A new model for the investigation of atresia in rhesus monkeys is presented. This model is based upon the reliable induction of an atresia-like process in the dominant preovulatory follicle (DF) by estradiol-17β administered subcutaneously via Silastic capsules for 24 h. Data obtained from follicular contents aspirated from treated animals demonstrated alterations in the putative markers of atresia similar to those described in other models of atresia. Although follicle size and appearance and volume of follicular fluid (FF) were unaltered in treated animals, FF was much more viscous than that aspirated from follicles in untreated animals; this was apparently due to a greater quantity of intercellular matrix that was sensitive to digestion by hyaluronidase. In treated animals, FF concentrations of estrogen (E) and progesterone (P) were depressed 3- and 6.6-fold, respectively. Viability of granulosa cells (GC) from these animals was reduced by 40%, as was their ability to release basal amounts of E and P in vitro. Accumulation of P by GC from treated animals approximated unstimulated control levels when human follicle-stimulating hormone (hFSH) was included in the culture. Therefore, FSH may have a limited capability to “rescue” GC from atresia induced by estradiol. The percentage of cells that bound 125I-hFSH maximally, as measured by autoradiography following 72 h in culture, was not altered by treatment. Oocytes from animals treated with estradiol showed signs of degeneration at aspiration, and deteriorated further in culture. This model is unique in that atresia can be induced in the single DF of a primate species, and thus avoids the disadvantages inherent to studying atresia of heterogeneous follicles in polytocous species. These results validate the putative markers of atresia and the model itself We anticipate that this model will be a valuable tool for studying the process of atresia.
Psychopathic individuals are notorious for their grandiose sense of self-worth and disregard for the welfare of others. One potential psychological mechanism underlying these traits is the relative consideration of "self" versus "others". Here we used task-based functional magnetic resonance imaging (fMRI) to identify neural responses during personality trait judgments about oneself and a familiar other in a sample of adult male incarcerated offenders (n = 57). Neural activity was regressed on two clusters of psychopathic traits: Factor 1 (e.g., egocentricity and lack of empathy) and Factor 2 (e.g., impulsivity and irresponsibility). Contrary to our hypotheses, Factor 1 scores were not significantly related to neural activity during self- or other-judgments. However, Factor 2 traits were associated with diminished activation to self-judgments, in relation to other-judgments, in bilateral posterior cingulate cortex and right temporoparietal junction. These findings highlight cortical regions associated with a dimension of social-affective cognition that may underlie psychopathic individuals' impulsive traits.
This study was designed to provide a detailed description of preovulatory follicular development and the associated hormonal patterns in rhesus monkeys. Follicular morphology was observed by laparoscopy, performed sequentially, during 20 menstrual cycles in 13 rhesus monkeys. Serum concentrations of follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol-17β (E2) and progesterone were determined by radioimmunoassay. We conclude that: a) follicular growth occurs in a curvilinear fashion, increasing from an average of 1.7 mm to 9.4 mm during the 11 days preceding the LH peak; b) the follicle destined for ovulation can be grossly identified as early as 9 days before the preovulatory gonadotropin surge in some animals, but with increasing confidence on Day -5; c) only in the minority of cycles do waves of follicular development occur in the ovaries of rhesus monkeys and then only during the early follicular phase; d) serum concentrations of E2 are linearly related to follicle size (P<0.01); and e) a curvilinear relationship (P<0.002) exists between serum concentrations of FSH and the follicle diameter.
