Radiation complications and tumor control after plaque radiotherapy of choroidal melanoma with macular involvement.

PURPOSE: To determine the outcome of plaque radiotherapy in the treatment of macular choroidal melanoma and to identify the risk factors associated with the development of radiation complications, tumor recurrence, and metastasis. METHODS: Chart analysis of 630 consecutive patients (630 eyes) with macular choroidal melanoma managed by plaque radiotherapy between July 1976 and June 1992. RESULTS: The median largest basal tumor diameter was 10 mm, and the median tumor thickness was 4 mm. By means of Kaplan-Meier estimates, visually significant maculopathy developed at 5 years in 40% of the patients, cataract in 32%, papillopathy in 13%, and tumor recurrence in 9%. Vision decrease by 3 or more Snellen lines was found in 40% of the patients at 5 years. Sixty-nine eyes (11%) were enucleated because of radiation complications and recurrence. Twelve percent of the patients developed metastasis by 5 years and 22% by 10 years. Results of multivariate Cox proportional hazards analyses showed that the significant predictors for tumor recurrence were a distance of tumor margin from the optic disk of less than 2 mm (P = .003) and retinal invasion (P = .009). The significant variables that were predictive of metastasis included tumor thickness greater than 4 mm (P = .02) and largest basal tumor diameter greater than 10 mm (P = .03). CONCLUSIONS: Plaque radiotherapy offers a 91% 5-year local tumor control rate for macular choroidal melanoma. Despite good local tumor control, the risk for metastasis is 12% at 5 years and 22% at 10 years. In 11% of the patients, enucleation eventually became necessary because of radiation complications and tumor recurrence.     

A phase II trial of bryostatin 1 in the treatment of metastatic colorectal cancer.

Current chemotherapy for patients with advanced colorectal cancer is relatively ineffective and may be associated with significant toxicity. Bryostatin 1 (bryo 1) influences cell proliferation, intracellular metabolism and signaling, differentiation, and apoptosis in human cancer cell lines via modulation of protein kinase C (PKC) activity. This trial investigates the efficacy and toxicity of bryo 1 as a novel therapeutic agent for patients with advanced colorectal cancer who have had previous 5-fluorouracil therapy. The primary end point was tumor response to bryo 1. Toxicity was also assessed. Twenty-eight patients with advanced colorectal cancer were enrolled. The mean age was 59 years (range, 38-76), with 16 men and 12 women, and good minority representation (11 African-Americans). The first 10 patients initially received 25 microg/m2 of bryo 1 weekly as a 24-h infusion for 3 weeks of every 4-week cycle, with dose escalation to 35 microg/m2 starting with the second cycle. The remaining patients were started at 35 microg/m2 and escalated to 40 microg/m2, if toxicity was minimal. Twenty-five patients were evaluable for objective tumor response, and complete data on toxicity were collected on 26 patients. No partial or complete tumor responses were observed. All 25 patients had disease progression within four cycles. Myalgia was the most common toxicity. Myelosuppression was not seen. bryo 1 as a weekly 24-h continuous infusion lacks single-agent antitumor activity in advanced colorectal cancer. Toxicity differs from that of traditional chemotherapeutic drugs.     

Oral cimetidine (Tagamet) for recalcitrant, diffuse conjunctival papillomatosis.

PURPOSE: To report the efficacy of cimetidine for treatment of conjunctival papillomatosis. METHODS: An 11-year-old boy had an 8-year history of diffuse conjunctival papillomas, treated previously with standard measures of excisional biopsy and cryotherapy. He developed spontaneous conjunctival bleeding and diffuse tumor recurrence over the entire conjunctival surface. Oral cimetidine liquid (30 mg/kg/day) was prescribed. RESULTS: Within 2 months, dramatic tumor regression was noted, with nearly complete resolution by 4 months. The patient had no local or systemic side effects from the medication. CONCLUSIONS: Oral cimetidine possesses immune modulation properties and may be useful in some cases of virus-induced conjunctival papillomatosis.     

Choroidal melanoma metastatic to the contralateral choroid

PURPOSE: To report metastasis of choroidal melanoma to the contralateral choroid. METHODS: Interventional case report. In a 49-year-old Caucasian female, a primary choroidal melanoma, left eye, was diagnosed and treated with Ruthenium-106 plaque radiotherapy. The choroidal melanoma showed excellent regression with flattening of the mass and adjacent chorioretinal atrophy. RESULTS: Fifteen years after brachytherapy for choroidal melanoma, left eye, the patient developed a metastatic melanoma to the contralateral choroid as the first sign of metastasis. No history of oculo(dermal) melanocytosis or cutaneous melanoma existed. Systemic evaluation disclosed multiple metastases confined to the liver. CONCLUSION: Metastasis to the contralateral choroid can be the first sign of metastasis from choroidal melanoma.     

The effect of stem geometry on stresses within the distal cement mantle in total hip replacement.

Cement-stem debonding is one of the most common reasons for failure in Total Hip Replacement (THR). Four similar THR prostheses design configurations were investigated with reference to the influence of mechanical stress occurring in a cement mantle of differing thicknesses and potentially affecting clinical performance. Non-linear finite element analysis was performed on constant cement mantle thicknesses of 1, 2, and 4 millimetres. The results obtained indicate stress levels within the cement mantle decrease with increasing cement mantle thickness. The prosthesis distal tip is shown to have particular significance. Truncation of the distal tip hemisphere to a flat profile for the fixation of a centralizer increases the cement stresses.     

