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R Schafer

Publications and source records attributed to R Schafer.

At least 37 records · Page 2Linked to original sources
PubMed1995

In the wake of Heinz Hartmann.

This study of Heinz Hartmann's contributions emphasises change within continuity. Specifically, it is argued that he both integrated and changed significantly Freud's structural theory--his 'ego psychology'. This he did through his then-modern concept of adaptation. In turn, adaptation paved the way towards further change in the direction of current emphases on dialogue and intersubjectivity. These new developments have contributed beneficially to theory and clinical practice, but, like all new developments, they have introduced new problems, among them unreflective and undisciplined eclecticism. Consideration is given to the incompleteness inherent in theory construction. In psychoanalysis, the new, object-related developments require as a complement some version of the type of structural theorising initiated by Freud and developed to its highest point by Hartmann and his close collaborators particularly; in meeting that requirement, some version of an objectivist stance is also required to complement the subjectivism and pluralism of the newer developments. Throughout this appreciation of Hartmann's role in the history of psychoanalytic thought, an effort is made to undo the negative effects of misreadings that took his ideas on adaptation and ego psychology to mean an endorsement of superficial adjustment or conformity and an overvaluation of conscious mental processes.

Ego↗
PubMed1995

Superantigens and their role in infectious disease.

Although the exact mechanisms by which superantigens may contribute to the pathogenesis of diseases are unknown, it seems increasingly likely that they have a role in the induction and pathogenesis of disease. The studies described here demonstrate that in several different diseases either bacterial or viral superantigens can be isolated from patients. There is also a preferential expansion of particular V beta T-cell subsets, which is a common feature of superantigen stimulation. From the work that has been done to date it can be hypothesized that superantigens may act in several ways. They may stimulate and activate T cells that are autoreactive and lead to the induction or exacerbation of autoimmune disease, as in RA. Alternatively, they may lead to the depletion of T-cell subsets based on V beta expression, thereby resulting in the severe reduction in lymphocytes in certain immunodeficiency diseases such as AIDS. But perhaps the most likely contribution of superantigens to disease pathogenesis is seen indirectly by their effect on the immune system-particularly the stimulation of large numbers of T lymphocytes expressing the same V beta domain. Thus it is likely that the direct effect of various T-cell-derived inflammatory mediators (i.e., interleukins and other cytokines) released by these activated T lymphocytes is the primary cause of disease pathology via response to superantigen stimulation. In addition to the diseases discussed here, there are a number of other diseases in which a potential role for superantigens is being studied. These include autoimmune diseases seen after group A streptococcal infections in which the streptococcal M protein has been postulated to act as a superantigen such as scarlet fever, rheumatic heart disease, and poststreptococcal glomerulonephritis. Other diseases being studied include psoriasis, lupus-like disease, and lymphoproliferative diseases (reviewed in Kotzin et al.). In the coming years the exact role of superantigens and the specific mechanisms by which they contribute to disease should be more clearly defined. Our understanding of these molecules could also lead to new therapies for the treatment of these diseases.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Synaptology of cultured olfactory bulb cells.

Cultured embryonic mouse olfactory bulb cells formed asymmetric, symmetric, axodendritic, and dendrodendritic synapses. These neurons contained electron lucent, dense core, and coated vesicles. Dense core and coated vesicles had an average diameter of 71 and 80 nm, respectively. Two statistically different populations of electron lucent vesicles were found, based on synaptic symmetry: electron lucent vesicles from asymmetric synapses had an average diameter of 46 nm with an estimated volume of 49,000 nm3, whereas those from symmetric synapses had an average diameter of 44 nm and an estimated volume of 42,000 nm3. Because these values are similar to those found for intact olfactory bulb, the synapses of these cultured cells have some of the same morphological characteristics as those in the intact olfactory bulb.

Animals↗
PubMed1994

Selective myelotoxicity of propanil.

Propanil, a commonly used herbicide, has been previously shown to be immunotoxic for selected immune functions as well as specific cell types, such as the macrophage. Propanil has also been shown to cause a methemoglobulinemia and anemia through direct action on the erythrocyte. Demonstrated toxicity to both macrophages and erythrocytes raised concern for the possible myelotoxicity of propanil which could contribute to the observed effects of exposure. Therefore, the effect of propanil on several stem and progenitor cell types was assessed 7 days after acute propanil exposure. The results described herein show that propanil, at doses of 50-200 mg/kg body wt, resulted in reduction in the number of myeloid stem cells and early myeloid and erythroid progenitor cells. No reduction in the numbers of more differentiated myeloid and erythroid progenitor cells was noted at even the highest dose used (200 mg/kg). In addition, no statistically significant difference in number of leukocytes per femur was noted. These data suggest that propanil is myelotoxic to early hemapoietic stem cells, but that this reduction is apparently compensated by proliferation of more differentiated progenitor cells for the myeloid and erythroid lineages. It remains unknown whether chronic exposure leads to progressive depletion of additional myeloid and erythroid cells.

