Extended Indications for Lung Volume Reduction Surgery in Advanced Emphysema

Background. Lung volume reduction surgery has shown early promise as a palliative therapy in severe emphysema. Selection of potential candidates has been based on certain functional and anatomic criteria, and a variety of operative contraindications have been proposed.

Methods. Over 15 months, we performed lung volume reduction surgery in 85 patients selected on the basis of severe hyperinflation with air trapping, diaphragmatic dysfunction, and disease heterogeneity. Patients were not excluded on the basis of severe hypercapnia, steroid dependence, profound pulmonary dysfunction, or inability to complete preoperative rehabilitation.

Results. We observed significant improvements in pulmonary function, exercise capacity, and dyspnea, with an acceptable 30-day perioperative mortality of 7% and actuarial survival of 90% and 83% at 6 and 12 months, respectively. In each “high-risk” group, perioperative mortality, actuarial survival to 1 year, and functional results were equivalent, and in some cases superior, to those in the corresponding “low-risk” patients.

Conclusions. Severe hypercapnia, steroid dependence, profound pulmonary dysfunction, and inability to complete preoperative rehabilitation do not preclude successful lung volume reduction surgery and should not be regarded as absolute exclusionary criteria.     

Laminin-dependent and laminin-independent adhesion of human melanoma cells to sulfatides

Sulfatides (galactosylceramide-I3-sulfate) but not neutral glycolipids or gangliosides adsorbed on plastic promote adhesion of the human melanoma cell line G361. Direct adhesion of G361 cells requires densities of sulfatide greater than 1 pmol/mm2. In the presence of laminin, however, specific adhesion of G361 cells to sulfatide or seminolipid (galactosylalkylacyl-glycerol-I3-sulfate) but not to other lipids is strongly stimulated and requires only 25 fmol/mm2 of adsorbed lipid. The effects of laminin and sulfatide on adhesion are synergistic, suggesting that laminin is mediating adhesion by cross-linking receptors on the melanoma cell surface to sulfatide adsorbed on the plastic. Although thrombospondin binds to sulfatides and G361 cells, it does not enhance, but rather inhibits direct and laminin-dependent G361 cell adhesion to sulfatide. In contrast, C32 melanoma cells also adhere specifically to sulfatide, but adhesion of these cells is not enhanced by laminin or inhibited by antibodies to laminin that block laminin-dependent adhesion of G361 cells. Thrombospondin is a potent inhibitor of C32 cell adhesion to sulfatide. Fucoidan, which inhibits laminin binding to sulfatide, inhibits laminin-dependent adhesion of G361 cells by 50% at 0.2 micrograms/ml. Several other tumor cell lines also attach directly on sulfatide-coated surfaces. Laminin stimulates adhesion to sulfatide of three of the six cell lines tested. The ability of laminin to promote adhesion of tumor cells to sulfatide suggests that binding to sulfatide could participate in laminin-mediated cell-cell adhesion. Thus, many tumor cell lines can attach on sulfatide substrates using endogenous sulfatide binding proteins, and in some cells laminin but not thrombospondin can promote tumor cell adhesion to sulfatide.     

Active transport of carnitine into skeletal muscle

Skeletal muscle carnitine concentration exceeds plasma carnitine concentration. To determine whether this concentration gradient is maintained by active transport we studied rat soleus and extensor digitorum longus muscles. Observations consistent with the existence of an active transport mechanism were that the soleus accumulated carnitine linearly for 3 hours of incubation to exceed a distribution ratio of 1; the temperature coefficient for carnitine accumulation between 33 degrees C and 43 degrees C was 2.0; anaerobic incubation reduced carnitine accumulation by 30 percent; and the rate of carnitine accumulation was saturated at high substrate concentrations and competitively inhibited by gamma-butyrobetaine. The Km for carnitine of the carnitine transport mechanism of the soleus muscle was 0.259 mM and of the extensor digitorum longus muscle, 0.585 mM. The greater affinity of the soleus transport mechanism may explain the difference in carnitine transport by red and white muscle in intact animals. A defect in active transport of carnitine may be involved in the pathogenesis of some human myopathies characterized by excessive lipid storage and in diphtheritic cardiomyopathy.     

The Personalized Medicine Coalition

The concept of personalized medicine--that medical care can be tailored to the genomic and molecular profile of the individual--has repercussions that extend far beyond the technology that makes it possible. The adoption of personalized medicine will require changes in healthcare infrastructure, diagnostics and therapeutics business models, reimbursement policy from government and private payers, and a different approach to regulatory oversight. Personalized medicine will shift medical practices upstream from the reactive treatment of disease, to proactive healthcare management including screening, early treatment, and prevention, and will alter the roles of both physician and patient. It will create a greater reliance on electronic medical records and decision support systems in an industry that has a long history of resistance to information technology. Personalized medicine requires a systems approach to implementation. But in a healthcare economy that is highly decentralized and market driven, it is incumbent upon the stakeholders themselves to advocate for a consistent set of policies and legislation that pave the way for the adoption of personalized medicine. To address this need, the Personalized Medicine Coalition (PMC) was formed as a nonprofit umbrella organization of pharmaceutical, biotechnology, diagnostic, and information technology companies, healthcare providers and payers, patient advocacy groups, industry policy organizations, major academic institutions, and government agencies. The PMC provides a structure for achieving consensus positions among these stakeholders on crucial public policy issues, a role which will be vital to translating personalized medicine into widespread clinical practice. In this article, we outline the goals of the PMC, and the strategies it will take to foster communication, debate, and consensus on issues such as genetic discrimination, the reimbursement structures for pharmacogenomic drugs and diagnostics, regulation, physician training and medical school curricula, and public education.