Reproductive performance is reportedly reduced in some rhesus monkeys during the summer months, even when environmental conditions are controlled. The mechanism(s) underlying this phenomenon remain unknown. We noted that the pattern of folliculogenesis appeared to be altered in rhesus monkeys that continued to exhibit ovulatory menstrual cycles during the "nonbreeding" season. This study was designed to investigate the effect of season on development of the dominant follicle (DF) and upon levels of serum gonadotropins and sex steroids in animals maintained in a controlled environment. Forty-four menstrual cycles were evaluated from October, 1982 to October, 1983. Animals were housed individually in controlled light (12L:12D) and temperature (22–25°C). A DF was identified by laparoscopy on Day 6 of the cycle in only 45% of cycles during the months of May through September, compared with 87.5% the remainder of the year. No effect of season was detected on either the length of the menstrual cycle or luteal phase, mean follicular diameter, or the percentage of ovulatory cycles. During the follicular phase, amounts of follicle-stimulating hormone (FSH) in peripheral sera were depressed, whereas those of luteinizing hormone (LH) were consistently elevated. Amounts of circulating estradiol were similar between groups. However, serum concentrations of progesterone were markedly reduced in the summer. Development of the DF appeared to be delayed in the early follicular phase during the summer months in those rhesus monkeys that had ovulatory menstrual cycles. This delay was accompanied by an alteration in the FSH to LH ratio. Although most cycles were ovulatory, altered follicular development resulted in deficient luteal function.
This experiment was designed to determine the effect of exogenous steroids on the preovulatory follicle and to evaluate subsequent ovarian and pituitary function as related to development of a substitute follicle. The original preovulatory follicle was identified by laparoscopy on Day 6 of the menstrual cycle in 29 monkeys, and Silastic capsules containing cholesterol, estradiol-17j3 (E2), or progesterone (P) were implanted s.c. in the following groups of animals: A) one cholesterol capsule for 48 h, B) six E2 capsules for 48 h, C) four E2 capsules for 48 h, D) four E2 capsules for 24 h, E) four E2 plus one P capsule for 48 h, and F) one P capsule for 48 h. Serum concentrations of follicle stimulating hormone (FSH), luteinizing hormone (LH), E2, and P were determined by radioimmunoassay. As expected, treatment with E2, for48 h resultedinprematuresurgesofLH and FSH, butno surges were induced with E2 treatmentfor24 h or withP treatments. Rather, small increases in FSH (but not LH) were consistently noted following removal of the latter implants. Regardless of the E2 or P treatment used or the response observed in gonadotropmn secretion, serum concentrations of endogenous E2 declined within 36 h after the capsules were implanted, and the preovulatory follicle regressed. In animals receiving cholesterol, hormone profiles were typical of those in normal menstrual cycles and ovulation occurred at the usual time. Following the FSH increases described above and atresia of the original preovulatory follicle, a different follicle developed and ovulated with normal luteal function ensuing. These extended follicular phases averaged 23.1 days, but the intervals from the FSH increase to ovulation approximated the length of a normal follicular phase (13.5 days in our control animals). These results indicate that elevated serum concentrations of E2 or P during development of the follicle otherwise destined to ovulate disrupt the preovulatory development and result in atresia; based on declining amounts of estrogen in the peripheral circulation, this effect may be exerted within the first day of treatment. Furthermore, the consistent association between FSH increases and renewed follicular development suggests, but does not prove, a cause and effect relationship between these events.
During much of the past century, it was widely believed that phonemes*the human speech sounds that constitute words*have no inherent semantic meaning, and that the relationship between a combination of phonemes (a word) and its referent is simply arbitrary. Although recent work has challenged this picture by revealing psychological associations between certain phonemes and particular semantic contents, the precise mechanisms underlying these associations have not been fully elucidated. Here we provide novel evidence that certain phonemes have an inherent, nonarbitrary emotional quality. Moreover, we show that the perceived emotional valence of certain phoneme combinations depends on a specific acoustic feature*namely, the dynamic shift within the phonemes’ first two frequency components. These data suggest a phoneme-relevant acoustic property influencing the communication of emotion in humans, and provide further evidence against previously held assumptions regarding the structure of human language. This finding has potential applications for a variety of social, educational, clinical, and marketing contexts.
Serum progestin and 17β-estradiol concentrations were measured during the breeding season of S. sciureus. Serum concentrations of both estradiol and progestins were markedly higher than those reported for other primate species. In the cycles examined the peak values of estradiol were 503.4 ± 57.5 pg/ml and 399.5 ± 27.7 ng/ml for progestins. Each steroid fluctuated in a cyclic pattern. Based upon these cyclic fluctuations the reproductive cycle of the squirrel monkey was estimated to be approximately 9 days in length.
