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S Franke

Publications and source records attributed to S Franke.

At least 37 records · Page 2Linked to original sources
PubMed2002

[Endovascular therapy in combination with conventional vascular surgery for the treatment of peripheral arterial obliterative disease].

INTRODUCTION: In a prospective trial we analysed the results and the management of complications following a combined endovascular and vascular surgical therapy of peripheral occlusive arterial disease (POAD). PATIENTS AND METHODS: From November 1998 until January 2001 a total number of 61 patients with 64 extremities were included in this study. By preoperative angiography 19 patients had stenoses at three levels, 42 patients suffered from stenoses at two levels. The iliac axis was recanalized by intraluminal angioplasty (ITA) plus stent placement under general anesthesia. Simultaneously an infrainguinal bypass reconstruction and a local thrombendarterectomy (TEA) rsp. were performed. Intra- and postoperative complications and the patency rates as assessed by colour doppler ultrasound and angiography were analysed. RESULTS: The rate of conversion from endovascular to conventional surgery was 12.5 %. In 56 cases the endovascular therapy of the iliac axis was successful. In 28 patients a distal bypass was implanted, in 25 patients a local TEA was performed. Intraoperatively 6 dissections (10.7 %) were noted, dislocation of stents were seen in 4 patients (7.1 %), perforations occurred in 2 patients (3.6 %). Both perforations and 5/6 dissections were detected intraoperatively and were treated by endovascular means without complications. The early postoperative patency rate was 98.2 %, the secondary patency rate was 100 % and the cumulative patency rate after two years was 98.2 %. DISCUSSION: ITA and stent placement in the iliac axis can be established quickly and safely by the vascular surgeon. Intraoperative complications can be managed by endovascular means in most cases. Stent dislocation is avoidable in most cases. The complication rate after such combined endovascular therapy and conventional vascular surgery is determined by the surgical but not the endovascular part. Excellent early results and low complication rates lead to the conclusion that endovascular therapy in combination with conventional vascular surgery seems to be a reasonable supplement to the therapeutic options for the treatment of POAD.

Aged↗
PubMed2002

Are advanced glycation end-product-modified proteins of pathogenetic importance in fibromyalgia?

OBJECTIVE: To quantify the serum levels of the advanced glycation end-product (AGE) pentosidine in 41 patients with fibromyalgia (FM) and 46 healthy controls. The formation of pentosidine is closely related to oxidative stress. METHODS: Pentosidine was measured by reverse-phased high-performance liquid chromatography with gradient separation on a RP-18 column. RESULTS: Patients with FM have significantly higher pentosidine serum levels than healthy subjects. CONCLUSION: AGE modification of proteins leads to reduced solubility and high resistance to proteolytic digestion of such altered proteins (e.g. AGE-modified collagens). AGEs are also able to stimulate different kinds of cells via activation of the NFkappaB, mediated by specific receptors of AGEs (e.g. RAGE) on the cell surface. Both mechanisms may contribute to the development, perpetuation and spreading of pain phenomena in FM patients.

Adult↗
PubMed2002

Identification of the advanced glycation end products N(epsilon)-carboxymethyllysine in the synovial tissue of patients with rheumatoid arthritis.

BACKGROUND: Generation of advanced glycation end products (AGEs) is an inevitable process in vivo and can be accelerated under pathological conditions such as oxidative stress. In serum and synovial fluid of patients with rheumatoid arthritis (RA) raised AGE levels have been found. OBJECTIVE: To determine the presence of N(epsilon)-carboxymethyllysine (CML; marker of oxidative stress) in RA synovial tissue by immunohistology. METHODS: Frozen synovial tissue samples from 10 patients with RA and eight controls (four patients without joint disease and four patients with osteoarthritis (OA)) were treated with rabbit-anti-CML-IgG and goat-antirabbit-IgG. Immunostaining was visualised by streptavidine-alkaline phosphatase (chromogen fuchsin). Cell differentiation was performed with antibodies against CD68, CD45RO, and CD20. RESULTS: CML was detected in the synovial lining, sublining, and endothelium in 10/10 RA and 4/4 OA synovial specimens. In RA some macrophages (CD68+) and T cells (CD45RO+) showed positive immunostaining for CML, whereas B cells were negative. Staining in OA synovial sublining was weak compared with RA. CONCLUSIONS: CML was detected for the first time in RA and OA synovial tissue. Different patterns of immunostaining in RA and OA and the presence of CML on macrophages and T cells, suggest a role for CML in the pathogenesis of RA. This might be due to presentation of new epitopes which can maintain or even trigger an autoimmune response.

