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PubMed1988

Leukocytes, eosinophils and complement function during hemodialysis with polysulphone and polymethylmethacrylate membranes: comparison with cuprophan and polyacrylonitrile.

The biocompatibility of the two new dialysis membranes, polysulphone (PS) and polymethylmethacrylate (PMMA), was evaluated versus cuprophan (CUP) and polyacrylonitrile (PAN) by studying the in vivo effects of the four different membranes on leukocyte counts, eosinophil levels and complement function both in the presence and absence of dialysis fluid. Complement function was also examined in vitro by studying the generation of chemotactic factors, whole complement activity and C3d serum conversion. Passive absorption of complement fractions by membranes has completed in vitro studies. PS, PMMA and PAN showed a higher biocompatibility than CUP, even if slight differences can be observed: PS showed a PAN-like biocompatibility pattern with a relatively high absorption of complement factors by the membrane and without complement activation. On the other hand, PMMA showed a CUP-like pattern and caused complement activation, even though to a lower intensity than CUP. PMMA biocompatibility appears to stand in-between CUP and the other two synthetic membranes PS and PAN. Our results confirm the important role played by membrane-induced complement activation on hemodialysis leukopenia. Dialysis fluid does not have a significant influence on membrane biocompatibility, but represents the major factor in determining intradialytic eosinopenia. Eosinophils seem to represent a more important marker of dialysis than of membrane biocompatibility.

Acrylic Resins↗
PubMed1995

Renal lesion of type Ia glycogen storage disease: the glomerular size and renal localization of apolipoprotein.

In order to investigate the glomerular size and renal localization of apolipoprotein in type Ia glycogen storage disease, a renal biopsy was performed in two proteinuric patients. Histopathological examination of the biopsy specimens revealed focal sclerotic glomerular sclerosis in both patients. The mean glomerular area was 21.6 +/- 11.6 x 10(3) microns 2, indicating enlargement of the glomeruli. Immunohistochemical staining of the specimens for apolipoprotein showed localization of apolipoprotein AI on the inner side of the glomerular capillary wall, and in proximal tubular epithelial cells. In one patient with a history of several episodes of hypoglycemia, treatment with corn starch improved the carbohydrate and lipid metabolic profile and reduced the daily urinary protein excretion from 2.23 to 0.5 g. These results suggest that focal sclerotic glomerular lesions associated with type Ia glycogen storage disease may be related to disorders of carbohydrate and lipid metabolism.

Adult↗
PubMed1991

Analysis of proteins eluted from hemodialysis membranes.

To further investigate the types of interactions occurring between blood and hemodialysis membranes, proteins were sequentially eluted from used dialysers. Four different membranes (cuprophan, hemophan, cellulose acetate and polyacrylonitrile) were successively treated with a hydrogen bond cleaving agent (10 M urea), an ionic detergent destabilizing the hydrophobic interactions between apolar groups (SDS solution), and a hydroxylamine solution at alkaline pH to release postulated covalently bound C3 fragments. The eluted proteins were analyzed by SDS-PAGE and immunological techniques. Total protein determinations demonstrate different behaviour of the membranes as regards the 'protein cake'. Electrophoretic analysis suggests that qualitative and quantitative differences in the binding of the blood proteins are related to the membrane material. Complement fragment studies indicate that the complement activating potential of the dialysis membrane may not be determined by the availability of potential binding sites for activated C3b. An attempt is made to correlate these results with the biocompatibility concept.

Acrylic Resins↗
PubMed1985

Activation and cell cycle control of murine B lymphocytes.

The cell cycle of activated murine B lymphocytes (B cells) is controlled by the occupancy of surface membrane-bound immunoglobulin (Ig) and by two types of growth factors, called alpha and beta factors. These growth factors are produced in an endocrine fashion by the interaction of helper T lymphocytes (T cells) with antigen-presenting macrophages (A cells). Antigen is taken up, processed and presented on the surface of A cells in the context of class II major histocompatibility complex (MHC) glycoproteins. Helper T cells recognize this association of antigen and class II MHC molecules. A cells produce alpha factors and T cells produce beta factors. The molecular nature of these factors and of the corresponding receptors on B cells has yet to be elucidated, although it can be shown that the complement component C3d replaces alpha factor action. Resting, G0 phase B cells are refractory to the action of alpha and beta factors. They have to be excited, i.e. rendered susceptible to the action of these factors. This can be achieved by the interaction with helper T cells that recognize antigen, bound by surface membrane Ig, in the context of class II MHC glycoproteins on the surface of resting G0 B cells. Excitation can also occur in a polyclonal fashion by cross-linking of surface Ig with immobilized, Ig-specific antibodies, or by the interaction with polyclonal activators of B cells, such as lipopolysaccharides. Entry into the cell cycle is asynchronous. Activated, cycling B cells can be synchronized by size separation, using velocity sedimentation. Synchronized B cells will retain their synchrony for several divisions, when they are stimulated by immobilized Ig-specific antibodies, alpha and beta factors. They divide every 20 h at 37 degrees C. Omission of either of the three stimuli arrests B cells, though at different points in the cell cycle. Three restriction points are found: the first occurs immediately after mitosis and is controlled by the binding of immobilized Ig-specific antibodies to surface membrane-bound Ig.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

On the diagnosis and pathogenesis of intramural maxillary cysts.

