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D Günther

Publications and source records attributed to D Günther.

At least 37 records · Page 2Linked to original sources
PubMed1998

Neisseria gonorrhoeae porin modulates phagosome maturation.

The porin (PorB) of Neisseria gonorrhoeae has been implicated in the pathogenesis of this species. Porin is believed to translocate from the bacterial outer membrane into target cell membranes affecting various cell functions. Here we investigated the effect of porin on phagosome maturation. Phagocytosis of latex beads by human macrophages was allowed in the presence or absence of purified porin. Isolation of latex bead-containing phagosomes and subsequent two-dimensional gel electrophoresis revealed substantial differences in the phagosomal protein composition. Immunoblotting detected higher amounts of annexin II and the early endocytic markers Rab5 and transferrin receptor and decreased levels of the late endocytic markers Rab7 and cathepsin D in phagosomes obtained in the presence of porin compared with those obtained in its absence. Furthermore, association of Rab4 with the latex bead-containing phagosomes was revealed by flow cytometry. The amount of this small GTPase was markedly higher in the phagosomes isolated in the presence of porin. The data thus indicate that neisserial porin is itself able to arrest phagosome maturation within macrophages.

Bacterial Outer Membrane Proteins↗
PubMed1998

Crystallization and preliminary X-ray crystallographic studies of the 13-fold symmetric portal protein of bacteriophage SPP1.

Portal proteins are cyclical oligomers which play essential roles in bacteriophage pro-capsid formation, DNA packaging, and in connector formation. Bacteriophage SPP1 portal protein (gp6) is a turbine-like molecule with 13-fold symmetry [Dube et al. (1993) EMBO J. 12, 1303-1309]. The purified protein was crystallized with polyethylene glycol 400 as the precipitating agent using the vapor-diffusion method. Salt conditions were selected based on the properties of gp6 in different ionic environments. X-ray diffraction data up to a resolution of 7.85 A were measured from frozen crystals with orthorhombic space group C2221 and cell dimensions a = 180.5 (5), b = 223.5 (5), c = 417 (1) A. The asymmetric unit contains one tridecameric portal protein with 57.3 kDa subunits. The self-rotation searches confirm the 13-fold symmetry of the crystallized protein.

Capsid↗
PubMed1997

Head morphogenesis genes of the Bacillus subtilis bacteriophage SPP1.

We have identified and characterized the phage cistrons required for assembly of SPP1 heads. A DNA fragment containing most of the head morphogenesis genes was cloned and sequenced. The 3'-end of a previously identified gene (gene 6) and eight complete open reading frames (7 to 15) were predicted. We have assigned genes 7, 8, 9, 11, 12, 13, 14 and 15 to these orfs by correlating genetic and immunological data with DNA and protein sequence information. G7P was identified as a minor structural component of proheads and heads, G11P as the scaffold protein, G12P and G15P as head minor proteins and G13P as the coat protein. Characterization of intermediates in head assembly, which accumulate during infection with mutants deficient in DNA packaging or in morphogenetic genes, allowed the definition of the head assembly pathway. No proteolytic processing of any of the head components was detected. Removal of G11P by mutation leads to the accumulation of prohead-related structures and aberrant particles which are similar to the assemblies formed by purified G13P in the absence of other phage-encoded proteins. The native molecular masses of G11P and G13P are about 350 kDa and larger than 5000 kDa, respectively (predicted molecular masses 23.4 kDa and 35.3 kDa, respectively). G13P, upon denaturation and renaturation, assembles from protomers into some prohead-related structures. The organization of the DNA packaging and head genes of SPP1 resembles the organization of genes in the analogous regions of phage lambda and P22.

Amino Acid Sequence↗
PubMed1997

Concentrations of lysosomal cysteine proteases are decreased in renal cell carcinoma compared with normal kidney.