Animals↗
PubMed1994

Morphological characteristics of cultured olfactory bulb cells.

Cultured olfactory bulb cells from embryonic mice had ultrastructural characteristics similar to those of many cell types in the intact adult mouse olfactory bulb. Identified cultured cells included mitral/tufted cells, granule cells, short-axon cells, and fibrous and protoplasmic astrocytes. Cultured neurons were found as individual cells, clusters or aggregates. Clusters consisted of a loose array of neurons that appeared to be densely interconnected by neurites. However, few neurites or fascicles emanated from clusters to adjoining areas. Aggregates consisted of many small, usually rounded, neurons piled on top of one larger neuron, or on more than one, with typically many neurites and fascicles projecting to adjacent aggregates, clusters or individual neurons. Neurites of cultured olfactory bulb cells were well developed, and some were several millimeters long. Synapses were very prominent in these cultures, especially in aggregates, clusters, and fascicles. Electron-lucent, dense-core, and coated vesicles were present. Polarity, shape, and length of the long axis (size) of 815 cultured neurons, identified by positive anti-microtubule-associated protein 2 staining, were documented. Cultured neurons varied in size from 9 to 27 microns, with an average size of 16 microns. Elliptical bipolar (35%), triangular multipolar (21%), and round unipolar (15%) were the most common polarity/shape combinations found in culture. Multipolar, triangular, triangular multipolar, and elliptical bipolar cells increased in size with increasing age of culture. The relative proportions of triangular, multipolar, elliptical multipolar, and triangular multipolar cells decreased, whereas the relative proportions of round, unipolar, and round unipolar cells increased with increasing age of culture. These changes in population subtypes and cell size may indicate continued differentiation and maturation of cultured neurons.

Animals↗
PubMed1994

Food labeling.

Explore the source record for details and available documents.

Food Labeling↗
PubMed1994

The conceptualisation of clinical facts.

There has never been a fact that has not already been conceptualised. To enter into discourse as a fact, whatever the case may be in the world that is of immediate concern must always already be symbolically mediated, that is, already a specialised version of that aspect of the world. To become a 'clinical' fact, however, 're'conceptualisation is required; before then the clinician has only details. Details become clinically significant when, implicitly or explicitly, they are situated and redefined in a context of interrelated clinical narratives. These narratives are based partly on dialogue and partly on the general theories or metanarratives provided by one or another school of psychoanalytic thought. During psychoanalysis, new clinical facts continue to be conceptualised, and these often alter their own formative contexts, for they include the consequences of previous conceptualisations. Consequently, facticity is always in flux as, over time, understanding alters meaning and emphasis. Even the apparently brute fact of corporeality changes with changes of age, culture, historical epoch, gender of patient, and phase of analysis. In analysis, a central role is played by insight into the functions served by the analysand's uses of 'fact' in the course of devising, unconsciously, transferenceAcountertransference enactments. Illustrated case material is provided.

Adult↗
PubMed1994

The contemporary Kleinians of London.

A review of the modern British modifications of Melanie Klein's approach. While featuring its advantages along with its systematic problems, this review also argues for its recognition by all analysts as a true branch of Freudian analysis. It points up egopsychological aspects of this approach, showing that it includes some elements that are distinctive and others that overlap standard Freudian practice. Mention is made of some incompleteness of theorizing and some seemingly avoidable tendency toward interpretive imbalance, both of which are seen to be signs of the times in contemporary analytic thinking.

Defense Mechanisms↗
PubMed1994

A classic revisited: Kurt Eissler's 'the effect of the structure of the ego on psychoanalytic technique'.

Eissler's influential contribution, which introduced the idea of the parameter of technique, extended Freud's later contributions so that they would apply to thoughtful analytic work with hard-to-treat patients. Aimed at sharpening the baseline of psychoanalytic technique-interpretation--and differentiating ego-psychological work from Franz Alexander's modifications in particular, Eissler's 'parameter' was progressively and perversely made into a coercive, if not punitive, concept. Looking back on it now, one can see that, in addition to its merits, the paper advocates an orientation that is no longer beyond dispute. In contrast to the present pluralistic state of psychoanalytic approaches to treatment, certain aspects of Eissler's paper seem unacceptably finalistic, restrictive and uncritically committed both to assumptions about continua in development and pathological states and to an operational approach to diagnosis.

