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D K Roberts

Publications and source records attributed to D K Roberts.

At least 55 records · Page 3Linked to original sources

Iris microhemangiomas.

Iris microhemangiomas (IM) are benign proliferations of small, twisted blood vessels along the pupillary margin. They are usually bilateral and appear to be developmental in nature. IMs most commonly occur in patients with myotonic dystrophy and adult-onset diabetes mellitus, but have also been associated with respiratory disease, congential heart disease, and central retinal vein occlusion. Additionally, they may be found in individuals without obvious ocular or systemic abnormality. The etiology remains obscure. In this report, illustrative cases are followed by a brief discussion outlining typical clinical manifestations, etiological considerations, and possible implications.

Aged↗

The value of endocervical curettage in the management of the patient with abnormal cervical cytologic findings.

Patients with adequate colposcopic examinations and dysplasia on the endocervical curettage specimen usually undergo further diagnostic evaluation. This study evaluated 712 patients and found the frequency of positive endocervical curettage specimens to be 17.6%. Cervical conization or hysterectomy specimens were examined in 66 cases with a positive endocervical curettage. Of these, 69.7% had histologic evidence of discontinuous dysplasia in the endocervical canal. The endocervical curettage specimens were grouped by the percentage of endocervical epithelium that was dysplastic: group 1, less than 10%; group 2, 10% to 50%; group 3, greater than 50%. Confirmed histologic endocervical involvement was 80%, 56%, and 60%, respectively. The involvement of the endocervical canal also increased with increasing grade of cervical intraepithelial neoplasia. Of the 66 cases examined with positive endocervical curettage specimens, 62.1% had grade 3 cervical intraepithelial neoplasia on the ectocervix. Seven patients had positive endocervical margins, with six of these occurring in grade 3 cervical intraepithelial neoplasia lesions. Two unsuspected cases of cervical malignancy were identified by endocervical curettage.

Carcinoma↗

Effects of cryopreservation on the motility characteristics of human spermatozoa.

Ejaculates (164) were obtained from 17 donors serving on an artificial insemination by donor panel. Semen analysis was performed before and after freezing by an integrated microcomputerized system employing the multiple-exposure photography (MEP) method. Sperm count, motility, velocity, motility index (MI; product of the sperm velocity and percentage of motile spermatozoa) and motile density (MD) were determined for each ejaculate. After the initial evaluation the ejaculates were frozen in liquid nitrogen, thawed 24 h later, and assessed for post-thaw motility, velocity, MI and MD. The mean +/- s.e. sperm count and volume for this group of donors was 148 +/- 4 x 10(6)/ml and 3.1 +/- 0.1 ml, respectively. Mean +/- s.e. values obtained from the prefreeze analysis were: motility = 64 +/- 1%, velocity = 30 +/- 0.4 microns/sec, MI = 19 +/- 0.5 microns/sec and MD = 94 +/- 3 x 10(6)/ml. Post-thaw analysis revealed a significant reduction (P less than 0.01) in all values measured. Motility was reduced to 27 +/- 1%, MI was reduced to 5 +/- 0.3 microns/sec, and MD was reduced to 33 +/- 1 x 10(6)/ml. Velocity was the least affected by cryopreservation, being reduced to 21 +/- 0.5 microns/sec (P less than 0.01). Cryopreservation resulted in a marked shift in the frequency distribution of sperm motility and motility index towards subnormal values while in the majority of ejaculates velocity and motile density were maintained in the normal range. Significant differences were noted amongst donors in the percentage change of the various semen measures as a result of cryopreservation. When within-subject coefficients of variation were calculated, velocity was the least variable parameter.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Count↗

Application of a bovine cervical mucus penetration test.

