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Biomedical subjects

L A Lavia

Publications and source records attributed to L A Lavia.

13 recordsLinked to original sources
PubMed1991

The prognostic value of image analysis in ovarian cancer.

Histologic grading is very important for treatment decisions in ovarian cancer. All grading systems contain a significant subjective component, which could be reduced by including objective measurements into the diagnostic decision. Image analysis was used to determine nuclear area and ploidy distributions in 42 patients with epithelial ovarian cancer, and the results were related to tumor grade and clinical outcome. The mean nuclear area, mean optical density, number of hyperploid cells, and the standard deviation between measurements were significantly higher in Grade 2 and 3 tumors compared with Grade 1 tumors, in rapidly progressive tumors compared with less aggressive malignancies, and in recurrent tumors compared with primary lesions. The number of nuclei with very high DNA content was found to be of prognostic importance. Image analysis thus provides additional prognostic information in epithelial ovarian cancer.

DNA, Neoplasm↗
PubMed1991

Rat endometrial stromal-epithelial response to estrogen infusion.

Morphologic changes at the interface of rat endometrial luminal epithelial cells and the stromal cells immediately adjacent were examined and correlated with hypertrophy of the epithelial cells during estradiol (E2) infusion (1 microgram E2/24 h). While the lamina densa in castrate endometrium was thread-like, it became thicker and apparently more granular in some areas below the luminal epithelium during E2 infusion. However, no changes were seen in the intensity of laminin-like immunoreactivity at various time points up to 96 hours after beginning infusion, suggesting that these alterations were due to changes in nonlaminin components. The stromal cells adjacent to the basal lamina in the castrate state had cell processes extending toward the epithelium that terminated on the basal lamina. Under estrogen infusion, stromal cell bodies migrated close to and became oriented along the basal lamina. No interruptions were seen in the lamina densa or in the laminin-like immunoreactivity in the basal lamina. Thus, there were no direct morphologic interactions between epithelial and stromal cells induced by estrogen. Some of the stromal cells developed a dilated rough endoplasmic reticulum and some developed multiple elaborate processes within 41 hours after minipump implantation. Within 28 hours, nuclear hypertrophy had occurred in 15% of the epithelial cell layer. If interactions occur between stromal and epithelial cells, and morphologic evidence presented here suggests they do, then all such interactions are through an intact lamina densa-laminin layer, and any chemical mediators affecting cells on opposite sides of the lamina densa must migrate through it.

Animals↗
PubMed1989

Changes in nuclear and nucleolar areas of endometrial glandular cells throughout the menstrual cycle.

Reproducible measures of the ultrastructural changes occurring throughout the normal human menstrual cycle are useful for defining and differentiating between normal and pathological states. Glandular endometrial functionalis epithelium obtained from five menstrual cycle subphases (early and late proliferative; and early, middle and late secretory) has been quantitated and compared for changes in nuclear and nucleolar size. These analyses indicate that (a) nuclear area significantly increases in the late secretory subphase, perhaps a requirement of endometrial regeneration; (b) nucleolar area peaks during the early secretory subphase, a necessary prelude for the later increased secretory activity; and (c) nucleolar area declines in the middle and late secretory subphases, probably due to falling hormone blood levels late in the cycle. In the proliferative phase, the majority of cells containing large nuclei and nucleoli have a relatively undeveloped cytoplasm, while the cytoplasm of those in the secretory phase contains glycogen. These cells were termed Stage 1 and 2 cells, respectively. The late secretory subphase contains some degenerating mature epithelial cells with large nuclei and small nucleoli as well as differentiated and regenerating cells with larger nucleoli. These measures establish a baseline of the normal changes in nuclear and nucleolar size as they occur throughout the normal human menstrual cycle.

Biopsy↗
PubMed1988

Ultrastructural evidence of stromal/epithelial interactions in the human endometrial cycle.

We found ultrastructural evidence of interactions between glandular epithelium and superficial stromal cells of the human endometrium during phases of the menstrual cycle. Four significant changes were observed in the transition from early proliferative (days 5 to 9) to early secretory (days 15 to 19) phases. These changes included: (1) an increase in the number and size of lamina densa disruptions, (2) an increase in the number and size of gap junctions, (3) an increase in the number and complexity of epithelial cell projections that extended through the lamina densa, and (4) an increase in close contacts between stromal and epithelial cells. The complex epithelial cell projections that extended through the lamina densa were in close proximity to stromal cells. These interactions were seen primarily in the early secretory phase. After that time (days 20 to 28) the interactions were less frequent. These morphologic results reveal complex physical interactions between epithelial and stromal cells of the adult endometrium. The interactions reach maximal development during the preimplantation phase of the endometrial cycle.