Adult↗
PubMed2001

Halogenated organic contaminants in sediments of the Havel and Spree rivers (Germany). Part 5 of organic compounds as contaminants of the Elbe river and its tributaries.

To give a detailed and comprehensive view on the state of pollution of the Havel and Spree rivers nontarget screening as well as quantitative (target) analyses were applied to anoxic sedimentsamples. Based on nontarget GC/MS analysis a significant contribution to the anthropogenic contamination could be attributed to halogenated compounds. Three groups of contaminants corresponding either to diffuse or local contamination could be distinguished. Several commonly observable compounds including pentachloroanisol, polychlorinated biphenyles, 2,4-dichlorobenzoic acid, and chlorinated benzenes were detected with a distribution reflecting the contribution of nonpoint source emissions. A second group of chlorinated as well as brominated compounds was attributed to a strong point source emission at the Teltow Canal. At the sampling locations influenced by this point source the amount of mono- and dibrominated naphthalenes, chlorinated naphthalenes, and hexachlorocyclohexanes as well as DDT- and methoxychlor-related compounds increased significantly as compared to the background concentrations. A third group of halogen compounds emitted at this site consisted of the pesticides bromopropylate, methoxychlor, and chlorfensone as well as specific brominated aromatics including 2,4,6-tribromoaniline, 4,4'-dibromobenzophenone, and brominated benzenes. In addition, tetrabromochlorotoluenes, tribromodichlorotoluenes, dibromotrichlorotoluenes, and 2,2-bis(4-bromophenyl)acetic acid isopropyl ester were identified and are reported for the first time as environmental contaminants. The amounts of brominated compounds detected in Teltow Canal sediments occurred at a similar concentration level as their chlorinated analogues. Therefore, investigations on the occurrence of such a broad spectrum of brominated compounds as established in this work are presumably required more frequently to assess the environmental impact of this type of emissions.

DDT↗
PubMed2001

Functional characterization of sphingolipid C4-hydroxylase genes from Arabidopsis thaliana.

In the genome of Arabidopsis thaliana, two genes were identified encoding isoenzymes for C4-hydroxylation of long chain bases (LCB) in plant sphingolipids. Both predicted proteins consist of 258 amino acid residues (77% identity) which show sequence similarity to di-iron-binding enzymes, such as Sur2p and Erg3p from yeast, involved in oxygen-dependent lipid modifications. Heterologous expression of these genes in a yeast sur2Delta-null mutant lacking C4-LCB hydroxylation resulted in the formation of D-ribo-C(18)- and -C(20)-phytosphinganine. The identity and stereochemical configuration of the isolated trihydroxybases was confirmed by electrospray ionization-mass spectroscopy, gas-liquid chromatography-mass spectrometry and 1H-nuclear magnetic resonance spectroscopy. These results represent the first functional identification of SUR2 genes from plants as well as from any organism other than yeast.

Arabidopsis↗
PubMed2001

Lymphocyte predominance Hodgkin disease is characterized by recurrent genomic imbalances.

Single-cell polymerase chain reaction (PCR) has been used as a tool to demonstrate clonality and B-cell origin of Reed-Sternberg (RS) cells in Hodgkin disease (HD). An analogous approach was used to investigate genomic imbalances in a (cyto)genetically poorly characterized subentity: lymphocyte predominance Hodgkin disease (LPHD). Nineteen cases of LPHD were selected for a comparative genomic hybridization (CGH) study. CGH was performed with degenerate oligonucleotide primed-PCR (DOP-PCR)-amplified DNA from 4-5 microdissected CD20+ malignant cells. All analyzed cases revealed a high number of genomic imbalances (average 10.8 per case), involving all chromosomes but the excluded 19, 22, and Y, indicating a high complexity of LPHD. The majority of detected aberrations were recurrent. Gain of 1, 2q, 3, 4q, 5q, 6, 8q, 11q, 12q, and X, and loss of chromosome 17 were identified in 36.8% to 68.4% of the analyzed cases. Some of them have also been found in non-Hodgkin lymphoma (NHL), and possibly represent secondary changes associated with disease progression. Gain of 2q, 4q, 5q, 6, 11q, however, are much more rarely observed in NHL and could be more specifically associated with LPHD. Particularly interesting is a frequent overrepresentation of chromosome arm 6q, a region usually deleted in NHL. Rearrangement of the BCL6 gene (3q27) demonstrated by cytogenetics and fluorescence in situ hybridization in 2 cases in this study suggests its contribution in pathogenesis of LPHD. In conclusion, the data show a consistent occurrence of genomic alterations in LPHD and highlight genomic regions that might be relevant for development and/or progression of this lymphoma entity.

