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Dive into the research topics where Daniel H. Riddick is active.

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Featured researches published by Daniel H. Riddick.


American Journal of Obstetrics and Gynecology | 1977

Decidua: A possible source of amniotic fluid prolactin

Daniel H. Riddick; William F. Kusmik

The source of amniotic fluid prolactin was investigated with the use of amnion, chorion, placenta, and decidual tissue taken from term human pregnancy. Decidua alone of these tissues contained significant quantities of prolactin. The release of decidual prolactin was affected by the presence or absence of oxygen and protein, and the amount of prolactin released far exceeded the decrease in tissue content during incubation. It is concluded that: (1) decidua may be a major source of amniotic fluid prolactin, (2) synthesis of prolactin occurs during incubation of decidua, and (3) sufficient prolactin is present in the decidua to account for that found in amniotic fluid at term.


Life Sciences | 1978

Denovo synthesis of prolactin by human decidua

Daniel H. Riddick; Anthony A. Luciano; William F. Kusmik; Ila A. Maslar

Abstract Relatively large amounts of immunoreactive prolactin were measured in homogenates of human decidual tissue obtained immediately after delivery of normal term pregnancies. In order to study the release and possible synthesis of prolactin by this tissue, explants of decidua were incubated for 24 hours at 37°C in oxygenated Geys buffer containing 20% fetal calf serum. When cycloheximide was added to the medium in concentrations sufficient to prevent in vitro protein synthesis, 85–90% of the prolactin present in the tissue was released into the medium during the first 3 hours of incubation. No additional prolactin accumulated in either the medium or the tissue during the remainder of the incubation period. In the absence of cycloheximide, the prolactin concentration in the medium increased progressively during incubation, so that after 24 hours the total amount of hormone present in the tissue and medium was significantly greater than that in the tissue and medium prior to incubation (37.6 ± 9.6 ng/ml at 0 time vs 82.2 ± 7.7 ng/ml at 24 hours). When 3H-1-leucine (100 u Ci) was supplied during incubation, radioactive proteins were detected in the medium at 24 hr, 14–20% of which were specifically precipitated by antiserum to human pituitary prolactin. When aliquots of this medium were chromatographed on Sephadex G-100, 80–95% of the 3H-proteins precipitated by antiserum to pituitary prolactin eluted in the same position as did purified, iodinated pituitary prolactin. These data indicate that a species of prolactin which is identical to pituitary prolactin by the criteria of immunoprecipitation and gel chromatography is synthesized by human decidual tissue in vitro .


American Journal of Obstetrics and Gynecology | 1983

Prolactin production during in vitro decidualization of proliferative endometrium

Douglas C. Daly; Ila A. Maslar; Daniel H. Riddick

Decidua obtained in the late luteal phase of the human menstrual cycle has been shown to produce immunoreactive prolactin (PRL). The amount of PRL produced is a function of the extent of decidual differentiation. Further, the maintenance of decidualization and PRL production in specimens of late luteal phase in explant culture is dependent on the presence of progesterone (P). To further examine Ps effect on decidualization, PRL production was monitored during P-induced decidualization of proliferative endometrium in vitro. Samples of proliferative endometrium obtained from six hysterectomy specimens were cultured in Dulbeccos modified Eagle medium in the presence of no hormones, 200 pg/ml estradiol (E2) 20 ng/ml P, and 20 ng/ml P with 200 pg/ml E2. It was found that P alone or with E2 caused PRL production and histologic decidualization. However, E2 slowed the histologic progression of P-induced decidualization on days 2 and 4 and decreased the rate of PRL production (p less than 0.01) on days 6, 8, and 10 of culture. These data indicate that P alone is capable of inducing decidualization and initiating PRL production. Further, E2 can modify the rate and/or extent of this P-mediated phenomenon.


