PubMed Health⌕ Search

Biomedical subjects

J Müller

Publications and source records attributed to J Müller.

At least 1,027 records · Page 57Linked to original sources
PubMed1965

Effects of related anionic detergents on flagellation, motility, swarming, and growth of Proteus.

The effects of a series of sodium alkyl sulfates (C(4) to C(16)) on flagellation, motility, swarming, and growth of Proteus were examined. The concentrations of the various sodium alkyl sulfates completely inhibiting the swarming phenomenon (on solid medium) and motility (in liquid medium) were in the same order of magnitude. The inhibiting effect of the detergents examined increased from sodium hexyl sulfate (inhibitory concentration, 20 to 30 mmoles per liter) to sodium tetradecyl sulfate (inhibitory concentration, 0.1 to 0.5 mmoles per liter). Flagella were produced neither in liquid nor on solid medium at these concentrations as could be observed by electron microscopy. At concentrations where motility was not impaired, intact flagellation could be observed. At a concentration of 0.1 mmole per liter, sodium tetradecyl sulfate completely inhibited the motility of Proteus in the liquid medium employed without impairing growth.

Carbon Isotopes↗
PubMedDate not supplied

Possible reasons for failure of conventional tests for diagnosis of fatal congenital toxoplasmosis: report of a case diagnosed by PCR and immunoblot.

Diagnosis of subclinical congenital toxoplasmosis has to rely on serological methods or isolation of the parasite. We present a case of congenital toxoplasmosis, in which conventional tests failed to establish the diagnosis. It was shown that this infant developed an intrathecal antibody response that was directed only against one of two Toxoplasma gondii strains used for routine diagnosis. In contrast to conventional tests, the diagnosis of cerebral toxoplasmosis could be established by using immunoblot and polymerase chain reaction (PCR). We therefore suggest that in unclarified cases, PCR and immunoblot, using at least two different strains of T. gondii, should be considered as additional tools for diagnosis of an infection with Toxoplasma and that examination of cerebrospinal fluid may be critical.

Adult↗
PubMedDate not supplied

Apical uptake of choline and cationic drugs in epithelial cell lines derived from human placenta.

Many cationic drugs are administered during pregnancy and might enter the fetal circulation by transplacental passage. This study was performed to characterize the apical uptake of choline and several cationic drugs at cultured epithelial cells of the human placenta. Total uptake of [3H]choline in BeWo cells was H(+)-independent and to 65% Na(+)-independent. Uptake rates into both cell lines were saturable with Michaelis-Menten constants (Kt) of 108 microM (BeWo) and 206 microM (JEG-3), respectively. Cationic drugs such as etilefrine, clonidine, ranitidine, diphenhydramine, imipramine and butylscopolamine strongly inhibited the [3H]choline uptake in BeWo cells and in JEG-3 cells, with Ki values ranging from 0.18 to 3.3 mM. In contrast, tetraethylammonium had only little inhibitory effect on [3H]choline uptake. Using high-performance capillary electrophoresis for quantitative analyses, uptake of etilefrine and diphenhydramine into JEG-3 or BeWo cells was measured. Diphenhydramine was transported into JEG-3 cells in a saturable manner with a Kt value of 0.75 mM. In the presence of sodium, diphenhydramine uptake at BeWo cells was inhibited to 69% by the addition of 50 mM choline chloride. Like choline uptake, total diphenhydramine uptake was to 68% Na(+)-independent in BeWo cells. We conclude that in addition to choline, several cationic drugs, in particular diphenhydramine, are taken up by placental epithelial cells from the maternal blood by carrier-mediated processes. Etilefrine, clonidine, ranitidine, diphenhydramine and butylscopolamine interact with the Na(+)-independent placental choline transport system.

Biological Transport↗
PubMedDate not supplied

Cyclin D-cdk6 complex is targeted by p21(WAF) in growth-arrested lymphoma cells.

Normal human B lymphocytes are sensitive to the growth-inhibitory action of transforming growth factor beta1 (TGFbeta1) whereas malignant B lymphoma cells are mostly resistant to TGFbeta1 effects. We examined the phosphorylation status of retinoblastoma protein and the activity of G(1) cyclin-dependent kinases (cdk) in TGFbeta1-sensitive malignant follicular lymphoma cells during the TGFbeta1 treatment. The kinase activity of cdk2, cdk4, and cdk6 was significantly reduced and hypophosphorylation of pRb on serine 795 (S795) and threonine 373 (T373) was observed. We examined the composition of cdk complexes and the level of cdk inhibitors to explain the inhibitory action of TGFbeta1 toward cdk activity. Both cdk4 and cdk6 were notably dissociated from cyclin D cofactors, while cyclin E-cdk2 complexes remained coupled in TGFbeta1-treated cells. TGFbeta1-induced growth arrest was associated with notably increased binding of p21(WAF1) to cdk4 and cdk6. No induction of cdk-inhibitor molecules of INK family was observed in TGFbeta1-treated DoHH2 cells. As shown, TGFbeta1-induced growth arrest of malignant B cells was associated with the activation of CIP/KIP family members of cdk inhibitors.

