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J A Persing

Publications and source records attributed to J A Persing.

At least 37 records · Page 2Linked to original sources
PubMed1995

A rapid in vitro assay of cellular chemomigration in an epithelial carcinoma cell line.

We have studied the chemomigration activity of an epithelial carcinoma cell line using a modified 96-well Boyden chamber apparatus consisting of upper and lower wells separated by an 8-microns pore polycarbonate filter. Cells from the malignant squamous carcinoma cell line A-431 were plated in the upper wells over a collagen IV-coated filter. In chemokinesis assays, the cells were allowed to migrate toward NIH 3T3 fibroblast-conditioned medium or control media in the lower wells for 6 hours at 37 degrees C with 10% CO2. A-431 cells preferentially migrate across the barrier toward conditioned media but not control media. Control normal keratinocytes showed no migration. A highly metastatic melanoma cell line and poorly metastatic melanoma cell line, in which chemomigration has been shown previously to correlate with metastatic potential, were used as positive and negative cellular controls. This system provides a rapidly quantifiable method by which the invasion characteristics of multiple cell lines can be studied simultaneously in a single assay using the 96-well format.

3T3 Cells↗
PubMed1995

Repair of critical size rat calvarial defects using extracellular matrix protein gels.

In this study the authors examined the capacity of gels of reconstituted basement membrane, laminin, and type I collagen to mediate repair of critical size defects in rat calvaria. Although autografts are widely used to repair bone defects caused by trauma or surgical treatment of congenital malformations, neoplasms, and infections, an adequate quantity of graft is not always available. Allogenic bone is readily available, but its use is associated with an increased incidence of nonunion, fatigue fracture, and rejection. Biologically active, purified components of basement membranes, which have been shown to promote osteogenic differentiation and angiogenesis in vitro and type I collagen (the major constituent of bone extracellular matrix) can be formed into native isotonic space-filling gels. In this study critical size calvarial defects were created in retired male Sprague-Dawley rats. Thirty-six animals were divided into seven groups. Group 1 (control) received no treatment for the defects. Group 2 animals were implanted with methylcellulose. Groups 3, 4, 5, and 6 were implanted with gels of type I collagen, reconstituted basement membrane, or laminin, respectively. The last group of three animals (Group 7) was implanted with 100 micrograms of type I collagen gels (identical to Group 3) and sacrificed at 20 weeks following a single CT scan to determine if complete healing could be obtained with this method given sufficient time. Except for rats in the type I collagen group that was evaluated by multiple computerized tomography (CT) scans biweekly from 2 to 12 weeks, bone repair was evaluated using CT at 12 weeks. Healing was quantified using three-dimensional reconstruction of CT. Following the final CT scan in each experimental group, animals were sacrificed, and a sample of tissues was evaluated by conventional histology. Animals treated with type I collagen gels showed 87.5% repair of the area of the defects at 12 weeks and 92.5% repair by 20 weeks. Increasing the gel volume 1.5 x accelerated complete repair to 3 months. Murine-reconstituted basement membrane and laminin gels induced 55.5% and 46.3% repair, respectively, at 3 months. In untreated control animals 7% repair of the area of the defects showed at 3 months. Histological analysis confirmed new bone formation in partial and completely healed defects. Bioengineered native collagen gels may have wide applicability for bone repair as an alternative bone graft material alone, in combination with autograft or marrow aspirate, or as a delivery system for osteogenic growth factors.

Animals↗
PubMed1995

Vascular lesions of the cranial base.

Vascular lesions can be classified broadly into two groups on the basis of cellular proliferation characteristics: hemangiomas and vascular malformations. Additional lesions include a heterogeneous group of vascular tumors such as those represented by hemangiopericytoma and those with a frankly malignant course. Those lesions located around the cranial base remain challenging and difficult clinical problems. The care of patients with these problems is complex; it frequently will need a full spectrum of individuals from many disciplines involved in many diverse aspects of management: medical, radiologic, anesthetic, and surgical. Fortunately, advances in science and technology have markedly expanded our capability in treating these patients and have allowed us increasing safety and ease in dealing with previously untreatable and unresectable lesions.

Brain Neoplasms↗
PubMed1995

Reconstruction of the cranial base.

The cranial base is a complex boundary between intracranial and extracranial anatomic structures. Adequate reconstruction of the basicranium depends on the location, size, and nature of the defect. A reconstructive ladder can be built on a few basic principles: coverage of vital structures, separation of the intra- and extradural spaces, procedural simplicity, and aesthetics. Individual consideration should be given to reconstruction of bone, soft tissue, dura, and cerebrospinal fluid spaces.

Adult↗
PubMed1994

Computer-generated slide graphics on a shoestring budget.

