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R Kellner

Publications and source records attributed to R Kellner.

At least 19 recordsLinked to original sources
PubMed1992

A tryptophan-substituted member of the AKH/RPCH family isolated from a stick insect corpus cardiacum.

A neuropeptide, Cam-HrTH-I, has been isolated from the corpus cardiacum of the Indian stick insect Carausius morosus. The peptide causes hyperlipaemia in Locusta migratoria and hypertrehalosaemia in Periplaneta americana and is related to the previously isolated Cam-HrTH-II (pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2) by substitution, apparently by a hexose, on the Trp residue. This appears to be the first example of such substitution on a Trp residue.

Amino Acid Sequence↗
PubMed1992

Purification, characterization and structure of protein phosphatase 1 from the cilia of Paramecium tetraurelia.

A type 1 serine/threonine protein phosphatase (PP1) which is mostly localized in the excitable ciliary membranes from the protozoan Paramecium, was purified to homogeneity. Approximately 4 micrograms enzyme of 37 kDa was isolated from 100 l axenic culture. The enzymic properties were characterized using phosphorylase a from rabbit skeletal muscle as a substrate and several known effectors of mammalian PP1. The protozoan PP1 was enzymically indistinguishable from its mammalian congener. The amino acid sequence of the Paramecium PP1 was deduced from its cDNA. The full-length clone was obtained in several steps starting with a pair of degenerate primers made according to the two most conserved peptides of rabbit PP1 and PP2A. The gene encodes a protein of 36,392 Da. The identity of the cloned gene and the isolated ciliary PP1 was unequivocally established by microsequencing of four tryptic and cyanogen-bromide peptides which were generated from the purified protein. Paramecium PP1 shows 75% amino-acid-sequence identity with rabbit PP1 alpha. Areas of major differences are the C-termini and N-termini and a sequence between residues 219-242.

Amino Acid Sequence↗
PubMed1992

Interactions of rab5 with cytosolic proteins.

Rab proteins, one of the subfamilies of ras-like small GTP-binding proteins, are attached to cellular compartments or transport vesicles and may determine the specificity of fusion between these compartments and vesicles. It has been proposed that they alternate between a membrane-bound and a cytosolic state during their functional cycle. We have used a photo-crosslinking approach to identify their cytosolic interaction partners. In vitro synthesized rab5 was cross-linked in the presence of ATP mainly to three cytosolic proteins of 52, 65, and 85 kDa. Sucrose density gradient centrifugation of the cross-linked products suggested that they were part of a 10-14 S complex. Furthermore, rab5 was cross-linked to these and additional cytosolic proteins of 42, 48, and 160 kDa in the absence of ATP. Unexpectedly, upon ATP depletion of the cytosol cross-linked and noncross-linked rab5 was found in a sedimentable high molecular weight structure. Other members of the rab subfamily, but not N-ras, also sedimented under these conditions. Electrophoretic and electron microscopic analysis of the pelleted material revealed that it contained actin filament bundles and intermediate filaments. Our data suggest that cytosolic rab proteins interact with several proteins in a 10-14 S complex, and that the rab proteins may interact directly or indirectly via this complex with the cytoskeleton.

Actins↗
PubMed1992

Primary structures of the hypertrehalosemic peptides from corpora cardiaca of the primitive cockroach Polyphaga aegyptiaca.

Two hypertrehalosemic neuropeptides from the corpus cardiacum of the cockroach Polyphaga aegyptiaca were isolated by reversed-phase high-performance liquid chromatography, and their primary structures were determined by pulsed-liquid phase sequencing employing Edman chemistry, after enzymically deblocking the N-terminal pyroglutamate residue. As neither peptide was cleaved by carboxypeptidase, the C-terminus of each peptide was also blocked. Both peptides were found to be uncharged octapeptides with the sequences: Peptide 1: pGlu-Leu-Asn-Phe-Ser-Pro-Asn-Trp-NH2; and peptide 2: pGlu-Ile-Thr-Phe-Thr-Pro-Asn-Trp-NH2. Both peptides are clearly defined as members of the adipokinetic hormone/red pigment-concentrating hormone family of peptides. Whereas peptide 1 is identical in structure to the previously sequenced hypertrehalosemic neuropeptide from tenebrionid beetles (and is therefore designated the acronym Tem-HrTH), peptide 2 is a novel peptide and is designated the acronym Poa-HrTH. Both synthetic peptides caused an increase in the hemolymph carbohydrate concentration in P. aegyptiaca, specifically changing the trehalose concentration. The novel peptide Poa-HrTH was not very potent in elevating blood carbohydrates in the American cockroach.

