Organ-preference of metastasis

Summary The initial, site-specific colonization of secondary organs by blood-borne cancer cells appears to be mediated by endothelial cell adhesion molecules. These molecules are part of the organ-specific microvascular phenotype and are regulated through complex interactions of the endothelium with the extracellular matrix (e.g., distinct matrix macromolecules and growth factors). They are inducedin vitro by growing unspecific (large vessel) endothelial cells on extracts of organ-specific biomatrices. In many respects, these molecules are similar to the various classes of chemically different adhesion molecules that regulate lymphocyte traffic, but are believed to be distinct from the inducible adhesion molecules that govern leukocyte adhesion during acute episodes of inflammation. Biochemical and biophysical data indicate that preference of tumor cell adhesion to organ-specific microvascular endothelium may not require qualitative differences of such homing receptors between endothelia, but may be explained on the basis of quantitative receptor differences as well as differences of receptor avidity. Following adhesion, the metastatic cascade proceeds by the establishment of metabolic conduits between the endothelium and adherent tumor cells. This heterotypic coupling represents an early step in the extravasation of cancer cells from the microvasculature, initiating endothelial cell retraction from its basement membrane and recanalization around the arrested tumor cell. These events, together with local growth promoting effects exerted by the metastasized organ, are believed to provide the basis for Paget's seed and soil hypothesis of metastasis.     

Ends and means in public health policy in developing countries

International discussions of public health policy strategies in developing countries have been characterized by strong and conflicting positions. Differences regarding the means of health sector improvement can often be traced to differences about the ends, that is, the goals of the health sector. Three types of health sector goals are reviewed: health status improvement, equity and poverty alleviation, and individual welfare (utility) improvement. The paper argues that all three must be considered in developing health sector reform strategies in all countries. Highly normative policy positions often can be attributed a unidimensional affiliation with one health sector goal and denial of the relevance of the others. The current global interest in using cost-effectiveness analysis to set national health priorities is assessed in light of this eclectic approach. Examples are provided of how a health sector strategy based on cost-effectiveness would give sub-optimal solutions. These examples include situations where a private health care sector exists and provides some degree of substitution for publicly provided services; significantly high income elasticities exist for health care such that higher income beneficiaries may differentially capture public subsidies; and market failures exist in insurance. It is argued that these conditions are virtually universal in developing countries. Thus, rational policy development should explicitly consider multiple goals for the health sector.     

Impfentwicklungsland Deutschland? Ärzte- und Patientenbefragungen zum Thema Impfen gelangen zu widersprüchlichen Ergebnissen

Zusammenfassung Praktische ?rzte und Internisten empfinden die Impfsituation in Deutschland zum Gro?teil als unbefriedigend. Obwohl sie sich selbst die wichtigste Rolle beim Impfen zuschreiben, sehen sie die Ursachen für die niedrigen Impfzahlen vor allem in der Unwissenheit bei den Patienten, in der Angst vor der Spritze und in mangelhafter Compliance und Kontrolle. Um zu einem verbesserten Impfverhalten zu kommen, setzen die ?rzte vorwiegend auf positive Informationen in den Medien, aber auch auf die Kontrolle durch Beh?rden und Krankenkassen sowie die bessere Integration des Impfens in die Praxisorganisation. So lauten im Kern die Ergebnisse einer Untersuchung, die das Marktforschungsinstitut „Resultate” in Neu-Isenburg im Auftrag des Impfstoffherstellers Chiron Behring durchgeführt hat. Im Vergleich zu den Daten einer repr?sentativen Patientenumfrage von 1995 lassen sich übereinstimmungen finden: Tats?chlich sind die meisten Patienten schlecht informiert, insbesondere über die Notwendigkeit von Auffrischimpfungen. Ein Drittel der Befragten besitzt keinen Impfausweis, wodurch die Kontrolle erschwert wird. Im Gegensatz zu den Annahmen der ?rzte existiert jedoch eine hohe Impfbereitschaft, w?hrend Angst kaum ein Impfhindernis darstellt. Für die überwiegende Mehrheit der Patienten ist der Arzt der erste Ansprechpartner bei Impffragen.      

Simultaneous irradiation and imaging of blood vessels during pulsed laser delivery

BACKGROUND AND OBJECTIVE: Simultaneous irradiation and viewing of 10-120 microm cutaneous blood vessels were performed to investigate the effects of 2-micros 577-nm dye laser pulses. STUDY DESIGN/MATERIALS AND METHODS: A modified scanning laser confocal microscope recorded vessel response to different radiant exposures (J/cm2). Probit analysis determined the 50% probability ("threshold") radiant exposure necessary to cause embolized or partly occluding coagula, coagula causing complete blood flow stoppage, and hemorrhage. RESULTS: A statistically significant difference in the threshold radiant exposure existed for each damage category for blood vessels 10-30 microm in diameter, but not for larger vessels. For vessels over 60 microm, complete flow stoppage was unattainable; increasing laser pulse energy produced hemorrhage. In larger vessels, coagula often were attached to the superficial vessel wall while blood flowed underneath. Monte Carlo optical and finite difference thermal modeling confirmed experimental results. CONCLUSION: These results provide insight into the role of pulse duration and vessel diameter in the outcome of pulsed dye laser irradiation.     

Mono- and Diterpenes from Cell Cultures of Thuja occidentalis

Cell cultures of THUJA OCCIDENTIALIS L. were found to biosynthesize various mono- and diterpenes when grown on B5-medium. The identification of the constituents was achieved mainly by capillary GLC-MS using fused silica columns and E.I.-mass spectrometry. Monoterpenes of the menthane type were only isolated from the culture medium whereas diterpenes were found in the cell extracts. Thujaplicin derivatives, monoterpenes of an irregular type, were detected in the medium as well as in the cells. Major differences were found between the terpene composition of the cell culture extracts and those from THUJA leaves. The cell cultures accumulated some compounds which are presently unknown as constituents of THUJA plants. On the other hand, the cultures were evidently unable to synthesize the thujone type of monoterpenes.     

Stable weight during lamotrigine therapy: a review of 32 studies

A side effect associated with the use of some antiepileptic drugs (AEDs) is change in body weight. To evaluate the effect of lamotrigine on body weight in adult patients with epilepsy, we conducted a retrospective review of data from 463 patients treated with lamotrigine in 32 clinical trials. Mean daily dose was 259 (+/-155) mg and duration of therapy was 318 (+/-87) days. The mean change in body weight was 0.5 (+/-5) kg. Lamotrigine was associated with stable body weight in patients with epilepsy.