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1.
Clin Chim Acta ; 271(1): 25-44, 1998 Mar 09.
Article in English | MEDLINE | ID: mdl-9564555

ABSTRACT

We describe simple modifications to the ICON II hCG (URINE) pregnancy test to provide a sensitive and specific urinary assay for hCG in field studies of fetal loss. The modified assay had a qualitative lower limit of detection of 0.30 IU/l, a 50% qualitative limit of 0.61 IU/l, a 100% qualitative limit of 1.16 IU/l, and a quantitative limit of 0.80 IU/l. Coefficients of variation ranged from 9.9% to 21.1%. Parallelism was observed among serially diluted subject samples. We used the assay in an 11-month prospective study of fetal loss in rural Bangladesh in which urine samples were collected twice-weekly from 494 women; 330 pregnancies and 93 fetal losses were detected. The median time to a positive pregnancy diagnosis was day 26 from last menses. The modified assay provided qualitative detection of early pregnancy comparable to laboratory assays, and appears to be well suited for use in epidemiologic or rural-population fetal loss studies.


Subject(s)
Chorionic Gonadotropin/urine , Fetal Death/epidemiology , Pregnancy Tests, Immunologic/methods , Adult , Analysis of Variance , Bangladesh , Female , Humans , Immunoassay/methods , Menstruation/physiology , Middle Aged , Pregnancy , Reagent Kits, Diagnostic , Reference Standards , Sensitivity and Specificity , Time Factors
2.
J Endocrinol ; 139(2): 307-15, 1993 Nov.
Article in English | MEDLINE | ID: mdl-7905917

ABSTRACT

The average concentration of GH in blood is high at birth and declines during the period of sexual maturation in bulls. The objectives of these studies were (1) to define age-related changes in vivo in the pulsatile secretion of GH from birth to puberty, (2) to determine whether pituitary cell content of GH and characteristics of the secretion of GH in vitro reflect age-related changes in vivo, and (3) to examine whether responsiveness to GH-releasing hormone (GHRH) and somatostatin (SRIF) in vitro changed with age in Holstein bull calves. In experiment 1, calves were bled every 15 min for 12 h at < 1, 12 and 42 weeks of age (n = 5/group), these being representative of infantile, juvenile and pubertal stages of development. Calves were killed 3 to 5 days later and the pars distalis of the anterior pituitary gland was enzymatically dispersed into a suspension of single cells. Aliquots of cells were extracted with 0.01 mol NaHCO3/l to determine the content of GH and cultured for 18 and 72 h. As expected, the average concentration of GH in plasma decreased with age (P < 0.001). The initial decrease in GH was caused by a reduction in the baseline concentration between birth and 12 weeks of age. There was a marked decrease in GH pulse amplitude between 12 and 42 weeks of age and a further reduction in the baseline concentration. In contrast, the pulse frequency of GH increased (P < 0.05) from < 1 week to 12-weeks of age and remained constant thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Aging/physiology , Cattle/physiology , Growth Hormone/metabolism , Pituitary Gland/metabolism , Animals , Flow Cytometry , Growth Hormone/blood , Growth Hormone-Releasing Hormone/pharmacology , Male , Organ Culture Techniques , Pituitary Gland/drug effects , Radioimmunoassay , Somatostatin/pharmacology
3.
Endocrinology ; 130(2): 811-8, 1992 Feb.
Article in English | MEDLINE | ID: mdl-1733728

