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D Erdmann

Publications and source records attributed to D Erdmann.

At least 55 records · Page 3Linked to original sources
PubMed1996

Above-elbow arm replantation during pregnancy.

We report a successful replantation of an above-elbow amputated left arm in a 26-year-old female with a good, functional, long-term result. The patient was at 18 weeks estimated gestational age at the time of surgery. Major upper extremity replantation during pregnancy has not been previously described in the literature. Current operative and perioperative aspects, including considerations that favored microsurgical replantation in this unusual case, are discussed.

Adult↗
PubMed1996

Hyperbaric oxygen and cyclosporine as a combined treatment regimen to prevent skin allograft rejection in immunohistoincompatible mice.

Several previous studies reported various immunosuppressive effects of hyperbaric oxygen on nonspecific and specific cell-mediated reactions. A highly immunogenic skin allograft mouse model was used to evaluate the clinical relevance of the previously described immunosuppressive effects of hyperbaric oxygen. A 1.5 x 2.0-cm full-thickness skin allograft was cross-grafted between paired immunohistoincompatible mouse strains (N = 40, C57BL/6 and BALB/c female mice) that were randomly assigned to four groups receiving (1) no treatment (controls), (2) cyclosporine 1 mg per kilogram intraperitoneally daily, (3) cyclosporine plus a low-dose hyperbaric oxygen treatment (two treatments per day, once a week), and (4) cyclosporine plus a high-dose hyperbaric oxygen treatment (two treatments per day, three times a week) following surgery (N = 32). Allograft samples were taken from each group at day 9 after cross-grafting (N = 8). Skin allograft rejection was significantly delayed in all treatment groups compared to controls. No difference was found between animals who received cyclosporine only and the combined treatment regimen including low-dose hyperbaric oxygen. High-dose hyperbaric oxygen treatment in combination with cyclosporine substantially prolonged skin allograft survival compared to other treatments. These findings were histologically confirmed. We conclude that hyperbaric oxygen treatment as an adjunct to standard immunosuppressive therapy may only be advantageous if frequently applied.

Animals↗
PubMed1996

[Lymphocyte subpopulations in spleen and blood after early wound debridement and acute/chronic treatment with hyperbaric oxygen].

Thermal burns as well as hyperbaric oxygen (HBO) may cause immuno-suppression. This is one of the reasons why there is some controversy in the literature regarding adjuvant HBO treatment for thermal burn patient, despite the fact that HBO is known to decrease edema formation and possibly inhibits the progression from second to third degree burns. In this study, lymphocyte subpopulations were labelled with monoclonal antibodies W3/25 for helper cells, and OX-8 for cytotoxic/suppressor cells, to determine changes following early burn wound excision and acute or chronic HBO treatment in a 10% full-thickness burn model in rats. Lymphocyte subpopulations were extracted from blood and spleen on day 1, 8, and 15 following burn and/or treatment. W3/25 cells did not show any significant changes in blood or spleen over time. Significantly lower OX-8 cell counts were found in the group with burn + excision + chronic HBO treatment on day 8 and 15. Acute or chronic HBO treatment alone did not produce evidence of immuno-suppression.

Animals↗
PubMed1995

Orphan nuclear receptor HNF-4 binds to the human coagulation factor VII promoter.

The human coagulation protease factor VII plays a pivotal role in the initiation of the coagulation cascade by both the extrinsic and the intrinsic pathway. Although the gene, encoding factor VII, is expressed predominantly in the liver, the mechanisms underlying this tissue-specific expression have not been elucidated. In this study, we have analyzed the contribution of 5 kilobases upstream of the ATG translational initiation codon upon hepatic factor VII gene transcription. Transient transfection assays of a set of nested deletions in both liver and non-liver cell lines, HepG2 and HeLa respectively, indicate that several regions are involved in liver-specific expression. A slight negative effect on factor VII promoter activity in HepG2 cells is mediated by sequences upstream of position -1212. DNase I protection experiments reveal six footprints, FPVII1 through FPVII6, within the proximal 714 base pairs but a minimal promoter of 165 base pairs containing only FPVII3-6 is sufficient to confer liver-specific expression in HepG2 cells. Interestingly, FPVII6, at position -14 to +10 on the sense strand, would indicate that an as yet unknown transcription factor covers the ATG translational initiation codon. Gel retardation experiments show that the liver-enriched transcription factor HNF-4 binds specifically to footprint FPVII4 at position -71 to -49. Furthermore, a T --> A transversion, that in the HNF-4 binding site of factor IX causes a severe bleeding disorder, was introduced into the HNF-4-binding site of factor VII and reduced promoter activity by 20-50%. Coordinate HNF-4-mediated regulation of several blood protease genes as well as genes involved in lipid metabolism might account for the positive correlation of these factors with increased risk of occlusive heart diseases.

