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D V Horbelt

Publications and source records attributed to D V Horbelt.

At least 19 recordsLinked to original sources
PubMed1999

Ultrastructural interactions in the microvasculature of human endometrial adenocarcinoma.

OBJECTIVES: Our purpose was to study the ultrastructural morphology of the microvasculature of human endometrial adenocarcinoma and to determine the effect of this malignancy on cell-to-cell communication between the components of the microvasculature and with the other tissue compartments of human endometrium. Methods. Multiple cases of human endometrial adenocarcinoma were studied and graded by light microscopy. Six cases of Grade I and six cases of Grade II were selected. Two blocks per case were studied ultrastructurally. RESULTS: In contrast to our expectation that the ultrastructure of tumor vessels would suggest a great deal of proliferation and new vessel formation, we found that tumor vessels displayed a high degree of cellular differentiation, in the form of numerous and varied cell-to-cell contacts, and large amounts of protein production. CONCLUSIONS: The morphology of the microvasculature of endometrial adenocarcinoma suggests an active rather than passive role in tumor vessels.

Adenocarcinoma↗
PubMed1996

Ultrastructure of the microvasculature in human endometrial hyperplasia.

OBJECTIVE: Our purpose was to determine the effect of hyperplasia on cell-to-cell communication in the microvasculature of the human endometrium. STUDY DESIGN: Ten biopsy specimens of simple and complex hyperplasia of the human endometrium were investigated by electron microscopy. RESULTS: The microvasculature of the hyperplastic endometrium shows morphologic disorder. The extracellular matrix is altered, and cell death is widespread. Intercellular contact is infrequent or absent. CONCLUSIONS: These results are in marked contrast to the ultrastructure of the normal microvasculature. The complex cell-to-cell interaction observed in normal tissue appears lost. This report, combined with others, indicates that cell-to-cell contact is sparse in hyperplastic endometrium.

Capillaries↗
PubMed1996

The nuclear channel system in endometrial adenocarcinoma exposed to medroxyprogesterone acetate.

The nuclear channel system (NCS), giant mitochondria and subnuclear glycogen form a triad of ultrastructural features observed in normal human endometrial epithelium in response to progestational steroids. Both the giant mitochondria and subnuclear glycogen have been described in endometrial adenocarcinoma, but the NCS has not. This article reports the development of the NCS in adenocarcinoma treated with medroxyprogesterone acetate. Previous studies suggest that the NCS in normal tissue is a response to the acyl group in the 17-beta position of the D-ring of some progestational steroids, such as medroxyprogesterone acetate. Medroxyprogesterone acetate was administered to 12 postmenopausal women with endometrial adenocarcinoma. Hysterectomies were performed 8 to 20 days after treatment. Pretreatment specimens were also obtained on 8 of the 12 patients. Using standard electron microscopy procedures, light microscopy on plastic semithin sections was first used to confirm the presence of tumor. Thin sections of malignant endometrium were prepared and evaluated ultrastructurally for progestational alterations. Abnormal giant mitochondria and subnuclear glycogen were found both before and after treatment. The third element of the triad, the NCS, was not observed in any of the available pretreatment biopsies, but was seen in three of the treated specimens. Thus it appears that the NCS is a response to the given progesterone therapy.

Adenocarcinoma↗
PubMed1994

Ultrastructural cell-to-cell interactions in hyperplastic endometrial stroma.

In hyperplastic endometrial stroma, cell-to-cell contacts are infrequent. Those that are present are not well developed and may appear degenerative. Significant amounts of extracellular matrix further impede contact. The cells of hyperplastic endometrial stromal are, for the most part, poorly differentiated and both apoptosis and necrosis are common. Fibroblast-like cells make up most of the increased cellularity, with few endometrial granulocytes or other cells types.

Apoptosis↗
PubMed1994

Stromal-epithelial communications in hyperplastic human endometrium.

OBJECTIVE: Our objective was to assess the cell-to-cell contacts in hyperplastic human endometrium and to compare them with contacts in normal endometrium. STUDY DESIGN: Hyperplastic endometrial samples (five with simple hyperplasia and five with complex hyperplasia) without atypia by light microscopy were studied with transmission electron microscopy. The cell-to-cell contacts, basal lamina, and epithelial-to-stromal compartment contacts were studied and compared with these same areas in normal endometrium. RESULTS: Only infrequent gap junctions between epithelial cells were seen. Other epithelial contacts were also greatly reduced when compared with normal epithelium. Cell-to-cell contacts between the epithelial compartment and the stromal compartment were rare and degenerative in configuration. An increase in extracellular matrix and various alterations in the basal lamina appears to contribute to a decrease in cell-to-cell contacts. CONCLUSIONS: Compared with normal endometrium, hyperplastic endometrium demonstrated far fewer cell-to-cell contacts. The basal lamina and extracellular matrix were altered in such a fashion that communication between the stromal and epithelial compartments appeared to be impaired. Stromal and epithelial cells rarely were in contact. Those contacts present were less complex and the majority were degenerative. Hyperplasia without atypia demonstrated a much lower amount of intercellular communication than normal endometrium.

