Studies in stress-relaxation and distensibility characteristics of small skin veins in vivo by a combined photoelectric-photographic and plethysmographic technique

Summary The phenomena of stress-relaxation and capillary outward filtration were studied in the isolated rabbit ear, perfused with blood at constant flow. The volume increase, as measured by the plethysmograph, following elevation of venous outflow pressure to 20 mm Hg for 4 min was predominantly due to capillary outward filtration in the norepinephrine constricted vascular bed (0.5 g/min). With papaverine induced dilatation (0.08 mg/min) this persistent volume increase could be attributed mainly to stress-relaxation of the veins. Engorgement of venous vessels as well as capillary outward filtration led to an increase of the ear volume that is measured by the plethysmographic technique. The photographic-photoelectric measurement of venous diameter changes was used in these experiments to distinguish intravascular from extravascular volume changes. The moduli of volume elasticity were calculated for smaller and larger veins (mean diameter 0.133 mm and 0.553 mm) with norepinephrine constriction. It has been demonstrated that the smaller veins were about seven times less distensible than the larger veins.This investigation was supported by Contract F44620-71-C-0117 of the USAF School of Aerospace Medicine, European Office of Aerospace Research (OAR), U.S. Air Force and Deutsche Forschungsgemeinschaft.This work was presented in part at the 39. Tagung der Deutschen Physiologischen Gesellschaft, Erlangen, April 1972 [Pflügers Arch. Suppl.332, R 54 (1972)].     

A fractal analysis of pyramidal neurons in mammalian motor cortex.

Pyramidal neurons in the mammalian cerebral cortex can be described by a fractal dimension (Mandelbrot, 1982), which is an objective, quantitative measure of the complexity of their soma/dendritic borders. In the cat, the fractal dimensions of lamina V cells, which include pyramidal tract neurons (PTN), indicate that these cells are more complex than other pyramidal neurons (PN) in the same region of motor cortex. The lamina V cells of the cat are also more complex than those in motor cortex of the monkey. Moreover, lamina III neurons in the monkey are more complex than monkey lamina V neurons. The fractal dimension of the intracortical axon collateral arborizations of the same pyramidal neurons indicated, in all cases, that the branching of these terminals is less complex than the branching of the dendrites of the same cells. In line with the observation that the fractal dimensions of some homologous cellular populations are different in different species, it is suggested that the fractal dimension and the degree of morphological complexity may relate to the requirement for the number of separable functions to be accommodated within one neuron. For example, as the size of the cortex and the number of neurons in a region increase, the opportunity exists within a given cortical zone, for individual functions to be segregated and for functional specialization to be accommodated with less morphological complexity of the individual neurons performing each of these functions.     

über die antikörperinaktivierende Wirkung der Antirheumatica

Zusammenfassung Die Antirheumatica Prednisolon, Phenylbutazon, Resochin, Natriumgentisinat und Natriumsalicylat hemmen die durch hämolytischen Hammelblutamboceptor und Komplement bewirkte Hammelbluthämolyse.Diese Wirkung der Antirheumatica kommt durch eine Inaktivierung des Amboceptors (Antikörpers) zustande. Das Komplement und die Hammelblutkörperchen werden bei diesen Versuchen von den Antirheumatica nicht beeinflußt.Es besteht eine strenge quantitative Beziehung zwischen Amboceptorkonzentration und Antirheumaticumkonzentration. Je höher die Konzentration des Amboceptors ist, um so stärkere Antirheumaticakonzentrationen sind zu seiner Inaktivierung nötig.Bezogen auf die wirksamen molaren Endkonzentrationen sind Prednisolon 8,5, Phenylbutazon 6,5, Resochin 5,0 und Gentisinsäure 1,5mal stärker wirksam als Salicylsäure.Wird der Amboceptor mit bestimmten Konzentrationen von Phenylbutazon, Natriumgentisinat oder Natriumsalicylat vorbehandelt, so kann mit diesem Amboceptor der Forssman-Schock (invers-anaphylaktischer Schock) nicht mehr beim Meerschweinchen ausgelöst werden. Phenylbutazon und Natriumgentisinat sind dabei etwa gleichstark wirksam, während Natriumsalicylat wesentlich schwächer wirkt als die beiden anderen Substanzen.     

Experimental Staphylococcus aureus arthritis in mice.

Staphylococcus aureus arthritis is usually caused by bacteremia and is highly destructive. Controlled studies on septic arthritis in humans are difficult to perform, because the time of onset of the infection is unknown. Animal models of bacterial arthritis make it possible to control important variables in experimental studies. We present a mouse model of S. aureus arthritis in which the intravenous administration of 10(7) cells of S. aureus LS-1 induced arthritis or osteitis or both within 3 weeks in 80 to 90% of the mice. Signs of arthritis emerged within the first few days after the injection. An interesting finding was that the S. aureus strain used in this study binds bone sialoprotein, a glycoprotein known to be specifically localized to bone tissue. This new model of S. aureus arthritis enables the study of the kinetics of joint destruction and the host-bacterium relationship as well as therapeutical approaches to septic arthritis and osteomyelitis.     

Pattern and persistence of the epitope-specific IgM response against human cytomegalovirus in renal transplant patients.