ABSTRACT

Secretion of PRL in sheep is affected by photoperiod being highest during the spring and summer, lowest in fall and winter. The objectives of this study were to determine if 1) the production of variant forms of PRL, and 2) immuno- and bioactivities of PRL (iPRL and bPRL) differ during times of the year selected to represent periods of low, transitional and high PRL secretion. Twelve mature rams were maintained on pasture and killed in October, December, and April (n = 4/month). Individual pituitary glands were dispersed, cells obtained, and fixed for immunocytochemical flow cytometry, extracted with 0.01 N NaHCO3 or cultured in serum-free, defined media. The Mr of PRL extracted from cells immediately following dispersion ranged from 14-140K, with significantly more bands greater than 40K being detected from rams sacrificed in December than from those killed in October and April (P less than 0.01). No bands of PRL greater than 25K were observed when samples were reduced with beta-mercaptoethanol prior to electrophoresis, indicating that the high Mr forms were disulfide-linked aggregates. Culture media from October and April contained variants of PRL that ranged from 22-40K but those greater than 25K were generally not observed from cells harvested during December. Extracts of cells after 24 h in culture contained fewer high Mr species during December than had been present in initial extracts from that month. In contrast, during April more high Mr intracellular forms were present after culture than had been detected prior to culture during that month. The percentage of lactotrophs averaged 50.0 +/- 2.5, 47.4 +/- 5.7, and 59.4 +/- 5.5 for October, December, and April, respectively. Initial lactotroph content (pg/lactotroph) of iPRL was higher (P = 0.06) in April (46.0 +/- 17.0) when compared to October and December (8.0 +/- 2.0 and 20.0 +/- 10.0, respectively). In contrast, the bPRL content of initial extracts was higher (P = 0.05) in December (267.0 +/- 68.0) than in October (101.0 +/- 35.0), but not than in April (190.0 +/- 70.0). Although iPRL and bPRL concentrations in culture media were similar for the 3 months, the intracellular iPRL (P less than 0.001) and bPRL (P less than 0.0001) content after culture was greatest during April. In summary, in addition to the well-documented seasonal changes in blood concentrations of PRL, different molecular forms of PRL were found within the pituitary at different times of the year and seasonal variations in iPRL and bPRL did not occur in parallel.


Subject(s)
Pituitary Gland, Anterior/physiology , Prolactin/isolation & purification , Animals , Blotting, Western , Cells, Cultured , Culture Media , Electrophoresis, Polyacrylamide Gel , Genetic Variation , Male , Molecular Weight , Prolactin/genetics , Seasons , Sheep
4.
J Anim Sci ; 70(1): 232-42, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1582911

ABSTRACT

This study investigated the responsiveness of the pituitary-ovarian axis of prepubertal gilts to hourly injections (i.v.) with GnRH. Six gilts each at 70, 100, 150, and 190 d of age were assigned either to treatment with GnRH or saline. Treatments were given until gilts showed estrus or for 7 d, whichever came first. Hourly pulsing with GnRH resulted in gradually increasing concentrations of estradiol-17 beta (E2), a preovulatory surge of LH, and subsequently increased progesterone (P4) concentrations. The increase in serum P4 was preceded by ovulation and corpora lutea (CL) formation in two gilts 70 d of age and all older gilts. The interval (h) from start of GnRH treatment to peak E2 (88 +/- 3), peak LH (103 +/- 3), and concentrations of P4 greater than or equal to 1 ng/mL (144 +/- 4) did not differ (P greater than .50) for 18 gilts between 100 and 190 d of age. In two ovulating, 70-d-old gilts, the interval from onset of GnRH treatment to peak E2 (171 +/- 6), peak LH (186 +/- 0), and P4 greater than or equal to 1 ng/mL (216 +/- 4) was lengthened (P less than .001). Peak concentrations of E2 (pg/mL) were higher (P less than .01) at 190 d (48 +/- 2) and 150 d (49 +/- 2) than at younger ages and lower (P less than .01) in gilts 70 d of age (31 +/- 1) than in gilts 100 d of age (41 +/- 2). Peak LH (nanograms/milliliter) was higher (P less than .01) in gilts 100 d of age (12.7 +/- 6) than in older gilts. Concentrations of P4 were similar (P greater than .20) for all ovulating gilts. The number of CL (12.7 +/- .7) did not differ (P greater than .20) for 18 gilts 100 d of age or older but was higher (P less than .01) than that (4.5 +/- 1.1) for two gilts 70 d of age. Corresponding endocrine responses or ovulations were not observed in four 70-d-old gilts treated with GnRH or in gilts given saline. These findings indicate that the functional integration of the pituitary-ovarian axis is completed between 70 and 100 d of age. Hourly treatment with GnRH is an adequate stimulus to induce ovulation in prepubertal gilts as early as 70 d of age. Also, the number of follicles reaching ovulatory competency was similar (P greater than .20) in gilts between 100 and 190 d of age, when GnRH was given on a BW basis.


Subject(s)
Aging/physiology , Gonadotropin-Releasing Hormone/pharmacology , Hormones/blood , Ovulation/drug effects , Swine/physiology , Animals , Estradiol/blood , Estrus/drug effects , Female , Gonadotropin-Releasing Hormone/administration & dosage , Luteinizing Hormone/blood , Progesterone/blood , Sexual Maturation
5.
Health Phys ; 55(2): 169-73, 1988 Aug.
Article in English | MEDLINE | ID: mdl-3410683

ABSTRACT

Three areas are targeted as offering major challenges to the health physicists of the future. One area is in the influx of new technologies, such as laser isotope separation (LIS) and its resultant impact on dosimetry. The LIS process, while generally reducing exposures, also has side effects that make it difficult to detect internal Pu contamination with present methods. Specifically, the LIS process will remove the 241Pu and its 241Am decay product, which is the estimator for Pu, from the 239Pu stream. A second area involves the requirements now being developed for waste management, which also challenges health physicists by insisting upon safe environments for workers who handle waste products while mandating confirmation and cleanup of hazardous wastes. Thus, developing remote inspection techniques will be vital for personnel protection. Finally, military health physicists are faced with the challenges posed to the civilian professionals as well as challenges unique to the military, such as the education of future health physicists to meet the complex military needs.


