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S Jäger

Publications and source records attributed to S Jäger.

At least 73 records · Page 4Linked to original sources
PubMed1990

A novel technique for studies on the microvasculature of transplanted islets of Langerhans in vivo.

Transplantation of isolated islets of Langerhans in diabetic patients is frequently followed by an early loss of function due to acute rejection. Since the primary target of host-vs-graft reaction is the endothelium of the microvessels, it is of great importance to analyze the microcirculation of freely grafted pancreatic islets. For this purpose we present a new model, allowing for intravital microscopy of the microvasculature of transplanted islets of Langerhans. The islets are isolated from Syrian golden hamsters and DA-rats, respectively, by a modified collagenase digestion technique. Subsequently, the islets are transplanted into a hamster dorsal skinfold chamber. Using intravital fluorescence microscopy and video techniques, the microcirculation of the islet grafts can be observed repeatedly over a time period of up to four weeks. Quantitative analysis of the microhemodynamics, i.e. functional capillary density, capillary RBC-velocity and microvascular diameters, can be performed by means of a computer assisted image analysis system. In addition, the model allows for investigation of the flow behaviour of white blood cells and their interaction with the endothelium of the microvascular segments. For the first time a model is presented, enabling for in vivo analysis of the revascularization process and microcirculatory function of transplanted islets of Langerhans. Furthermore, the model allows to assess microvascular phenomena during host-vs-graft reaction as well as effects of immunosuppressive regimens.

Animals↗
PubMed1989

[The significance of vascular surgery treatment of complications following percutaneous transluminal angioplasty of the lower extremities].

In 147 patients suffering from arterial occlusive disease of the lower extremities 162 PTAs of the iliac, femoral and popliteal arteries were performed. Thirteen complications occurred in 12 patients, while surgical intervention was necessary in seven cases (4.3%). Hematoma at the site of the arterial puncture were the most frequent complications, requiring acute surgical intervention (n = 3). In two patients, acute vascular occlusion after PTA required bypass operation and thrombendarteriectomy, respectively. In one patient, presenting with an iliac stenosis, PTA was performed using a transaxillar approach and was complicated by an axillar hematoma due to the ruptur of the arteria subscapularis. Furthermore, one patient with an extended hematoma of the abdominal wall required surgical intervention. The results presented indicate that PTA of the lower extremities for treatment of arterial occlusive disease is a procedure with low risk. Complications, which require acute operative therapy, can be treated mostly successful by small surgical interventions.

Angioplasty, Balloon↗
PubMed1987

Prolongation of graft survival in allogeneic islet transplantation by (-) 15-deoxyspergualin in the rat.

The effect of 15-Deoxyspergualin, a novel drug which has been described to have anti-tumour activity, on allogeneic graft survival (Dark Agouti----Lewis rats) after pancreatic islet transplantation was tested. A marked prolongation of graft survival could be shown using doses of 1.0, 2.5 and 5.0 mg Deoxyspergualin/kg on day 0 until day +9 post transplantation. A maximum of 55.6 days (average) survival time was observed using 2.5 mg/kg Deoxyspergualin compared to 5.2 +/- 0.6 days without immunosuppression. Using the chemiluminescence reaction of recipient monocytes after islet transplantation, a marked suppression of the monocyte system exceeding the treatment period could be observed. Since, in contrast to cyclosporin, B-cell toxicity could not be shown, the new drug seems to be a hopeful step towards successful allogeneic islet transplantation for treatment of diabetes.

Animals↗
PubMed1987

Competitive enzyme-linked immunoassay for the quantitation of platelet-associated immunoglobulins (IgG, IgM, IgA) and complement (C3c, C3d) with polyclonal and monoclonal reagents.

