Prognostic factors after cervical lymph node dissection for cutaneous melanoma metastases

Cervical lymph node dissection (CLND) is the surgical therapy used for the local control of regionally metastasized cutaneous head and neck melanoma. This study evaluated the outcome of patients undergoing CLND at our institution in order to determine the prognostic factors for recurrence-free survival and overall survival after this procedure. The hospital records of 66 patients with histologically proven lymph node metastases who underwent curative or palliative CLND between 1982 and 2004 were analysed. The characteristics of the patients, the primary tumour and the surgical procedure were recorded. During follow-up, the incidence of local or distant recurrences was recorded and the survival was determined. Of the 66 patients, a (modified) radical neck dissection was performed in 20 and a selective procedure in 46. The 5-year actuarial overall survival was 26% and the recurrence-free survival was 22%. Neither the primary tumour characteristics nor the extent of surgery was of prognostic value; the number of positive nodes affected both the overall survival (P=0.046) and overall recurrence-free survival (P<0.001). Selective CLND is the recommended procedure for patients with cervical metastases of cutaneous melanoma. The number of positive lymph nodes significantly affects the outcome of the patients.     

Catecholamine-induced pulmonary edema and pleural effusion in rats--alpha- and beta-adrenergic effects

We investigated the contribution of alpha- and beta-adrenergic pathways to catecholamine-induced pulmonary edema and the role of pleural effusion in preventing alveolar edema. Female Sprague-Dawley rats received continuous intravenous infusion of norepinephrine and of separate alpha- or beta-adrenergic stimulation over 6-24 h. We performed heart catheterization in vivo and excised post mortem lung tissue for histological analysis. Interleukin (IL)-6 and total protein concentrations were determined in serum, pleural fluid (PF) and bronchoalveolar lavage fluid. alpha-Adrenergic treatment increased right ventricular systolic pressure (RVSP) and total peripheral resistance (TPR) and caused severe alveolar edema associated with IL-6 activation in serum and diffuse pulmonary inflammation. PF amounts were moderate (0.9+/-0.2 ml). beta-Adrenergic stimulation also increased RVSP but decreased TPR. Interstitial but not alveolar edema and focal inflammation without IL-6 activation developed. Large PF amounts (6.2+/-1.5 ml) occurred which were considered to prevent alveolar edema. We conclude that both alpha- and beta-adrenergic stimulation contribute to pulmonary fluid shifts in rats, but alpha-adrenergic pathways cause more acute and more severe lung injury than beta-adrenergic mechanisms.     

The C terminus of the human C5a receptor (CD88) is required for normal ligand-dependent receptor internalization

The biological effects of the potent inflammatory mediator C5a, a complement split product, on human neutrophils and monocytes are limited by the rapid internalization of its specific receptor (C5aR, CD88). The C terminus of the C5aR is phosphorylated after stimulation with C5a of phorbol ester, and this phosphorylation might lead to receptor internalization. In this context, we have studied the effects on C5aR internalization of C5a, phorbol 12-myristate 13-acetate (PMA), the protein kinase inhibitor staurosporine, and pertussis toxin on rat basophilic RBL.2H3 cells stably transfected with the human wild-type or mutant C5aR. C5aR mutants lacked either part of the cytosolic C terminus, including suggested major phosphorylation sites, or a putative phosphorylation motif for protein kinase C in the third cytosolic loop. Additionally, agonist-induced internalization was analyzed on HEK293 cells co-transfected with C5aR and the pertussis toxin-resistant G protein alpha subunit, Gα16. Staurosporine-sensitive agonist-dependent C5aR internalization could be detected, suggesting that C5aR phosphorylation, most likely of the C terminus, participates in this type of internalization. In contrast, PMA-induced C5aR internalization seems to be independent of putative phosphorylation sites in either the truncated section of the C terminus or the third cytosolic loop. The phorbol ester-induced C5aR internalization may, therefore, be caused by an indirect and less specific effect of protein kinase C on the internalization machinery. Manipulation of the pertussis toxin-sensitive or -resistant G protein-dependent signal transduction had no effect on ligand-induced internalization.     

Age-related increase of CD45RO+ lymphocytes in physically active adults

The CD45RO phenotype of peripheral blood CD4⁺ and CD8⁺ lymphocytes were determined in physically active males (n = 171) and females (n = 70) ranging in age from 15–68 years. Direct immunofluorescence and dual color flow cytometry was performed for analysis. Absolute cell numbers (r = 0.473) and percentages of CD4⁺ CD45RO⁺ (r = 0.648) within the CD4⁺ population, percentage of CD8⁺ CD45RO⁺ cells within the CD8+ lymphocytes (r = 0.498) and total lymphocyte number (r = ?0.242) correlated significantly (p < 0.001) with age. We conclude that the age-related increase of CD45RO⁺ T cells indicates a gradual increase of activated T cells.     