In order to study the etiology of the intramural maxillary cyst, which is the origin of the choanal polyp, an antrotomy was performed on 27 patients with such cysts. The cyst-fluid was analysed with respect to protein distribution and bacterial growth. The findings indicate an inflammatory process characterized by high concentrations of immunoglobulins and by consumption of complement and antiproteases. The growth of bacteria, primarily an oral flora found in the cyst-fluids studied, and the sites of cyst attachment, may indicate an epithelial residue of the dental list as the origin of the intramural cyst. It is further suggested that bacterial substances will provoke an inflammatory response, giving rise to an expansion of the cyst. In all cases studied, the cyst-fluid was capable of gelling after a couple of minutes at room temperature. This observation seems to be a reliable diagnostic procedure at antral aspiration, distinguishing the cyst-fluid from the serous transudate of the serous sinusitis, which according to our results, does not have this capacity to form a gel.

Adolescent↗
PubMed2000

Passive transfer of demyelination by serum or IgG from chronic inflammatory demyelinating polyneuropathy patients.

Chronic inflammatory demyelinating polyneuropathy (CIDP) is regarded as an autoimmune disorder, but no clearly defined autoimmune mechanism has been described. Although most patients respond to plasma exchange, no convincing role for autoantibodies has yet been demonstrated. In this study, we have successfully passively transferred disease using sera and purified IgG from 4 of 12 patients responsive to plasma exchange by bypassing the blood-nerve barrier by intraneural injection or opening it by activated T cells. The sera from CIDP patients or purified IgG produced marked conduction block and demyelination, but normal sera or IgG or that from patients with multiple sclerosis or other neuropathies did not. These observations strongly support an important role for anti-myelin/Schwann cell autoantibodies in the pathogenesis of CIDP at least in some patients.

Action Potentials↗
PubMed2000

Myelin widenings and MGUS-IgA: an immunoelectron microscopic study.

A few studies have reported a variety of nonspecific histological lesions in patients with IgA monoclonal gammopathies and polyneuropathy. In our case, using electron microscopy, we observed widenings of the myelin lamellae identical to those commonly described in IgM neuropathies with anti-myelin-associated glycoprotein activity. Using immunoelectron microscopy, we demonstrated a direct involvement of IgA in myelin lesions. The search for a direct link between monoclonal dysglobulinemia, regardless of type, and polyneuropathy is important and may influence treatment.

Aged↗
PubMed1996

Chronic inflammatory demyelinating polyneuropathy in dogs and cats.

Over the past several years, we have accumulated data on a spontaneous demyelinating peripheral neuropathy that is not well identified in domestic animals. This disorder occurs in dogs and cats of either sex and does not appear breed-related. Onset of signs is usually insidious and the course is typically chronic, sometimes relapsing, and often slowly progressive. Mature animals of any age may be affected. Clinical signs include tetraparesis, sometimes progressing to tetraplegia, stumbling gait, and hyporeflexia. Motor nerve conduction velocities are decreased. Pathologically, changes in teased single fibers from peripheral nerves are dominated by multifocal paranodal demyelination. Scattered, thinly myelinated fibers are seen on semithin sections. Ultrastructural studies reveal macrophages within myelinated fibers stripping the myelin sheaths, naked and remyelinating axons, and focal/multifocal endoneurial mononuclear cells. Indirect immunofluorescence revealed positive IgG staining in peripheral nerve myelin sheaths from two dogs. The course of the disease, clinical signs, electrophysiology, and pathology have similarities to chronic inflammatory demyelinating polyneuropathy in people.

Age Factors↗
PubMed2002

DNA gene fusion vaccines against cancer.

The ability of DNA vaccination to induce effective immune responses has been shown in a range of preclinical disease models. However, the potency of DNA vaccines must be further improved for their use in patients. DNA fusion vaccine strategies, whereby target antigens are genetically linked to immuno-enhancing molecules, are currently being explored. The ease of DNA manipulation has allowed incorporation of a wide variety of molecules able to promote antigen uptake, processing and presentation by professional antigen-presenting cells, to provide critical CD4 T-cell help and to activate more effective immune effector pathways. These strategies are particularly important for cancer vaccines to increase their immunogenicity and to overcome tolerance.