A competitive enzyme-linked immunoassay (CELIA) was developed for the quantitation of platelet-associated immunoglobulins and complement proteins. The use of unlabeled polyclonal rabbit or monoclonal antibodies to human immunoglobulins and enzyme-labeled anti-mouse or anti--rabbit IgG (double-step technique) resulted in a higher sensitivity compared to the single-step technique using only enzyme-labeled anti-human immunoglobulin antibody preparations. Sensitivity and results obtained by both techniques were compared. The range of normal values for platelet-associated IgG, IgM, IgA, C3c and C3d was assessed upon a large number of normal blood donors. When platelet-associated IgG was concomitantly assayed with polyclonal and monoclonal anti-IgG by the double-step technique on platelets obtained from normal donors and thrombocytopenic patients, identical results were obtained with both reagents. Problems related to the quantitation of immunoglobulins on platelets with different assays and antibody preparations are discussed.

Antibodies, Monoclonal↗
PubMed1985

Growth of human bronchial carcinomas in nude mice.

Two hundred and thirteen lung tumours of primary site and 42 metastases were heterotransplanted into nude mice with an overall success rate of 44%. There were differences in success between the histological types. Squamous cell and adenocarcinoma had the highest success rate (51% and 43%, respectively) whereas large cell and small cell carcinoma had a lower success rate (38% for both). The average volume doubling times in the first passage in nude mice ranged from 8.2 in large cell carcinomas to 18.9 days in adenocarcinomas. In subsequent passages an increase in growth rate was found, the overall average doubling time falling from 14.5 days in the first passage to 7.1 days in the second passage. In a study with 171 non-small cell lung carcinomas (NSCLC), the growth data in nude mice were correlated with the clinical data of the corresponding patients. A relationship between the growth parameters in nude mice and prognosis of patients could not be found.

Adenocarcinoma↗
PubMed1983

[Assessment of therapeutic success of a specific immunotherapy of grass pollen allergy].

So far it has not been possible to clearly objectify the success of a specific immunotherapy. The aim of the study is to determine which immunological parameters and which clinically biological observations can be used in order to verify a therapeutic success. In four different groups of patients suffering from grass pollen allergy, different specific immunotherapies were carried out pre-seasonally. Continuous observations of patients symptoms together with continuous measurements of the concentration of pollen in the air, of the usual whereabouts of the respective patients, as well as the determination of specific IgE and IgG antibodies before and after the immunotherapy, and the observation of the IgD titre were used as basis of assessment of the efficacy of the specific immunotherapy. Statistical evaluation showed that only the pollen-exposure measurement as compared to the complaints of the individual patients can yield exact information on the therapeutic success. The immunological parameters, in particular the determination of the specific IgG antibodies, are not statistically related to the actual therapeutic efficacy.

Humans↗
PubMed1981

Influence of aerobiology and weather on symptoms in children with asthma.

Local and central European weather, pollen (Castanea and Poaceae) and spore (alternaria and cladosporium) counts, and asthmatic complaints and drug requirements (expressed as "attack score") were correlated in a group of 40 asthmatic children (21 with recurrent symptoms) during a summer holiday camp for 6 weeks. It was shown that there are significant correlations between the cumulative 24-hour pollen count over 6 weeks and the attack frequency. 2-Hourly counts or daily counts did not correlate with complaints. Consecutive 10-day averages of attacks and pollen and spore counts showed good agreement. The influence of local weather was negligible. Low pressure gradients or high atmospheric pressure was not beneficial. Improvements of lung function are ascribed to training effects.

Adolescent↗
PubMed1980

[The determination of the aggressiveness of allergizing types of pollen (author's transl)].

It is a well-known fact that the same amount of various pollen does not cause the same intensity of complaints in different patients with hay fever. This empirically obtained fact has been made objective and applied to the needs of practical allergology. From 1976 to 1978 qualitative and quantitative measurements were carried out on the pollen content of the air in Vienna. At the same time 300 patients with hay fever, who had been thoroughly investigated, made daily recordings of their complaints during the pollen season. A comparison of the two sets of data shows that they correspond well at the time of grass blossoming, yet differ strikingly during the blossoming of trees and herbs. Therefore, the grass pollen count is taken as the basis for any further calculations. By adjusting the amount of all the other types of pollen to the patients' complaints, "correction factors" are established for those types of pollen that are allergologically most important. These correction factors indicate the relative aggressiveness of the individual types in comparison with the grass pollens. In addition, the frequency of sensitization to individual types of pollen was determined in 500 patients at the First Otolaryngological Department of the University Hospital of Vienna. By multiplying the frequency by the correction factor we arrive at the "potency factor" as a measure of the allergological significance of the respective pollen type. The threshold value is indicated as a further parameter. The threshold value is the pollen count per cubic metre of air required to elicit complaints in the average number of sensitized patients. The threshold value for grass pollens is 50 per cubic metre of air; hence the following formula is derived for the determination of the threshold value: (formula: see text). The potency factor and the threshold factor are valuable parameters in the diagnosis, prophylaxis and therapy of hay fever.

