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C A Ross

Publications and source records attributed to C A Ross.

At least 235 records · Page 13Linked to original sources

Rat brain endoplasmic reticulum calcium pools are anatomically and functionally segregated.

Autoradiographic imaging can localize 45Ca2+ selectively accumulated via the Ca2+, Mg2(+)-ATPase into endoplasmic reticulum stores in rat brain slices. 45Ca2+ accumulation is markedly stimulated by oxalate and displays a heterogeneous distribution which resembles the mRNA distribution for a sarcoendoplasmic reticulum Ca2+, Mg2(+)-ATPase. Inositol 1,4,5-triphosphate [I(1,4,5)P3] inhibits 45Ca2+ accumulation selectively into regions corresponding to those enriched in I(1,4,5)P3 receptor-binding sites and in Ca2+, -Mg2(+)-ATPase mRNA. Thus rat brain endoplasmic reticulum calcium stores are anatomically and functionally differentiated.

Animals↗

Dissociative experiences in the general population.

The Dissociative Experiences Scale was administered to a random sample of 1,055 adults in the city of Winnipeg. Results showed that scale scores did not differ between men and women and were not influenced by income, employment status, education, place of birth, religious affiliation, or number of persons in the respondent's household. Dissociative experiences are common in the general population and decline with age. The findings suggest that dissociative disorders may also be common in the general population.

Adult↗

Association between family history of affective disorder and the depressive syndrome of Alzheimer's disease.

For each of 41 index patients with probable Alzheimer's disease and a first episode of major depression and 71 nondepressed Alzheimer's disease patients, two first-degree relatives were interviewed by a rater blind to presence or absence of depression in the proband. The depressed patients had significantly more first- and second-degree relatives with depression than did control subjects. The lifetime risk for major depression, adjusted for differences in age distribution, was significantly greater in first-degree relatives of index patients, suggesting that depression in Alzheimer's disease is genetically related to primary affective disorder. Alzheimer's disease may be useful for studying aspects of depressive pathophysiology.

Age Factors↗

Structured interview data on 102 cases of multiple personality disorder from four centers.

Patients with multiple personality disorder (N = 102) at four different centers were interviewed with the Dissociative Disorders Interview Schedule. The presenting characteristics of the patients at all four centers were very similar. The clinical profile that emerged included a history of childhood physical and/or sexual abuse in 97 (95.1%) of the cases. The subjects reported an average of 15.2 somatic symptoms, 6.4 Schneiderian symptoms, 10.2 secondary features of the disorder, 5.2 borderline personality disorder criteria, and 5.6 extrasensory experiences; their average score on the Dissociative Experiences Scale was 41.4. The results indicate that multiple personality disorder has a stable, consistent set of features.

Borderline Personality Disorder↗

Twelve cognitive errors about multiple personality disorder.

Multiple personality disorder (MPD) is often responded to with extreme skepticism by mental health professionals. This skepticism is based in part on twelve cognitive errors about the disorder that can be corrected by argument and research evidence. The errors include the mistaken ideas that MPD patients have more than one personality; that the diagnosis means such patients are not responsible for their actions; that MPD patients are really just borderlines; that MPD is an iatrogenic artifact; that MPD can be created experimentally; that MPD must be rare; that MPD is a therapeutic metaphor; that everyone has different personalities; that MPD will go away if you ignore it; that patients pretend to have MPD in order to please the therapist; that the abuse histories of MPD patients are confabulated; and that one must be a hypnotist to treat MPD. It is important to correct these cognitive errors because MPD is not rare. It can be diagnosed with good reliability and its features are stable and consistent in a number of large published series. Although definitive treatment-outcome studies have not been conducted, clinical experience to date suggests that the disorder can often be cured with psychotherapy. After successful integration, MPD patients function much better than before, and can be released from the mental health system.

Borderline Personality Disorder↗

Adult children of problem drinkers in an urban community.

In a medium-sized Canadian city, 581 randomly selected households were contacted and responded to a survey on the impact of parental alcohol problems. Twenty-two per cent of the respondents indicated that at least one of their parents had a drinking problem. The biological father was affected in 81%. Compared with the rest of the sample, the adult children of problem drinkers were younger but they did not differ in income or education. Adult children of problem drinkers were more likely to have parents who were divorced or separated; to be divorced, separated, or remarried themselves; to be heavy drinkers and have indications of alcohol problems; and to use more sources of help for problems with stress and anxiety and problems with alcohol. They did not differ from those without parental drinking problems on measures of current positive and negative affect.

Adult↗

Trypanosoma congolense: appearance and distribution of variable antigen types during metacyclic differentiation in vitro.