Anticipatory control of vertical lifting force and momentum during the squat lift with expected and unexpected loads.

STUDY DESIGN: Mixed, repeated measures design. OBJECTIVES: To determine if previous experience with loads of similar weight influences the anticipatory lifting force and postural adjustments during the squat lift. To examine a multijoint, functional task for coordination between stability and movement. To determine if lifting unexpected loads results in trunk loading patterns associated with greater injury risk. BACKGROUND: Workers are increasingly exposed to variability in materials handling thereby increasing the risk of injury. Understanding the control processes underlying lifting will support clinical decision making for preparing injured workers to return to realistic working conditions. METHODS AND MEASURES: Subjects (19 men, 4 women; mean age, 25.4 +/- 3.5 y) lifted a series of boxes weighing 5%, 20%, and 35% of their maximal lifting capacity. The loads were delivered via a gravity conveyor. The identical-appearing loads were ordered so that the subjects lifted several loads of similar weight, immediately followed by a lighter or heavier than expected load based on the previous lift. RESULTS: Generally, the vertical lifting force, force rate, horizontal momentum, and angular momentum increased with an increase in expected load. Higher peak lumbar extensor moments occurred with lighter than expected loads (expected 20% and lifted 5% load = 238.2 +/- 91.2 N-m; expected 35% and lifted 5% load = 278.2 +/- 101.8 N-m) compared to expected loads of similar weight (expected and lifted 5% load = 205.0 +/- 73.2 N-m). Heavier than expected loads led to eccentric trunk movements when there were large mismatches between the expected and actual loads. CONCLUSIONS: The vertical lifting forces and whole body momentum were predictively scaled according to the expected load. The loading phase relationships indicated coordination between the lifting force, force rate, horizontal momentum, and angular momentum. Trunk loading during the lifts with unexpected loads showed patterns associated with increased injury risk.     

Varicella vaccine exposure during pregnancy: data from the first 5 years of the pregnancy registry.

OBJECTIVE: To assess the risks of congenital varicella syndrome and other birth defects in offspring of women who inadvertently received varicella vaccine during pregnancy or within 3 months of conception. METHODS: Pregnant women inadvertently exposed to varicella vaccine, reported voluntarily, were enrolled in the Pregnancy Registry for VARIVAX (Merck & Co., Inc., West Point, PA). The pregnancies were monitored and the outcomes ascertained from questionnaires completed voluntarily by the health care providers. The rates of congenital varicella syndrome and congenital anomalies were calculated for seronegative women prospectively reported to the registry. RESULTS: From March 17, 1995 through March 16, 2000, 362 pregnancy outcomes were identified from prospective reports. Ninety-two women were known to be seronegative to varicella, of whom 58 received their first dose of vaccine during the first or second trimester. No cases of congenital varicella syndrome were identified among 56 live births (rate 0%, 95% confidence interval [CI] 0, 15.6). Among all the prospective reports of live births, five congenital anomalies were reported. No specific pattern was identified in either the susceptible cohort or the sample population as a whole. CONCLUSION: No abnormal features have been reported that suggested the occurrence of congenital varicella syndrome or other birth defects related to vaccine exposure during pregnancy. Because of the small numbers, this study has limited precision, so continued surveillance is warranted. However, these results should provide some assurance to health care providers and women with inadvertent exposure before or during pregnancy.     

Gene-mediated osteogenic differentiation of stem cells by bone morphogenetic proteins-2 or -6.

Bone marrow-derived mesenchymal stem cells (BMDMSC) hold promise for targeted osteogenic differentiation and can be augmented by delivery of genes encoding bone morphogenetic proteins (BMP). The feasibility of promoting osteogenic differentiation of BMDMSC was investigated using two BMP genes in monolayer and three-dimensional alginate culture systems. Cultured BMDMSC were transduced with E1-deleted adenoviral vectors containing either human BMP2 or BMP6 coding sequence under cytomegalovirus (CMV) promoter control [17:1 multiplicities of infection (moi)] and either sustained in monolayer or suspended in 1 mL 1.2% alginate beads for 22 days. Adenovirus (Ad)-BMP-2 and Ad-BMP-6 transduction resulted in abundant BMP-2 and BMP-6 mRNA and protein expression in monolayer culture and BMP-2 protein expression in alginate cultures. Ad-BMP-2 and Ad-BMP-6 transduced BMDMSC in monolayer had earlier and robust alkaline phosphatase-positive staining and mineralization and were sustained for a longer duration with better morphology scores than untransduced or Ad-beta-galactosidase-transduced cells. Ad-BMP-2- and, to a lesser degree, Ad-BMP-6-transduced BMDMSC suspended in alginate demonstrated greater mineralization than untransduced cells. Gene expression studies at day 2 confirmed an inflammatory response to the gene delivery process with upregulation of interleukin 8 and CXCL2. Upregulation of genes consistent with response to BMP exposure and osteogenic differentiation, specifically endochondral ossification and extracellular matrix proteins, occurred in BMP-transduced cells. These data support that transduction of BMDMSC with Ad-BMP-2 or Ad-BMP-6 can accelerate osteogenic differentiation and mineralization of stem cells in culture, including in three-dimensional culture. BMP-2-transduced stem cells suspended in alginate culture may be a practical carrier system to support bone formation in vivo. BMP-6 induced a less robust cellular response than BMP-2, particularly in alginate culture.