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Dive into the research topics where Richard M. Harrison is active.

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Featured researches published by Richard M. Harrison.


Primates | 1977

Correlation of perineal swelling with serum ovarian hormone levels, vaginal cytology, and ovarian follicular development during the baboon reproductive cycle

D. E. Wildt; L. L. Doyle; S. C. Stone; Richard M. Harrison

Perineal swelling was correlated with changes in vaginal cytology and serum ovarian hormone levels and with development of the ovarian follicle. The average length of 66 menstrual cycles as seen in 12 mature baboons was 35.7±.66 days with a range of 25 to 47 days. Laparoscopic observations and photographic documentation of follicular development were made as early as 13 days prior to ovulation with the most rapid follicular maturation occurring 24 to 48 hours before ovulation. In 38.5% of the cycles ovulation occurred on the last day of maximal perineal tumescence with 26.9% of the ovulations occurring one day after initial detumescence. In 17.8% ovulations occurred two to five days prior to detumescence while the remaining 17.8% occurred two to three days following first observed detumescence. The mean progesterone level during the follicular phase was significantly less than that in the luteal phase, 1.6 and 6.7 ng/ml respectively (p<0.01). The level of estrogen detected during the periods of maximal tumescence was significantly higher (p<0.05) than that detected in the remainder of the cycle, 19.8 and 5.9 pg/ml respectively. Vaginal smears were stained, observed microscopically, and found to correlate with perineal swelling, hormone levels, and laparoscopic observations.


Fertility and Sterility | 1986

Pathophysiology of varicocele in nonhuman primates: Long-term seminal and testicular changes

Richard M. Harrison; Ronald W. Lewis; James A. Roberts

Varicocele was surgically induced in monkeys to study the long-term effects of the condition on seminal and testicular parameters. Sperm motility was depressed but improved after varicocelectomy. Sperm concentration was less affected, but sperm morphology showed long-term degenerative changes, i.e., for more than 2 years. Testicular blood flow was depressed acutely but returned to normal after 2 years. Electron microscopy showed changes in the basal lamina and spermatogonia that persisted throughout the study. Left adrenalectomy, at the time of varicocele induction, did not alter the development of varicocele-related changes. The sequence of changes suggests that the effects of this experimental varicocele may be reversed in the monkey model through changes in collateral and ancillary revascularization.


Journal of Medical Primatology | 2007

Male‐to‐male differences in post‐thaw motility of rhesus spermatozoa after cryopreservation of replicate ejaculates

S.P. Leibo; H. Michael Kubisch; R. Dee Schramm; Richard M. Harrison; Catherine A. VandeVoort

Background  The efficiency of controlled propagation to produce rhesus monkeys of particular genotypes can be maximized by use of cryopreserved spermatozoa collected from specific males to inseminate appropriate females. But this assumes that semen from males with different genotypes can be cryopreserved with equal effectiveness.


American Journal of Primatology | 1996

Behavioral, immunological, and hormonal responses associated with social change in rhesus monkeys (Macaca mulatta)

Margaret R. Clarke; Richard M. Harrison; Elizabeth S. Didier

Twelve animals to be socially reorganized in a group of 49 animals were compared with ten animals in a socially stable group (n = 51) for reproductive hormones, cortisol concentrations, immune function, and behavioral patterns for a 6 week baseline and 16 week postreorganization period. Cortisol values, mitogen‐induced lymphocyte blastogenesis, and rates of behavior reflected social events. Increased cortisols, increased noncontact aggression, and decreased mitogen response were associated with animal introductions. Increased cortisol concentration and decreased mitogen response correlated significantly only in animals removed from the group for trauma, and females successful at group membership exhibited lower cortisol concentrations. High‐ranking animals in small stable groups exhibited significantly higher lymphocyte proliferation than middle‐ or low‐ranking animals. While relative ranks established in small groups were maintained following reorganization, baseline cortisol values, immune measures, or male testosterone values did not predict success at group membership.


The Journal of Urology | 1979

Contact Scrotal Thermography: Application to Problems Of Infertility

Ronald W. Lewis; Richard M. Harrison

Traditionally, studies on the relationship between scrotal or testicular temperature and infertility have concerned patients with varicoceles. However, some varicoceles are difficult to palpate and, in fact, there now appears to be an entity called subclinical varicocele. These data have led to the development of a new diagnostic tool, a contact thermography camera, which is inexpensive in comparison to infrared thermography units, is portable and provides consistent permanent recordings of scrotal temperature. The initial use of this camera in 30 patients seen in an infertility clinic is reported.


Reproduction | 2007

Age as a determinant of reproductive success among captive female rhesus macaques (Macaca mulatta).

Christine Gagliardi; John R Liukkonen; Kathrine Phillippi-Falkenstein; Richard M. Harrison; H. Michael Kubisch

A retrospective analysis was performed on fertility outcomes among a colony of captive Indian rhesus monkeys. The analysis covered over 30 years and was based on 1443 females with a total of 11,453 pregnancies. Various determinants of fertility were assessed including birth rates, pregnancy loss, infant survival, interbirth intervals, and interval from last birth to death. Binary variables were analyzed with generalized linear models with random intercepts, while linear mixed models were used for analysis of continuous variables. Age of the dam was a significant factor in determining whether a pregnancy resulted in a birth and whether an infant survived the first 30 days with primiparous or older mothers being less likely to produce an infant surviving to that age. In contrast, sex proved to be the only significant factor in determining whether an infant lived to 1 year, with females being more likely to survive. The interval between births proved to be affected primarily by dam age, while the late death of an infant depressed the likelihood of an extended time interval between her last birth and her death. Overall, these results demonstrate that maternal age contributes significantly to a decline in fertility and older females can live relatively long periods following birth of their last infant.