Adolescent↗
PubMed1994

One perspective on the Freud-Klein controversies 1941-45.

Comments on the complex relations obtaining between, on the one hand, tradition, innovations and existential perspective and, on the other, presuppositions about method, evidence and truth are prefaced by a review of the helpful and hindering attitudes and conduct of the three parties to these controversial discussions, the third group being the indigenous ('independent') British group. This group directed the process into productive channels against great odds. The subsequent history of psychoanalysis shows, in addition to increased organisational stability and tolerance in times of crisis, an evolving enrichment and refinement of theory and practice in all three groups. Those following Melanie Klein have developed further their own kind of ego-psychological emphasis, while those following Anna Freud and 'the Viennese' around her have developed a more inclusive theoretical and clinical perspective, one that makes more salient the influence of the very first years of life and early infantile aggression as well as accepting a broadening of the idea of transference to include child analysis. This history supports the view that pluralism in psychoanalysis has been of much benefit.

Austria↗
PubMed1992

Induction of a cellular immune response to a foreign antigen by a recombinant Listeria monocytogenes vaccine.

A recombinant strain of Listeria monocytogenes that stably and constitutively expresses Escherichia coli beta-galactosidase was used as a live vaccine vector. BALB/c mice were immunized orally or parenterally with the recombinant L. monocytogenes, and their cellular and humoral immune responses to beta-galactosidase were measured. Spleen cells taken 1 week after oral inoculation or 5 weeks after oral or parenteral inoculation (with a boost at 4 weeks) showed beta-galactosidase-specific CTL responses. The CTL line derived from mice immunized i.p. was also shown to be class I restricted and Thy-1.2+, CD8+, and TCR alpha beta+. All mice immunized with the recombinant L. monocytogenes had positive delayed-type hypersensitivity responses to heat-killed L. monocytogenes, but only 15% had a positive delayed-type hypersensitivity reaction to beta-galactosidase. Individual serum samples from mice immunized i.p. or i.v. were tested for antibody to beta-galactosidase. Approximately 11% had low positive titers for beta-galactosidase antibodies. These results demonstrate that both oral and parenteral immunization with recombinant L. monocytogenes results in a cellular immune response to the foreign protein, which is primarily a specific CD8+ CTL response.

Animals↗
PubMed1992

Forcing expression of a soybean root glutamine synthetase gene in tobacco leaves induces a native gene encoding cytosolic enzyme.

Glutamine synthetase (GS; EC 6.3.1.2) is present in different subcellular compartments in plants. It is located in the cytoplasm in root and root nodules while generally present in the chloroplasts in leaves. The expression of GS gene(s) is enhanced in root nodules and in soybean roots treated with ammonia. We have isolated four genes encoding subunits of cytosolic GS from soybean (Glycine max L. cv. Prize). Promoter analysis of one of these genes (GS15) showed that it is expressed in a root-specific manner in transgenic tobacco and Lotus corniculatus, but is induced by ammonia only in the legume background. Making the GS15 gene expression constitutive by fusion with the CaMV-35S promoter led to the expression of GS in the leaves of transgenic tobacco plants. The soybean GS was functional and was located in the cytoplasm in tobacco leaves where this enzyme is not normally present. Forcing this change in the location of GS caused concomitant induction of the mRNA for a native cytosolic GS in the leaves of transgenic tobacco. Shifting the subcellular location of GS in transgenic plants apparently altered the nitrogen metabolism and forced the induction in leaves of a native GS gene encoding a cytosolic enzyme. The latter is normally expressed only in the root tissue of tobacco. This phenomenon may suggest a hitherto uncharacterized metabolic control on the expression of certain genes in plants.

Base Sequence↗
PubMed1992

Natural killer cells mediate protection induced by a Salmonella aroA mutant.