Renal cell carcinoma contains significantly lower concentrations of the lysosomal cysteine proteases, cathepsins B, C, H, L and S, than does normal kidney, as shown by several methods, such as activity determination, enzyme-linked immunosorbent assay, immunoblotting and immunohistochemistry. The same low levels of enzyme activity and concentration have been determined in renal cell carcinoma metastases in the lung. Our results on the decreased concentration of cysteine peptidases at the protein level would seem to conflict with earlier results on an increased concentration of the cathepsin L mRNA in renal cell carcinoma.

Carcinoma, Renal Cell↗
PubMed1997

Immunohistochemical and clinical evaluation of cathepsin expression in soft tissue sarcomas.

Lysosomal proteases are known to enhance the spread of epithelial tumour cells, but little is known of the possible role of proteases in the growth of soft tissue sarcomas (STS). We investigated the expression of cathepsins D, B, S, H, L and procathepsin L in frozen sections of 34 STS from 34 patients by immunohistochemistry (IHC). Cathepsins D, B and H were relatively highly expressed in STS (77-91%). The expression rate of cathepsins S and L and of procathepsin L was lower (40-66%). Cathepsin S and L expression showed a moderate (P = 0.078 and P = 0.019) and procathepsin L a strong (P = 0.00001) correlation with the survival rate of STS patients. Cathepsin S expression is also correlated with the local recurrence rate (P < 0.01). Lysosomal proteases may play a role in STS progression, and cathepsin expression may also have significance as a prognostic factor in STS.

Adult↗
PubMed1997

Monoclonal antibodies against cathepsin L and procathepsin L of different species.

Mouse monoclonal antibodies directed against cathepsin L and procathepsin L have been generated. Mice were immunized with human procathepsin L purified from the cell culture medium of human nonsmall cell lung cancer cell line EPLC 32 M1. More than 400 hybridoma clones were screened by ELISA or Western blot and 50 were found to secrete antibodies which reacted with cathepsin L or its precursor. Twenty-six clones were selected for further characterization of the antibodies according to their reactivity in ELISA, Western blot, and immunocytochemistry against the mature enzyme or its latent precursor of man, rat, or mouse. Only those antibodies are described here, which do not cross-react with the closely related cathepsins B and S or their latent proenzymes.

Animals↗
PubMed1996

Elemental fractionation in laser ablation inductively coupled plasma mass spectrometry.

The major challenge to the use of laser ablation sample introduction, combined with inductively coupled plasma mass spectrometry, is the problem of calibration. In the geological analysis of minerals, calibration is complicated by the extraordinarily wide variety of sample matrices which may be encountered. While there is a lack of mineral standards with well characterized concentrations near 1 microg/g, the NIST glass reference materials (SRM 610-617) have been demonstrated to be very useful for the analysis of a wide variety of lithophile elements in silicate samples. An internal reference element, for which the concentration is known in the sample, has been widely used to make corrections for the multiplicative effects of volume (or weight) of the sample ablated, instrument drift, and matrix effects. This procedure works extremely well where elements being determined and the internal reference element being used share similar ablation behaviours; i.e., they do not fractionate progressively during the ablation and transport process. In this study, it is demonstrated that, in terms of ablation behaviour, elements fall into several distinct clusters and that the elements within these clusters correlate well with each other during a period of ablation. Thus, elements within a cluster can be determined using an internal reference element from within the same cluster. While a combination of periodic varying properties typifies the clusters, the geochemical classification of elements into lithophile (silicate loving), and chalcophile (sulphide loving) appears to offer the best characterization of the major groups.

Journal Article↗
PubMed1994

Hybridoma cells producing antibodies to cathepsin L have greatly reduced potential for tumour growth.

Several tumour-forming cell lines are known to secrete the precursor of a lysosomal cysteine proteinase, procathepsin L. The function in tumour growth and proliferation of this neutral-pH-labile proteinase or its precursor outside lysosomes is as yet unknown. Murine myeloma cells (P3X63Ag8.653) secrete procathepsin L and exhibit a high potential for malignant tumour growth and metastasis. Such cells were fused with spleen cells of mice immunized with cathepsin L. Clones of the resulting hybridoma cells continued to secrete procathepsin L, but also secreted the antibody to cathepsin L. Here we show that the hybridoma cells producing an antibody to cathepsin L have, to a great extent, lost the potential that they otherwise exhibit for inducing solid tumours after implantation into mice.