Adult↗
PubMed2001

Secretion of cytokines by uroepithelial cells stimulated by Escherichia coli and Citrobacter spp.

Urinary tract epithelial cells (T 24/83) are able to express interleukin (IL)-6, IL-8, platelet-derived growth factor (PDGF) and tumour necrosis factor-alpha, but not IL-1 beta, IL-2, IL-4 and IL-10 in response to an infection with uropathogenic bacteria. The process of cytokine secretion is time dependent, with a significant increase in the cytokine activity after 60 min. The expression of virulence factors of the bacteria does not seem to play a role. The interaction between bacterial products (e.g. lipopolysaccharide) and/or bacterial adhesion mediated by adhesins and specific receptor molecules of cell surfaces may be responsible for the activity of mediator protein expression in the epithelial cells. The release of PDGF and IL-8 was found to be higher when due to Escherichia coli HB 101 (rough form) than that caused by other bacterial strains. Citrobacter CB 3009 provoked the highest level of IL-6. The PDGF level correlated significantly with IL-6 and IL-8 values (P<0.001). There was a significant correlation between the time-dependent release of IL-6 and IL-8 (P<0.05). In epithelial cytokine response to bacterial infection, the reaction of the epithelial cells may modify themselves (e.g. internalization of bacteria) and the immuno-regulatory processes that are caused by infection and responsible for parenchymal injury.

Citrobacter↗
PubMed2001

[Embolization of aneurysma spurium of the superior gluteal artery].

While for the surgical treatment there are the transgluteal and the retroperitoneal approach, the alternative radiological modality is less invasive. It is performed by a from contralateral placed guidant-catheter in combination with a tracker catheter with the possibility of transcatheter embolization with liquid, particles or coils. The rate of success is high, complications are seldom and the hospital stay is short. Both modalities can and should be used complementary. In the case of an intractable acute hemorrhage transcatheter embolization should be used firstly.

Aged↗
PubMed2001

Differences in the modulating potential of advanced glycation end product (AGE) peptides versus AGE proteins.

Differences in the modulating potential of advanced glycation end product (AGE) peptides versus AGE proteins. Advanced glycation end products (AGEs), identified as irreversible products of a complex reaction of carbonyl groups of reducing sugars with free protein amino groups, are characterized by resistance to proteolytic degradation. The incomplete digestion of AGEs results in low molecular weight AGEs accumulating in the blood of diabetic and uremic patients. We hypothesized that the accumulation of these compounds may contribute to the dysfunction and/or degeneration of tubular epithelial cells. Our study examined whether low-molecular-weight AGE peptides and high-molecular-weight AGE proteins affect the functional cellular properties of two tubular epithelial cell lines: immortalized human kidney tubular epithelial (IHKE) and immortalized rat renal proximal tubular cells (IRPTCs). Parameters of cellular damage and growth behavior were cell counting, analysis of the cellular metabolic activity (MTT assay), as well as cellular proliferation (3[H]-thymidine-incorporation). IHKE treated with bovine serum albumin-AGE (BSA-AGE 50) or BSA-AGE-Pep 50 revealed a decrease in cellular metabolic activity as compared with controls after 48 hours of incubation (73 +/- 9% for BSA-AGE 50 and 62 +/- 11% for BSA-AGE-Pep 50 vs. 89 +/- 8% for BSA Co 50). Low molecular weight BSA-AGE-Pep 50 induced a significantly greater cellular damage in IRPTCs as compared with high molecular weight BSA-AGE 50 after 144 hours of incubation (59 +/- 15% for BSA-AGE 50 vs. 31 +/- 13% for BSA-AGE-Pep 50). The decrease in metabolic activity correlated well with a decrease in cellular proliferation. The results suggest a higher toxic potential of low molecular weight AGE peptides compared with high molecular weight AGE proteins in IRPTC and IHKE. This may provide evidence that low molecular weight degradation products of AGE-modified proteins have an important risk potential.

Animals↗
PubMed2001

Influence of dialysis modalities on serum AGE levels in end-stage renal disease patients.

