Combined coronary surgery and aortic valve replacement after previous right pneumonectomy

Cardiac surgery in patients with previous pneumonectomy is infrequently reported. We report a case of combined coronary artery bypass grafting and aortic valve replacement in a patient with left ventricular ejection fraction less then 35% and a previous right pneumonectomy. All steps in operative management of this rare condition are discussed.     

Viral delivery of P450 reductase recapitulates the ability of constitutive overexpression of reductase enzymes to potentiate the activity of mitomycin C in human breast cancer xenografts

Indolequinones such as mitomycin C (MMC) require enzymatic bioreduction to yield cytotoxic moieties. An attractive approach to overcome the potential variability in reductive bioactivation between tumors is to exploit specific enzyme-bioreductive drug combinations in an enzyme-directed gene therapy (GDEPT) approach. To this end, human breast cancer cell lines (T47D, MDA468, and MDA231) that overexpress either DT-diaphorase (DTD) or NADPH:cytochrome P450 reductase (P450R) have been developed. Cytotoxicity of MMC was evaluated in the panel of cell lines following aerobic or anoxic exposure in vitro. DTD and/or P450R overexpression sensitized cells to MMC in air with no further increase in the cytotoxicity of MMC under anoxia. The most profound effect was seen in the MDA468 cells, where a 27-fold increase in potency was observed for MMC in the DTD-overexpressing cell line. The MMC sensitization achieved through DTD and P450R overexpression in MDA468 cells was maintained in vivo. Xenografts established from the clonal lines exhibited significant tumor control following MMC treatment (treated/control [T/C] 17% and 51% for DTD and P450R xenografts, respectively) that was not seen in wild-type tumors (T/C 102%). Delivery of a clinically relevant adenoviral vector encoding P450R to MDA468 wild-type tumors yielded comparable P450R activity to that seen in the P450R clonal xenografts and resulted in greater MMC sensitization (T/C 46%). The model systems developed will facilitate the identification of novel indolequinone agents that are targeted toward a specific enzyme for bioactivation and are consequently of potential use in a GDEPT approach.     

Use of cardiovascular medications in the elderly

Cardiovascular disease is the leading cause of death in patients aged 65 and above. Although elderly persons represent only 12.4% of the US population, they account for about a third of drug expenditures. However the appropriate use of cardiovascular medications in these patients has been shown to reduce the rate of cardiovascular morbidity and mortality. The normal aging and the disease process in the elderly result in significant changes at the structural and molecular level in the elderly. The changes that take place in the autonomic nervous system, the kidneys, and the liver in the elderly modify the metabolism and clinical effects of most medications. Elderly patients are also susceptible to side effects and adverse drug reactions. Physicians should have a clear understanding of the normal aging processes, the abnormal changes due to disease process and the changes in the pharmacology of drugs in the elderly to deliver proper care to the elderly patient.     

Fractured Inferior Vena Cava Filter Strut Presenting with ST-Segment Elevation and Cardiac Tamponade

The fracture of an inferior vena cava filter strut and its migration to the heart is a rare sequela of implanted inferior vena cava filters. Perforation through the right ventricle into the pericardium with resultant cardiopulmonary compromise is even less frequent. We report the case of a 53-year-old man who presented with chest pain and hypotension consequent to cardiac tamponade. A fractured inferior vena cava filter strut had migrated and perforated his right ventricle. The fractured strut was successfully removed by means of cardiac surgery. Inferior vena cava filters should be placed when necessary to minimize the risk of pulmonary embolism, and regular radiologic monitoring should be performed; however, the eventual extraction of retrievable filters should be considered. In addition to discussing the patient''s case, we briefly review the relevant medical literature.     

The Fate of Transcaval Access Tracts: 12-Month Results of the Prospective NHLBI Transcaval Transcatheter Aortic Valve Replacement Study

Objectives

The authors investigated 1-year outcomes after transcaval access and closure for transcatheter aortic valve replacement (TAVR), using commercially available nitinol cardiac occluders off-label.

Marginal and internal fit of pressed lithium disilicate inlays fabricated with milling, 3D printing,and conventional technologies

Statement of problem

The subtractive and additive computer-aided design and computer-aided manufacturing (CAD-CAM) of lithium disilicate partial coverage restorations is poorly documented.

Promoting the purchase of low-calorie foods from school vending machines: a cluster-randomized controlled study

BACKGROUND: Vending machines account for food sales and revenue in schools. We examined 3 strategies for promoting the sale of lower‐calorie food products from vending machines in high schools in the Netherlands. METHODS: A school‐based randomized controlled trial was conducted in 13 experimental schools and 15 control schools. Three strategies were tested within each experimental school: increasing the availability of lower‐calorie products in vending machines, labeling products, and reducing the price of lower‐calorie products. The experimental schools introduced the strategies in 3 consecutive phases, with phase 3 incorporating all 3 strategies. The control schools remained the same. The sales volumes from the vending machines were registered. Products were grouped into (1) extra foods containing empty calories, for example, candies and potato chips, (2) nutrient‐rich basic foods, and (3) beverages. They were also divided into favorable, moderately unfavorable, and unfavorable products. RESULTS: Total sales volumes for experimental and control schools did not differ significantly for the extra and beverage products. Proportionally, the higher availability of lower‐calorie extra products in the experimental schools led to higher sales of moderately unfavorable extra products than in the control schools, and to higher sales of favorable extra products in experimental schools where students have to stay during breaks. Together, availability, labeling, and price reduction raised the proportional sales of favorable beverages. CONCLUSION: Results indicate that when the availability of lower‐calorie foods is increased and is also combined with labeling and reduced prices, students make healthier choices without buying more or fewer products from school vending machines. Changes to school vending machines help to create a healthy school environment.     

Maternal occupational exposure to polycyclic aromatic hydrocarbons: effects on gastroschisis among offspring in the National Birth Defects Prevention Study

Background: Exposure to polycyclic aromatic hydrocarbons (PAHs) occurs in many occupational settings. There is evidence in animal models that maternal exposure to PAHs during pregnancy is associated with gastroschisis in offspring; however, to our knowledge, no human studies examining this association have been conducted.Objective: Our goal was to conduct a case–control study assessing the association between estimated maternal occupational exposure to PAHs and gastroschisis in offspring.Methods: Data from gastroschisis cases and control infants were obtained from the population-based National Birth Defects Prevention Study for the period 1997–2002. Exposure to PAHs was assigned by industrial hygienist consensus, based on self-reported maternal occupational histories from 1 month before conception through the third month of pregnancy. Logistic regression was used to determine the association between estimated occupational PAH exposure and gastroschisis among children whose mothers were employed for at least 1 month during the month before conception through the third month of pregnancy.Results: The prevalence of estimated occupational PAH exposure was 9.0% in case mothers (27 of 299) and 3.6% in control mothers (107 of 2,993). Logistic regression analyses indicated a significant association between occupational PAHs and gastroschisis among mothers ≥ 20 years of age [odds ratio (OR) = 2.53; 95% confidence interval (CI): 1.27, 5.04] after adjusting for maternal body mass index, education, gestational diabetes, and smoking. This association was not seen in mothers < 20 years (OR = 1.14; 95% CI: 0.55, 2.33), which is notable because although young maternal age is the strongest known risk factor for gastroschisis, most cases are born to mothers ≥ 20 years.Conclusion: Our findings indicate an association between occupational exposure to PAHs among mothers who are ≥ 20 years and gastroschisis. These results contribute to a body of evidence that PAHs may be teratogenic.