Induction of putative tumor-suppressing genes in Rat-1 fibroblasts by oncogenic Raf-1 as evidenced by robot-assisted complex hybridization

The growth factor receptor-dependent protein kinase Raf-1 is activated by GTP-bound Ras, thereby activating the mitogen-activated protein kinase pathway. To study the role of Raf in transformation we transduced Rat-1 cells with a tetracycline-regulatable retroviral vector encoding the constitutively active oncogenic C-terminal fragment of the human Raf-1 protein. Using subtractive hybridization of mRNAs from induced and noninduced cells and robot-assisted screening by complex hybridization, Raf-induced genes with various different characteristics of induction were investigated. Among the strongly induced genes were those involved in carcinogenesis such as metalloproteinases 3, 10 and 13, cathepsin L, ornithine decarboxylase, and putative tumor-suppressing genes such as monocyte chemoattracting protein 1, interferon-induced protein 10, a recently identified 2'-5' oligoadenylate synthetase-like protein, and plasminogen activator inhibitor type 2. Other components of the plasminogen activator system were not induced. Plasminogen activator inhibitor type 2 is a down-regulator of the proteolytic cascade consisting of various metalloproteinases, some of which are induced by a carboxy-terminal Raf mutant (RafCT). In conclusion, RafCT induces factors which act in a conflicting manner in respect of carcinogenesis, especially within the proteolytic system of the extracellular matrix.     

Release and detection of dental corrosion products in vivo: development of an experimental model in rabbits

An experimental animal model was developed to investigate the release of metal ions from nonprecious dental alloys. Cast specimens of five Ni-Cr-alloys and Co-Cr-alloys were implanted intramuscularly in rabbits for periods of 2, 4, 8, and 12 weeks. The concentrations of nickel, chromium, cobalt, and molybdenum in the implant-loaded muscles were determined by electrothermal atomic absorption spectrometry (AAS) and neutron activation analysis (NAA). Reference muscle samples of each animal were analyzed to determine the individual control values. Significant increases in the tissue concentrations of these metals occurred in the immediate vicinity of the implants. Concentration gradients of the corrosion products were found between the implant contact tissue and the implant periphery (p less than 0.001). Tissue concentrations of nickel and chromium correlated (r less than 0.7). Microprobe analysis before and after implantation of the alloy specimens indicated an even corrosive loss of the alloy surfaces and changes in the surface element distributions. Advantages and limitations of this animal model are discussed, as well as its application in future studies.     

Combining fast response and low cost in an Intensive Care Unit viewing station

This paper describes a prototype viewing station for the Intensive Care Unit (ICU) that combines a low cost with a fast response for the primary viewing tasks. A single monitor is used together with the possibility to switch to another image on the same screen instantaneously. To reduce the time for image retrieval and display, the viewing station anticipates the need for particular images, and preloads these from the disk into the internal memory whenever the computer has some idle time. Preliminary experience suggests that the use of a single monitor is no fundamental limitation for this application. Most of the time, the system can anticipate which images will be required shortly. This has an important impact on the user efficiency.     

The basal forebrain cholinergic system in the raccoon

The distribution of neurons displaying choline acetyltransferase (ChAT) immunoreactivity was examined in the raccoon basal forebrain using a rabbit antiscrum and a monoclonal antibody. Alternating sections were used for Nissl staining. ChAT-positive neurons were arranged in a continuous mass extending from the medial septum to the caudal pole of the pallidum. Based upon spatial relations to fibre tracts, the clustering of neuronal groups, and cytological criteria, the basal forebrain magnocellular complex can be subdivided into several distinct regions. Although clear nuclear boundaries were often absent, the ChAT-positive neurons were divided into: the nucleus tractus diagonalis (comprising pars septi medialis, pars verticalis and pars horizontalis); nucleus praeopticus magnocellularis; substantia innominata; and the nucleus basalis of Meynert. Comparison with Nissl-stained sections indicated the presence of varying proportions of non-cholinergic neurons clustered or arranged loosely within these basal forebrain subdivisions. These data provide a structural basis for studies concerned with the topographical and physiological aspects of the raccoon basal forebrain cholinergic projections and its comparison with the basal forebrains of other species.