Amino Acid Sequence↗
PubMed1995

Organization and gene expression within restriction-modification systems of Herpetosiphon giganteus.

We have characterized a family of related restriction-modification (R-M) systems from the soil bacterium Herpetosiphon giganteus (Hgi). A comparison of their genetic organization reveals two types of regulatory proteins, called controlling ORF C. While one of these small reading frames derived from RM.HgiCI seems to be an enhancer of its own promoter, evidence is provided for a silencer function of the other ORF C derived from the closely related AvaII-type systems RM.HgiBI/CII/EI. The respective silencer function is detected during our various attempts to clone three isoschizomers with unusually high differences in their specific activity. Sequencing and site-directed mutagenesis revealed just two amino acids as being responsible for a massive increase in specific activity of these endonucleases.

Base Sequence↗
PubMed1995

Complications of 50 consecutive limited wrist fusions by a single surgeon.

Fifty limited wrist fusions were performed in 47 patients including 24 scaphoid-trapezium-trapezoid, 12 capitate-lunate-triquetrum-hamate, and 13 other limited wrist fusion combinations. Fusions were performed most commonly for rotary subluxation of the scaphoid and follow-up averaged 13.6 months for the chart review and 44 months for the questionnaire. There were 10 major complications in 8 patients, most of which required secondary surgery. There were 3 partial nonunions but no complete nonunions. Two patients later underwent a total wrist fusion. There were 15 minor complications in 10 patients, most of which were managed nonoperatively. A questionnaire was returned on 28 of the 50 fusions. Pain levels decreased from a preoperative level of 8.2 to a postoperative level of 3.0 (scale of 1-10 with 10 being most severe pain ever). All but 3 patients would have the fusion again.

Adult↗
PubMed1995

Skin allograft rejection and hyperbaric oxygen treatment in immune-histoincompatible mice.

The effect of hyperbaric oxygen (HBO) as an immunosuppressive agent was evaluated by using a highly immunogenic skin allograft mouse model. Immune-histoincompatible female C57BL/6 and BALB/c mice (N = 30) were randomly assigned to three groups receiving no treatment (control group), low dose HBO treatment (two treatments once a week), and intermediate HBO treatment (two treatments 3 times/wk) 1 wk before and 2 wk after transplantation of a 1.5 x 2 cm full thickness skin allograft from the back. Rejection was observed a Day 7 and was completed 14 days after surgery in controls. Low dose and intermediate HBO treatment delayed skin allograft rejection, which was histologically confirmed.

Animals↗
PubMed1994

[Ovarian suppression with Diane 35/50].

In this study, hormone profiles were studied using Diane 35 and Diane 50 before and after treatment for 4-25 months. A comparison of the hormone profiles with Diane 35 or Diane 50 should investigate, if both preparations induce complete ovarian suppression, independent of the given dose of ethinyl oestradiol. 43 patients were treated with Diane 35 and 15 women with Diane 50 over a different lengths of time--up to a period of 25 cycles. Parallel to the determination of the hormone profiles (luteinising hormone [LH], follicle stimulating hormone [FSH], prolactin, oestrone [E1], oestradiol [E2], progesterone, total testosterone [T. T.], free testosterone [F. T.], dehydroepiandrosterone-sulfate [DHEA-S], delta-4-androstenedione [A.] and sex hormone binding globulin [SHBG]), observations on the androgen symptoms before treatment and their course during therapy were made. Moreover, the ratios of LH/FSH and E1/E2 as well as the androgenic index, the ratio of total testosterone/SHBG were determined as control of treatment effects. The most important hormonal changes, which had been observed during a period up to two years are the following: --LH and FSH suppression--prolactin with increasing tendency--decrease of the total androgens and free testosterone-- decrease of the oestrogens E1, E2--increase of SHBG. The confirmation of the efficacy of the anti-androgen/oestrogen combination was reflected by the decline of the androgenic index in all groups. Acne and seborrhoe improved after 3-4 cycles; alopecia after 8-9 cycles and hirsutism diminished after 3 cycles of treatment. In spite of different doses of the combined preparations with 2 mg cyproteronacetate and 0.035 or 0.050 mg ethinyloestradiol, no difference in ovarian suppression as well clinical effects could be found.

Adult↗
PubMed1992

Metabolism of 3-methyldiphenyl ether by Sphingomonas sp. SS31.