Differentiation of epimastigotes and production of infective metacyclic forms of Trypanosoma congolense were examined in a culture system which enabled manipulation of the population density of insect forms. Scanning electron microscopy of cultures revealed the attachment sites of epimastigotes in detail, showing them to be attached as 'clusters' or 'bundles' and having associated fibrillar structures. Dividing epimastigotes were observed either within individual bundles or in association with two bundles. Metacyclic forms were detected by an immunofluorescence antibody test (IFAT) using metacyclic variable-antigen type (M-VAT) specific monoclonal antibodies, by day 7 after seeding cultures. Trypanosomes expressing M-VATs appeared singly in bundles, observed by both IFAT and an immunogold labelling method. Statistical analysis using Poisson calculations suggested that, in general, the distribution of metacyclics expressing individual M-VATs was random throughout cultures.

Animals↗

Carboxypeptidase E (enkephalin convertase): mRNA distribution in rat brain by in situ hybridization.

Carboxypeptidase E (CPE), also referred to as enkephalin convertase or carboxypeptidase H (EC 3.4.17.10), is present in neurotransmitter secretory granules and can remove C-terminal basic residues following endopeptidase cleavage during peptide processing. Using in situ hybridization with 35S-labeled oligonucleotide probes, we have mapped the localization of CPE mRNA in the rat brain. Specificity for CPE was confirmed by control experiments, which included production of identical patterns hybridization with 3 different antisense oligonucleotide probes, loss of label with RNase pretreatment of sections or co-incubation with excess unlabeled probe, and lack of labeling with sense orientation probes. In addition, the regional distribution of CPE mRNA by Northern blot analysis corresponded with distribution of labeling by in situ hybridization. The highest levels of CPE mRNA were found to be present in the pyramidal cells of the hippocampus, the pituitary anterior and intermediate lobes, the ependymal cells of the lateral ventricle, the endopiriform nucleus, the basolateral amygdala, the supraoptic nucleus, and the paraventricular nucleus. Intermediate levels were present in the thalamus, medial geniculate nucleus, lateral septal nucleus, piriform and entorhinal cortex, nucleus of the tractus solitarius, cerebellar cortex, pontine nuclei, and inferior olive. The lowest levels were found in the hippocampal granule cell layer, lateral hypothalamus, globus pallidus, and brain stem reticular formation. Ibotenic acid lesions of the hippocampus eliminated the majority of the label, which had been present over pyramidal cells, though labeling was increased over areas of reactive gliosis, suggesting that activated astrocytes can also synthesize CPE mRNA. In general, the localization of CPE mRNA in the rat brain corresponded to the distribution of enkephalin and other peptide neurotransmitter-synthesizing neurons, though CPE mRNA was also present in neurons that do not secrete known peptides and in reactive glia. The widespread yet specific localization of CPE mRNA in the rat brain suggests it may be an excellent marker for peptide synthesizing cells in the CNS.

Adrenal Glands↗

Inositol 1,4,5-trisphosphate receptor localized to endoplasmic reticulum in cerebellar Purkinje neurons.

Inositol 1,4,5-trisphosphate (InsP3) mediates the effects of several neurotransmitters, hormones and growth factors by mobilizing Ca2+ from a vesicular, non-mitochondrial intracellular store. Many studies have indirectly suggested the endoplasmic reticulum (ER) to be the site of InsP3 action, though some have implicated the plasma membrane or a newly described smooth surfaced structure, termed the calciosome. Using antibodies directed against a purified InsP3-receptor glycoprotein, of relative molecular mass 260,000, in electron microscope immunocytochemical studies of rat cerebellar Purkinje cells, we have now localized the InsP3 receptor to ER, including portions of the rough endoplasmic reticulum, a population of smooth-membrane-bound organelles (smooth ER), a portion of subplasmalemmal cisternae and the nuclear membrane, but not to mitochondria or the cell membrane. These results suggest that in cerebellar Purkinje cells, InsP3-induced intracellular calcium release is not the property of a single organelle, but is effected by specialized portions of both rough and smooth ER, and possibly by other smooth surfaced structures. The present findings are the first immunocytochemical demonstration of an InsP3 receptor within a cell.

Animals↗

Differentiating multiple personality disorder and complex partial seizures.

A number of reports have suggested that some cases of multiple personality disorder might be due to temporal lobe epileptic discharges. We have administered a structured interview, the Dissociative Disorders Interview Schedule, to 20 subjects with multiple personality disorder, 20 with complex partial seizures, and 28 neurologic controls. Subjects also completed the Dissociative Experiences Scale. Results show that multiple personality can be differentiated from complex partial seizures on a large number of items. The seizure patients did not differ from controls. The data indicate that the phenomenologies of these two disorders are distinct, and, therefore, there is little reason to assume a common etiology.

