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Biomedical subjects

M Copeland

Publications and source records attributed to M Copeland.

At least 19 recordsLinked to original sources
PubMed1999

Pigmented schwannoma of the ventral spinal cord.

Pigmented schwannomas of the spinal canal are rare entities. We present a case of such in an unusual, ventral intradural, extramedullary location in a 27-year-old man. Imaging and histopathologic findings, including electron microscopy, showed an intradural, extramedullary pigmented schwannoma, densely adherent to the leptomeninges of the anterior median septum. This lesion is demonstrative of the neuroectodermal origin of these lesions and represents a rare location of these tumors.

Adult↗
PubMed1998

Stereotactic ventriculoperitoneal shunt for idiopathic intracranial hypertension: technical note.

OBJECTIVE: Lumboperitoneal shunting is the bastion of neurosurgical management for idiopathic intracranial hypertension (IIH). However, recent studies document a high failure rate for this procedure. The present study was designed to explore the feasibility of placing ventriculoperitoneal shunts under stereotactic control into patients with IIH as an alternative to lumboperitoneal shunting. METHODS: Seven patients with IIH for whom medical management had failed underwent stereotactic implantation of ventriculoperitoneal shunts. RESULTS: Shunt placement was successful and uncomplicated in each case. Five of seven patients experienced complete resolution of papilledema. The remaining two patients showed resolving papilledema. Six of seven patients experienced resolution of headache. The remaining patient continued to have headaches despite a radionuclide study demonstrating normal shunt function. CONCLUSION: Our results suggest that stereotactic ventriculoperitoneal shunting may be a reasonable alternative to lumboperitoneal shunting in those patients with IIH who require surgical intervention.

Adult↗
PubMed1994

Tissue ablation by a free-electron laser tuned to the amide II band.

Efforts to ablate soft tissue with conventional lasers have been limited by collateral damage and by concern over potential photochemical effects. Motivated by the thermal-confinement model, past infrared investigations targeted the OH-stretch mode of water with fast pulses from lasers emitting near 3,000 nm (refs 1, 7-9). What does a free-electron laser offer for the investigation of tissue ablation? Operating at non-photochemical single-photon energies, these infrared sources can produce trains of picosecond pulses tunable to the vibrational modes of proteins, lipids and/or water. We report here that targeting free-electron laser radiation to the amide II band of proteins leads to tissue ablation characterized by minimal collateral damage while maintaining a substantial ablation rate. To account for these observations we propose a novel ablation mechanism based on compromising tissue through resonant denaturation of structural proteins.

Amides↗
PubMed1994

Breast size as a risk factor for sternal wound complications following cardiac surgery.

OBJECTIVE: To determine if macromastia is associated with risk for deep sternal wound infection following cardiac surgery via median sternotomy incision. DESIGN: Case-control study. SETTING: Private urban teaching hospital. PARTICIPANTS: Women who developed deep sternal wound infection after undergoing cardiac surgery via median sternotomy incision and a random sample of women who did not develop infection following the same surgery. OUTCOME MEASURES: Odds ratios (ORs) were used to compare the development of deep sternal wound infection in women who wore large bra cups (size D or DD) with women who wore small bra cups (size A or B) and to compare women who wore medium bra cups (size C) with those who wore small bra cups. RESULTS: For women who wore large bra cups, the OR for deep sternal wound infection was 38.5 (95% confidence interval [CI], 5.6 to 265.8) compared with women who wore small bra cups. For women who wore medium bra cups, the OR for deep sternal wound infection was 12.3 (95% CI, 2.2 to 68.7). The multivariate adjusted ORs, controlling for body mass index, internal mammary artery grafting, diabetes, and age, were 42.1 (95% CI, 3.7 to 477.3) for women who wore large bra cups compared with women who wore small bra cups and 14.9 (95% CI, 1.7 to 129.7) for women who wore medium bra cups compared with women who wore small bra cups. CONCLUSIONS: Large and medium bra cups sizes are associated with an increased risk for deep sternal wound infection after undergoing cardiac surgery via median sternotomy incision.

