Analysis of glutamate uptake and monosodium glutamate toxicity in neural retina monolayer cultures.
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Animals↗
Biomedical subjects
R Adler
Publications and source records attributed to R Adler.
Neurite-promoting factor in conditioned medium from RN22 Schwannoma cultures: bioassay, fractionation, and properties.
On polyornithine (PORN) substrata dissociated 8-day chick embryo ciliary ganglionic neurons will survive if the culture medium is supplemented with Ciliary neuronotrophic Factor. However, neuritic growth will not occur unless the substratum is derivatized with a PORN-bindable Neurite Promoting Factor (PNPF). In this preliminary study we report that soluble PNPF can be (1) assayed by a convenient in vitro system; (2) obtained in relatively large amounts from serum-free media conditioned over RN22 Schwannoma cultures; (3) concentrated by using Amicon XM100 ultrafiltration; and (4) separated from nearly all of the non-active protein by using ion-exchange chromatography. The partially purified PNPF can be concentrated using XM100 and is heat- and protease-sensitive. In the course of these fractionation studies we observed in some cases a concentration-dependent interference with the expression of PNPF activity in the bioassay; we propose graphical methods to permit the simultaneous determination of PNPF and the extent of such interference. Different treatments that affected the interference property did not always affect PNPF activity in a reciprocal manner, leaving open the possibility that the interference with PNPF activity results from reversible alteration of the PNPF molecule, or that there exists a separate interfering agent.
Animals↗
Formal speech stylistics and type A behavior in 38 subjects during nonstress interviews.
Open-ended interviews of 90 min length of 38 patients were analyzed with respect to speech stylistics, shown by Schucker and Jacobs to differentiate individuals with type A personality features from those with type B. In our patients, Type A/B had been assessed by the Bortner Personality Inventory. The stylistics studied were: repeated words swallowed words, interruptions, simultaneous speech, silence latency (between question and answer) (SL), speed of speech, uneven speed of speech (USS), explosive words (PW), uneven speech volume (USV), and speech volume. Correlations between both raters for all speech categories were high. Positive correlations between extent of type A and SL (r = 0.33; p = 0.022), USS (r = 0.51; p = 0.002), PW (r = 0.46; p = 0.003) and USV (r = 0.39; p = 0.012) were found. Our results indicate that the speech in nonstress open-ended interviews of type A individuals tends to show a higher emotional tension (positive correlations for USS PW and USV) and is more controlled in conversation (positive correlation for SL).
Coronary Disease↗
Pseudodementia or Ganser syndrome in a ten year old boy.
A case of pseudodementia, occurring in a 10 year old boy following a minor head injury and associated with a claim for compensation, is presented. The case is unusual in the age of the patient and the failure to respond to treatment including prolonged hospitalization. The case is discussed in the light of the available literature and an attempt is made to clarify the confusion surrounding the terms pseudodementia and Ganser Syndrome.
Age Factors↗
Study of 90 hepatitis B surface antigen carriers in Israel.
A study of 90 asymptomatic hepatitis B surface antigen (HBsAg) carriers in Jerusalem showed a predominance of males over females (4:1) and of North African Jews over Jews of European or American Origin. The predominance of males remained apparent, but was not significant, when origin was controlled. Possible sources of infection were contact with jaundiced patients (29%), dental treatment (58%) and drug addiction (8%). Fifty-one percent had hepatitis B core antibody (anti-HBc) of the IgM class, 2% had hepatitis B e-antigen (HBeAg), 94% hepatitis B e-antibody (anti-HBe) and 93% had hepatitis A antibody (anti-HAV). Fourty-two percent had donated blood at least once prior to the detection of the carrier state. Fifty-five percent of 128 asymptomatic family contacts had evidence of hepatitis B virus infection. Minor abnormalities in liver function tests were found in 22% of the carriers and splenomegaly in 11%. Of ten liver biopsies performed in these cases, one had chronic active hepatitis, five had minimal histological changes, and four were normal.
Adolescent↗
Cholinergic neuronotrophic factors: V. Segregation of survival- and neurite-promoting activities in heart-conditioned media.
Chick embryo ciliary ganglionic (CG) neurons will not survive in monolayer culture unless special supplements are provided in the medium. We have previously reported that two such supplements, chick embryo extract and medium conditioned over chick heart cell cultures (HCM) share the capacity to support survival of CG neurons but differ in their neurite-promoting effects. Thus, embryo extract elicited neuritic outgrowth only on collagen and HCM did so only on polyornithine (PORN), although both agents supported neuronal survival on both substrata. We report here the separation and quantitation of two different HCM components. One is a trophic agent which supports survival of CG neurons on either collagen or PORN, but does not seem to adsorb to either substratum. The other is a neurite-promoting factor (NPF) which adsorbs to PORN but not to collagen. Overnight incubation of HCM on PORN yields two products: (i) an NPF-deprived HCM, that has no neurite-promoting activity and (ii) an NPF-coated PORN, that promotes neuritic development of CG neurons trophically supported by either embryo extract or NPF-deprived HCM. CG requirements for neuritic outgrowth were also examined in explant cultures. No neurites were present after 24 h when explants were cultured in plain medium on PORN. Very extensive radial neuritic outgrowth was observed when explants were cultured in HCM on fresh PORN, or in NPF-deprived HCM on NPF-derivatized PORN. In contrast to what happens with dissociated cells, neuritic outgrowth was also present when ganglia were cultured in NPF-deprived HCM on fresh PORN. However, neurites grew radially only to a limited extent, after which they adopted a circular pattern grossly concentric to the ganglionic explant. It is proposed that explanted ciliary ganglia produce a neurite-promoting factor that coats the PORN substratum in widening circles.