Amino Acid Sequence↗
PubMed1992

Colorimetric determination of free and total cholesterol by flow injection analysis with a fiber optic detector.

A flow injection method for the determination of total and free cholesterol is presented. Cholesterol esterase and cholesterol oxidase are immobilized on aminoalkyl glass beads. The beads are packed into a tubular glass reactor. The cholesterol esters traversing through the esterase reactor are cleaved to cholesterol and fatty acids. The oxidase reactor converts cholesterol to cholest-4-en-3-one and hydrogen peroxide is generated. The sample stream is merged with reagent streams consisting of a peroxidase solution and a solution of 2,2'-azino-bis-(3-ethyl-benzthiazoline-6-sulfonic acid) diammonium salt, and a hydrogen peroxide-dependent color reaction takes place in a short coiled reactor. The signal is monitored by means of fiber optic instrumentation. Cholesterol concentration can be related to the absorption of the oxidized dye form at a wavelength of 425 nm. The working range is 0.5-0.8 mmol l-1, and the sample throughputs are 60 and 30 h-1 for free and total cholesterol, respectively.

Cholesterol↗
PubMed1992

Dyspnea, anxiety, and depression in chronic respiratory impairment.

In order to examine the relationship of dyspnea to anxiety and depression, the authors rated dyspnea using several methods in 50 patients with chronic respiratory impairment. Anxiety and depression were measured by the Symptom Checklist-90 and the Symptom Questionnaire. Results varied with the method of assessing dyspnea. Physician-rated dyspnea was significantly associated with patients' self-ratings of breathlessness as well as with pulmonary function tests, but not with any of the self-rating scales of emotions. Self-rated breathlessness was significantly associated with self-rated depression. In multiple regression analyses, depression was predictive of breathlessness. When the sample was limited to patients with chronic obstructive pulmonary disease, the results remained the same. The patients were significantly more depressed and anxious than matched family practice patients. In the study of the complex relationship of dyspnea to physical and emotional factors, it is desirable to use more than one measure of dyspnea because the results depend in part on the method of assessment.

Adult↗
PubMed1992

Panic disorder and hypochondriacal fears and beliefs.

The purpose of this study was to examine correlates of hypochondriacal fears and beliefs in patients with panic disorder (PD) (n = 54). They were evaluated using the structured diagnostic interviews for axis I and axis II disorders (SCID-UP-R and SCID-II). They were administered the Illness Attitudes Scales (IAS) as a measure of hypochondriacal fears and beliefs, the Hopkins Symptom Checklist 90 (HSCL), and the Fear Questionnaire (FQ). One half of the patients rated themselves as having substantial hypochondriacal fears and beliefs. The sample was divided into groups of patients seeking predominantly treatment or relief from symptoms (treatment-oriented), and those who were searching for a cause of their illness (explanation-seeking): the latter had significantly more hypochondriacal concerns. Avoidant, histrionic, and borderline personalities were more common in the hypochondriacal group. The results of several analyses suggest that patients with PD who are also agoraphobic, fear physical disease more and have more false beliefs of having a disease than PD patients without agoraphobia.

Adolescent↗
PubMed1992

Patterns of comorbidity in panic disorder and agoraphobia.

Diagnoses of comorbid disorders were determined in a sample of 54 patients with panic disorder as defined in DSM-III-R. The sample was divided into the following three groups: (1) uncomplicated panic disorder (PDU); (2) panic disorder with mild agoraphobia (PDM); and (3) panic disorder with moderate to severe agoraphobia (PDA). In comparison with patients with PDU, patients with PDA had higher comorbidity rates in general, received multiple comorbid diagnoses more frequently, had a higher prevalence of major depression, dysthymia, social phobia, generalized anxiety disorder, and obsessive-compulsive disorder, and scored higher on most measures of self-rated psychopathology. These findings support the notion that PDA may be a disorder essentially different from PDU.

Adult↗
PubMed1992

Diagnosis and treatments of hypochondriacal syndromes.