Aged↗
PubMed1994

Silicone breakdown and capsular synovial metaplasia in textured-wall saline breast prostheses.

Saline-filled prostheses are currently the only type of prostheses available for cosmetic use in the United States because of concerns raised about the possibility of systemic toxicity of silicone-filled artificial mammary implants. Although the approved implants are saline-filled, their potential to release silicone particles from the shells has not been systematically evaluated. We performed microscopic examination of the pericapsular tissue of 54 patients with textured-surface implants and compared these with 51 patients with smooth-walled implants over a 2-year period. The capsules that had formed around virtually all textured-surface implants had silicone fragments present either in extracellular spaces, in vacuolated histiocytes, or in the form of foreign-body granulomas in surrounding fibroadipose tissue but not in capsules associated with smooth-walled implants. In 87 percent of samples of pericapsular tissue from textured saline implants, the contact surface displayed exuberant reactive synovial metaplasia, a histologic pattern not previously described with these devices. Our findings suggest that smooth-walled prostheses are associated with less silicone fragmentation than textured devices in the peri-implant tissue capsules that tend to form around artificial surfaces used for this purpose.

Breast↗
PubMed1993

Systemic inflammatory disorder related to fibrous breast capsules after silicone implant removal.

Silicone breast implants have been associated with connective-tissue inflammatory syndromes such as systemic sclerosis, and as with other artificial breast prostheses, fibrous capsules tend to form around the implants. The capsular tissue is generally considered inert and typically is left in situ when the prostheses are explanted. We report a patient who formed symptomatic bilateral submammary cysts associated with pain, swelling, arthralgia, fever, axillary lymphadenopathy, accelerated erythrocyte sedimentation rate, and antinuclear antibody following removal of intact silicone breast implants without capsulectomy. Clinical improvement followed removal of the capsules, which histologically displayed fragments of silicone, fibrous tissue, and inflammatory cells. Our experience suggests that when silicone breast implants are thought to be the cause of a clinical inflammatory syndrome characterized by mammary pain, swelling, arthralgia, or serologic abnormalities, consideration should be given to removing the capsules entirely so that the chance of a perpetuating reaction will be reduced.

Arthritis↗
PubMed1992

Macromastia as a factor in sternal wound dehiscence following cardiac surgery: management combining chest wall reconstruction and reduction mammoplasty.

Major sternal wound infection occurs in nearly 2% of patients following coronary artery bypass graft surgery. The relationship of this complication to gender has not been reported in detail, nor has female breast size previously been implicated as a factor increasing the risk of sternotomy dehiscence. We report two cases of sternotomy wound dehiscence in women with large, pendulous breasts undergoing myocardial revascularization surgery and postulate that the weight of large, unsupported breasts produced inferolateral tension on the midline sternotomy incisions, contributing to dehiscence of the wounds. Chest wall reconstruction was accomplished using pectoralis muscle flaps, and the procedures were combined with amputative reduction of the size of the breasts, with subsequently successful healing in each case. Combining sternal reconstruction with breast reduction surgery may lead to improved secondary outcome, and postoperative use of supportive brassieres may reduce the frequency of this complication.

Aged↗
PubMed1991

Maxillary antral bone grafts for repair of orbital fractures.