One hundred seventy-eight ejaculates obtained from infertility patients were evaluated by routine semen analysis and by a bovine cervical mucus penetration test (BCMPT). A significant correlation (p less than 0.01) was observed between mucus penetration and both sperm count (r = 0.349) and sperm motility (r = 0.394). One hundred fifty-two of 178 patients (85%) had normal sperm counts (greater than 20 x 10(6)/ml). Of these patients, 68% had good (greater than 30 mm), 26% had questionable (21-30 mm), and 7% had abnormal (less than 20 mm) penetration values. One hundred sixty-one of 178 patients (90%) had normal sperm motilities (greater than 40%). Of these patients, 71% had good, 25% had questionable, and 4% had abnormal penetration values. Conversely, 46% and 18% of patients with abnormal sperm count and motility, respectively, had normal penetration values (greater than 30 mm). A significant relationship (p less than 0.05) was observed between the BCMPT and pregnancy problems not apparent by semen analysis data, and may prove to be a useful adjunct to the use of routine semen analysis in evaluating male fertility.

Animals↗

Microhemorrhagic maculopathy associated with aerobic exercise.

Microhemorrhagic maculopathy is a condition characterized by the spontaneous appearance of a small, unilateral macular hemorrhage in apparently healthy individuals. In most cases, no cause if found; however, transient stress to the vascular system via a Valsalva maneuver is sometimes associated with its occurrence. This is referred to as Valsalva hemorrhagic retinopathy. In addition to Valsalva stress, other factors such as hematologic disorders, adverse effects of systemic medications, or genetic influences may play a role. In this paper, a case of Valsalva hemorrhagic retinopathy associated with aerobic exercise is presented; its mechanism is discussed; and other factors which may contribute to the formation of microhemorrhagic maculopathy are reviewed.

Adult↗

Effect of a parafoveal microlesion made with an argon laser on smooth-pursuit eye movements of monkeys.

The significance of the parafoveal region in processing information about target velocity to initiate ocular pursuit was evaluated by making a small paracentral scotoma in monkeys trained to pursue a slowly moving target. In the experimental paradigms in which the image had to cross the scotoma, the small retinal lesion (greater than 2 degrees) gave a direct effect upon the ability of monkeys to pursue the target motion. The abnormal pursuit was characterized by a marked reduction of eye velocity. Evaluated from the initial portion of the pursuit immediately following the first corrective saccade, the eye velocity was as low as 50 to 60% of the target velocity. The abnormality was more pronounced in slow pursuit (15 to 20 degrees/s) than in fast pursuit (25 degrees/s). The data indicated that the small retinal region at the boundary of the macula plays an important role in sampling target velocity during the initial part of smooth-pursuit eye movement.

Animals↗

Nucleolar canalicular structure in extrauterine endometriosis.

Under the influence of progesterone the unique intranuclear structure known as the nucleolar canalicular structure (NCS) develops in the human endometrium. This organelle was not described previously outside the uterus. In this report the cases of two patients in whom the NCS appeared in extrauterine endometriosis are presented.

Adult↗

Dysgerminoma in the differential diagnosis of hydatidiform mole.

Serum measurements of beta-human chorionic gonadotropin (beta-hCG) for pregnancy tests are now positive at very low levels (25 mIU/mL). Sonography is the diagnostic method of choice for patients with the possibility of intrauterine trophoblastic disease. A case is reported in which ultrasound confused an ovarian neoplasm for a hydatidiform mole; a low level of hCG produced by the dysgerminoma corroborated the diagnosis. The tumor with syncytiotrophoblastic giant cells is described, and a differential diagnosis for minimally elevated hCG is discussed. This case represents an example of dysgerminoma presenting with ascites (stage IC).

Adolescent↗

Differential diagnosis of spontaneous hyphema associated with central retinal vein occlusion.

Spontaneous hyphema refers to a nontraumatic hemorrhage in the anterior chamber. It is uncommon and may result from such conditions as rubeosis iridis, intraocular neoplasms, blood dyscrasias, severe iritis, fibrovascular membranes in the retrolental or zonular area, and vascular anomalies of the iris. A case is presented describing a spontaneous hyphema occurring as a result of iris neovascularization in a patient who suffered from occlusion of the central retinal vein. Spontaneous hyphema and the presenting ocular conditions as they pertain to its occurrence are discussed.

Aged↗

Nuclear and nucleolar areas: a quantitative assessment of endometrial neoplasia.