Adult↗

Somatic symptoms in multiple personality disorder.

A structured interview, the Dissociative Disorders Interview Schedule, was administered to 20 patients with multiple personality disorder, 20 with panic disorder, 20 with eating disorders, and 20 with schizophrenia. The frequencies of somatization disorder and of individual somatic symptoms in the four groups were compared. The multiple-personality patients reported more somatic symptoms than the other groups. Of the 20 multiple-personality patients, seven met the criteria for somatization disorder. The average number of somatic symptoms per multiple-personality patient was 13.5.

Adult↗

Endothelin: visualization of mRNAs by in situ hybridization provides evidence for local action.

Endothelin (ET) is a recently identified vasoactive peptide with three isoforms for which three genes have been cloned. The cellular sites of synthesis of this peptide have not yet been identified in vivo. Using Northern blot analysis, we have detected two forms of ET mRNA in rat tissues: a 3.7-kilobase form in the kidney, eye, and brain, a 2.5-kilobase form in the intestine, and both forms in the lung. We have localized these forms of ET mRNA in several rat tissues using in situ hybridization. In the 19-day rat fetus, ET mRNA is highest in the lung, intestine, and meninges. At high resolution, ET mRNA is localized in the lung to respiratory epithelial cells of bronchioles and apparently in blood vessels. In adult tissues, ET mRNA is present throughout the lung, in the renal medulla vasa recta, and in the iris of the eye. ET mRNA is synthesized in close proximity to ET binding sites in many organs (e.g., lung, kidney, intestine, and eye), suggesting a local action of this peptide. However, in other areas (e.g., heart and renal cortex), ET binding sites are present in the absence of ET mRNA, suggesting an action of ET from the bloodstream or from neurons. Northern blot analysis of ET mRNA in microvascular endothelial cells in culture indicates that ET is synthesized in small blood vessels and regulated similarly to its regulation in large vessels. Our results provide evidence that ET, like other regulatory peptides, may serve in several tissues as a neuromodulator or local hormone.

Animals↗

Brain phospholipase C isozymes: differential mRNA localizations by in situ hybridization.

mRNAs for isozymes of phospholipase C (PLC) were localized in rat brain by in situ hybridization with oligonucleotide probes for PLC isozymes I, II, and III of Rhee's group [Suh, P.-G., Ryu, S. H., Moon, K. H., Suh, H. W. & Rhee, S. G. (1988) Proc. Natl. Acad. Sci. USA 85, 5419-5423 and (1988) Cell 54, 161-169], and isozyme I of Bennett and Crooke [Bennett, C. F., Balcarek, J. M., Varrichio, A. & Crooke, S. T. (1988) Nature (London) 334, 268-270], which we designate PLC-A. The isozymes displayed different localizations. PLC-A mRNA was highest in the mitral cell layer of the olfactory bulb, choroid plexus, hippocampus and dentate gyrus, magnocellular hypothalamic nuclei, rostral raphe nuclei, and cerebellar Purkinje cells. PLC-I was highest in the internal granular cell layer of the olfactory bulb, cerebral cortex, caudate, nucleus of the lateral olfactory tract, reticular nucleus of thalamus, hippocampus and dentate gyrus, and granule cell layer of the cerebellum. PLC-II had a more widespread distribution, with relatively high levels in the internal granular layer of the olfactory bulb, hippocampus and dentate gyrus, and cerebellar Purkinje and granule cells. PLC-III label was low throughout the brain. These distributions suggest selective coupling of individual PLC isozymes with particular postsynaptic receptors. PLC-A may be preferentially associated with 5-hydroxytryptamine 1C receptors, vasopressin V1 receptors, and a subtype of glutamate receptors. PLC-I may be linked to muscarinic m1 and m3 receptors as well as other receptors. The distribution of PLC-II mRNA resembles that of src protooncogene, with which it displays sequence homology.

Animals↗

Effects of hypnosis on the features of multiple personality disorder.

The authors compared 57 patients with multiple personality disorder (MPD) who had been hypnotized both before and after diagnosis to 38 patients who had not been hypnotized during assessment or treatment. The two groups did not differ on the diagnostic criteria for MPD or in number of personalities. Hypnosis therefore does not have a gross distorting effect on the features of the disorder. Hypnosis may, however, affect the recall of sexual and physical abuse and the manifestation of certain types of alter personality. These include child personalities, personalities of different age, sex, or race, and protectors. The authors hypothesize that the hypnotized group may require hypnosis for access of more traumatic memories held by child personalities.

Adult↗