There are controversies in the literature about the diagnosis and most appropriate treatment of hypochondriasis. The author offers guidelines for diagnosis of hypochondriacal syndromes that have not been adequately dealt with in the literature and discusses the choice of treatments.

Anxiety Disorders↗
PubMed1992

VIP21, a 21-kD membrane protein is an integral component of trans-Golgi-network-derived transport vesicles.

In simple epithelial cells, apical and basolateral proteins are sorted into separate vesicular carriers before delivery to the appropriate plasma membrane domains. To dissect the putative sorting machinery, we have solubilized Golgi-derived transport vesicles with the detergent CHAPS and shown that an apical marker, influenza haemagglutinin (HA), formed a large complex together with several integral membrane proteins. Remarkably, a similar set of CHAPS-insoluble proteins was found after solubilization of a total cellular membrane fraction. This allowed the cloning of a cDNA encoding one protein of this complex, VIP21 (Vesicular Integral-membrane Protein of 21 kD). The transiently expressed protein appeared on the Golgi-apparatus, the plasma membrane and vesicular structures. We propose that VIP21 is a component of the molecular machinery of vesicular transport.

Amino Acid Sequence↗
PubMed1992

Self-rated inhibited anger, somatization and depression.

In order to examine the relationship of self-rated inhibited anger to somatization, the authors administered several self-rating scales, including the SCL-90 and a Likert scale pertaining to inhibited anger, to psychiatric patients and family practice patients of both sexes. In a linear stepwise regression, depression predicted inhibited anger in all four groups. Previous studies have reported an association of inhibited anger and somatization; the present study suggests that depression is the link between the two in the majority of patients. The relationship of inhibited anger to depression may have implications for psychotherapy.

Adolescent↗
PubMed1992

Changes in chronic nightmares after one session of desensitization or rehearsal instructions.

OBJECTIVE: The purpose of this study was to examine the effects of one session of instructions on the frequency of chronic nightmares and on self-rated distress. METHOD: Twenty-eight volunteers with chronic nightmares (mean duration = 19 years) were treated with either one session of desensitization with instructions on how to practice this treatment or with one session of instructions to change the nightmare and how to rehearse the new version. The authors administered four scales of the SCL-90 and the corresponding scales of the Symptom Questionnaire. RESULTS: At 7-month follow-up of 23 patients, there was a significant reduction in the frequency of nightmares and significant decreases in self-rated depression, anxiety, and hostility. There were no significant differences between the effects of the two types of treatment. In four patients, whose mean duration of nightmares was 23 years, the nightmares ceased. CONCLUSIONS: The results of this preliminary study suggests that the instructions given to the patients reduced the frequency of their chronic nightmares and decreased their self-rated distress.

Adult↗
PubMed1992

Hypochondriacal fears and beliefs, anxiety, and somatisation.

Four self-rating scales of hypochondriasis and the Symptom Checklist-90 were administered to 100 general practice (GP) patients and matched non-psychotic psychiatric out-patients. In a stepwise linear regression, self-rated somatic symptoms and anxiety predicted hypochondriacal fears and beliefs; self-rated depression did not appear as a predictor. There were differences between males and females and between psychiatric patients and GP patients in the associations of these constructs. These results varied in part with the scale of hypochondriasis used. Various scales of hypochondriasis appear to measure different features of the hypochondriasis syndrome. Fear of disease (disease phobia) was associated with anxiety, whereas a false belief of having a disease (disease conviction) was associated more with somatic symptoms.

Adolescent↗
PubMed1992

Primary structures of neuropeptides isolated from the corpora cardiaca of various cetonid beetle species determined by pulsed-liquid phase sequencing and tandem fast atom bombardment mass spectrometry.

A peptide with the same retention time on gradient reversed-phase high-performance liquid chromatography was present in the corpora cardiaca of 5 scarabaeid beetles, subfamily Cetoniinae: the three fruit beetle species Pachnoda marginata, P. sinuata and P. aemulae and the two protea beetle species Trichostetha fascularis and T. albopicta. Crude corpora cardiaca material from P. sinuata had a small hypertrehalosaemic effect in American cockroaches and a very weak hyperlipaemic activity in migratory locusts. Injections into P. sinuata caused hypertrehalosaemia when a dose of 1.0 corpora cardiaca equivalents was injected. An identical neuropeptide was isolated, by RP-HPLC, and sequenced by pulsed-liquid phase sequencing employing Edman chemistry after enzymically deblocking the N-terminal 5-oxopyrrolidine-2-carboxylic acid residue, as well as by collision-induced decomposition tandem fast atom bombardment mass spectrometry. The peptide is a blocked octapeptide: Glu-Leu-Asn-Tyr-Ser-Pro-Asp-TrpNH2, previously designated Mem-CC. The synthetic peptide is able to elicit haemolymph carbohydrates in P. sinuata upon injection of low doses. Activity studies using synthetic analogues of this peptide revealed that Tyr4 may be important for receptor recognition/binding. The peptide is synthesized in intrinsic cells of the corpus cardiacum as shown by in vitro incorporation of [3H]Trp and [14C]Tyr in Mem-CC.

