure reduces proenkephalin gene expression in the caudate-putamen of adult female rats

Perinatal delta9-tetrahydrocannabinol (delta9-THC) exposure in rats affects several behavioral responses, such as opiate self-administration behavior or pain sensitivity, that can be directly related to changes in opioidergic neurotransmission. In addition, we have recently reported that the administration of naloxone to animals perinatally exposed to delta9-THC produced withdrawal responses, that resemble those observed in opiate-dependent rats. The purpose of the present study was to examine the basal opioid activity in the brain of adult male and female rats that had been perinatally exposed to delta9-THC. To this aim, proenkephalin mRNA levels were measured, by using in situ hybridization histochemistry, in the caudate-putamen, nucleus accumbens, central amygdala and prefrontal cingulate cortex. The results showed a marked reduction in proenkephalin mRNA levels in the caudate-putamen of delta9-THC-exposed females as compared to oil-exposed females, whereas no changes were observed between delta9-THC- and oil-exposed males. There were no differences in proenkephalin mRNA levels in the nucleus accumbens, central amygdala and prefrontal cingulate cortex between males and females perinatally exposed to delta9-THC and their respective controls, although a certain trend to decrease was observed in delta9-THC-exposed females. In summary, perinatal exposure to delta9-THC exposure decreased proenkephalin gene expression in the caudate-putamen of adult rats, although this effect exhibited a marked sexual dimorphism since it was only seen in females. This result is in agreement with a previous observation from our laboratory that females, but not males, that had been perinatally exposed to delta9-THC, self-administered more morphine in adulthood. This suggests that low levels of proenkephalin mRNA may be used as a predictor of greater vulnerability to opiates.     

Correction of total incontinence in male and female epispadias

Between 1946 and 1980, 54 patients with epispadias and total urinary incontinence were evaluated at our institution. Factors critical to the achievement of complete continence include deferral of surgery until at least 3 yr of age, the patient having a well-developed bladder with adequate capacity and musculature, and maturation of the prostate at puberty in males. Complete continence was obtained in 9 of 11 female patients (82%). Fourteen of 35 male patients obtained complete urinary continence in the initial postoperative period. Complete urinary control was delayed until puberty in 11 additional patients, for an overall success rate of 25 of 35 males (71%). The significant increase in continence with the onset of puberty in males demonstrates the importance of expectant management of the child's progress in relation to the potential contribution of prostatic maturation in the development of urinary control.     

Age-related decrease in the hypothalamic CRH mRNA expression is reduced by dehydroepiandrosterone (DHEA) treatment in male and female rats

The epidemiology of the association between migraine and epilepsy is reviewed. Migraine-related epilepsy is categorized using defined diagnostic criteria. Migraine-induced epilepsy is only one of several migraine-related epileptic syndromes.     

Role of maternal psychopathology in male and female schizophrenics.

Selecting from records of a child guidance clinic, the psychopathology of 165 mothers of male and female children and adolescents was studied in order to investigate sex differences in the degree of relationship between mother's mental status and the child's later hospitalization for schizophrenia. Of the children, 108 were later hospitalized for schizophrenia, while 57 achieved an adequate adjustment in areas of work and interpersonal relationships. For the girls, those who became schizophrenic had severely disturbed mothers significantly more often than did those who achieved an adequate adjustment (p     

Ratio of male and female characters in a dream series

The present study investigated the change in gender ratio of dream characters in relation to the dreamer's environment in waking-life and found a preponderance of male characters in the subject's dream while living in a 'male' environment which was not present while living in a 'female' environment. The results support the continuity hypothesis of dreaming and stress the importance of situational factors rather than personality factors in the explanation of the gender ratio of dream characters.     

Estrogen and the neural mediation of female–male mounting in the rat.

Sexually receptive females mount sexually sluggish males to entice them to copulate, and estrogen and male olfactory cues mediate this female–male mounting (FMM) in the rat. This study examined whether brain regions that concentrate steroid hormones and receive olfactory projections were important for the mediation of FMM. Fos induction was observed within the medial amygdala, medial preoptic area, and ventromedial hypothalamus of ovariectomized, hormone-primed rats that displayed FMM compared with rats that did not. Excitotoxic lesions of those regions eliminated FMM, whereas implants of crystalline estradiol benzoate to the ventromedial hypothalamus, but not the medial preoptic area or medial amygdala, restored FMM. These data indicate that the ventromedial hypothalamus is a critical area of convergence of hormonal, olfactory, and somatosensory inputs for FMM. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Typicality, familiarity and the recognition of male and female faces.

22 male and 43 female undergraduates provided judgments of typicality, familiarity, and recognition for each of 209 photographs of male and female faces. Results support the notion that the same-sex bias in recognition often found with female Ss is a function of perceived typicality: Female Ss rated female faces to be more typical than male faces, whereas male Ss showed no such bias. The same pattern of results was found for false–positive responses on a test of item recognition. The rated familiarity of the faces was not related to the Ss' recognition judgments, suggesting that the perceived context-free familiarity of faces is not the source of the effects of typicality or sex of face on the recognition of faces. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pharmacokinetic evaluation of liposomal encapsulated ampicillin in male and female rats

The dispositions of free and liposomal entrapped ampicillin were compared in male and female rats after i.v. administration. Serial blood samples were collected for 2 h in the free drug study and 12 h for the liposomal formulation. Pharmacokinetic parameters obtained with free drug were not significantly different between genders. However, gender significantly influenced the disposition of liposomal encapsulated ampicillin. While no difference was observed in distribution t1/2 between genders, female rats had a shorter MRT, smaller Vss and Vt, and faster clearance as compared to male rats. In a second study, spleen, liver, kidney, heart, and lung were harvested post-injection of free and liposomal entrapped ampicillin. Free ampicillin did not distribute extensively into the tissue compartment and no gender difference was noted. In contrast, liposomal encapsulation resulted in a substantial tissue uptake. In general, female rats had higher concentrations in the spleen and lung as compared to male rats. In vitro plasma stability was not significantly different, suggesting that destabilization of the liposomes does not play a large role in the dispositional differences observed in these studies. However, in vivo interaction of liposomes and plasma lipoproteins may influence the disposition of encapsulated drug.     