Fertility and Sterility | 1984

A randomized study of dexamethasone in ovulation induction with clomiphene citrate

Douglas C. Daly; Clifford A. Walters; Carlos E. Soto-Albors; Narendra Tohan; Daniel H. Riddick

Improved understanding of follicular dynamics has led to a reevaluation of suppression of adrenal androgens in ovulation induction. To test whether adrenal suppression during clomiphene citrate (CC) therapy would improve ovulation/pregnancy rates, 64 anovulatory patients who had not previously received CC were randomly assigned to receive either 50 mg CC on days 5 to 9 alone or with 0.5 mg dexamethasone (CC + DEX). Patients were then screened for dehydroepiandrosterone sulfate (DHEA-S) (normal range, 80 to 320 micrograms/dl), prolactin, testosterone, and semen analysis of the partner. Nine patients discontinued participation prior to completing the first treatment cycle, and ten patients were found to have either elevated prolactin (4), severe male factors (3), or tubal disease (3) and were discontinued. CC was increased 50 mg/day per cycle through 150 mg/day until ovulation occurred. Once the patient was ovulatory on therapy, a properly timed postcoital test and endometrial biopsy for luteal phase defect were performed. If anovulatory at 150 mg/day of CC or demonstrating abnormal postcoital test or endometrial biopsy at 150 mg/day of CC, patients were crossed to the other arm of the treatment protocol. The results revealed a significantly higher rate of ovulation (P less than 0.01) and conception (P less than 0.05) in the CC + DEX-treated group. When correlated with DHEA-S levels, this improvement occurred in patients with DHEA-S greater than 200 micrograms/dl (P less than 0.05).


American Journal of Obstetrics and Gynecology | 1980

Decidual production of prolactin in late gestation: Further evidence for a decidual source of amniotic fluid prolactin

Sanford M. Rosenberg; Ila A. Maslar; Daniel H. Riddick

The capacity of human decidual tissue to synthesize prolactin de novo throughout late gestation was investigated and correlated with the levels of prolactin (PRL) in amniotic fluid. Maximal concentrations of PRL in both amniotic fluid and samples of decidua were found prior to the thirtieth week of gestation and declined simultaneously until term. A high correlation (r = 0.90, p < 0.00005) was found when the levels of PRL in amniotic fluid and the initial (preincubation) content of PRL in decidua from the same patient were compared. A very high correlation (r = 0.96, p < 0.00005) was seen between the ability of the decidua to produce prolactin in vitro and the corresponding levels of prolactin in amniotic fluid. No significant difference in any parameter tested was noted with respect to either the sex of the fetus or the mode of delivery (p > 0.05). These data are interpreted as indicating (1) that decidual tissue varies throughout late gestation, in both its initial content of prolactin and its ability to synthesize prolactin de novo, in a manner which correlates to a high degree with variations in amniotic fluid prolactin levels and (2) that the decidual tissue is the major source of amniotic fluid prolactin.


Fertility and Sterility | 1983

Endometrial biopsy during treatment of luteal phase defects is predictive of therapeutic outcome

Douglas C. Daly; Clifford A. Walters; Carlos E. Soto-Albors; Daniel H. Riddick

Luteal phase deficiency (LPD), as diagnosed by endometrial biopsy, is not a single disorder but rather a spectrum of dysfunction that reflects both endometrial cycle and ovarian cycle abnormalities. Forty-three patients were diagnosed as having LPD by two consecutive abnormal cycles. Seven patients (16%) with hyperprolactinemia received bromocriptine, and one hypothyroid patient received thyroid replacement. The remaining patients were treated sequentially with progesterone suppositories, clomiphene, the combination, and follicle-stimulating hormone and luteinizing hormone. If no conception occurred in 6 months on a given type of therapy, treatment was advanced. Patients were rebiopsied on each medication. In all, 33 of 41 (81%) compliant patients conceived. No viable pregnancies occurred without normal endometrial maturation, regardless of the treatment modality employed. When compared with time-life table projections, pregnancies occurred at rates comparable to those of a normal population once normal endometrial maturation was obtained with therapy. The endometrial biopsy accurately reflects the functional state of both the ovarian cycle and the endometrial cycle and can be used to determine adequacy of therapy, thereby improving conception rates in patients with LPD and eliminating the need for therapeutic trials.