Animals↗
[A characteristic, elicited from the medical history, which helps in the differentiation between organic and psychogenic symptoms].
It is often difficult to differentiate between the organic and psychogenic origin of symptoms. One helpful characteristic for deciding the organic origin of a symptom is its change in intensity and/or quality as a function of the motor behavior of the patient. It can be assessed while taking the history. This observation is illustrated with reference to three cases. Its theoretical background corresponds to FREUD'S statement about the real versus the intrapsychic origin of a perception: A perception (in our case: a symptom) is real (of organic origin) if it can be made to disappear (to change in intensity and/or quality) by means of a motoric action on the part of the subject (i.e. of the patient).
Adult↗
Survival, proliferation and morphological specialization of mouse Schwann cells in a serum-free, fully defined medium.
Neonatal mouse dorsal root ganglionic (DRG) cell dissociates were cultured in a synthetic medium with horse serum or the serum-free supplement N1 (insulin, transferrin, progesterone, putrescine, selenium). Serum-supplemented cultures with added nerve growth factor (NGF) yielded neurons, small flat and spindle cells (Schwann) and large flat cells (fibroblastic elements). However, in serum-free, N1-supplemented medium plus exogenous NGF, neurons and Schwann cells predominated, with very few large flat cells. In the N1 medium most Schwann cells assumed a typical spindle shape and were associated with neuritic processes when neurons were present. Upon addition of serum, virtually all of the Schwann cells appeared to abandon physical contact with the neurites and develop a more flattened morphology. In N1 medium without NGF (no neurites), most Schwann cells still assumed a spindle shape and formed characteristic chain-like associations. Autoradiographic techniques, as well as numerical analyses, demonstrated that in N1 medium Schwann cells were able to proliferate when associated with neurites but only slightly so in their absence. These Schwann cells showed a marked increase in proliferation when serum was added regardless of the presence or absence of neurites. The above observations may provide a basis for the preparation of purified Schwann cells, alone or in combination with their neurons.
Animals↗
Cholinergic neuronotrophic factors. III. Developmental increase of trophic activity for chick embryo ciliary ganglion neurons in their intraocular target tissues.
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Animals↗
Nerve growth factors and control of nerve growth.
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Animals↗
Chronic renal disease in childhood: doubts, hopes and expectations.
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Adolescent↗
Cholinergic neuronotrophic factors: fractionation properties of an extract from selected chick embryonic eye tissues.
An aqueous extract derived from selected intraocular tissues of 15-day chick embryos contains a soluble macromolecular agent which is capable of ensuring the survival of 8-day chick embryonic ciliary ganglionic neurons in monolayer culture. When this ciliary neuronotrophic factor (CNTF) was concentrated using ultrafiltration and subjected to Sephadex G100 and G200 chromatography, activity was detected in most of the eluted fractions. A peak of the most active fractions was eluted in a region corresponding to a molecular weight of 35-40 X 10(3) and contained about 20-30% of the applied protein. CNTF activity bound readily to DE-52 cellulose resin at neutral pH and was eluted with NaCl in a narrow region containing about 20-40% of the applied protein. Gel electrophoretic staining profiles of the active DE52 fraction indicated considerable (but still only partial) simplification in protein composition. While significant CNTF activity losses were incurred in response to each of the above treatments, an active material could be conveniently generated in one working day in milligram amounts having a specific activity of 60,000 trophic units/mg protein. This trophic activity is in the same range as that of the only other known neuronotrophic factor, Nerve Growth Factor.
Animals↗
Interaction of concanavalin A with herpes simplex virus infected cells.
Incubation of herpes simplex virus (HSV) infected cells with concanavalin A (Con A) interferes with binding of the Fc portion of antibody. In addition, the lectin inhibits complement mediated cytolysis, probably by interference with antibody binding. These results suggest that binding sites of both Fc and HSV antibody contain residues which attract Con A.
Animals↗
Sodium transport in red cells of patients with acute viral hepatitis.
