PubMed Health⌕ Search

Biomedical subjects

Josef Schröder

Publications and source records attributed to Josef Schröder.

6 recordsLinked to original sources
PubMed2006

5-Fluorouracil-related enhancement of adenoviral infection is Coxsackievirus-adenovirus receptor independent and associated with morphological changes in lipid membranes.

AIM: To evaluate the mechanism underlying the effects of 5-Fluorouracil (5-FU) on adenoviral infection. METHODS: Low and high Coxsackievirus-Adenovirus Receptor (CAR) expressing human colon carcinoma cell lines were treated with 5-FU and two E1-deleted adenoviral constructs, one transferring GFP (Ad/CMV-GFP) the other bax (Ad/CEA-bax). The number of infected cells were monitored by GFP expression. To evaluate the effects of 5-FU in a receptor free system, Ad/GFP were encapsulated in liposomes and treated with 5-FU. Ad/GFP release was estimated with PCR and infection of 293 cells with the supernatant. Electron microscopy of the Ad5-GFP-liposome complex was made to investigate morphological changes of the liposomes after 5-FU. RESULTS: Infection rates of all cell lines increased from 50% to 98% with emerging 5-FU concentrations. The enhanced viral uptake was independent of the CAR expression. Additionally, 5-FU treated liposomes released 2-2.5 times more adenoviruses. Furthermore, 5-FU-treated liposomes appeared irregular and porous-like. CONCLUSION: Adenoviral uptake is enhanced in the presence of 5-FU irrespective of CAR and is associated with morphological changes in membranes making the combination of both a promising option in gene therapy.

Adenoviridae Infections↗
PubMed2006

Dental resin materials in vivo - TEM results after one year: a pilot study.

Dental resins deteriorate clinically due to chewing forces, temperature changes, chemical agents or biological attack. Findings concerning these influences on the different components of a resin are limited. The aim of this study was to evaluate an alternative method for assessing the influence of the oral cavity on dental materials and their individual components as well as analyzing degradation effects over time. Seven dental composite and resin materials were inserted into the upper complete dentures of two subjects and evaluated after one year with a transmission electron microscope. The various resin components showed different degrees or deterioration. Composites with an urethandimethacrylate matrix were less vulnerable. A layer of salivary proteins (pellicle) was found on all materials but the polymethylmethacrylate reference. An accumulation of pellicle on filler particles and the crevice between filler and matrix was noted. We conclude that the tested method is effective for evaluating the interaction between the material's components and the biological environment. Further studies are needed to confirm these observations.

Administration, Oral↗
PubMed2005

Arthroscopic and histologic findings in Morquio's syndrome.

Mucopolysaccharidosis type IV A/B (Morquio's syndrome) is one of a heterogeneous group of lysosomal storage diseases characterized by accumulation of keratan sulfate in cells of connective tissue. From early childhood, the major orthopaedic manifestations are shortening of the trunk, spondylepiphyseal dysplasia, odontoid hypoplasia, upper cervical instability, lower-limb alignment problems, and degenerative joint disease. Most of the rare published case reports describe those characteristic clinical deformities of the skeleton. Our literature search showed that these striking arthroscopic findings have not been made public to date. We report a typical case of mucopolysaccharidosis type IV. We show and, in particular, correlate the arthroscopic with the histologic findings. In particular, the comparison between arthroscopy and light microscopy showed a remarkable extensive delamination of the chondral layer from subchondral bone of both knee joints. These findings should encourage further research, especially of the osteochondral borderline.

Adult↗
PubMed2002

Role of apoptosis in myocardial stunning after open heart surgery.

BACKGROUND: Myocardial preservation during open heart surgery is a subject of intense investigation. A prerequisite for further improvement is a better understanding of the underlying pathophysiologic mechanisms responsible for postoperative myocardial stunning. In this report, we analyzed the role of apoptosis in myocardial stunning. METHODS: Myocardial samples were obtained from 11 patients undergoing elective coronary artery bypass grafting before (control) and after cardioplegic arrest and reperfusion. Specimens were examined for apoptosis by electron microscopy, in situ end-labeling of DNA fragments, and biochemically for mitochondrial cytochrome c release. RESULTS: Electron microscopy revealed condensation and margination of nuclear chromatin after surgery, as well as swelling and membrane rupture in mitochondria of single myocytes surrounded by healthy cells. TUNEL-positive cells were also found. Cytochrome c release, an initial step in apoptosis, revealed a 3.4 +/- 0.4-fold increase during surgery (p < 0.0001). Furthermore, cytochrome c release from otherwise intact mitochondria showed a negative correlation with left ventricular function and a positive correlation with the duration of cardioplegic arrest and reperfusion (p < 0.05). CONCLUSIONS: Our data demonstrate that programmed cell death is evident early after open heart surgery and correlates with declining cardiac contractility. We conclude that apoptosis may be an important mechanism in postoperative myocardial stunning.

Apoptosis↗
PubMedDate not supplied

Cowpox and a cat.

Explore the source record for details and available documents.

Adolescent↗