The use of computer-generated slides in weekly didactic conferences and at regional and national meetings is commonplace. Though adding a professional look, the expense of computer-generated slides can be prohibitive. We herein present a simple technique for generating color slides that captures the professional look of computer-generated slides at a fraction of the cost.

Audiovisual Aids↗
PubMed1994

Multiple recurrent benign schwannomas of deep and superficial nerves of the upper extremity: a new variant of segmental neurofibromatosis.

Benign schwannomas of the brachial plexus are uncommon tumors, first described in the late 19th century. These lesions, which are histologically benign, can generally be excised without sacrifice of neural elements. We present the first known case of multiple concurrent and recurrent benign schwannomas of the upper extremity in an individual who demonstrated no other evidence of neurofibromatosis, and we suggest that this case may represent a new subtype of type V neurofibromatosis.

Adult↗
PubMed1994

Experimental expansion of the maxillary sinus.

To assess the feasibility of "tissue" expansion as a means of midface advancement for correction of hypoplasia, expanders were placed in the left maxillary sinuses of New Zealand White rabbits. Twenty-one animals were used for the study, all of whom underwent implantation of radiopaque dental amalgam markers adjacent to cranial sutures at 9 days of age. The nonoperative control group (n = 13) underwent no further surgery. At 30 days of age, the experimental group (n = 8) underwent placement of an inflatable 1-mL Silastic tissue expander in the left maxillary sinus. After 1 week, inflation was begun in serial increments of 0.15-mL normal saline to a total volume of approximately 1.05 mL over a 2-week period. Lateral cephalometrograms were obtained at 9, 30, 60, and 90 days of age to measure growth of the craniofacial skeleton. Both groups demonstrated similar growth between 9 and 30 days of age; however, insertion and inflation of the tissue expander resulted in a statistically significant (p < 0.05) increase in posterior facial height, followed, in 30 days, by a significant increase in the length of the anterior cranial base. The remainder of the cranial base and the cranial vault grew without significant differences between the groups. This study demonstrates that changes in facial morphology can be effected in the growing skeleton through tissue expansion and provides further evidence to support the concept of an interrelated facial skeletal-basicranial-neurocranial axis.

Animals↗
PubMed1994

In the absence of periosteum, transplanted fetal and neonatal rat coronal sutures resist osseous obliteration.

Normal craniofacial development depends on expansion of the cranial vault by growth at the sutures. Inappropriate development of the sutures leads to global disruption of patterns of craniofacial growth. Tissue interactions between dura mater and suture matrix play a critical role in the phenotypic maintenance of cranial sutures. However, the function of the periosteum in this process remains under-reported and controversial. To examine the contribution of periosteum in maintaining the patency of coronal sutures, fetal and neonatal rat coronal sutures were transplanted to surgically created defects in adult rat host parietal bones. These sutures were examined for their ability to persist in the host milieu in the presence and absence of both donor and host periosteum. This study established that removal of both host and transplant periosteum, unlike removal of dura mater, did not lead to obliteration of either fetal or neonatal sutures. Thus, periosteum and dura mater are nonequivalent tissues with respect to influence on suture patency.

Animals↗
PubMed1994

Sagittal synostosis.

Sagittal synostosis comprises a spectrum of deformities caused by premature fusion of the sagittal suture. The treatment of sagittal synostosis is dependent on the age of the patient and the characteristics of the presenting deformity. Immediate correction of the scaphocephalic deformity is the goal of operative treatment. The operative procedures proposed involve whole-vault cranial reshaping, active shortening of the anteroposterior axis, and widening of the mediolateral dimension of the skull leading to a more normal, "rounded" skull shape.

Age Factors↗
PubMed1993

Frontonasal dysplasia in two successive generations.

Frontonasal dysplasia is thought to be a sporadic condition limited to the face and head. We describe a family from the Bahamas in which a mother, 2 of her children, and the mother's brother have variable manifestations of frontonasal dysplasia. The mother has extremely mild expression, but her brother and 2 sons are more severely affected. Besides polydactyly no other birth defects were noted in any other relatives. The pedigree is consistent with autosomal or X-linked dominant inheritance. A description of each patient is presented along with a discussion of the genetic counseling issues and review of the literature for other possibly familial cases of frontonasal dysplasia.

Adolescent↗
PubMed1993

Malignant peripheral nerve sheath tumors. A clinicopathologic study of 28 cases.

