Nuclear magnetic resonance imaging of the heart. Current status and future prospects

The basic principles and current status of proton nuclear magnetic resonance imaging are outlined. Nuclear magnetic resonance images of the heart have improved in quality with advances in technique and better gating but clinical experience remains very limited. Myocardial infarction has been shown in animals and man, and plaques of atheroma have been seen with nuclear magnetic resonance flow studies. Further improvements in image quality, faster examination times, 23Na imaging, and the use of paramagnetic contrast agents are advances that are anticipated in the near future.     

Use of the left internal jugular vein approach in endomyocardial biopsy

Endomyocardial biopsy is conventionally performed by accessing the right internal jugular vein. The alternative approach is via the femoral veins. We describe the safe and effective use of the left internal jugular vein with a standard Caves-Schulz bioptome. © 1994 Wiley-Liss,Inc..     

Combined cytosine deaminase expression, 5-fluorocytoiine exposure, and radiotherapy increases cytotoxicity to cholangiocarcinoma cells

Cholangiocarcinoma is a malignancy that is resistant to current therapy. We applied the toxin gene therapy strategy of cytosine deaminase conversion of the nontoxic prodrug 5-fluorocytosine to 5-fluorouracil combined with radiotherapy to cholangiocarcinoma. The transduction efficiency of SK-ChA-1 cholangiocarcinoma cells was determined by fluorescence-activated cell-sorting analysis following infection with recombinant adenovirus AdCMVLacZ, which encodes the gene for β-galactosidase. To evaluate cytosine deaminase-mediated conversion of 5-fluorocytosine to 5-fluorouracil and subsequent cytotoxicity, SK-ChA-1 cells were infected with the recombinant adenovirus AdCMSXD, which encodes cytosine deaminase, and exposed to S-fluorocytosine for 6 to 8 days. Additive cytotoxicity of radiation therapy was evaluated by cobalt-60 exposure following AdCMVVCD infection and S-fluorocytosine treatment. SK-Cl&l cells were transduced (98.4%) by AdCMVLacZ at 100 plaque-forming units per cell. Following infection with AdCMIVCD and exposure to 5 to 100 μ,g/ml of 5-fluorocytosine, 20% to 64% of SK-&A-l cells were killed. A combination of radiation and cytosine deaminase/5-fluorocytosine therapy resulted in enhanced cell killing (83.5% to 91.5%). Cholangiocarcinoma cells were transduced by recombinant adenoviral vectors and were killed by cytosine deaminase-mediated production of 5-fluorouracil. Enhanced cytotoxicity was seen with the addition of external beam radiation. These results provide a foundation for multimodality therapy for human cholangiocarcinoma that combines gene therapy technology with radiation therapy. Supported by award 633602 from the Robert Wood Johnson Foundation. Presented at the Thirty-Eighth Annual Meeting of The Society for Surgery of the Alimentary Tract, Washington, D.C., May 11–14, 1997.     

An ultrastructural analysis of an oocyte from an in vitro fertilization patient with repeated polyspermic fertilization

Objective: Our goal was to determine any ultrastructural anomalies in an oocyte from a patient with a history of polyspermy. Results: Ultrastructural observations of the cortical ooplasm of several oocytes from each of three control patients showed a large population of intact cortical granules. Conversely, one oocyte from a patient with repeated polyspermic fertilization contained a relative paucity of granules in the cortex. Quantitative analysis of the cortices of control oocytes indicated that there were 17.02±0.52 cortical granules present per measured field of view, compared with 4.40±2.92 granules per field in the other oocyte. Conclusions: The presence of sufficient cortical granules is necessary for normal (monospermic) fertilization to occur. When contrasted to the cortical granule population of oocytes from several control patients, the cortex of one oocyte from the other patient showed few of these organelles. Therefore, the absence of a sufficient number of granules may have precluded normal fertilization from occurring in the eggs of this patient.     

Tumor necrosis factor and chemotherapeutic agents. Potentiation of cytotoxicity with interferon gamma.

This study examined combinations of the recombinant human cytokines, tumor necrosis factor alpha and interferon gamma, with doxorubicin and dactinomycin as well as other drugs on six squamous cell carcinoma cell lines of head and neck origin using the 3(4,5-dimethylthiazol-2-yl)2,5-diphenyl-tetrazolium bromide proliferation assay. Interferon gamma significantly enhanced the cytotoxicity of tumor necrosis factor alpha with dactinomycin on all six cell lines investigated, while in four of six cell lines the cytotoxicity of tumor necrosis factor alpha with doxorubicin was significantly augmented by interferon gamma. Additional experiments showed no effect with either cytokine in combination with cisplatin, fluorouracil, methotrexate, or etoposide. These data demonstrate that human recombinant cytokines in concert with certain drugs improve in vitro cytotoxicity and may have a potential for improving in vivo therapy.     

Circadian rhythms and coronary artery disease

Circadian variations have long been observed in several metabolic functions, many of which are directly or indirectly related to the cardiovascular system and its pathophysiology. Recent reports linking circadian patterns to the development of symptomatic and asymptomatic myocardial ischemia, sudden cardiac death and myocardial infarction raise important questions concerning the mechanisms of myocardial ischemic activity in patients with coronary artery disease, and they have implications for prognosis, therapy and further research.     

Lung cancer mortality among women employed in high-risk industries and occupations in Harris County, Texas, 1977-1980

Lung cancer is rapidly becoming the leading cause of cancer mortality among women. Interviews conducted with 259 women with lung cancer and 278 women without lung cancer or with their next-of-kin in Harris County, Texas from July 1, 1977 to June 30, 1980 revealed that 12 (4.6%) of the women with lung cancer had never smoked cigarettes. The odds ratio (OR) for current smoking was 15.7. Odds ratios for smoking for living women (OR = 17.5) were higher than for those who were deceased (OR = 12.6). Lifetime occupational histories were classified a priori into high- and low-risk categories. Data were stratified according to employment in a high-risk industry or occupation, a high-risk industry, a high-risk occupation, or both a high-risk industry and occupation. Although not statistically significant, odds ratios for employment in high-risk categories support earlier estimates that attributed 5% of lung cancer mortality in women to employment in hazardous occupations. Employment of a husband or household member in selected industries and occupations yielded significantly increased odds ratios. More cases (15.9%) than controls (6.9%) reported a family history of lung cancer (OR = 2.4). No significant increase in smoking-adjusted odds ratios was found for the use of hair spray, hand-held dryers, or alcohol, or for having lived with a household member who smoked cigarettes.     

Successful operative management of struma cordis obstructing the left ventricular outflow tract

Struma cordis, ectopic thyroid tissue located in the heart, is extremely rare. To our knowledge, this is the first report of struma cordis obstructing the left ventricular outflow tract. The tumor was removed successfully using cardiopulmonary bypass.