BACKGROUND: The accumulation of advanced glycation end-products (AGEs) in end-stage renal disease (ESRD) influenced by dialysis modalities is of current interest. Highly permeable membranes in haemodialysis or haemofiltration should be able to eliminate circulating AGEs as well as their AGE precursors more efficiently. METHODS: In our study, 10 non-diabetic and 10 diabetic ESRD patients were on haemodialysis with low-flux membranes (LF) followed by a cross-over haemodialysis with high-flux or super-flux polysulfone membranes (HF, SF) for 6 months each. We measured the protein-bound pentosidine and free pentosidine serum levels by high-performance liquid chromatography (HPLC) as well as the serum AGE peptide, AGE-beta(2)-microglobulin and beta(2)-microglobulin concentrations, using ELISA assays. RESULTS: All parameters investigated were significantly higher in dialysis patients than in healthy subjects. The reduction rates during a single dialysis session were found to be higher using the SF than those obtained with the HF (free pentosidine 82.4+/-7.3 vs 76.6+/- 8.7%; AGE peptides 79.7+/-7.7 vs 62.3+/-14.7%; AGE-beta(2)-microglobulin 64.0+/-16.5 vs 45.4+/-17.7%; beta(2)-microglobulin 70.5+/-5.6 vs 58.2+/-6.0%). The protein-bound pentosidine levels remained constant over the respective dialysis sessions. In the 6-month treatment period with the SF, decreased pre-dialysis serum levels of protein-bound pentosidine, free pentosidine and AGE peptides were observed in non-diabetics and diabetics as compared with values obtained with the LF. The respective pre-dialysis AGE-beta(2)-microglobulin concentrations decreased insignificantly, whereas those of beta(2)-microglobulin were significantly lower. Using the HF dialyser, only moderate changes of the parameters measured were noted. CONCLUSION: Treatment with the biocompatible polysulfone SF dialyser seems to be better suited to lower serum AGE levels and to eliminate their precursors.

Adult↗
PubMed2001

The AIDA autotransporter system is associated with F18 and stx2e in Escherichia coli isolates from pigs diagnosed with edema disease and postweaning diarrhea.

Pathogenic Escherichia coli strains are known to cause edema disease (ED) and postweaning diarrhea (PWD) in piglets. Although the exact mechanisms of pathogenicity that lead to ED-PWD remain to be elucidated, E. coli-borne Shiga-like toxin and adhesion-mediating virulence factors such as F18 adhesin or F4 fimbriae are believed to play a central role in ED-PWD. In light of these observations we investigated whether another E. coli adhesin, the plasmid-encoded AIDA (adhesin involved in diffuse adherence) might also be present in ED-PWD-causing E. coli isolates. For rapid screening for the AIDA system in large numbers of isolates, a multiplex PCR method along with a duplex Western blot procedure was developed. When screening 104 strains obtained from pigs with or without ED-PWD, we observed a high prevalence of the AIDA operon in porcine E. coli isolates, with over 25% of all strains being AIDA positive, and we could demonstrate a significant association of the intact AIDA gene (orfB) with ED-PWD, while defects in orfB were associated with the absence of disease. Although our data hint toward a contribution of AIDA to ED-PWD, further studies will be necessary since the presence of the AIDA genes was also associated with the presence of the Shiga-like toxin and F18 adhesin genes, two reported virulence factors for ED-PWD.

Adhesins, Escherichia coli↗
PubMed2001

In vitro-prepared advanced glycation end-products and the modulating potential of their low-molecular weight degradation products in IRPTC-A rat proximal-tubular derived kidney epithelial cell line.

Low-molecular advanced glycation end-products (AGEs)-degradation products resulting from a proteolysis of tissue or circulating AGEs represent up to 80% of AGE plasma immunoreactivity. These AGE peptides contribute to the dramatic increase in AGE levels in end-stage renal disease even in the absence of diabetes. Because glomerular filtered AGE-degradation products may accumulate within intracellular compartments of proximal tubular epithelial cells, we investigated whether there is a pathway potentially mediating damaging effects of AGE-degradation products by perturbation of the function of the tubuloepithelium. Proximal tubular-derived rat kidney cells (IRPTC) were incubated with high-molecular AGEs highly modified by incubation of bovine serum albumin (BSA) with glucose for 50 days in vitro, and with low-molecular AGE-degradation products derived from proteolytic cleavage and isolated in the molecular range between 1 and 30 kDa. The proliferation of IRPTC (3H-thymidine incorporation) was reduced to 89+/-1% and 69+/-2% after 24 hr of incubation with BSA-AGE and BSA-AGE-degradation products, respectively. The cell viability of IRPTC was reduced significantly to 59+/-15% and 31+/-13% after 144 hr of incubation with BSA-AGE and BSA-AGE-degradation products, respectively. Conditioned media obtained from IRPTC incubated for 72 hr with BSA-AGE and its degradation products increased the proliferation rate of renal fibroblasts (RFb) to 222+/-24% and 449+/-40%, respectively. Incubation of IRPTC with BSA-AGE-degradation products increased the expression of endothelin-1 (ET-1) mRNA to 210% after 1 hr; the expression of platelet-derived growth factor-B (PDGF-B) mRNA reached 184% after 2 hr. Regarding the toxicity of AGEs to the kidney, low-molecular weight AGE-degradation products possibly form an individual fraction with a comparatively higher toxic potential.