BACKGROUND: In order to improve management, the files and tissue sections of 28 cases of malignant peripheral nerve sheath tumors (MPNST) diagnosed at the University of Virginia Health Sciences Center between 1960 and 1990 were reviewed. METHODS: Clinical data tabulated included age, sex, race, the presence or absence of von Recklinghausen neurofibromatosis type 1 (NF-1), tumor size, tumor location, type of treatment, and status of surgical margins. Pathologic study included assessment of mitotic rate, divergent differentiation, cellular atypia, necrosis, and vascular reaction. RESULTS: The median disease-free survival time was 11 months, and the median overall survival time was 44 months. Overall survival and disease-free survival were significantly influenced by patient age, tumor location, tumor size, extent of surgery, and quality of margins. Patients with a family history of neurofibromatosis also had better disease-free survival. None of the other clinical variables correlated with survival. CONCLUSIONS: The authors recommended that patients with NF-1 be followed closely for MPNST development. For most cases, treatment should include aggressive surgery with wide surgical margins combined with adjuvant radiation therapy. Chemotherapy may have a role for treatment failures.

Adolescent↗
PubMed1993

Tissue interactions with underlying dura mater inhibit osseous obliteration of developing cranial sutures.

Cranial sutures play a critical role in calvarial morphogenesis, serving as growth centers during skull development. Both biomechanical tensile forces originating in the cranial base and biochemical factors present in dura mater have been postulated as determinants of suture morphogenesis and patency. A rat transplant model free of the putative biomechanical influence of the dura and cranial base was used to investigate the role of the dura mater in both the initial morphogenesis and maintenance of sutures during skull growth. Day 19 fetal presumptive (F19) and day 1 neonatal differentiated (N1) coronal sutures, including associated frontal and parietal bones, were transplanted with or without underlying dura mater to the center of adult parietal bones. After 1, 2, and 3 weeks, transplanted tissues were examined histologically and histomorphometrically to determine whether sutures formed and whether they were obliterated by ossification in the absence of dura mater. Both F19 and N1 sutures remained patent for 2 weeks either in the presence or the absence of transplant dura mater. However, at 3 weeks, in the absence of transplant dura mater, sutures were obliterated by bone, while in the presence of dura mater sutures resisted ossification, demonstrating an essential requirement for interactions with the transplant dura mater in maintaining functional sutures. Both F19 and N1 transplants showed comparable bone growth (cross-sectional surface area), regardless of the presence of transplant dura mater. These experiments suggest that tissue interactions of a biochemical nature, rather than biomechanical forces generated through the cranial base, are required to maintain the suture as a non-ossified growth center. Furthermore, while the presence of dura mater was essential for maintenance of suture patency, fetal dura mater was not required for initial suture formation.

Animals↗
PubMed1993

Calvarial deformity regeneration following subtotal craniectomy for craniosynostosis: a case report and theoretical implications.

We describe an infant with combined sagittal and unilateral coronal synostosis who underwent "total vault" craniectomy for skull reshaping. The operative procedure was interrupted without replacement of the calvarial bone grafts. Follow-up over the ensuing 2 months revealed regeneration of the entire cranium and supraorbital rims, as well as (in contrast to earlier reports) redevelopment of fusion within the suture at the same site noted in the initial operation, associated with similar skull deformity. These observations are reviewed with special emphasis on the theoretical implications for the etiology of craniosynostosis and skull deformity.

Bone Regeneration↗
PubMed1992

Neurological deterioration after lumbar cerebrospinal fluid drainage.

Large-bore lumbar spinal fluid drainage is used frequently as part of the preoperative and intraoperative management of patients undergoing cranial base tumor resection. Such drainage allows displacement of the brain with minimal force, thereby potentially decreasing retraction damage to it. We document 2 patients in whom serious complications resulted from lumbar drainage systems. These patients deteriorated into a coma state following cerebrospinal fluid (CSF) drainage. Reinfusion of synthetic CSF solutions caused a brisk return to normal neurological status. These plus other potential complications associated with lumbar drainage, such as persistent CSF leaks into the back and soft-tissue nerve root injury, warranted abandoning the lumbar cistern drainage route of CSF drainage in favor of drainage directly from the intracranial compartment. Depending on the particular operation performed, drainage of CSF near the cribriform plate, the suprachiasmatic cistern, or from the sylvian fissure may be effective sites for CSF drainage. Unlike lumbar drainage, intracranial CSF drainage does not have the added risk of promoting cerebral herniation.

Carcinoma, Squamous Cell↗
PubMed1992

The serratus anterior free tissue transfer for craniofacial reconstruction.

The serratus anterior muscle was used as a free tissue transfer to reconstruct complex craniofacial defects in 5 patients. Serratus anterior muscle alone and serratus anterior muscle with rib were the transfers made. All flaps survived and scapular winging did not occur. The serratus anterior muscle has several advantages for the reconstruction of medium-sized craniofacial defects. Because of its position, a two-team approach is possible. It has a consistent pedicle anatomy and low donor site morbidity. It has a large caliber vessel and a long pedicle. When compared with the commonly employed rectus abdominis flap for moderate-sized defects, the serratus muscle offers greater versatility in design and has the option of incorporating bone and innervated muscle without increasing significant donor site morbidity.

Adolescent↗