Quantitative methods were used to determine ultrastructural area differences in nuclei and nucleoli of normal proliferative endometrium as well as grades 1, 2, and 3 adenocarcinomas. Nuclear area distribution curves differed significantly among all groups. No significant differences were observed between nucleolar area distribution curves of normal proliferative and grade 1 adenocarcinomas. However, significant differences were found among distribution curves of all other groups. The computer-assisted high resolution ultrastructural examination provides a sensitive means of evaluating differences in nuclear and nucleolar areas of cells in normal and cancerous states.

Adenocarcinoma↗

Rat luminal cell nuclear area changes correlated with uterine growth responses induced by a low dose infusion or injection of estradiol-17 beta.

Rat uterine luminal epithelial cells (LEC) responded differently when exposed to an injection of 1.0 microgram estradiol-17 beta (E2) compared to a continuous infusion of E2 at the rate of 1.0 microgram/24 hours. After injection or beginning infusion, LEC mean nuclear area significantly decreased by 4 h, then increased thereafter. After injection, nuclear area distributions were determined at each time point. The percentage of large nuclei (greater than 40 mu 2) decreased by 4h postinjection and remained a relatively small proportion of the population, while the percentage of nuclei of 20-30 mu 2 areas increased throughout the experiment. During infusion, the percentage of large nuclei decreased by 4h after pump implantation, then increased. Only infusion induced sustained, increased uterine protein content, DNA synthesis and ornithine decarboxylase activity. This study suggests that E2 treatment modality induces differences in nuclear size in target cells as well as in biochemical parameters.

Animals↗

Luteolysis induced by prostaglandin F2 alpha in the lizard, Anolis carolinensis.

The effect of exogenous prostaglandin F2 alpha (PGF) on luteal function and morphology was examined in the lizard, Anolis carolinensis. Reproductively active females were injected with 1.0 micrograms PGF, 0.1 micrograms PGF, or 0.05 ml saline. Animals were killed 2, 6, or 24 hr after injection. Prostaglandin treatment induced luteolysis as evidenced by significant decreases in plasma progesterone concentration in animals sacrificed 6 and 24 hr after treatment. Both doses of PGF were effective. However, 0.1 micrograms PGF induced luteolysis in less than 50% of the treatment group. Luteal degradation became apparent at the cellular level 24 hr after PGF treatment whereas no significant changes were observed in corpora lutea of the 2- or 6-hr postinjection specimens. These data suggest that PGF is a luteolytic agent in reptiles.

Animals↗

Uterine growth responses of the mature castrate rat to estradiol-17B.

To examine estrogen-stimulated uterine growth we have monitored changes in uterine DNA synthesis, ornithine decarboxylase (ODC) activity and protein content as well as luminal epithelial (LE) cell mitotic index and ultrastructural changes. We have utilized this model to examine castrate mature rat uterine growth as a function of time between 18 and 40 hours following a single injection of 25.0 ug of estradiol-17B. LE cell mitotic index and protein content increases were maximally elevated as early as 18 hours postinjection while uterine ODC activity was maximal at 28 hours; uterine DNA synthesis increases continued throughout the experiment. In addition, the infusion of either 1 or 2 ug E2 plus progesterone over a 24 hour period, stimulated elevated ODC activity under both treatment regimens and LE cell mitotic index which was inversely related to E2 dose.

Animals↗

An ultrastructural comparison of grade I and II endometrial adenocarcinoma considering estrogen and progesterone receptor status.

Eighteen (18) previously untreated patients with grade I (9) and II (9) endometrial adenocarcinoma provided endometrial samples for biochemical analysis of estrogen and progesterone receptors. The same samples were evaluated by histology and ultrastructure. Progesterone receptor negative samples (PR less than 1000 fmole/g tissue) showed more ultrastructural characteristics of malignancy and a wider range of changes than the progesterone positive specimens (PR greater than 1000 fmole/g tissue). These findings appeared to be independent of estrogen receptor status. No significant ultrastructural changes were seen when grades I and II were compared.

Adenocarcinoma↗