Fertility and Sterility | 1983

Hysteroscopic metroplasty: surgical technique and obstetric outcome

Douglas C. Daly; Clifford A. Walters; Carlos E. Soto-Albors; Daniel H. Riddick

Congenital Müllerian abnormalities, particularly the septate uterus, may result in recurrent abortion or premature labor. Twenty-five patients found to have a septate uterus during evaluation for infertility or recurrent abortion were treated by hysteroscopic metroplasty with laparoscopic visualization. Surgical outcome was excellent, intraoperative and postoperative morbidity was negligible, and the postoperative course was similar to that following laparoscopy alone. Preoperative fetal wastage in 17 previously fertile patients was 90%. Of 11 patients, 6 or more months postoperatively, 10 had conceived: 5 delivered vaginally at term, 2 delivered by cesarean section, and 2 pregnancies are in progress. One pregnancy miscarried at 21 weeks secondary to an incompetent cervix. With hysteroscopic metroplasty, septa can be incised successfully with lower morbidity and as good a surgical outcome as with abdominal procedures. If further studies confirm the pregnancy outcome reported, then hysteroscopic metroplasty should become the treatment of choice for the septate uterus.


American Journal of Obstetrics and Gynecology | 1981

Prolactin production by luteal phase defect endometrium

Douglas C. Daly; Ila A. Maslar; Sanford M. Rosenberg; Narendra Tohan; Daniel H. Riddick

The production of prolactin (PRL) by explants of late secretory endometrium obtained during normal cycles (n = 61) and that by similar explants obtained during luteal phase deficient (n = 17) cycles was compared. The amount of prolactin produced in vitro correlated with the degree of histologic decidualization in both normal and luteal phase defect endometria. However, samples of luteal phase defect endometrium produced significantly less prolactin (p less than 0.01) than did control tissues of the same ideal menstrual dates. These data indicate that the amount of prolactin produced by late secretory endometrium in explant culture can be used as an additional criterion for the diagnosis of luteal phase defects and may also provide a method for evaluating the response of the endometrium to progesterone.


American Journal of Obstetrics and Gynecology | 1983

Human myometrium: A new potential source of prolactin

Clifford A. Walters; Douglas C. Daly; Jane Chapitis; Sally Kuslis; Jerilynn C. Prior; William F. Kusmik; Daniel H. Riddick

Human myometrium is shown for the first time to produce prolactin in vitro. This prolactin is similar to pituitary prolactin by criteria of immunologic identity, gel chromatography and bioassay. The de novo synthesis of myometrical prolactin is supported by no detectable prolactin in initial tissue homogenate, nondetectable prolactin production during the first 24 hours of culture, cycloheximide inhibition of prolactin production with recovery of production in control medium, and tritiated leucine incorporation into prolactin. Although human myometrium is capable of producing prolactin without the addition of exogenous hormones, the addition of estrogen and progesterone, respectively, enhances and suppresses prolactin production in contrast to decidualized human endometrium where opposite effects on prolactin production are found.


Fertility and Sterility | 1977

Comparison of Polyglactic and Polyglycolic Acid Sutures in Reproductive Tissue

Daniel H. Riddick; Camillo T. DeGrazia; Ronald M. Maenza

Polyglactic acid and polyglycolic acid suture materials were compared in rat uterine and abdominal wall tissues for inflammatory response and tissue fibrosis. By 90 days after surgery, the tissue inflammatory reaction and fibrosis were significantly less in response to polyglactic acid suture (Vicryl) in both uterus and skin as compared with the response to polyglycolic acid (Dexon). In addition, the over-all tissue response in skin was significantly greater than that in uterus for both suture materials. The potential importance of tissue fibrosis--particularly in oviductal surgery, over and above the formation of adhesions between one organ and another--is emphasized. It is concluded that (1) the magnitude of tissue response to suture material varies for different tissues, (2) the degree of tissue wall fibrosis does not necessarily correspond to external tissue adhesions, (3) adhesions are maximal at the surgical knots regardless of the suture material used, and (4) polyglactic acid suture material may be preferable to polyglycolic acid suture material for infertility surgery, in which a minimum of tissue reaction is imperative.

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Douglas C. Daly

University of Connecticut

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Ila A. Maslar

University of Connecticut

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Narendra Tohan

University of Connecticut

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Sally Kuslis

University of Connecticut

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