Personality profiles of male and female positive role models in medicine

This study was designed to investigate the personality profile of positive role models in medicine. Participants were a national sample of 188 physicians (164 men, 24 women) who had been nominated by the chief executive officers of their institutions as positive role models and who completed the Revised NEO Personality Inventory. Compared to the general population, these 188 male and female positive role models in medicine scored higher on Conscientious factor, and on Achievement Striving, Activity, Competence, Dutifulness, Trust, Assertiveness, and Altruism facets, but they scored lower on the Vulnerability facet than the general population. In addition, the male role models scored significantly higher than men in the general population on the Agreeableness factor, and the female role models obtained significantly higher scores than the population norms on Extraversion and Openness factors, and on Feelings, Ideas, Positive Emotions, Values, Warmth, Aesthetics, and Fantasy facets. The female role models scored far below their sex-related norms on Neuroticism factor and on Angry Hostility facet. Comparisons between the male and female role models showed that the female role models scored higher on the Openness factor, and on the Feelings, Positive Emotions, Aesthetics, and Fantasy facets of personality. Implications in medical education and in explaining, assessing, and improving the qualities that contribute to professional success and in promoting the concept of "positive medicine" are discussed.     

A genetic study of dentin growth in the mandibular second and third molars of male mice

Although the influence of genetic and environmental factors on the completed crown size of mandibular molars in mice is well known, such influence on the growth process of the mandibular second and third molars of mice has not yet been clarified. The purpose of the present study is to examine the growth pattern of the dentinal formation and evaluate the relative contributions of both genetic and environmental factors to longitudinal dentin formation by the use of the partial diallel cross-genetic approach, the time-marking method and a computerized image measurement system. The following results were obtained: 1) the onset of dentinal formation in the second molar was on the 6-9th day after birth, while that of the third molar was on the 9-12th day after birth; 2) the best fitted growth curve of the dentinal formation for the first molar was the fifth order polynomial equation, while for the second molar the fourth order polynomial equation was best, and for the third molar the third order polynomial equation was best; 3) maternal effect strongly influenced the second and the third molar dentin growth at an early stage of postnatal growth. Thus, it could be concluded that the dentinal formation growth pattern differed among the three kinds of mouse molars while maternal environmental factors, in addition to genetic factors, played an important role in the mouse second and third molar dentin growth during the early stage of postnatal growth.     

Organization of needs in male and female drug and alcohol users.

Administered the Personality Research Form (PRF) to 1,095 college students divided into groups of nonusers of drugs and alcohol, users of alcohol only, users of marihuana, and users of a variety of drugs in addition to marihuana. The PRF was factored for each of the groups, with 6 factors extracted in each analysis. Subgroup factor-pattern matrices were aligned to a common position, and the stability of the factorial solution across groups was assessed. All the factors were stable. The total sample was also divided into 4 groups based on the year of testing and the sex of the student. A 6-factor solution was calculated for each group, and factor stability across analyses was examined. The factor pattern matrices for male and female samples were quite similar. Moreover, the pattern of correlations among the primary factors found in each analysis was stable across subgroups. Results suggest that the organization of motivational tendencies in college students is the same for both sexes and for different types of substance users. The relationship of the factors to several other personality research variables is discussed. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prolactin-releasing effect of buspirone in developing and adult male and female rats

The prolactin-releasing effects of buspirone, an azaspirodecanedione anxiolytic drug unrelated to the benzodiazepines in structure and pharmacologic properties, was examined in developing and adult male and female rats. The possibility that effects of this drug on hormone release could be modulated by neonatal brain sexual differentiation was also evaluated. A single injection of buspirone, 2 or 10 mg/kg body wt, increased serum prolactin (PRL) levels in both sexes; the increase was significant from Day 12 onward. The PRL-releasing effect increased with age. No significant sexual differences were observed in younger rats, but in peripubertal and adult animals, the hyperprolactinemic response was higher in the female. Neonatal androgenization of females or orchidectomy of males failed to modify the PRL-releasing action of buspirone. Serum titers of luteinizing hormone and follicle-stimulating hormone were not modified by buspirone at any age. The present results show for the first time the ontogeny of the PRL-releasing effect of buspirone in male and female rats, and provide evidence that the response is higher in the female and that the effect does not depend on brain sexual differentiation.     

Perceiving the causes of success and failure of male and female performers.

Studied sex differences in attributions of ability, effort, task difficulty, or luck given by 320 Ss at 4 grade levels (5th, 8th, and 11th grades and college) to the outcomes of 4 masculine tasks performed by either male or female actors. Results suggest that differential perceptions of male and female performances appear to be well established in both boys and girls by the 5th grade. (PsycINFO Database Record (c) 2010 APA, all rights reserved)