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M Binder

Publications and source records attributed to M Binder.

At least 199 records · Page 11Linked to original sources
PubMed1990

The murine situs inversus viscerum (iv) gene responsible for visceral asymmetry is linked tightly to the Igh-C cluster on chromosome 12.

The iv gene controls left-right determination during murine organogenesis. To map this gene, we analyzed backcross progeny produced by mating (C57BL/6J X MEV/Ty)F1-iv/+heterozygotes to C57BL/6J-iv homozygotes. Hybridization of a murine ecotropic virus probe and several homeotic box gene probes coupled with analysis of dominant visible markers enabled us to exclude the iv locus from much of the mouse genome. Spurred by a recent report that mapped the iv gene to mouse chromosome 12 which was not excluded by our previous work, we used the polymerase chain reaction on our larger cohort to determine that the iv gene is indeed linked tightly to the Igh-C locus on this chromosome: we observed 0/156 recombinants between the iv and Igh-C loci. Combining data from the two studies demonstrates that the murine iv gene is close (1/201 recombinants) to the Igh-C cluster on chromosome 12.

Animals↗
PubMed1990

Immunogold staining of intermediate-sized filaments of the vimentin type in human skin: a postembedding immunoelectron microscopic study.

We have studied the localization of vimentin in normal human skin at the ultrastructural level using a monoclonal mouse anti-vimentin antibody and a postembedding immunogold-staining technique on thin sections of Lowicryl K4M embedded biopsies. Selective immunogold labeling of intermediate-sized filaments (IF) of epidermal Langerhans cells and melanocytes and of dermal fibroblasts was demonstrated. The IF of fibroblasts were more intensely stained than those of the epidermal dendritic cells; cell processes and dendrites of all three cell populations exhibited a greater number of IF and more pronounced immunogold-labeling than the perinuclear cytoplasm, relating IF of the vimentin type to dendrite formation and/or function. The method described is an appropriate tool for immunoelectron microscopic studies of IF of the vimentin type in situ.

Humans↗
PubMed1990

Ribonuclease H(70) is a component of the yeast nuclear scaffold.

We have used monospecific antibodies against three ribonuclease H enzymes of Saccharomyces cerevisiae to investigate their intracellular localization. Fractionation experiments, as well as immunocytochemical staining, revealed a predominantly cytoplasmic localization of the RNase H proteins of 42,000 and 70,000 Mr, whereas that of 55,000 Mr showed equal distribution between nuclei and cytoplasm. The nuclear moiety of ribonuclease H(70) was found to be a part of the yeast nuclear scaffold, as investigated by immunoblotting and antibody inhibition experiments. The 42,000 and 55,000 Mr enzymes, on the other hand, are not scaffold-associated. We conclude that RNase H(70) is part of the nuclear substructure of yeast that was previously found to maintain specific interactions with yeast chromosomal origins of replication (ARS elements).

Cell Nucleus↗
PubMed1989

Defective interferon-augmented natural killer cell activity in patients with metastatic malignant melanoma.

Unstimulated and interferon (IFN)-stimulated natural killer cell (NK) activity was investigated in patients with malignant melanoma prior to the removal of the primary melanoma (stage I disease) or in patients with melanoma metastases. Unstimulated as well as IFN-stimulated NK activities, directed against the primarily NK-sensitive K562 cell line, were found not to differ significantly from the NK activity of healthy control subjects. In contrast, IFN-stimulated NK activity directed against the primarily NK-insensitive Chang hepatoma and JY cell lines was significantly lower in patients with metastatic melanoma than in patients with non-metastatic disease (Chang hepatoma cell line: P less than 0.02; JY cell line: P less than 0.0017) and - in experiments using the JY cell line - than in healthy controls (P less than 0.01). Stage I melanoma patients did not differ in their IFN-induced NK activity from healthy control subjects using Chang hepatoma and JY cell lines. Finally, the IFN-induced increase in NK activity directed against primarily NK-insensitive target cell lines was significant in stage I melanoma patients and in healthy controls (P less than 0.01, respectively), but not in patients with metastatic melanoma (P greater than 0.5). We thus conclude that patients with metastatic malignant melanoma exhibited a defect in IFN-augmented NK activity directed against primarily NK-insensitive targets.

Adult↗
PubMed1989

Interaction of different strains of Entamoeba histolytica with target cells: characterization of electrophysiological and morphological features.

Two strains of Entamoeba histolytica with pathogenic zymodemes (SFL3, HK9), one strain with non-pathogenic zymodeme ("Bru") and one non-pathogenic Entamoeba sp. strain ("cold strain"), were investigated with respect to their interaction with target cells. Three test systems were used: 1) direct microscopical observation and qualitative as well as quantitative evaluation of contact and binding events with MDCK cells as targets, 2) kinetics of cytotoxic activity as measured by means of chromium release from 51Cr-labelled K562 cells, and 3) electrophysiological observations with freshly prepared mouse liver cells. We observed that the non-pathogenic cold strain interacted only shortly with target cells (statistical events, interaction type "I"), but did not induce morphological changes, chromium release or depolarization of targets. Non-pathogenic and avirulent strain "Bru" showed, apart from type "I"-binding, the ability to establish tight (type "II") and long-lasting contact (type "III") with targets, but again without cytotoxic effects. The pathogenic but avirulent strain HK9 tightly interacted (type "II") and sometimes long-lasting with target cells, but morphological changes and chromium release were of a moderate degree during the first 20 min, and depolarization was only a rare event. In contrast, strain SFL3 produced tight and long-lasting contacts (type "III" binding), leading to cell death in 83% (type "IV" interaction) within 20 min, substantial chromium release within 10 min and rapid depolarization ("electric collapse") of target cells.