We have previously shown that an avirulent strain of Salmonella typhimurium, SL3235, blocked in aromatic synthesis, confers high levels of resistance to challenge with virulent Salmonella as early as 3 days postvaccination. In the present studies, it was found that immunization with SL3235 resulted in high levels of natural killer (NK) cell activity in the spleens and peritoneal cavities of C3H/HeJ mice, as measured by cytotoxicity against YAC-1 targets. NK cell activity was at its maximum 2 to 4 days after immunization and was ablated by in vivo or in vitro treatment with anti-asialo GM1. In vivo treatment with anti-asialo GM1 during the first week after immunization with SL3235 depleted NK cell activity and markedly increased mortality in mice challenged with a virulent Salmonella strain. These results are compatible with a role for NK cells as one important component in the resistance against virulent Salmonella infection induced by a live, attenuated vaccine.

Animals↗
PubMed1989

Abnormal typical pattern of platelet function and thromboxane generation in unstable angina.

Platelet aggregation (PA), platelet thromboxane B2 (TXB2) generation and 14C 5-hydroxytryptamine (5HT) release were studied in 13 patients with unstable angina, and compared to 14 patients with stable angina and 16 healthy controls. A typical pattern, distinct in 4 aspects from stable angina patients or controls, was observed in the unstable angina patients. ADP or collagen induced shape change was 3-4 times greater, the extent of epinephrine induced PA was nil or very low, the extent of collagen induced 14C 5HT release was also reduced while collagen induced platelet TXB2 generation was increased in spite of a reduced extent of PA. The extent of ADP or collagen induced PA was also significantly reduced. These results indicate a platelet membrane abnormality occurring presumably during contact of the circulating platelets with a non-occlusive thrombus observed at sites of ruptured plaques in unstable angina patients. Since also the pattern (20-30% overlap with control values) was distinct from that of stable angina patients, it might indicate an active thrombotic process. Plasma beta-thromboglobulin (beta TG) and TXB2 levels and serum TXB2 generation were also studied in the cardiac patients and controls and in another 10 patients with advanced peripheral occlusive arterial disease (POAD). Plasma beta TG and TXB2 levels were slightly elevated in the unstable angina patients and markedly elevated in the POAD patients. Serum TXB2 generation was, however, elevated in the stable angina patients (p less than 0.002) and more so in the unstable angina patients (p less than 0.001) compared to controls or to POAD patients. This was presumably mediated through enhanced thrombin generation. These results suggest that the measured plasma beta TG variable in the unstable angina patients is not useful in the assessment of in vivo platelet activation. It is presumably reflecting the sum of local enhanced platelet activation (at sites of ruptured plaques) and of reduced function of the "defective" circulating platelets. The ability of the platelets of unstable angina patients to generate large amounts of TXB2 if occurring in vivo might induce an intense coronary vasospasm.

Adult↗
PubMed1988

Induction of activated macrophages in C3H/HeJ mice by avirulent Salmonella.

A single injection of viable Salmonella typhimurium SL3235, an avirulent organism blocked in the aromatic pathway, induced the generation of activated peritoneal macrophages in three different C3H mouse strains, including macrophage-defective C3H/HeJ mice. Macrophages obtained from immunized mice were cytotoxic for B16 melanoma cells, P815 mastocytoma cells, and TU-5 fibrosarcoma cells and microbicidal in vitro for the obligate, intracellular, protozoan parasite Leishmania major. The capacity of live SL3235 to activate C3H/HeJ macrophages contrasts with the failure of live Bacillus Calmette-Guérin to induce activated macrophages in this mouse strain. Although viable SL3235 were capable of fully activating cells of both normal and defective mice, a dose-dependent difference was observed in the number of organisms necessary for induction of tumoricidal macrophages in C3HeB/FeJ (normal) and C3H/HeJ (defective) animals. As few as 80 viable SL3235 were capable of activating C3HeB/FeJ macrophages whereas 5 X 10(4) organisms were required to activate C3H/HeJ macrophages. Maximal macrophage activation occurred 7 to 10 days after SL3235 inoculation in C3H/HeJ and C3HeB/FeJ mice. Acetone-killed cells of SL3235 had some but not all of the activity of the living Salmonella. A single in vivo injection of the nonviable preparation resulted in the induction of tumoricidal macrophages in C3HeB/FeJ but not in C3H/HeJ mice, even when tested over a wide dosage range. Injection of acetone-killed cells of SL3235 did, however, result in a population of primed macrophages in C3H/HeJ mice, as explanted cells could be induced to express activated macrophage effector activities after additional treatment in vitro with either LPS or IFN-gamma. Thus, in vivo administration of viable SL3235 is, by itself, capable of eliciting the full series of steps required for activation of C3H/HeJ macrophages, whereas killed SL3235 only provides signals sufficient to prime these defective macrophages for further activation in vitro. AI 15613

Animals↗