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C Bachmeyer

Publications and source records attributed to C Bachmeyer.

At least 73 records · Page 4Linked to original sources
PubMed1999

Regulation by phosphorylation of the zinc finger protein KRC that binds the kappaB motif and V(D)J recombination signal sequences.

The DNA binding protein KRC (forkappaB binding andrecognitioncomponent of the V(D)J recombination signal sequence) belongs to a family of large zinc finger proteins that bind to the kappaB motif and contains two widely separated DNA binding structures. In addition to the kappaB motif, KRC fusion proteins bind to the signal sequences of V(D)J recombination to form highly ordered complexes. Here, we report that KRC may be regulated by post-translational modifications. Specific protein kinases present in the nucleus of pre-B cells phosphorylated a KRC fusion protein at tyrosine and serine residues. Such protein modifications increased DNA binding, thereby providing a mechanism by which KRC responds to signal transduction pathways. KRC is a substrate of epidermal growth factor receptor kinase and P34cdc2 kinase in vitro. Our results suggest that activation of the KRC family of transcription factors may provide a mechanism by which oncogenic tyrosine kinases regulate genes with kappaB-controlled gene regulatory elements.

Amino Acid Sequence↗
PubMed1999

In vivo and in vitro studies of major surface loop deletion mutants of the Escherichia coli K-12 maltoporin: contribution to maltose and maltooligosaccharide transport and binding.

The trimeric protein LamB of Escherichia coli K-12 (maltoporin) specifically facilitates the diffusion of maltose and maltooligosaccharides through the outer membrane. Each monomer consists of an 18-stranded antiparallel beta-barrel with nine surface loops (L1 to L9). The effects on transport and binding of the deletion of some of the surface loops or of combinations of several of them were studied in vivo and in vitro. In vivo, single-, DeltaL4, DeltaL5, DeltaL6, and double-loop deletions, DeltaL4 + DeltaL5 and DeltaL5 + DeltaL6, abolished maltoporin functions, but not the double deletion DeltaL4 + DeltaL6 and the triple deletion DeltaL4 + DeltaL5 + DeltaL6. While deletion of the central variable portion of loop L9 (DeltaL9v) affected maltoporin function only moderately, the combination of DeltaL9v with the double deletion of loops L4 and L6 (triple deletion DeltaL4 + DeltaL6 + DeltaL9v) strongly impaired maltoporin function and resulted in sensitivity to large hydrophilic antibiotics without change in channel size as measured in vitro. In vitro, the carbohydrate-binding properties of the different loop mutants were studied in titration experiments using the asymmetric and symmetric addition of the mutant porins and of the carbohydrates to one or both sides of the lipid bilayer membranes. The deletion of loop L9v alone (LamBDeltaL9v), of two loops L4 and L6 (LamBDeltaL4 + DeltaL6), of three loops L4, L5 and L6 (LamBDeltaL4 + DeltaL5 + DeltaL6) or of L4, L6 and L9v (LamBDeltaL4 + DeltaL6 + DeltaL9v) had relatively little influence on the carbohydrate-binding properties of the mutant channels, and they had approximately similar binding properties for carbohydrate addition to both sides compared with only one side. The deletion of one of the loops L4 (LamBDeltaL4) or L6 (LamBDeltaL6) resulted in an asymmetric carbohydrate binding. The in vivo and in vitro results, together with those of the purification across the starch column, suggest that maltooligosaccharides enter the LamB channel from the cell surface side with the non-reducing end in advance. The absence of some of the loops leads to obstruction of the channel from the outside, which results in a considerable difference in the on-rate of carbohydrate binding from the extracellular side compared with that from the periplasmic side.

Bacitracin↗
PubMed1999

Atrium and paroxetine-related severe hepatitis.

Two cases of severe hepatitis in young women using Atrium and paroxetine are presented. Both patients presented jaundice, marked increase in aminotransferases activities, and pronounced prolongation in prothrombin time. In both cases, liver biopsy specimen examination revealed lesions compatible with drug-related injury. Other causes of hepatic injury were reasonably ruled out by complete careful screening. Outcome was marked by rapid complete recovery in one case and by slow recovery in the other. We suggest that simultaneous treatment with Atrium and paroxetine could increase each of these drugs' hepatotoxicity.

Adult↗
PubMed1999

Subepidermal autoimmune bullous skin diseases associated with B-cell lymphoproliferative disorders.