The red blood cell composition was determined in 25 patients with acute viral hepatitis and in 26 normal subjects. The potassium concentration was 83.4 +/- 4.11 mmol/kg red cells (mean +/- SD) in hepatitis red blood cells and 79.7 +/- 4.74 mmol/kg red cells in the control samples (P < 0.005). There were no significant differences between the sodium content of normal and hepatitis red blood cells. 22Na-Efflux was determined in red blood cells of 17 patients with acute viral hepatitis and 18 normal subjects. The mean sodium efflux rate constant was 0.212 +/- 0.036 in red cells of patients with hepatitis and 0.295 +/- 0.046 in the control samples (P < 0.001). This difference resulted from a reduction in both the active and residual portions of the red blood cell sodium pump in the patients with viral hepatitis. Red blood cells of patients with acute viral hepatitis accumulated sodium at a significantly slower rate than normal red blood cells. The increase in osmotic fragility after 24 hr incubation at 37 degrees C in the absence of glucose was less prominent in hepatitis red blood cells than in normals. The findings of a reduced sodium efflux and slower accumulation of sodium during incubation, suggest that red blood cells from patients with viral hepatitis are less permeable to sodium, thereby leading to a new steady-state, characterized by a reduced sodium efflux.
Adolescent↗
Systematic study of four years of internship.
As part of the continuing effort to study perceived attitudes, stresses, and coping mechanisms of pediatric interns in a hospital-based training program, this paper focuses in depth on how attitudes toward patients and toward the internship experience become more negative in the course of the internship year. Sources of stress and changes in coping mechanisms are documented. There wer no significant effects of gender or marital status on interns' attitudes. Gender and marital status were not correlated with performance during the year, and attitudes were not consistently correlated with performance. Discussion of the significance of these findings in pediatric training and suggestions for redirection of pediatric training programs are made.
Attitude of Health Personnel↗
Cholinergic neuronotrophic factors: I. Survival, neurite outgrowth and choline acetyltransferase activity in monolayer cultures from chick embryo ciliary ganglia.
Two key components of neural development and regeneration, survival of the involved neurons and elongation of neuritic elements, are likely to depend on the availability of an appropriate trophic drive to these neurons. At present, only one trophic factor, Nerve Growth Factor, is known to ensure both survival and neuritic growth for its target neurons. A search for a second such agent, a putative cholinergic neuronotrophic factor (CNTF), has been undertaken using as indicators neuronal survival, neurite outgrowth and choline acetyltransferase (CAT) activity in monolayer cell cultures. Eight-day chick embryo ciliary ganglia yielded two monolayer culture systems which appear to be well suited for a CNTF assay. Ciliary ganglionic dissociates, seeded on a highly adhesive collagen substratum, show no neuronal survival by 24 h if the medium is supplemented only with serum or chick embryo extract. However serum and embryo extract combined support survival of, and extensive neuritic outgrowth from, nearly the theoretical number of ganglionic neurons seeded. Alternatively, ciliary ganglionic neurons can be made to survive and produce a profuse neuritic outgrowth on polyornithine-coated dishes if supplied with medium conditioned over chick embryo heart muscle cultures, as already described by other laboratories. The two trophic sources differ markedly in their effects on the ganglionic neurons when tested on collagen or polyornithine substrata, and in some cases when different serum supplements are used. Neuronal survival, neurite production and, possibly, CAT activity appear to be subject to independent regulation. The culture systems used in this study can be developed into quantitative bioassays for the isolation of the different agents responsible for neuronal survival and neurite promotion, and for the investigation of their activities.
Animals↗
Cholinergic neuronotrophic factors: intraocular distribution of trophic activity for ciliary neurons.
Chick ciliary ganglionic neurons require an interaction with their peripheral targets for survival during a critical period of their embryonic development in vivo. It has recently been shown that survival of these neurons in dissociated cell cultures is supported by extract from whole chick embryo. In this study, an assay system based on microwell cultures of ciliary ganglionic neurons was used to demonstrate that a very rich source of trophic factor for them is the intraocular target tissues they innervate. Out of 8000 trophic units present in a 12-day embryo, 2500 were contained in the eye. A subdissection of the eye showed its activity to be localized in a fraction containing the ciliary body and choroid coat, with a specific activity almost 20-fold higher than that of the whole embryo. This selective intraocular distribution at a time when survival or death of ciliary ganglionic neurons is decided in vivo suggests that this soluble factor may be involved in the normal development of the ciliary ganglion.
Animals↗
The environment of axonal migration in the developing chick retina: a scanning electron microscopic (SEM) study.
We have made a SEM study of the basal intercellular spaces of the retina in chick embryos of different developmental stages. Since this is the environment where optic axons grow, the structural characteristics of this region might play some role in the orientation of axonal migration towards the choroid fissure. The basal region of undifferentiated retinas is formed by the vitreal expansions of neuroepithelial cells. In pre-axonal stages, the intercellular spaces between these expansions do not show any preferential orientation towards the fissure. The growth cones of ganglion cell axons appear in an apicobasal direction and turn towards the fissure immediately beneath the vitreal surface. Fasciculation is an early event during development and, in the more advanced stages, the vitreal expansions from retinal cells are placed in rows following the same orientation as the axon bundles. These observations are discussed in relationship to current hypotheses on axonal migration and orientation.
Animals↗