Adult↗
PubMed1986

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↗
PubMed1985

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↗
PubMed1984

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↗
PubMed1984

Rat uterine polyamine biosynthetic decarboxylase activities following multiple injections of estradiol-17 beta and/or estriol.

A single injection of 0.5 micrograms estradiol-17 beta (E2) plus 0.5 micrograms estriol (E3) stimulated a different pattern in 22-24 day-old rat uterine ornithine decarboxylase (ODC) and S-adenosyl methionine decarboxylase (SAMDC) activities than was induced by either a single injection of 0.5 micrograms E2 or multiple injections of 0.5 micrograms E3. Differences included alterations in enzyme activity peak timing as well as activity duration. Every 3 hour injections of 0.05 micrograms E2 induced maximum uterine ODC activity at 4, 24, 32, and 40 hours, intermediate activity at 48, 64, and 72 hours as well as a small peak by 56 hours. When 0.05 micrograms E2 plus 0.05 micrograms E3 were injected simultaneously every 3 hours, the ODC activity pattern was similar except that activity fell to intermediate levels by 40 hours. It is suggested that E3 alterations of E2 induced uterine enzyme activities (when monitored at frequent intervals) could be physiological alterations in uterine growth responses due to E2-E3 hormone interactions. However, there appeared to be no differences between E2 or E2 plus E3 induction of DNA synthesis and luminal epithelial cell height and cross-sectional area or ODC and SAMDC activities when measured at 24, 48, or 72 hours.

Adenosylmethionine Decarboxylase↗
PubMed1984

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↗
PubMed1983

Polyamine biosynthetic decarboxylase activities following estradiol-17 beta or estriol stimulation of the immature rat uterus.

Following a single intraperitoneal injection of 0.5 microgram estradiol-17 beta (E2) into immature female rats uterine ornithine decarboxylase (ODC) activity increased to a peak at 4 hours postinjection. It decreased to intermediate levels by 6 hours and remained elevated until returning to control levels by 18 hours. When either 0.5 microgram estriol (E3) or 0.05 microgram E2 was injected, activity increased to a 4 hour ODC peak then decreased to control levels by 10 hours. The decrease to intermediate levels of ODC activity after dosing with 0.5 microgram E2 occurred at the same time activity decreased to control levels following treatment with either 0.05 microgram E2 or 0.5 micrograms E3. S-Adenosyl methionine decarboxylase (SAMDC) activity had increased by 4 hours following an injection of 0.5 microgram E2 and remained elevated until 16 hours then decreased to control levels. An injection of 0.05 microgram E3 stimulated only a 4 hour peak after which time SAMDC decreased to control levels by 14 hours. After an injection of 5.0 microgram E2 SAMDC activity had increased by 4 hours and remained elevated for the remainder of the experiment (16 hours). Decreases in ODC activity following 4 and 10 hours may reflect a decrease in nuclear estrogen receptor levels. The ODC activity seen here following 0.5 microgram E2 injection is similar in timing to that seen in other proliferating systems and may be due to a common mechanism.

Adenosylmethionine Decarboxylase↗
PubMedDate not supplied

Induction of nucleolar changes in rat luminal cells by single injection or low-dose infusion of estradiol.

The nucleolar area of rat uterine luminal epithelial cells was measured for 41 h after beginning either of two dosage regimens of estradiol (E2): a single injection of 1.0 microgram E2 or a continuous infusion of E2 at a rate of 1.0 microgram/24 h. In response to a single injection of E2, mean nucleolar area was significantly elevated above control levels by 10 h. Nucleolar morphology showed slight changes, but the fibrillar component was always associated with 2-3 fibrillar centers by 10 h. In response to a continuous infusion of E2, mean nucleolar area was elevated by 10 h, reached a maximum by 18 h, and remained relatively constant thereafter. Nucleolar morphology showed significant changes by 10 h; the fibrillar component was commercially denser. Bivariate histograms of nuclear versus nucleolar areas showed a bimodal distribution after both injection and infusion, suggesting that two size classes of nuclei existed after estrogen stimulation. The results suggest that: 1) a continuous infusion of E2 at a rate of 1.0 microgram/24 h was more effective in inducing larger increases in nucleolar area and transcription than a single injection of 1.0 microgram E2 at time 0; 2) using analysis of nuclear and nucleolar areas two subpopulations of cells were identified; and 3) continuous infusion of E2 produced a steady state of ribosome production and cytoplasmic transport by 18 h.

Animals↗