Local hindlimb antioxidant infusion does not affect muscle glucose uptake during in situ contractions in rat.

There is evidence that reactive oxygen species (ROS) contribute to the regulation of skeletal muscle glucose uptake during highly fatiguing ex vivo contraction conditions via AMP-activated protein kinase (AMPK). In this study we investigated the role of ROS in the regulation of glucose uptake and AMPK signaling during low-moderate intensity in situ hindlimb muscle contractions in rats, which is a more physiological protocol and preparation. Male hooded Wistar rats were anesthetized, and then N-acetylcysteine (NAC) was infused into the epigastric artery (125 mg.kg(-1).h(-1)) of one hindlimb (contracted leg) for 15 min before this leg was electrically stimulated (0.1-ms impulse at 2 Hz and 35 V) to contract at a low-moderate intensity for 15 min. The contralateral leg did not receive stimulation or local NAC infusion (rest leg). NAC infusion increased (P<0.05) plasma cysteine and cystine (by approximately 360- and 1.4-fold, respectively) and muscle cysteine (by 1.5-fold, P=0.001). Although contraction did not significantly alter muscle tyrosine nitration, reduced (GSH) or oxidized glutathione (GSSG) content, S-glutathionylation of protein bands at approximately 250 and 150 kDa was increased (P<0.05) approximately 1.7-fold by contraction, and this increase was prevented by NAC. Contraction increased (P<0.05) skeletal muscle glucose uptake 20-fold, AMPK phosphorylation 6-fold, ACCbeta phosphorylation 10-fold, and p38 MAPK phosphorylation 60-fold, and the muscle fatigued by approximately 30% during contraction and NAC infusion had no significant effect on any of these responses. This was despite NAC preventing increases in S-glutathionylation with contraction. In conclusion, unlike during highly fatiguing ex vivo contractions, local NAC infusion during in situ low-moderate intensity hindlimb contractions in rats, a more physiological preparation, does not attenuate increases in skeletal muscle glucose uptake or AMPK signaling.

Graves ophthalmopathy.

Graves ophthalmopathy (GO) is an autoimmune disease that typically affects the thyroid gland and the orbit. The roles of the thyroid stimulating hormone receptor and cellular and humoral immunity in the pathogenesis of GO are being investigated. Investigators are gaining insights into the epidemiology of GO as it relates to other ocular and autoimmune diseases. Several possible tools for assessing GO disease activity are being studied. Medical and radiation therapy for GO recently have been evaluated prospectively. Orbital surgeons continue to refine orbital decompression techniques to improve patient outcomes and minimize surgical complications.

Radiation-induced meningiomas involving the orbit.

PURPOSE: To review the clinical features and outcomes of patients with radiation-induced meningiomas involving the orbit. DESIGN: Retrospective case series. PARTICIPANTS: Eight patients with radiation-induced meningiomas affecting the orbit. METHODS: Clinical and pathologic data of the patients were reviewed. MAIN OUTCOME MEASURES: Age at diagnosis, mean interval between radiation therapy and meningioma diagnosis, tumor recurrence, histologic atypia, and mean follow-up time after initial diagnosis. RESULTS: The mean age at diagnosis was 42 years (range, 21 years to 70 years). The mean interval between radiation therapy and meningioma diagnosis was 26 years (range, 3 years to 54 years). All patients underwent gross total resection or subtotal resection of the meningioma. Five tumors (62.5%) recurred, based on clinical findings and CT imaging. The mean interval between resection of the meningioma and recurrence was 3 years (range, 9 months to 9 years). Three patients (37.5%) had atypical meningiomas. One patient (12.5%) had multiple tumors. The mean follow-up interval was 7 years after initial diagnosis of the meningioma (range, 15 months to 19 years). CONCLUSIONS: This series of radiation-induced meningiomas, the first in the ophthalmic literature, illustrates the aggressive nature of this tumor.

Adrenocortical carcinoma metastatic to the orbit.

PURPOSE: To describe the clinical course and histopathologic features of a patient with adrenocortical carcinoma metastatic to the orbit. METHODS: Case report and literature review. RESULTS: A 24-year-old man first came to medical attention because of symptoms referable to a 4.47-kg, nonfunctioning carcinoma of the left adrenal cortex. Several metastases ensued, including a large tumor to the right superior lateral bony orbit with extension to the brain, temporalis fossa, and orbit proper. The tumor was resected with the use of a combined neurosurgical, ophthalmic, and craniofacial approach. The patient died of widespread metastatic disease 15 months after the orbital operation. CONCLUSIONS: Metastasis to the orbit from adrenocortical carcinoma is rare. Surgical resection is the treatment of choice, with adjunctive radiation therapy and chemotherapy in some cases. The prognosis is poor.