Blotting, Western↗
PubMedDate not supplied

Combination of endoscopic argon plasma coagulation and antireflux surgery for treatment of Barrett's esophagus.

Columnar-lined epithelium with specialized intestinal metaplasia of the esophagus (i.e., Barrett's esophagus) is a premalignant condition caused by chronic gastroesophageal reflux disease. Progression of intestinal metaplasia may be avoided by antireflux surgery, whereas regeneration of esophageal mucosa could be achieved by endoscopic argon plasma coagulation (EAPC). The aim of this prospective study was to show the early results of a combination of EAPC and antireflux surgery. Thirty patients with Barrett's esophagus were treated between August 1996 and December 1999. Regeneration of esophageal mucosa was achieved with several sessions of EAPC under general anesthesia. All patients were receiving a double dose of proton pump inhibitors. Endoscopic follow-up was performed 6 to 8 weeks after the last session. Antireflux surgery (Nissen [n = 26] or Toupet [n = 4] fundoplication) followed complete regeneration of the squamous epithelium in the esophagus. One year after laparoscopic fundoplication and EAPC follow-up with endoscopy and quadrant biopsies of the esophagus, 24-hour pH monitoring and esophageal manometry were performed. All 30 patients showed complete regeneration of the squamous epithelium after a median of two sessions (range 1 to 7) of EAPC. Twenty-two patients underwent 1-year follow-up studies. All showed endoscopically an intact fundic wrap. Recurrence of a 1 cm segment of Barrett's epithelium without dysplasia was present in two patients, both of whom had recurrent acid reflux due to failure of their antireflux procedure. Our results indicate that the combination of EAPC and antireflux surgery is an effective treatment option in patients with Barrett's esophagus with gastroesophageal reflux disease. Long-term follow-up of this therapy is necessary to evaluate its effect on cancer risk in Barrett's esophagus.

Adult↗
PubMedDate not supplied

[Trauma exposure and post-traumatic stress disorder in intensive care unit personnel].

A questionnaire-study on work related trauma was conducted at 15 intensive care units. 144 examined female and male (17%) nurses provided information on the type and frequency of highly stressful job experiences, symptoms of posttraumatic stress disorder (PCL-C), depression (ADS-K) and cognitive-emotional coping style (FAPK 1.3). The study participants had an average age of 32 and an average job experience of 8 years. They reported an average of 38 traumatic job experiences in which they were confronted with seriously injured, mutilated and dying patients, corpses and their own anxiety and helplessness. 88% suffered from intrusive symptoms, 75%) from arousal symptoms; 41% had developed post-traumatic stress disorder (PTSD). Compared with less disturbed participants nurses with PTSD reported significantly more often on depressive symptoms and deficiencies in emotional competence.

Adult↗
PubMedDate not supplied

[Induction of arthritis in healthy knee joints after intra-articular injection of the proteolytic enzyme elastase - An experimental investigation in the rabbit].

AIM: Humoral aspects are being discussed in the initiation of arthritis. Therefore, the effects of the proteolytic enzyme elastase on the cartilage of knee joints in rabbits have been investigated. The enzyme was evaluated using activities comparable to those in post-traumatic knee joint hemarthrosis in humans. METHOD: Polymorphonuclear leukocyte elastase was injected into one of the knee joints of 10 rabbits. In 5 animals (first study group), joints were then immobilized with a cast for 6 weeks. In the other 5 (second study group), no immobilization was applied. In the first zero group (2 animals), 0.9 % NaCl was injected intra-articularly without immobilization, whereas in the second zero group (2 anmals) knees were immobilized for 6 weeks without prior injection. Thus, the effect of immobilization could be evaluated additionally. Joint specimens were then examined histologically and electron microscopically. RESULTS: There was clear evidence of elastase having severe destructive effects on cartilage regardless of additional joint-immobilization. In neither zero group was there prearthritic damage to the cartilage. CONCLUSION: To prevent the initiation of cartilage damage by humoral factors, early elimination of the pathological intra-articular effusion is necessary.

Animals↗
PubMedDate not supplied

[The effect of methotrexate pharmacokinetics and of leucovorin rescue on the prognosis of osteosarcoma].

A total of 129 high-dosage methotrexate therapies performed in 19 patients with osteosarcoma were retrospectively analyzed. Serum methotrexate peak concentrations were found to vary widely, both inter-individually as well as in the same patient. The measured MTX peak concentrations correlated closely with pharmacokinetic data such as area under the curve and total body clearance. No correlations were found between the serum MTX correlations and different times after methotrexate administration. Increase in leucovorin rescue or low MTX peak concentrations were associated with poor prognosis. High-dosage methotrexate therapies with leucovorin rescue need to be further optimized in accordance with biochemical knowledge of the mode of action and the individual pharmacokinetic data of methotrexate. Such optimization may be expected to improve the prognosis for osteosarcoma. Serum methotrexate concentrations should be determined not only 24, 48, and 72 hours after methotrexate administration, in order to avoid elevated toxicity of the therapy, but also at the start of methotrexate infusion, in order to influence MTX peak concentrations at an early stage if necessary. Measurement of L-leucovorin in serum will be necessary, to enable a restrictive leucovorin rescue to be performed safely.

Adolescent↗