The bacterium Sphingomonas sp. SS31, which was obtained from the diphenyl ether-degrading strain Sphingomonas sp. SS3 by an adaptation process, utilized 3-methyldiphenyl ether for growth in addition to diphenyl ether. The initial enzymatic attack onto this compound proceeded by a regioselective, but non-specific dioxygenation at the carbon carrying the ether bridge and the adjacent carbon of the unsubstituted as well as the methyl-substituted aromatic nucleus. Upon spontaneous decomposition, the resulting unstable hemiacetal structure yielded 3-methylphenol and catechol, or phenol, 3-methylcatechol, and 4-methylcatechol, respectively. Phenol and 3-methylphenol were oxidized to the corresponding catechols which, after subsequent ortho-cleavage, were channeled into the oxoadipate pathway.

Adaptation, Physiological↗
PubMed1992

Stepwise cloning and genetic organization of the seemingly unclonable HgiCII restriction-modification system from Herpetosiphon giganteus strain Hpg9, using PCR technique.

The genes, hgiCIIR and hgiCIIM, that encode the HgiCII restriction and modification (R-M) system from Herpetosiphon giganteus strain Hpg9, an AvaII isoschizomer recognizing the sequence, GGATCC, were cloned in Escherichia coli. Cloning the respective hgiCIIM gene was achieved via in vitro selection both from a Sau3AI- and an NheI-generated plasmid gene library using AvaII, a commercially available isoschizomer of HgiCII. However, all attempts to clone the closely linked hgiCIIR and M genes in a single step resulted in deletions spanning parts of the coding region of hgiCIIR. Therefore, cloning of the missing 3'-terminal part of this gene was achieved by applying the inverse polymerase-chain-reaction technique. All attempts to construct an enzymatically active R.HgiCII failed; only the inactivated hgiCIIR gene could be cloned. Sequencing of the hgiCIIRM region (carrying predesigned small mutations in the R gene) disclosed three open reading frames (ORFs): one small ORF preceding the methltransferase (MTase)-encoding gene, plus those encoding M.HgiCII (49,620 Da) and R.HgiCII (30,891 Da). M.HgiCII exhibits the common motif of ten conserved amino-acid blocks typically found within the group of m5C-MTases. The R-M system of HgiCII reveals strong homologies to the isoschizomeric R-M system of HgiBI from H. giganteus strain Hpg5, which, in contrast, could be cloned in one step.

Amino Acid Sequence↗
PubMed1992

Biodegradation of diphenyl ether and its monohalogenated derivatives by Sphingomonas sp. strain SS3.

The bacterium Sphingomonas sp. strain SS3, which utilizes diphenyl ether and its 4-fluoro, 4-chloro, and (to a considerably lesser extent) 4-bromo derivatives as sole sources of carbon and energy, was enriched from soil samples of an industrial waste deposit. The bacterium showed cometabolic activities toward all other isomeric monohalogenated diphenyl ethers. During diphenyl ether degradation in batch culture experiments, phenol and catechol were produced as intermediates which were then channeled into the 3-oxoadipate pathway. The initial step in the degradation follows the recently discovered mechanism of 1,2-dioxygenation, which yields unstable phenolic hemiacetals from diphenyl ether structures. Oxidation of the structure-related dibenzo-p-dioxin yielded 2-(2-hydroxyphenoxy)-muconate upon ortho cleavage of the intermediate 2,2',3-trihydroxydiphenyl ether. Formation of phenol, catechol, halophenol, and halocatechol from the conversion of monohalogenated diphenyl ethers gives evidence for a nonspecific attack of the dioxygenating enzyme system.

Adipates↗
PubMed1991

Cloning and molecular characterization of the HgiCI restriction/modification system from Herpetosiphon giganteus Hpg9 reveals high similarity to BanI.

The genes coding for the GGYRCC specific restriction/modification system HgiCI from Herpetosiphon giganteus Hpg9 have been cloned in Escherichia coli in three steps. As an initial step, the methyltransferase gene could be obtained after heterologous in vitro selection of a plasmid gene bank by cleavage with the isoschizomeric restriction endonuclease BanI. The adjacent endonuclease gene was cloned following Southern blot analysis of flanking genomic regions. The two genes code for polypeptides of 420 amino acids (M.HgiCI) and 345 amino acids (R.HgiCI). Establishing a functional endonuclease gene could only be achieved using a tightly regulated expression system or by methylation of the genomic DNA prior to transformation of the endonuclease gene. The methyltransferase M.HgiCI shows significant similarities to the family of 5-methylcytidine methyltransferases. Striking similarities could be found with both the isoschizomeric endonuclease and methyltransferase of the BanI restriction/modification system from Bacillus aneurinolyticus.

Amino Acid Sequence↗
PubMed1991

Isolation and genetic structure of the AvaII isoschizomeric restriction-modification system HgiBI from Herpetosiphon giganteus Hpg5: M.HgiBI reveals high homology to M.BanI.