Animals↗
PubMed2000

Cell transformation and genotoxicity induced by bis(2, 3-dichloro-1-propyl) ether.

Bis(dichloropropyl) ether isomers have been identified in a petrochemical plant effluent through a toxicity identification evaluation study in the United States. They have also been observed in the microgram per liter range along one of the largest rivers in Europe, the Elbe River. In the present investigation, the genotoxic and transforming activity of a bis(dichloropropyl) ether isomer, bis(2,3-dichloro-1-propyl) ether, was assayed in vitro. The results demonstrate that bis(2,3-dichloro-1-propyl) ether is a potent mutagen in Salmonella typhimurium strains TA 100, TA 1535, and to a lesser extent in strain TA 98, but only when tested in the presence of a metabolic activation system (S9 mix). We have also investigated the induction of micronuclei by bis(2,3-dichloro-1-propyl) ether in the metabolically competent cell line, MCL-5. A linear, dose-dependent increase in micronuclei was observed following exposure to bis(2,3-dichloro-1-propyl) ether. The DNA strand-breaking capacity of this chemical was assessed in the alkaline single-cell gel electrophoresis ("comet") assay with MCL-5 cells. Bis(2,3-dichloro-1-propyl) ether clearly induced DNA strand breaks in the 4.5-45.5 microg/ml dose range. The ether also induced malignant transformation in C3H/M2 mouse fibroblasts after metabolic activation (S9 mix). Thus, it must be suspected that bis(2, 3-dichloro-1-propyl) ether may possess a carcinogenic potential. Since the compound along with its isomers is present in considerable concentrations in surface water, their elimination is a matter of significant public concern.

Animals↗
PubMed2000

Task-related variation of postpharyngeal and cuticular hydrocarbon compositions in the ant Myrmicaria eumenoides.

In the ant Myrmicaria eumenoides we investigated postpharyngeal and cuticular hydrocarbons. At eclosion the glands contained almost no hydrocarbons and there were no lipid inclusions in the glandular epithelium. During the first 3 weeks of adult life the amount of hydrocarbons in the gland increased until day 5, and then remained constant while the lipid content in the epithelium increased steadily. Intracolonial hydrocarbon compositions were not uniform. Compositions of post-pharyngeal and cuticular hydrocarbons in individual ants varied simultaneously, but in different manner depending on the tasks of the ant (brood-tenders, foragers, scouts). Variations on the cuticle were greater than in the gland, but they were strongly correlated. Independent of ants' age and task, cuticular hydrocarbon compositions were dominated by alkenes and alkadienes. Task-specific differences in cuticular compositions were mainly in the amount of alkenes (high in foragers) and alkadienes (high in brood-tenders). Variation of hydrocarbons was low in ants up to 10 weeks old. Thereafter, ants fell into two groups: (1) ants that did not change their hydrocarbons and remained in the nest, and (2) ants that changed their hydrocarbon compositions and became foragers. These results contribute to an ongoing discussion of the dynamic relationship between post-pharyngeal and cuticular hydrocarbons.

Age Factors↗
PubMed2000

Immunochemical detection of imidazolone in uremia and rheumatoid arthritis.

The advanced glycation end-product imidazolone is formed by reaction of arginine with 3-deoxyglucosone (3-DG), a reactive intermediate of the Maillard reaction, whose formation is non-oxidative. Using an antibody specific to this 3-DG-derived AGE, we demonstrated the presence of imidazolone-modified proteins in vivo in the urine and dialysate of patients with chronic renal failure, in the synovial fluid of patients with rheumatoid arthritis, as well as in vitro in human serum and human serum albumin incubated with glucose. Furthermore, we could show that in uremic patients the dimeric form of beta(2)-microglobulin is more susceptible to imidazolone modification than the monomeric one. Thus, the immunochemical detection of imidazolone may be a good marker for 3-DG-derived AGE modification in vivo and in vitro permitting a differentiation between the oxidative and the non-oxidative pathway of AGE generation.

Adult↗