Correlation of Ki-67, p53, and Adnab-9 immunohistochemical staining and ploidy with clinical and histopathologic features of severely dysplastic colorectal adenomas.

Variations of Ki-67, p53, and Adnab-9 monoclonal antibody reactions in colonic adenomas may be associated with colonic cancer risk. We studied the predictive value of these markers for adverse behavior in severely dysplastic colorectal adenomas, such as an associated carcinoma, multiplicity of adenomas, and subsequent development of adenomas. For this purpose we compared theclinical, gross, and histologic characteristics of highly dysplastic index polyps in 42 patients with Ki 67, p53, and Adnab-9 immunostaining and other molecular markers.

Effect of insulin-like growth factor type I on critical size calvarial bone defects in irradiated rats.

Irradiated wounds are characterized by a slow healing process. Insulin-like growth factor-1 (IGF-1), a somatomedin C, has been shown in previous studies to stimulate collagen synthesis and bony repair. The purpose of this investigation is to evaluate the potential beneficial effects of recombinant IGF-1 in the healing of critical size calvarial defects in previously irradiated adult male Sprague-Dawley rats.

Hepatic ablation using bipolar radiofrequency electrocautery.

Rationale And Objectives: Percutaneous methods have been used to treat primary and secondary hepatic neoplasms. In the current study, we evaluated the potential of bipolar radiofrequency (RF) electrocautery to increase in vitro liver tissue destruction when compared with monopolar RF electrocautery.

Methods: Two needles (electrodes) were placed into fresh bovine liver tissue for use with bipolar electrocautery.

Prognostic significance of DNA ploidy in Ta/Tl bladder cancer: A southwest oncology group study.

While 80% of transitional cell carcinomas (TCC) present as Ta Tl lesions, they account for only 15% of deaths caused by TCC. We have evaluated the ability of DNA ploidy analysis to predict outcome in 228 patients with Ta Tl TCC. All patients were judged to be at increased risk for tumor recurrence due to having two occurrences of Stage TI tumor within 56 weeks, or three or more tumors presenting simultaneously within 16 weeks of registration.

Cranial bone grafting: biodegradable versus titanium fixation in a rabbit model.

Rigid internal fixation with miniplates and screws has enabled reconstructive surgeons to position bony segments precisely. Unfortunately, our present systems have been associated with a potential adverse effect on ultimate craniofacial growth and development. Also, they may be palpable, necessitating secondary procedures for removal of the hardware.

Polyglyconate fixation successfully stabilizes zygomatic osteotomies in a nonhuman primate.

Investigators have reported problems with metal plates and screws, including restriction of craniofacial growth necessitating secondary removal; bone resorption secondary to stress shielding; increased incidence of infection, extrusion, and palpability, especially in regions with minimal soft-tissue coverage; and interference with radiological studies and postoperative radiation therapy. Biodegradable rigid fixation can easily eliminate a majority of these problems because the material provides adequate fixation for a finite interval corresponding to bony repair. For this reason, there has been increasing interest in developing satisfactory biodegradable plate and screw systems.

Histogenesis of adenosquamous bronchogenic carcinoma.

In our hamster lung cancer model studies, among 463 non-small-cell lung cancers (NSCLC), there were 47 adenosquamous neoplasms. In 24 of 27 lesions with diameters of less than 3.0 mm, the adenocarcinoma and the squamous cell carcinoma components arose as separate, spatially discrete lesions, but these were separate in only 7 of 20 lesions with diameters of 30 mm or greater.

Biodegradable polyglyconate plates and screws: a histological evaluation in a rabbit model.

Within the zygomatic arch, bilateral osteotomies were performed on 20 adult male New Zealand white rabbits. These were stabilized in an anatomical position with polyglyconate acid plates and screws. At 3, 4, 6, 9, and 12 months, rabbits were killed and their zygomatic complexes removed en bloc.

Successful xenotransplantation of human lung cancer correlates with the metastatic phenotype.

Background: Occult micrometastases could explain deaths from stage I non-small cell lung cancer (NSCLC) after complete resections. If patients who have occult metastases could be identified, systemic therapy might be beneficial.

Methods: Non-small cell lung cancers from 81 patients in stages I, II, and III were transplanted to nude beige mice.

Effect of insulin-like growth factor type 1 on critical-size defects in diabetic rats.

A number of investigators have reported on the clinically significant relationship between diabetes mellitus and impaired wound healing. Diabetic patients have an increased frequency of infection, delayed scar formation, and poor bony union. Investigations completed in our laboratory have demonstrated that insulin-like growth factor type 1 (IGF-1), a somatomedin C, has shown promise for accelerating bony repair.

Repair of experimental calvarial defects with Bio-Oss particles and collagen sponges in a rabbit model.