Amino Acid Sequence↗
PubMed1992

Hypochondriacal concerns and attitudes toward illness in males and females.

OBJECTIVE: To review the published studies on the sex distribution of hypochondriasis, and to examine sex differences in hypochondriacal concerns and in attitudes toward illness. METHOD: The Illness Attitude Scales, Factors 2 and 3 of the Whiteley Index and the Symptom Checklist-90 (SCL-90) were administered to fifty randomly-selected female family practice patients ages eighteen to sixty-five, and to male patients matched by age in decades. From a pool of 130 consecutive nonpsychotic psychiatric outpatients, fifty females and fifty males were matched with the family practice patients. RESULTS: Although females rated themselves as more depressed than males in both groups, there were no significant differences between the sexes in hypochondriacal fears and beliefs. Psychiatric male patients reported the most adverse effects of bodily symptoms on work and leisure. There were no other significant differences between the sexes in any of the other attitudes toward illness or symptoms. Hypochondriacal concerns were more common in the psychiatric patients than in the family practice patients of both sexes. CONCLUSION: The review of published studies on the sex distribution of hypochondriasis suggests that disease phobia is more common in females, except for the cardiophobic syndrome, which is more common in males. The other reported differences are inconsistent and appear to be caused by referral biases, varying diagnostic criteria, and cultural factors. In our study, we found no substantial differences between males and females in hypochondriacal concerns and attitudes toward illness.

Adult↗
PubMed1992

The beneficial effects of one treatment session and recording of nightmares on chronic nightmare sufferers.

Twenty subjects with chronic nightmares for 17.2 years mean duration were randomly divided into two groups: Rehearsal and Recording. At inception, subjects in both groups were instructed to write down their nightmares for one month. The Recording group received no other intervention. Rehearsal subjects received a single treatment group session teaching an imagery rehearsal technique to reduce nightmare frequency. At inception and three months follow-up, both groups were compared for nightmare frequency and for self-rated distress with scales (Symptom Checklist and Symptom Questionnaire) measuring anxiety, depression, hostility, somatization and total distress. Nightmare frequency decreased significantly in both groups: Rehearsal group-7.2 per month to 2.0 per month (72% reduction) (p < 0.006); Recording group-9.4 per month to 5.0 per month (47% reduction) (p < 0.02). There were no statistically significant differences in the nightmare frequency reductions between groups. All anxiety, depression, somatization, hostility and total distress scores decreased substantially in the Rehearsal group. Most changes were significant. Changes in the Recording group were inconsistent and not significant. Two brief case histories are presented.

Adult↗
PubMed1991

Prodromal symptoms in affective disorders.

OBJECTIVE: The aim of this paper was to review the clinical and conceptual implications of the studies investigating prodromal symptoms of mania, depression, and panic disorder. METHOD: Twenty-four studies specifically addressing the issue of prodromal symptoms in mood and anxiety disorders were selected by computer search (Medline) and manual search of Index Medicus and the psychiatric literature. RESULTS: Most of the studies have described a prodromal phase in the development of mania, depression, and panic attacks. CONCLUSIONS: The appearance of prodromal symptoms may precede the full syndrome by weeks or months; if these symptoms are detected, recurrences of affective disorders (bipolar illness, unipolar depression, panic disorder) could be treated earlier and perhaps more effectively. DSM-III has emphasized the traditional clinical syndromes and cross-sectional descriptions. Appraisal of prodromal and residual phases may complement this approach. The longitudinal study of prodromes, the fully developed disorder, and residual states calls for an assessment of personality, neurotic traits, and their interaction in the evolution of affective disorders.

Anxiety Disorders↗