Use of bone from the maxillary antrum to repair defects in the orbital floor was described more than 20 years ago but has not been reported for correction of orbital rim fractures. The method is appealing because the source is contiguous with the recipient site; enhanced exposure might allow better fracture reduction and evacuation of debris and hematoma from the maxillary sinus. The intraoral approach also avoids an external incision and scar, prevents such complications as pneumothorax or dural perforation, and reduces postoperative pain. In 60 cases of orbital and zygomatic complex fractures seen between 1985 and 1990, less than 8% required more extensive graft material than the maxillary antra could provide. To assess the potential advantages of local over extraanatomical bone grafts, we evaluated maxillary antral bone grafts obtained through buccal sulcus incisions in 14 patients for restoration following fractures of the orbit. Several of these patients are described. Bone union was complete in all patients and there was no morbidity related to infection, oroantral fistula formation, dehiscence, or disfigurement. Sufficient bone was available from the uninvolved contralateral side to repair even severely comminuted fractures. In zygomatic complex fractures, maxillary antral grafts appeared to provide additional strength in the region of the fractured maxillary buttress. The success of the procedure in our experience, coupled with the safety of bone harvesting from this source, and the avoidance of an external scar make maxillary antral bone well suited to reconstruction of all areas of the orbit.

Adult↗
PubMed1990

The effects of very early palatal repair on speech.

One hundred subjects were evaluated to investigate speech intelligibility at age 5 following very early palate repair. Evaluation was achieved using a visual analogue. The effect of articulation, nasal resonance and nasal escape on intelligibility, and other factors which may affect results, such as fistulae, otitis media, cleft types and age of repair, are discussed. Results show that 87 subjects had acceptable speech and 13 had unacceptable speech. Nine subjects had poor articulation, 9 had moderate to severe nasal escape and 7 had moderate to severe nasal resonance. Only 6 subjects required pharyngoplasty.

Age Factors↗
PubMed1988

Ganglions of the temporomandibular joint: case report and review of literature.

We present the third reported case of a ganglion cyst arising from the temporomandibular joint. Like the previous two cases, this lesion occurred in a woman over the age of 40. Unlike the lesions in previous reports, the cyst in our patient was not associated with pain or tenderness, making the diagnosis of parotid tumor more likely. Nevertheless, the case serves to illustrate the need for including ganglion in the differential diagnosis of well-encapsulated preauricular masses in the region of the temporomandibular joint.

Female↗
PubMed1984

Immunohistochemical localization of corticotropin releasing factor (CRF) in the hypothalamus of the squirrel monkey, Saimiri sciureus.

Corticotropin releasing factor immunoreactive (CRF-IR) neuronal cell bodies and fibers have been localized in both the paraventricular and supraoptic nuclei of the hypothalamus of the squirrel monkey. The major projection from these nuclei is to the median eminence and neural stem. A few CRF-IR fibers were found in the dorsal pars nervosa primarily adjacent to the pars intermedia. A rostral projection of CRF-IR fibers is associated with the suprachiasmatic nucleus and continues to septal areas. A caudally projecting bundle of fibers was observed entering the midbrain in neuropil adjacent to the aqueduct. The location of CRF-IR components is also compared with those containing vasopressin (AVP).

Animals↗
PubMed1980

The prostaglandins of articular cartilage. I. Correlates of prostaglandin activity in a chondrocyte culture system.

Suspensions of aggregated chondrocytes display active prostaglandin (PG) production. Radioimmunoassay of culture media and thin layer chromatographic analysis suggests that PGE2 is the primary PG synthesized. In order of decreasing concentration, the following PG were tentatively identified; PGE greater than PGI greater than PGA + PGB greater than or equal to PGF1+2 greater than TxB. An inverse logarithmic relationship was identified between PG synthesis and cells cultured at densities of 1.5 to 7.5 x 10(6) cells/ml. Little or no change in the PG distribution profile was seen at these high cell densities. Maximum PG synthesis was attained after 36 hours of incubation with persistence of high synthetic levels up to 48 hours. PGE2 production measured at various post-isolation intervals indicated an initial high rate of synthesis during the first 4 hours which decreased with time up to 24 hours. Cartilage explant organ cultures demonstrated a similar level of PG synthesis suggesting minimal effect of matrix on cellular PG production. Indomethacin (5 microgram/ml) inhibited PG synthesis by 70% within 4 hours and 85% after 24 hours of exposure. Arachidonic acid supplementation (10 microM) stimulated PG synthesis by 300%.

Animals↗