Fertility and Sterility | 1981

Culture of seminal fluid in a fertility clinic.

Ronald W. Lewis; Richard M. Harrison; Gerald J. Domingue

To determine whether the culture of seminal fluid in a fertility clinic is of importance, bacterial cultures were obtained in a consecutive series of 96 patients. Routine bacteriologic cultures were performed within 1 hour of collection. Ureaplasma urealyticum (T-mycoplasma) cultures were also obtained in the last 31 of the patients in this series. Of these 96 patients, 11% showed significant bacterial growth (greater than 10(4) colonies/ml) in the semen specimens, 8% in those patients with normal semen analyses and 14% in those with abnormal analyses. Fifty-eight per cent of semen specimens were positive for U. urealyticum. In reference to normal and abnormal semen analyses the distribution was the same regardless of the presence or absence of U. urealyticum. Antibiotic treatment resulted in minor changes in motility and morphology in a few patients despite conversion to a negative culture. Cultures were also coordinated with microscopic urinalysis and the presence of white blood cells or bacteria in stained smears of semen. There were no significant differences between groups with positive or negative cultures. Trichomonas vaginalis was not seen.


Journal of Medical Primatology | 1980

Semen parameters in Macaca mulatta: ejaculates from random and selected monkeys.

Richard M. Harrison

Semen samples were collected by rectal probe electroejaculation techniques from groups of adult male rhesus monkeys. Mean values for 249 ejaculates from 100 monkeys were a sperm concentration of 419.43 x 10(6)/cm3 with 53.9% of the sperm showing progressive movement. Sperm concentration showed a positive rank correlation coefficient with sperm motility. Significant motility and concentration differences were found among groups. Seasonal differences were noted but were not significant. The study provides data that will aid investigators who are screening animals for studies involving reproductive potential.


Journal of Medical Primatology | 1996

GENOTYPIC ANALYSIS OF INFANT MACAQUES INFECTED TRANSPLACENTALLY AND ORALLY

Angela M. Amedee; Nedra Lacour; Louis N. Martin; Janice E. Clements; Rudolf B. Bohm; Billie B. Davison; Richard M. Harrison; Michael Murphey-Corb

Abstract: The SIV‐infected macaque provides an excellent model to study factors involved in maternal‐fetal transmission of HIV. In our prenatal transmission studies, female macaques were inoculated intravenously during midgestation with either SIV/DeltaB670 or a combination of SIV/DeltaB670 and the macrophage‐tropic molecular clone SIV/17E‐Fr. The females harbored a genetically diverse virus population at parturition, whereas a single genotype from the maternal quasispecies was identified in the infants. One of two variants was transplacentally transmitted to the infants, SIV/17E‐Fr or B670‐Cl 12, a genotype contained within the SIV/DeltaB670 inoculum. Both of these variants have been identified in the central nervous system of macaques that have developed encephalitis and they replicate in vitro on primary rhesus macrophages. These results suggest a critical role for macrophages in fetal infection in utero. In our perinatal transmission studies we have evaluated the viral genotypes found in two newborn macaques infected orally with SIV/DeltaB670 and in one infant infected via amniotic inoculation in late gestation. More than one viral genotype was identified in each infant, moreover, each infant harbored different genotypes. These results suggest different mechanisms are responsible for viral infection via these routes.


Experimental Biology and Medicine | 1999

Effect of Genistein on Steroid Hormone Production in the Pregnant Rhesus Monkey

Richard M. Harrison; Patricia P. Phillippi; Kenneth F. Swan; Michael C. Henson

Genistein is a phytoestrogen found in soy beans. Phytoestrogens have been reported to cause reproductive problems in sheep and rats. This research was conducted to determine the effects of genistein fed to rhesus monkeys during pregnancy, with specific interest on fetal growth and steroidogenesis in the maternal-fetoplacental unit. Two groups of five monkeys each were selected in early stages of pregnancy. One group was administered genistein in a fruit treat each weekday until Cesarean section 10 days prior to term. The second, control group, received fruit treats without genistein. Maternal blood samples were collected on Tuesday and Friday of each week. At delivery, samples were collected from the maternal peripheral circulation, uterine veins, uterine-ovarian veins, and the fetal heart. Comparisons between control and genistein-treated monkeys revealed no differences in the maternal weight gained during pregnancy, or in fetal weights or placental weights at delivery. Serum was assayed by radioimmunoassay (RIA) for estradiol, progesterone, dehydroepiandrosterone sulfate (DHEA-S), and estrone. No significant differences (P > 0.05) were noted in progesterone or DHEA-S levels at delivery or during the pregnancy; however, estradiol levels were higher (P < 0.05) in the four areas studied at delivery and in the maternal blood with advancing gestation. Additionally, estrone levels tended to increase more rapidly (P = 0. 057) in the maternal blood of monkeys receiving genistein than in untreated controls, suggesting that genistein may stimulate the deconjugation of estrone in the gut, thus allowing its reabsorption into the peripheral circulation and conversion to estradiol.

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Ronald W. Lewis

Georgia Regents University

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