Air Pollution↗
PubMed1980

[Occupational immediate type allergy to hemp pollen and hashish (author's transl)].

A 26-year aged non-atopic criminological technician reacted to hemp (Cannabis sativa) and hashish with urticarial eruptions on hands and lower arms, rhinitis and conjunctivitis. Rubbing tests with pollenrich hashish were strongly positive. As hemp antigens were unavailable a hyposensitization therapy with hop (Humulus lupulus)--a plant belonging to the Cannabacea family--was begun.

Adult↗
PubMed1980

[A modified therapy of hayfever with a depot-preparation (author's transl)].

70 patients with clinically and immunologically verified grass pollen allergy received immunotherapy for the first time in 1977 and 1978. The 70 patients were divided into 3 groups. Group 1 received 18 injections of a 7 grass pollen extract (semi-depot, Allpyral). Group 2 was treated with 3 injections of a tyrosine adsorbed grass pollen vaccine (Pollagen) immediately preseasonal and Group 3 received 5 injections of the same. Therapy was from September 1977 to May 1978. All patients completed dairy cards on a daily basis for the 1978 season including data on additional medication and areas visited. The air pollen concentration was monitored at various sites in Vienna and surrounding area. Reviewing the symptoms of the 3 patients we noted stronger symptoms reported in Group 2 than in Group 1. There was no significant difference in severity of symptoms in Group 1 and Group 3. The data indicate that a treatment with a course of 5 injections of a tyrosine adsorbed grass pollen vaccine is better than a course of 3 injections of the same product, and equivalent to a standard course of therapy with a semi-depot product.

Delayed-Action Preparations↗
PubMed1980

[The relevance of cereal grain pollen in hayfever (author's transl)].

Our studies indicate that rye pollen appears to be an important factor in hayfever in Austria. High air concentration of rye pollen are not only found in the immediate vicinity of the cultivated fields, but also at considerable distance from these fields. It is important to note that the rye plant produces about 8 to 35 times more pollen per anther than the wheat plant. Corn (Zea mays) pollen is found in lower concentrations as an airborn pollen because of its density. The importance of rye pollen in hay-fever has been substantiated in a clinical study and by the "biological exposure test".

Edible Grain↗
PubMed1980

[Reduced allergen immunotherapy of grass pollinosis (author's transl)].

An excellent model for investigating the maximization of specific immunotherapy is grass pollen allergy. Treatment is more effective when the number of component antigens used are reduced. We know that rye and cocksfoot pollen carry major antigens of grass pollen. A controlled clinical study was carried out with 128 patients divided into 5 groups as follows: Group 1 - treatment with a mixture of 7 grass pollen extracts (Allpyral). Group 2 - treatment with a cocksfoot pollen extract (Allpyral). Group 3 - treatment with a rye pollen extract (Allpyral). Group 4 - treatment with a mixture containing 50% rye pollen and 50% cocksfoot (Allpyral). Group 5 - was control group without immunotherapy. In brief, groups 1 to 4 showed better results than group 5. Group 2-cocksfoot, group 3-rye and group 4-cocksfoot-rye showed significantly better results than group 1-7 grass pollen extract. When severe symptoms were present the group 4, rye-cocksfoot treatment was significantly better than the others. This example illustrates the fact that specific allergen use improves the success of immunotherapy. In grass pollen allergy treatment cocksfoot and rye are of particular importance.

Adult↗