Various materials have been used for reconstruction of both acquired and congenital calvarial defects. Unfortunately, each has its limitations. Autologous bone grafts have irregular rates of resorption that may require secondary corrective surgery, and individual harvest sites have limited stores that can necessitate additional donor locations.

Retrograde ejaculation due to heterotopic erectile tissue.

We report a case of retrograde ejaculation due to an unusual prostatic urethral mass. The resected tissue was histologically indistinguishable from corpus spongiosum, and due to its location it was diagnosed as heterotopic erectile tissue. The embryological origin of this lesion is discussed.

The effects of insulin-like growth factor-1 on critical-size calvarial defects in Sprague-Dawley rats.

In a previous study prepared in 1992, we found that insulin-like growth factor-1 showed promise in hastening intramembranous bone repair in midfacial bone defects. For the present study, we created critical-size calvarial defects in 36 adult male Sprague-Dawley rats. The rats were then divided into two groups and killed at 1, 2, 3, 4, 5, 6, and 8 weeks.

Effect of insulin-like growth factor-1 on zygomatic arch bone regeneration: a preliminary histological and histometric study.

A number of physicians have attempted to pharmacologically manipulate the healing of bony fractures with a variety of agents such as growth hormone, thyroxine, chondroitin sulfate, and parathyroid hormone. Thus far, results from these experiments have been inconclusive. Previous research dealing with insulin-like growth factors has centered on cultures of osteoblast-like cells and has demonstrated a stimulatory effect on bone collagen synthesis, which may in fact play a critical role in the process of bone formation itself.

Polyglyconate plates and screws to stabilize zygomatic osteotomies in a rabbit model.

Rigid internal fixation with miniplates and screws continues to be widely used in the correction of both congenital and acquired craniomaxillofacial deformities. This technique allows precise three-dimensional stabilization of bony segments. A number of recent reports have detailed some disadvantages, including potential growth restriction in developing children, bone resorption, infection, extrusion, and palpability.

Midfacial fracture repair in the adult rat.

The consensus in the literature is that fracture healing within the midface occurs via fibrous union. Clinical experience with the surgical correction of established traumatic deformities has not borne this out. An earlier histological examination with human biopsy specimens demonstrated that eventually repair occurred by direct bony union.

Reconstruction of calvarial defects with anorganic bovine bone mineral (Bio-Oss) in a rabbit model.

Reconstructive surgeons have employed various procedures using either autogenous or alloplastic materials to repair cranial defects secondary to trauma, extirpative surgery, or congenital anomalies. Currently, the choice appears to be dependent on the personal choice or background of the operating surgeon. For years, our preference has been to use calvarial bone grafts as our primary source of reconstructive material.

The effect of insulin growth factor-1 on calvarial sutures in a Sprague-Dawley rat.

Early investigations attempting to determine the exact pathogenesis of premature closure of the cranial sutures were limited by the untoward sequelae caused by surgical procedures in animal models to simulate the development of craniosynostosis. In an attempt to create a model for evaluating the effects of manipulating the craniofacial sutures without the limitations of associated scarring, we conceived an animal prototype dependent on the effects of insulin growth factor-1 on the anterior frontal suture in a Sprague-Dawley rat model. The experimental group received 2 mg of IGF-1 over a 14-day period via a subcutaneously placed osmotic infusion pump, whereas the age-matched control group received no treatment.

Hepatic ablation with use of radio-frequency electrocautery in the animal model.

The potential of percutaneous radio-frequency (RF) electrocautery hepatic ablation was evaluated in the animal model. RF hepatic ablation was performed under ultrasound (US) guidance in the liver of 10 swine with use of a specifically designed needle. The needle was placed through the liver capsule, and ablation was performed after isolating the liver at laparotomy.

Use of biodegradable plates and screws in a rabbit model.

During the last decade, rigid internal fixation with miniplates and screws has gained widespread acceptance in the correction of both congenital and acquired craniomaxillofacial deformities. Recent studies have proposed that the currently employed metallic plates and screws may require removal because of potential facial growth restriction in growing children. Others have reported bone resorption under the plate due to stress shielding, infection, extrusion, and palpability in regions where there is minimal tissue coverage.

Experimental renal embolization: preliminary results with polyacrylonitrile-based multiblock copolymers.

Preparations of polyacrylonitrile (PAN) are now being considered as possible new therapeutic embolization agents. This study evaluated two different liquid PAN formulations and a solid particle form (particle diameters, 100-400 microns). Eighteen rabbits underwent unilateral renal embolization with one of the three different preparations (n = 6 in each group).

20 year follow-up on microinvasive squamous carcinoma of the cervix.

MISC of the cervix is a potentially fatal disease if not properly classified and treated. Strict criteria for diagnosis are required to provide appropriate therapy. It is recommended that a radical approach be considered for those patients in whom the depth of invasion of the carcinoma is greater than 3 mm on cone biopsy and in all cases where vascular invasion is demonstrated.