Animals↗
PubMed1991

Attenuation of intra-operative surgical stress response has no influence on post-operative degranulation of polymorphonuclear granulocytes.

Degranulation of polymorphonuclear (PMN) granulocytes, complement activation, and the endocrine metabolic response to hysterectomy were compared in two groups of patients receiving either general anaesthesia (GA group) or combined epidural analgesia and general anaesthesia (GAE group). The B-leucocyte and the cortisol responses were attenuated in the GAE group. There was no sign of complement activation. The post-operative rise in elastase-alpha-1-proteinase levels 4 h post-operatively on the first, second and third post-operative days was similar in the two groups. Plasma lactoferrin values were significantly elevated 4 h post-operatively and reached pre-operative values on Day 1 in both groups. Attenuation of the surgical stress response during uncomplicated hysterectomy did not influence the post-operative increase in proteinase activity. Mediators generated at the site of surgical trauma may account for the PMN degranulation observed after major surgery.

Adult↗
PubMed1989

[Pemphigus herpetiformis--the value of simple diagnostic measures].

Herpetiform pemphigus is a rare variety of pemphigus vulgaris. Although the final diagnosis requires thorough clinical, histological and immunological investigations, there are simple examinations which may be carried out at once (such as assessment of blister stability, negative Nikolski's sign, predominance of eosinophils, spongiotic and non-acantholytic epidermal cells in the Tzanck smear). These ad hoc findings may help the practising dermatologist to tell herpetiform pemphigus from other blistering diseases. We discuss and evaluate the various diagnostic procedures regarding herpetiform pemphigus.

Aged↗
PubMedDate not supplied

The effect of physical training on patients with rheumatoid arthritis: changes in disease activity, muscle strength and aerobic capacity. A clinically controlled minimized cross-over study.

For decades, physical training of rheumatoid arthritis (RA)-patients has been controversial, especially for patients with active disease. The aim of this study was to investigate whether RA-patients could receive graduated training without increasing the activity of the disease. In a controlled cross-over study the effect of graduated progressive training has been evaluated in 18 RA-patients with moderately active disease. The training was performed twice weekly with aerobic conditioning and strength exercises progressing to strenuous exercises over an 8-week period. The design was a crossover project with two groups obtained by minimisation. After training the patients had significantly fewer swollen joints than before. Training of the muscles acting over the swollen joints resulted in more than a 35% decrease in the number of swollen joints. The hemoglobin level increased significantly after the training period. The erythrocyte sedimentation rate, the complement factor C3d, and the number of sore joints remained unchanged. A decrease in the need for medicine was non-significant. From this study it appears that RA-patients with some activity are trainable without aggravating the disease, even in the chronically swollen joints. The rheumatoid arthritis activity decreased with fewer swollen joints and higher hemoglobin level after training.

Adult↗
PubMedDate not supplied

Prekallikrein activation in the adult respiratory distress syndrome.

Prekallikrein is the zymogen form of plasma kallikrein, a proteolytic enzyme of the contact system of blood coagulation, fibrinolysis and kinin formation. To assess whether prekallikrein was activated in the adult respiratory distress syndrome (ARDS), we examined plasma samples from 12 critically ill patients including five individuals with ARDS. Using the ratio between functional prekallikrein and prekallikrein-kallikrein antigen as an index for prekallikrein activation, we found that prekallikrein was extensively activated in patients with ARDS, while this was significantly less in the case of critically ill patients without ARDS. Following activation of prekallikrein in plasma, kallikrein reacts with its substrates and with protease inhibitors, among which the alpha 2-glycoprotein C1-inhibitor. Thus, we examined whether C1-inhibitor of critically ill individuals was modified in a way suggesting that it had reacted with kallikrein. Such a modification was found in the five patients with ARDS, while it was not detectable in the seven patients without ARDS. This observation further confirmed the activation of prekallikrein in patients with ARDS. We suggest that plasma kallikrein-mediated reactions, which include bradykinin release and neutrophil activation, may contribute to the pathogenesis of ARDS.

Adolescent↗
PubMed1983

Heterogeneity in electrophoretic mobility of C3-derived molecules expressing D but not C-epitopes following in vivo activation of the complement system.

Four different populations of C3-derived molecules expressing D but not C epitopes were identified following in vivo activation of the complement system. The four molecular forms, differing in electrophoretic migration velocity, were assigned the nos. 1, 2, 3 and 4 after decreasing electrophoretic mobility. Analysis of the time-dependent changes in the relative concentration of the different molecular forms demonstrated an increase in the plasma concentration of population 4 and a decrease of populations 2 and 3, whereas form 1 remained rather constant after acute activation of the complement system.

Animals↗