Subject(s)
Military Personnel , Radiation Protection , Radioactive Waste , Health Physics , Humans , Radiation Monitoring , Radiation Protection/standards , Radiometry/methods , Safety , United States
6.
Am J Vet Res ; 48(1): 45-50, 1987 Jan.
Article in English | MEDLINE | ID: mdl-3826841

ABSTRACT

Gilts were treated during midgestation with prostaglandin (PG) F to study the efficacy of different treatment regimens on induction of abortion and to determine the adverse consequences of PGF-induced abortion in swine. In study 1, pregnant purebred Duroc gilts (60 to 90 days of gestation) were given (IM) 500 micrograms of cloprostenol (n = 12), 20 mg of dinoprost tromethamine (n = 11), or 10 mg of dinoprost tromethamine repeated 12 hours later by an additional 10 mg of dinoprost tromethamine (n = 11). The percentage of gilts that aborted and percentage of aborted gilts that returned to estrus for each treatment group were as follows: cloprostenol, 91.7% and 100%, respectively; 20 mg of dinoprost tromethamine, 36.4% and 25.0%, respectively; and 10 + 10 mg of dinoprost tromethamine, 100% and 90.9%, respectively. Treatment with cloprostenol and with 10 + 10 mg of dinoprost tromethamine caused more gilts to abort (P less than 0.01) than did treatment with 20 mg of dinoprost tromethamine. Gilts that did not abort were given a second treatment with 10 + 10 mg of dinoprost tromethamine. When the abortions by gilts initially treated with 500 micrograms of cloprostenol or 10 + 10 mg of dinoprost tromethamine were combined with those re-treated with 10 + 10 mg of dinoprost tromethamine, 32 of 33 (97.0%) gilts aborted, and 30 of the 32 (93.8%) aborted gilts returned to estrus.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Abortifacient Agents, Nonsteroidal/pharmacology , Abortifacient Agents/pharmacology , Abortion, Induced/veterinary , Abortion, Veterinary/chemically induced , Dinoprost/analogs & derivatives , Pregnancy, Animal/drug effects , Prostaglandins F, Synthetic/pharmacology , Swine Diseases/chemically induced , Animals , Cloprostenol/pharmacology , Estradiol/blood , Estrus/drug effects , Female , Luteinizing Hormone/blood , Pregnancy , Progesterone/blood , Swine , Swine Diseases/blood , Swine Diseases/physiopathology
7.
Biol Reprod ; 32(5): 1191-9, 1985 Jun.
Article in English | MEDLINE | ID: mdl-4016175

ABSTRACT

The role of prolactin during sexual maturation in male golden hamsters was studied. Controls (n = 23) received vehicle and treated animals (n = 23) received 500 micrograms 2-bromo-alpha-ergocryptine (CB154) daily from 10 days of age until 4 or 5 wk of age. Serum prolactin in prepubertal male hamsters was reduced to a nondetectable level by treatment with the dopamine agonist CB154. Flank gland diameter, body weight, testicular and total accessory sex organ weights, and serum testosterone were all significantly lower (P less than 0.05) in the CB154-treated animals. In addition, seminiferous tubule area, seminiferous tubule luminal and cellular areas, and number of late spermatids per tubule cross-section were significantly reduced (P less than 0.01) in CB154-treated prepubertal males. Thus, the absence of prolactin retarded sexual maturation in male golden hamsters. These data suggest, that prolactin enhances testosterone production during the process of sexual maturation and supports the development of androgen-dependent tissues.


Subject(s)
Bromocriptine/pharmacology , Prolactin/blood , Sexual Maturation/drug effects , Aging , Animals , Body Weight/drug effects , Cricetinae , Genitalia, Male/anatomy & histology , Male , Mesocricetus , Organ Size/drug effects , Seminiferous Tubules/anatomy & histology , Sperm Count , Spermatids/cytology , Testis/anatomy & histology , Testosterone/blood
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