Animals↗
PubMed1989

[Laser micro-spectroanalytical determinations of aluminum in lumbar vertebrae of non-nephrectomized and 5/6 nephrectomized rats after application of dose- and time-dependent aluminum chloride solutions].

In order to obtain further informations on the mode of action of Al, we carried out lasermicroanalytical determinations (LMA) of Aluminium (Al) on different parts of lumbar vertebrae in 54 non-nephrectomized rats and 54 ones 5/6 nephrectomized which were divided in 3 groups. The animals were treated with solutions of physiological NaCl in the control group (0.25 ml/100 g b.w.) and different Al-doses (0.05 and 0.5 mg/kg b.w.) intraperitoneally and daily for 4, 8, and 12 weeks. The results were compared with those of histochemical Al-detections by the method of IRWIN (1955). Lumbar vertebrae of the non-nephrectomized rats in the control group did not contain Al by LMA- and histochemical determination investigated in all the time intervals. Al-doses of 0.05 mg/100 g b.w. induced only a positive Al-proof 12 weeks after the beginning of the injections in the 5/6 nephrectomized animals by LMA, whereas Al-doses 10 times higher effected an Al-deposit of different concentration in the substance compact and substance spongioid of the lumbar body of vertebrae from the 4th week in the 5/6 nephrectomized and the 8th in the non-nephrectomized rats. The sensitiveness of the Al-detection by LMA was higher in comparison with the histochemical procedure, and an Al-accumulation in the lumbar vertebrae of the 5/6 nephrectomized rats is distinctly earlier than in those of non-nephrectomized animals.

Aluminum↗
PubMed1982

[Friedrich disease].

Explore the source record for details and available documents.

Diagnosis, Differential↗
PubMed1981

[Cervical dysphagia in scleroedema adultorum Buschke (author's transl)].

Scleroedema adultorum Buschke is characterized by progressive hardening of the skin. In contrast to scleroderma the hardening occurs in the skin of the trunk while extremities remain largely free. Internal organs are said not to be involved in scleroedema adultorum Buschke. The full picture of the persistent form of scleroedema adultorum Buschke was observed in two patients. One patient complained of increasing dysphagia with regurgitation and aspiration. Manometry and X-ray cinematographic investigation showed inappropriate relaxation of the upper oesophageal sphincter. In the other patient who had not previously had swallowed difficulties manometry showed achalasia of the upper oesophageal sphincter. The functional disturbances of the upper oesophagus indicate the possibility of an involvement of internal organs in scleroedema adultorum Buschke. However, proof of an aetiological connection between disturbances of oesophageal motility and skin disease requires systematic investigations in a larger group of patients.

Adult↗
PubMed1981

[Achalasia of the oesophagus; early and late results of dilatation and surgical procedures (author's transl)].

Till now etiology and pathogenesis of achalasia of the oesophagus are unknown. The disease is based on dysfunction of the lower oesophageal sphincter. Early and late results of dilatation and surgical procedures are compared. This review deals with 57 operated patients and 102 dilatated ones (Starck's Dilatator). Late results--25 operated and 22 dilatated patients were evaluated on an average at 9.5 or 8.3 years respectively. In the early stage of achalasia 2 to 3 dilatations are recommended. A cardio-myotomy combined witha fundoplication should be performed in high-graded stenoses and after unsuccessful dilatation.

Adolescent↗
PubMed1980

[The azygos vein lobe and its clinical significance (author's transl)].

The incidence and development on the azygos vein lobe are reviewed briefly. Examination of 10 000 radiographs of normal people showed that it occurred in 0,7% of cases. The clinical significance of the azygos vein lobe is discussed. In particular it may important in evaluating post-operative radiographs of patients in intensive care.

Azygos Vein↗