The humoral immune response against human cytomegalovirus (HCMV) was evaluated in immunocompromised patients by Western blotting (WB) based on recombinant viral envelope (gB and gH) and tegument (pp150 and pp65) proteins. Three groups of patients were investigated: (a) 74 renal transplant recipients; (b) 24 hemodialysis patients, both groups without clinical evidence of viral infections; and (c) 19 renal transplant patients with manifest HCMV infections. The results obtained suggest that (i) the WB is considerably more sensitive, recognizing the HCMV-specific IgM response rather than the enzyme-linked immunosorbent assays. An IgM response was detected in one-third of all clinically asymptomatic renal patients. (ii) The virus-specific IgM response is primarily directed against the pp150 epitope. (iii) In patients with clinically manifest HCMV disease, additional IgM reactivities are most frequently directed against the glycoprotein B epitope. (iv) The severity of HCMV infections correlates with the extent of the IgM antibody response, i.e. with the number of specific epitopes involved. (v) After transplantation, IgM reactivity and its epitope-specific pattern persist for years.     

Demonstration of Antigenic Sites in Glomeruli of Patients with Acute Poststreptococcal Glomerulonephritis by Immunofluorescein and Immunoferritin Technics

The presence and localization of antigenic sites in glomeruli of 14 patients with acute poststreptococcal glomerulonephritis (AGN) were studied by immunofluorescein and immunoferritin technics. Labeled IgG fractions from the same patients were used for the identification of antigenic sites. The staining capacity of these IgG fractions depended on the time when sera were obtained. Staining was minimal during the first week, and increased up to the fourth or fifth week. Glomeruli, however, stained only when renal tissue was obtained during the early phase of the disease. Precise localization of antigenic sites was determined with ferritin-conjugated patients' IgG. Segmental deposition of ferritin was observed in the mesangial matrix and on the endothelial side of the glomerular basement membrane. Subepithelial electron-dense deposits contained no or very few ferritin particles. In contrast, ferritin-conjugated antihuman IgG was distributed diffusely in the mesangial matrix, on the endothelial side of the basement membrane and in subepithelial deposits. These findings suggest that, during the early stage of acute poststreptococcal glomerulonephritis, free antigen is present in the glomeruli of patients with this disease.     

cDNA arrays: gene expression profiles of Hodgkin's disease and anaplastic large cell lymphoma cell lines

cDNA arrays are a powerful tool for the identification of differentially expressed genes in malignant tumors. We used this technique to study the gene expression profiles of anaplastic large cell lymphoma (ALCL) and Hodgkin's disease (HD). Gene expression of 11 lymphoma cell lines was analyzed covering 1176 cDNA sequences. Comparing these data to the expression profiles of B- and T-lymphocytes, we identified 27 genes that were deregulated in all cell lines or in a particular entity. For the establishment of gene expression profiles the 27 genes were assigned to four groups composed of genes deregulated in (i) all lymphoma cell lines, (ii) ALCL and HD, (iii) only HD, and (iv) ALCL exclusively. Our results indicate that ALCL and HD share the differential expression of at least five genes. In addition, both entities are characterized by the differentially deregulated expression of four genes in HD and seven genes in ALCL. Because the expression profiling was performed on cell lines, further studies are needed to clarify the biological significance of the differentially expressed genes.     

Reaction of surrounding gingiva to permucosal implants of dense hydroxyapatite in dogs

Experimental and histological studies on the reaction of surrounding gingiva to permucosal implants of dense calcium hydroxyapatite were carried out in dogs. Epithelial attachment and connection of supra-alveolar collagen fibres to the implant surface seemed to form a biological seal around implants similar to that around natural teeth. However, excellent oral hygiene is very important for the maintenance of this biological seal.     

Expression of superoxide dismutase and xanthine oxidase in myometrium, fetal membranes and placenta during normal human pregnancy and parturition

Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.      

Increase of bone marrow lymphocytes in systemic mastocytosis: reactive lymphocytosis or malignant lymphoma? Immunohistochemical and molecular findings on routinely processed bone marrow biopsy specimens

AIMS: To clarify the nature (reactive or neoplastic) of lesional, perifocally aggregated lymphocytes in bone marrow infiltrates of systemic mastocytosis (SM), the histopathology of which can resemble malignant lymphoma with focal bone marrow involvement, particularly low grade malignant B cell lymphoma of lymphoplasmacytic immunocytoma subtype, which frequently exhibits increased mast cell (MC) numbers. METHODS: Thirteen cases of SM and three of lymphoplasmacytic immunocytoma with predominant focal bone marrow infiltration were investigated. Immunostaining of formalin fixed, paraffin wax embedded bone marrow specimens was performed using antibodies against CD2, CD5, CD20, CD23, and CD25; kappa and lambda immunoglobulin light chains; and MC markers chymase, tryptase, and CD117 (KIT). Monoclonal rearrangements of IgH and TCRgamma were studied using seminested polymerase chain reaction (PCR). c-kit point mutation Asp816-Val was detected by PNA mediated PCR clamping and hybridisation probes. RESULTS: The lymphocytic clusters in SM contained nearly equal numbers of mature T and B cells, the latter with no coexpression of aberrant antigens, such as CD5 or CD23. Most MCs in SM cases constantly coexpressed tryptase, CD25, and CD117. No monoclonal rearrangements were seen for IgH or TCRgamma. In contrast, B cells from immunocytomas showed light chain restriction and monoclonal rearrangement for IgH, confirming their neoplastic nature. c-kit point mutation Asp816-Val was found in ten of 13 SM cases, but in none of the three immunocytomas. CONCLUSIONS: Focal accumulations of lymphocytes in the bone marrow of SM are reactive in nature and could be termed lymphocytosis. A diagnosis of SM-AHNMD/immunocytoma should not be made.