The development of several types of autoimmune disorders is well known in the course of B-cell lymphoproliferative diseases. In order to investigate whether these autoimmune diseases may target cutaneous antigens, especially those of the dermal-epidermal junction, we conducted a retrospective analysis of all cutaneous direct immunofluorescence studies performed in patients with B-cell neoplasia who presented with cutaneous lesions requiring a skin biopsy. Patients with linear deposits of immunoglobulin or C3 molecules at the dermal-epidermal junction were studied further, using immunoblotting and immunoelectron microscopy. Patients with no overt hematologic malignancies but with cutaneous lesions requiring direct immunofluorescence were studied as a control population. During the study period, the diagnosis of autoimmune blistering diseases of the dermal-epidermal junction was established in 9/102 (8.9% +/- 2%) patients with a B-cell lymphoid disorder, compared with 288/8,189 (3.5% +/- 0.04%) patients without underlying hemopathy (p < 0.01). Among the 9 patients, 7 were studied in detail. Immunologic studies demonstrated epidermolysis bullosa acquisita in 6 patients and cicatricial pemphigoid in 1. Autoimmune blistering diseases, especially epidermolysis bullosa acquisita, are part of the spectrum of autoimmune disorders associated with B-cell neoplasia.

Aged↗
PubMed1998

[Lyme borreliosis: therapeutic aspects].

CAUSAL AGENTS: Several Borrelia burgdorferi sensu lato species have been recently described which cause different clinical forms of Lyme disease. B. garinii is implicated in neurological forms, B. burgdorferi sensu stricto in articular forms and B. afzelii in late cutaneous forms. As such disease diversity is seen only in Europe and Asia, clinical management in Europe is somewhat different than in North America. NUMEROUS CLINICAL TRIALS: A recently proposed classification of the European forms of Lyme disease is based on clinical presentation: contagious conditions or erythema migrans, early neurologic or cardiologic complications, late articular, neurologic or cutaneous complications. Therapeutic proposals should be guided by the results of European trials, taking into account this classification. ADAPTED MANAGEMENT: For contagious conditions or erythema migrans, amoxicillin and doxycycline are the first intention antibiotics and should be given for 14 to 21 days. Other antibiotic classes (macrolides, oral cephalosporins) have not been found be more effective and should be reserved for second line treatment. Early neurological involvement requires penicillin, a third generation cephalosporin or doxycycline for one month. Oral antibiotics are preferred in case of joint involvement using amoxicillin or doxycycline as first line therapy. A second regimen could be proposed in case of failure. Parenteral administration should be reserved for second line treatment. There is little data available on chronic atrophic acrodermatitis and protocols are based on ceftriaxone, doxycycline or penicillin.

Amoxicillin↗
PubMed1998

Muscular bacillary angiomatosis in AIDS.

We describe an unusual case of bacillary angiomatosis first misdiagnosed as Kaposi's sarcoma in muscle in a patient with HIV infection.

AIDS-Related Opportunistic Infections↗
PubMed1998

Acute autoimmune sensorineural hearing loss associated with Crohn's disease.

We report the sudden onset of bilateral hearing loss in a patient with Crohn's disease while the intestinal disease was quiescent. Antibodies directed against collagen type II were detected in the serum. Dramatic improvement of his hearing was observed under corticosteroid therapy. Diagnosis of autoimmune sensorineural hearing loss was established. This condition could be considered as an extraintestinal manifestation of Crohn's disease. Early diagnosis is mandated, as prompt and intensive treatment with corticosteroids and/or immunosuppressive drugs is effective and could prevent irreversible hearing loss.

Acute Disease↗
PubMed1997

Sphenoid sinus localization of multiple myeloma revealing evolution from benign gammopathy.

BACKGROUND: Plasma-cell neoplasms of the head and neck include extramedullary plasmacytoma and solitary plasmocytoma of bone or may represent a local manifestation of multiple myeloma. Involvement of sphenoid sinus has been rarely reported in multiple myeloma. METHODS: We present the case of a 77-year-old man with a 3-year-history of benign monoclonal IgG-lambda gammopathy who developed left sixth-nerve palsy and malaise. RESULTS: Computed tomography scan and magnetic resonance imaging scan disclosed a large soft-tissue mass of the sphenoid sinus with bone destruction. Sphenoid sinus biopsy revealed an IgG monoclonal plasma cell neoplasm. Diagnosis of multiple myeloma stage IA was then established. CONCLUSIONS: Diagnosis of plasma-cell neoplasm should be considered in sphenoid sinus tumors and depends upon histologic examination. This case enlightens the relationships between monoclonal benign gammopathy and plasma-cell neoplasms of the head and neck which constitute a continuum of B-cell lymphoproliferative disorders.

Aged↗
PubMed1997

Adie syndrome as the initial sign of primary Sjögren syndrome.

PURPOSE: To report Adie syndrome as the initial sign of primary Sjögren syndrome. METHODS: Case report. RESULTS: Adie syndrome was associated with necrotizing gingivitis and xerostomia. Antibodies against Ro (SS-A) were present. Prednisone and antimalarial drugs were ineffective in treating Adie syndrome but improved the necrotizing gingivitis. CONCLUSION: Search for Sjögren syndrome is mandated in patients with Adie syndrome. The latter condition is likely related to ganglionitis, a mechanism responsible for peripheral nervous system involvement in primary Sjögren syndrome.

Adie Syndrome↗