The complete type II restriction-modification system HgiBI of Herpetosiphon giganteus strain Hpg5 recognizing the AvaII specific DNA sequence GGWCC has been cloned and expressed functionally active in Escherichia coli. A considerable acceleration in cloning could be achieved by preparing a size restricted library after application of a related hybridization probe. Both methyltransferase (437 codons) and restriction endonuclease gene (274 codons) were found to be encoded on a 3.6 kilobases ClaI/HincII fragment in the same transcriptional orientation separated by one triplett only. Protein sequence comparisons revealed a close resemblance of M.HgiBI to the group of m5C-methyltransferases, especially to M.BanI from Bacillus aneurinolyticus with the related recognition sequence GGYRCC. In contrast, no significant similarities have been observed for the associated endonuclease R.HgiBI with any other restriction enzyme described so far, even not with the isoschizomeric R.SinI from Salmonella infantis, or with R.BanI.

Amino Acid Sequence↗
PubMed1991

Stepwise cloning and molecular characterization of the HgiDI restriction-modification system from Herpetosiphon giganteus Hpa2.

The restriction-modification system HgiDI from Herpetosiphon giganteus strain Hpa2 has been cloned in E. coli in a two-step procedure. Selection of the methyltransferase (M.HgiDI) gene in vitro was performed using the heterologous restriction endonuclease AhaII, an isoschizomer of Acyl and HgiDI (GRCGYC). Cloning of the complete HgiDI endonuclease (R.HgiDI) gene could only be achieved in recipient cells harbouring a recombinant plasmid, which was expressing the corresponding methyltransferase and could thereby prevent the host from self-destruction of its genetic material. The HgiDI restriction-modification system was sequenced and functionally correlated with two open reading frames of 309 (M) and 359 (R) codons. In homology studies M.HgiDI showed significant similarities to 20 other m5C-methyltransferases and turned out to be the most compact enzyme of this group described so far. Initial attempts for overexpression of M.HgiDI and partial purification of R.HgiDI have been successful.

Amino Acid Sequence↗
PubMed1987

X-linked hypogammaglobulinaemia with a late secretion defect. A family study.

Three boy cousins suffering from x-linked hypogammaglobulinaemia have been described. Their disease is quite different from the classical x-linked hypogammaglobulinaemia. We present data from 15 family members of three families. The three mothers are sisters and 3 boys from 5 are suffering from immunodeficiency. HLA A, B and DR typing and in vitro diagnostics of immune functions of all family members were carried out. In the patients we could demonstrate a well functioning T cell system which seems to be regular for T cell help on PMW driven B cell maturation into cytoplasmic immunoglobulin positive (cIg+) cells of all immunoglobulin classes but we had no evidence for IgG secreting cells in a plaque forming cell (PFC) assay. The registration of spontaneous suppressor phenomena should be taken into account. If patients undergo an gamma-globulin therapy the changed suppressor effects come back to normal values but the secretion defect is unchanged. The three healthy mothers express one identical haplotype (A2 B8 DR3) which we could demonstrate in the three patients but also in one healthy boy.

Agammaglobulinemia↗
PubMed1985

[The PWM model of the immunoglobulin synthesis capacity of human peripheral blood lymphocytes. II. Modification of the immunofluorescent detection of cytoplasmic immunoglobulins (cIg+)].

To detect intracytoplasmic antibodies after PWM-stimulation of peripheral mononuclear cells we used class specific antisera against IgG, A and M and ascertained the whole number of cIg+-cells by addition. The number of cIg+-cells after culturing 7 days without mitogen was below 1%, with PWM-stimulation 14,7% +/- 8,5 (n = 29, blood donors). We discussed the requirements for the culture conditions and for the immunofluorescence detection.

Blood Donors↗
PubMed1984

[Operative ureterorenoscope for the use of ultrasound and calculus extraction].

Ureteroscopy is used not only to clarify tumorous processes in the area of the ureter but also for removal or ultrasonic destruction of distal ureteral stones. Instruments have been developed that allow application of an optically controlled ultrasonic or metal loop. With our instrument we removed distal ureteral stones in 12 cases applying ultrasound or a Dormia loop. The different techniques and strategies are presented. In animal experiments we investigated the effect of ultrasound on the urothelium. We found that short time application (less than 30 s) does not leave irreversible damages. Removal of ureteral stones by ureteroscopy is indicated in stones which do not pass spontaneously or after unsuccessful efforts to remove the stones by means of a Zeissloop that is in cases where hitherto the only way of action possible was to carry out an ureterolithotomy.

Adult↗