Cell Communication↗
PubMed1992

Ultrastructure of the microvasculature in the human endometrium throughout the normal menstrual cycle.

In the early proliferative phase endometrial capillary basal lamina is loosely formed and discontinuous. It becomes more distinct in the late proliferative phase and develops whorled extensions that include pericytes in the early secretory to midsecretory phase. Throughout the cycle both endothelial cells and pericytes possess cytoplasmic processes that extend through discontinuities in the basal lamina and make contact with each other. These contacts may be simple or complex. They become more elaborate as the cycle progresses to the midsecretory phase. Endothelial cells show progressive but heterogeneous differentiation into the midsecretory phase, with individual cell hypertrophy. In the late-secretory phase the endometrial stroma and the basal lamina are characterized by widespread degeneration, and the cell-to-cell contacts sharply decrease. However, endothelial cells remain relatively intact.

Cytoplasm↗
PubMed1992

Cervical conization: cold knife and laser excision in residency training.

During a 2-year period, 293 consecutive conizations performed by residents in obstetrics and gynecology were reviewed. One hundred sixty-one patients underwent laser excision and 132 women were treated by cold knife conization. Average operating times for laser excision and knife conization were 31 and 33 minutes, respectively. Combined minor and major complication rates for laser and knife cones were 19 and 30%, respectively. Major complications including cervical stenosis and heavy bleeding were seen in 20% of knife conizations and 6% of laser excisions. Average blood loss for knife conization was 65 mL, and average blood loss for laser conization was 34 mL. Among those examined in follow-up with cervical cytology and colposcopy, no patient in the laser excision group showed evidence of persistent dysplasia, compared with one patient (3%) in the knife conization group. The reported data suggest no difference in operating time, length of anesthesia, or success of treatment between laser excision and knife conization performed by residents in training. Fewer complications were seen in the laser excision group.

Anesthesia, Obstetrical↗
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↗
PubMed1989

Experience with the Groshong long-term central venous catheter.

A study of the Groshong catheter in a gynecologic oncology population is presented, describing the catheter's ease of insertion, and patient acceptance and compliance in catheter care. From December 1985 through November 1987, 72 Groshong catheters were inserted in 67 patients. The Groshong differs from conventional Hickman-type catheters in design and maintenance. Thirty-two of 72 catheters (44%) were inserted under local anesthesia. The remaining catheters were inserted under general anesthesia at the time of major gynecologic procedures. None of the cases required fluoroscopy. The insertion technique is less traumatic than conventional approaches because of a stainless steel tunneling device. The median duration of use was 191 days. There were no cases of pneumothorax or catheter occlusion. Catheter removal was required in four cases with skin infection unresponsive to local therapy and in two cases with bacteremia. One patient developed thrombosis of the right subclavian vein but was treated without catheter removal. One patient with a skin infection at the exit site accidentally dislodged her catheter. The overall complication rate was 11% (8 of 72 cases).

Catheterization, Central Venous↗
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

Interaction of epithelial and stromal cells in vaginal adenosis.

Two types of direct contact between epithelial and stromal cells in patients with vaginal adenosis are documented in electron micrographs. In the first type, epithelial cells send cytoplasmic extensions through the basal lamina to achieve, at times, complete fusion with fibroblasts in the stromal compartment. In the second type, mast cells act as intermediaries between the epithelial and stromal compartments.

Epithelium↗
PubMed1987

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↗
PubMed1987

Perineal hernia repair using human dura.

A patient developed a large perineal hernia and prolapse of a myocutaneous neovagina 13 months after total pelvic exenteration for recurrent squamous cell cancer of the cervix and gracilis myocutaneous vaginal reconstruction. The neovagina was removed and the pelvic floor defect was repaired with preserved human dura. Twelve months postoperatively, the patient remained asymptomatic. Current and potential uses for human dura allografts are discussed.

Dura Mater↗
PubMed1986

Complications of extended-field therapy for cervical carcinoma without prior surgery.

This study is designed to analyze the complications of extended-field radiotherapy for carcinoma of the uterine cervix uncomplicated by recent prior surgery. Forty-two patients with carcinoma of the uterine cervix and lymph node metastases established by unequivocally positive bipedal lymphangiograms were treated with extended-field radiotherapy. External beam radiation to extended pelvic portals was limited to 4500 cGy using the linear accelerator and approximately 6000 mg-hr brachytherapy. Nodal boosts up to 500 cGy were generally limited to fields measuring less than 50 cm2. Higher doses were administered in 12 patients because of poor tumor regression. Eleven of these 12 patients experienced severe complications, and only three achieved control of their tumor. The type of treatment complication appeared to be directly related to specific modifications of the initial treatment plan. Treatment failures occurred within and outside of treatment portals with equal frequency.

Carcinoma↗
PubMed1986

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↗