PubMed Health⌕ Search

Biomedical subjects

R Lanz

Publications and source records attributed to R Lanz.

At least 37 records · Page 2Linked to original sources
PubMed1985

Monoclonal antibodies against E- and F-type prostaglandins. High specificity and sensitivity in conventional radioimmunoassays.

Polyclonal antisera against prostaglandins (PGs) are widely used for the assessment of the biological role of these mediators, but even the most specific contain antibodies against the major metabolites and degradation products of the haptens employed. To overcome this inherent problem we produced monoclonal antibodies (mAs) against PGE2, PGF2 alpha and 6-keto-PGF1 alpha using the somatic cell hybridization technique. The mAs against 6-keto-PGF1 alpha and PGF2 alpha proved to be highly specific, but allowed only for moderate detection limits (1-2 ng) in conventional fluid phase radioimmunoassays (RIAs). One of the mAs against PGE2 permitted a 100-fold improvement in the detection limit while being almost devoid of cross-reactivity with metabolites and other structurally related PGs. These results show that highly specific mAs against PGs can be produced to improve the available RIA technique for PG quantification.

6-Ketoprostaglandin F1 alpha↗
PubMed1984

Mode of action of peripheral analgesics.

Peripheral analgesics amount to more than 95% of the analgesic market. The most important drugs of this group, salicylates, p-aminophenol derivatives, and nonacidic pyrazoles, have been used in therapy for about 100 years, their mode of action remaining unclear until today. This brief review gives a survey on the current knowledge of the therapeutic mechanisms and the molecular causes of the effects and the most important side effects of peripheral analgesics. At present, two theories cannot be rejected on the basis of current knowledge. The first and very popular concept postulates that peripheral analgesics act by inhibiting the formation of arachidonic acid metabolites. The alternative hypothesis relates the effects of the salicylates and related drugs to inhibition of various cell functions by unspecific, concentration-dependent incorporation of drug molecules in the cellular membrane. These two concepts are discussed, and the importance of the physiochemical characteristics and the pharmacokinetic behaviour of peripheral analgesics for the understanding of their effects and side effects is pointed out.

Analgesics↗
PubMed1984

Interleukin-2 production in peripheral blood mononuclear cells of patients with gastrointestinal tumors.

Peripheral blood mononuclear cells of patients with different tumors of the gastrointestinal tract (esophagus, stomach, colon, rectum), with Crohn's disease and healthy controls were analyzed for their capacity to produce mitogen induced interleukin-2 (I1-2). Tumor patients could be divided into two groups, one group exhibiting a nearly normal and a second group showing a significantly decreased production of I1-2. Most of the patients with a carcinoma of the colon were found in the low-producer group. Patients with Crohn's disease did not significantly differ from the relevant controls. Tumor patients with proven metastasis produced less I1-2 as compared to those with localized disease although the differences are not significant. When I1-2 containing supernatants of patients with tumors were additionally analyzed for the presence of prostaglandin E2, an inverse relationship could be demonstrated. Supernatants showing a suppressed activity of I1-2 exhibited increased amounts of PGE2, indicating a modulation of I1-2 production by prostaglandin E2.

Adolescent↗
PubMed1982

Adjuvant chemoimmunotherapy with LMF plus BCG in node-negative and node-positive breast cancer - intermediate report at 4 years.

A randomized surgical adjuvant trial in 242 evaluable patients with T1-3a, N0-1, and M0 breast cancer was initiated 4 years ago. The well-tolerated, oral combination chemotherapy with six cycles of Leukeran plus methotrexate plus fluorouracil (LMF) plus repeated BCG skin scarifications was used. After 4 years, the following results were seen: (1) significant increase of relapse-free (RFS) and also overall survival (S) in both pre- and postmenopausal node-negative patients versus surgical controls (RFS 91.1 vs. 701%, P = 0.003; S 96 vs. 88%, P = 0.03); (2) no significant increase of RFS or S in pre- and postmenopausal node-positive patients versus surgical controls (RFS 50.1 versus 44%, P = 0.49; S 70 versus 68 %, P = 0.9, respectively); (3) Patients receiving greater than 90% of the planned LMF dose showed significantly better survival after 4 years; and (4) Nonrandomized comparison with concurrent Swiss adjuvant studies with LMF alone indicate no beneficial or harmful effect of BCG skin scarifications in addition to the six-cycle LMF.

Breast Neoplasms↗
PubMed1981

Dissociation of tumour-promoter-induced effects on prostaglandin release, polyamine synthesis and cell proliferation of 3T3 cells.

The phorbol ester 12-O-tetradecanoylphorbol 13-acetate induces tumour promotion, inflammation, cell proliferation and prostaglandin release. Recent reports suggest that the prostaglandins released by 12-O-tetradecanoylphorbol 13-acetate (TPA) initiate a cascade of events leading to polyamine synthesis and cell proliferation. In experiments designed to test this contention, it was found that addition of TPA (1 microM to 1 nM) to confluent mouse 3T3 fibroblasts successively caused the release of prostaglandins E2 and I2, induction of the enzyme ornithine decarboxylase (EC 4.1.1.17), stimulation of [3H]thymidine incorporation into DNA, and cell proliferation. Pretreatment of the cells with the anti-inflammatory steroid dexamethasone (1 microM) or the non-steroidal anti-inflammatory drug indomethacin (1 microM) inhibited TPA-induced prostaglandin release. However, dexamethasone enhanced the other effects of TPA, whereas indomethacin was ineffective. Addition of prostaglandin E2 to the cultures did not induce ornithine decarboxylase activity and cell proliferation. Pretreatment of the cells with 1,3-diaminopropane (1 mM) or alpha-methylornithine (5 mM), inhibitors of polyamine synthesis, decreased TPA-induced ornithine decarboxylase activity without affecting DNA synthesis. TPA stimulated [3H]thymidine incorporation into DNA, even when the ornithine decarboxylase activity was completely blocked. These data suggest that the proliferative effect of TPA on 3T3 cells is independent of prostaglandin release and polyamine synthesis.

Animals↗
PubMed1979

[Surgery in the regional and district hospitals of German Switzerland].

The Regional Hospital is the hub in the surgical service for the broad population. According to its importance, it has furthermore an eminent role in instruction and postgraduate teaching. The requirements and profile for such competent medical chiefs are delineated. The broad surgical requirements, the executive duties in hospital administration, which are shared with the nursing and administration services, and the permanent personal education make it mandatory, that the position of the head surgeon be partitioned by two equally competent and polyvalent general surgeons. The ultimate responsibility for such adequate positioning rests with the political authority.

General Surgery↗