Animals↗
PubMed1987

Streptococcus suis infections in Danish pigs and experimental infection with Streptococcus suis serotype 7.

During a two-year period, Streptococcus suis serotypes 1-8 were isolated from 108 pigs examined at the laboratory. S. suis serotypes 2 and 7 represented 75% of the isolates. S. suis serotype 7 was isolated more frequently than reported from other countries, and mostly from piglets less than 3 weeks of age. Experimental inoculation of 7-day-old piglets with S. suis serotype 7 provoked severe illness within a week in 6 out of 7 animals. By bacteriological and pathological examination it was found that S. suis serotype 7 was pathogenic to piglets, giving rise to septicemia with predilection for joints, serous membranes and meninges.

Animals↗
PubMed1987

In situ hybridization at the electron microscope level.

This tutorial paper will review radioactive and non-radioactive in situ hybridization (ISH) techniques at the electron microscope (EM) level; describe our efforts in comparison to those of other groups who recently have published in this field and discuss some potential future applications. Our contribution is the development of a non-radioactive, postembedding technique for the detection of transcripts on thin sections of Lowicryl K4M-embedded cells or tissues. Biotinylated probes were prepared by nick-translation. Signal detection was accomplished with anti-biotin antibody and protein A-gold complexes. Specific labeling was obtained over structures known to be the site of expression. Compared to EM autoradiography this technique offers advantages: rapid signal detection; superior morphological preservation and superior spatial resolution.

Animals↗
PubMed1986

In situ hybridization at the electron microscope level: localization of transcripts on ultrathin sections of Lowicryl K4M-embedded tissue using biotinylated probes and protein A-gold complexes.

A technique has been developed for localizing hybrids formed in situ on semi-thin and ultrathin sections of Lowicryl K4M-embedded tissue. Biotinylated dUTP (Bio-11-dUTP and/or Bio-16-dUTP) was incorporated into mitochondrial rDNA and small nuclear U1 probes by nick-translation. The probes were hybridized to sections of Drosophila ovaries and subsequently detected with an anti-biotin antibody and protein A-gold complex. On semi-thin sections, probe detection was achieved by amplification steps with anti-protein A antibody and protein A-gold with subsequent silver enhancement. At the electron microscope level, specific labeling was obtained over structures known to be the site of expression of the appropriate genes (i.e., either over mitochondria or over nuclei). The labeling pattern at the light microscope level (semi-thin sections) was consistent with that obtained at the electron microscope level. The described nonradioactive procedures for hybrid detection on Lowicryl K4M-embedded tissue sections offer several advantages: rapid signal detection: superior morphological preservation and spatial resolution; and signal-to-noise ratios equivalent to radiolabeling.

Animals↗
PubMed1985

N-Ethyl-17(R,S)-methyl-(6aR,10aR)-delta 8-tetrahydrocannabinol-18-oic amide. Brain pharmacokinetics in mice, triglyceride/phospholipid partitioning and generalization to the discriminative stimulus properties of delta 9-THC in rats.

The title compound, designed as a model for the affinity moiety of a cannabinoid affinity gel was synthesized in tritiated form (sp. act. 7.27 mCi/mmole). To validate the affinity approach to isolate the putative THC receptor, the properties of the amide were studied. Upon i.p. injection in mice the amide reaches peak brain levels of 0.13% of the total dose after 15 min. Following i.v. injection, maximal brain concentrations of 1.9% are observed at 5 min. Compared to delta 9-THC, which distributes almost equally between triglyceride and phospholipid phases (51:49) the amide exhibits a strong preference for phospholipids (5:95) that can be interpreted as high relative membrane affinity. In rats trained in a water maze to discriminate between i.p. injections of 3 mg/kg delta 9-THC (ED50 = 1.8 mg/kg) and its vehicle, the amide was generalized to the training drug, being five times less potent (ED50 = 8.7 mg/kg) than delta 9-THC. This demonstration of cannabis-like activity indicates that the amide retains affinity to the postulated receptor and justifies the choice for the affinity ligand.

Animals↗
PubMed1985

Generalization of the discriminative stimulus properties of delta 9-THC to delta 9(11)-THC in rats.