Surgical correction of blepharoptosis in patients with myasthenia gravis.

PURPOSE: To describe the results of surgical correction of blepharoptosis in a series of patients with myasthenia gravis (MG). METHODS: In this retrospective case series, we reviewed the medical records of all patients with MG who did not respond to medical therapy and underwent surgical correction for blepharoptosis at the Mayo Clinic between 1985 and 1999. The primary outcome measure was change in interpalpebral eyelid fissure height. RESULTS: Sixteen blepharoptosis procedures were performed on 10 patients with MG. Eight of the 10 patients had ocular MG. Two of the 10 patients had systemic MG. Of the 16 procedures performed, 9 were external levator advancements (ELA), six were frontalis slings, and one was a tarsomyectomy. Patients were followed postoperatively for an average of 34 months (range, 14-126 months). The amount of ptosis was quantified pre- and postoperatively for seven of the nine eyelids that underwent ELA. For these seven eyelids (five patients), there was a statistically significant improvement in the mean interpalpebral eyelid fissure height from 3.7 mm preoperatively to 7.8 mm postoperatively, with a mean difference of 4.1 mm (95% confidence interval 1.9 mm to 6.25 mm, p = 0.0038). Postoperative complications included worsened diplopia in one patient with ELA and exposure keratopathy in one patient with frontalis sling. Two of the ELA eyelids developed recurrent ptosis requiring additional surgery more than 2 years after the initial procedure. CONCLUSIONS: Blepharoptosis surgery can achieve eyelid elevation in patients who have failed to respond to medical therapy for MG. Potential complications include worsened diplopia and exposure keratopathy.

Surgical correction of blepharoptosis in patients with myasthenia gravis.

PURPOSE: To describe the results of surgical correction of blepharoptosis in a series of patients with myasthenia gravis. METHODS: We reviewed the medical records of all patients with myasthenia gravis who underwent surgical correction for blepharoptosis at the Mayo Clinic between 1985 and 1999. The primary outcome measure was change in interpalpebral eyelid fissure height. RESULTS: Eighteen blepharoptosis procedures were performed on 11 patients with myasthenia gravis. Eight of the 11 patients had ocular myasthenia gravis, and 3 had systemic myasthenia gravis. Of the 18 procedures performed, 11 were external levator advancements (ELA), 6 were frontalis slings, and 1 was a tarsomyectomy. Patients were followed up postoperatively for an average of 34 months (range, 9 to 126 months). The amount of ptosis was quantified preoperatively and postoperatively for 9 of the 11 eyelids that underwent ELA. For these eyelids, there was a statistically significant improvement in the mean interpalpebral eyelid fissure height, from 4.2 mm preoperatively to 8.1 mm postoperatively, with a mean difference of 3.9 mm (95% confidence interval, 2.3 to 5.5 mm; P = .0005). Postoperative complications included worsened diplopia in 1 patient who underwent ELA and exposure keratopathy in 1 patient who underwent a frontalis sling procedure. Two of the eyelids that underwent ELA developed recurrent ptosis, requiring additional surgery more than 2 years after the initial procedure. CONCLUSION: Surgical correction of blepharoptosis is an appropriate treatment option in patients with myasthenia gravis who fail medical therapy. Potential complications include worsened diplopia and exposure keratopathy.

Transcatheter uterine artery embolisation to treat large uterine fibroids.

Bilateral uterine artery embolisation was performed to treat eight women with symptomatic large fibroids requiring treatment. Uterine volume was quantitatively assessed by magnetic resonance imaging. Both uterine arteries were occluded effectively in all women, and the procedure was well tolerated, with a 24-36 hour admission for pain relief. The level of pain experienced was variable, but well controlled. Some women experienced intermittent vaginal discharge and pain following the procedure. Improvement of symptoms occurred in six of the seven women and the eighth woman conceived. There were no significant complications. At three months four women had a uterine volume of < 350 cm3. Embolisation appears to be a good alternative to surgery, but longer follow up is required to evaluate the long term effects and to determine those patients for whom the procedure is suitable.

BK virus.

BK virus is a human polyoma virus that infects the renal epithelium and remains latent until immunosuppression triggers reactivation. After reactivation, BK virus can be detected in the urine by methods currently available in the clinical laboratory. Correlations can be made between BK viruria and the occurrence of both renal and hepatic pathologies. BK virus is emerging as a significant pathogen in transplant patients. Additionally, the presence of BK virus DNA in primary brain and pancreatic tumors suggests that it may have oncogenic potential. Thus far, attempts to treat BK virus infection have been ineffective, though research has opened new avenues for treatment possibilities. Prevention of BK virus and other latent viral reactivation remains a challenge to viral research.