Rats were trained in a water maze to discriminate between IP injections of 3 mg/kg delta 9-tetrahydrocannabinol (delta 9-THC) and its vehicle. Both delta 8- and delta 9(11)-THC were generalized to the training drug. In contrast to our observations in rhesus monkeys, where delta 9(11)-THC is at least 100 times less potent than delta 9-THC, delta 9(11)-THC was found to be only seven times less potent in the rat. Relative potencies, expressed as the dosage at which 50% of the animals gave drug responses (ED50) were 1.8 mg/kg and 12.2 mg/kg for delta 9- and delta 9(11)-THC respectively. Twenty-four hours after receiving 7 X ED50 = 12 mg/kg delta 9-THC the tests showed intermediate results when conducted with the training dosage; 4 X ED50 = 50 mg/kg delta 9(11)-THC 48 h prior to the training dosage of 3 mg/kg delta 9-THC completely blocked drug-appropriate responses. Coinjection of ED50 dosages of delta 9- and delta 9(11)-THC led to 90% drug responses, demonstrating the additivity of the cannabis-like effect of both cannabinoids. Differences in the individual sensitivity of the rats to the tested cannabinoids were observed. Findings are interpreted in terms of the receptor mechanism for cannabis-like activity.

Animals↗
PubMed1985

The teratogenic effects of a bis(dichloroacetyl)diamine on hamster embryos. Aortic arch anomalies and the pathogenesis of the DiGeorge syndrome.

A study of the teratogenic effects of Fertilysin, a bis(dichloroacetyl)diamine, on hamster embryos was undertaken for a comparison of Fertilysin-induced malformations with the DiGeorge syndrome of human patients, a rare birth defect characterized by thymic and parathyroid gland agenesis, abnormal facies, and aortic arch malformations. In treated hamsters, malformations of the aortic arches were found to be consistently produced, and many of these anomalies could not be explained by conventional methods of analysis. A pathogenetic scheme to classify malformations of the aortic arch and great vessels is offered, including a revision of Celoria and Patton's classification of interrupted aortic arches. It is suggested that the DiGeorge syndrome is a syndrome of truncated pharyngeal arch development with two general forms: 1) agenesis of or incomplete development of the sixth pharyngeal arch with pulmonic circulation through the fifth arch; 2) agenesis of or incomplete development of the fifth and sixth pharyngeal arches with pulmonic circulation through the fourth arch. The third aortic arch may descend into the thorax under these circumstances.

Abnormalities, Drug-Induced↗
PubMed1984

Chlorinated hydrocarbons in adipose tissue of infants and toddlers: inventory and studies on their association with intake of mothers' milk.

Chlorinated hydrocarbon and polychlorinated biphenyl (PCB) concentrations were determined in adipose tissue from 34 infants, 14 children in the 2nd year of life, and 2 older children. The highest mean concentration detected during the first 2 years of life was for PCBs (0.67 ppm), followed by DDT (0.57 ppm), HCB (0.23 ppm), and HCH (0.15 ppm). Concentrations of HCB and PCB, which are especially characteristic of highly industrialised countries, were considerably higher in children of German mothers than in those of Turkish mothers. All single investigated values were lower than the mean values for adults in the Federal Republic of Germany, but many were still higher than mean concentrations for adults in other parts of the world. A breakdown into children with high mothers' milk intake and those with low intake showed a highly significant association with the quantity of mothers' milk consumed: the concentration of organohalogens in adipose tissue of children with high intake was significantly higher than in those with low intake. Two tasks urgently demand our attention: the development of further ways to reduce environmental sources of organohalogen contamination and the study of the possible pathogenetic effect of these organohalogens on the health of our children.

Adipose Tissue↗
PubMed1984

Oestradiol-BSA conjugates for receptor histochemistry: problems of stability and interactions with cytosol.

The validity of histochemical methods for the localization of hormone receptors based on the binding of fluorescent bovine serum albumin conjugates of oestradiol was examined with respect to their stability and their interactions with the oestrogen receptor type I. Stability was assessed by measuring free oestrogen in conjugates by radioimmunoassay and/or receptor protein binding assay. Sufficient free oestrogen--in order to saturate type I and type II binding sites (ER I, ER II)--was detected in freshly prepared conjugates. This free oestrogen originates in inadequate removal of adsorptively bound original ligand after synthesis. Apart from this fact, conjugates appeared to be unstable in aqueous solutions, especially under the conditions used for for histochemical methods. Free oestrogen extracted from the conjugates was subjected to high performance liquid chromatography. Amongst the eluted peaks, oestradiol and/or the original ligand used for synthesis were identified. The in vitro interaction of conjugates with oestrogen receptors was studied by competitive binding analysis and by incubation of cytosol with a Sepharose-bound conjugate. The results, especially those concerning the amount of free oestrogen, suggest that neither ER I nor ER II is involved in the staining mechanism of conjugates.

Animals↗
PubMed1984

Type I estrogen receptors cannot be histochemically localized in frozen tissue sections using estradiol-albumin-FITC conjugates.

Only few investigators still report in literature that estradiol type I receptors can be histochemically visualized using estradiol-albumin-FITC conjugates (E2-BSA-FITC). Most of them report that it is not likely that fluorescence is due to conjugate--type I receptor interaction. It is assumed that rather type II receptors are involved. In this study clear evidence is presented that type I receptors are not visualized. There is some indication that specific staining is only obtained when type II binding sites are present.

Animals↗