Protein synthesis in a synaptosomal fraction from squid brain.
Publication Date: 01/08/1993, on Molecular and cellular neurosciences
by Crispino M, Castigli E, Perrone Capano C, Martin R, Menichini E, Kaplan BB, Giuditta A
A synaptosomal fraction from squid brain containing a large proportion of well-presarved nerve terminals displays a high rate of [(35)S]methionine incorporation into protein. The reaction is dependent on time and protein concentration, is strongly inhibited by hypo-osmotic shock and cycloheximide, and is not affected by RNase. Chloramphenicol, an inhibitor of mitochondrial protein synthesis, partially inhibits the reaction. The ionic composition of the incubation medium markedly modulates the rate of [(35)S]methionine incorporation. Na(+) and K(+) ions are required for maximal activity, while complete inhibition is achieved by addition of the calcium ionophore A23187 and, to a substantial extent, by tetraethylammonium, ouabain, and high concentrations K(+). A thermostable inhibitor of synaptosomal protein synthesis is also present in the soluble fraction of squid brain. Using sucrose density gradient sedimentation procedures, cytoplasmic polysomes associated with nascent radiolabeled peptide chains have been identified in the synaptosomal preparation. Newly synthesized synaptosomal proteins are largely associated with a readily sedimented particulate fraction and may be resolved by gel electrophoresis into more than 30 discrete bands ranging in size from about 14 to 200 kDa. The electrophoretic pattern of the newly synthesized synaptosomal proteins is significantly different from the corresponding patterns displayed by the giant axon's axoplasm and by glial and nerve cell bodies (in the stellate nerve and ganglion, respectively). On the whole, these observations suggest that the nerve endings from squid brain are capable of protein synthesis.
The effects of gonadectomy and testosterone treatment on the Harderian gland of the green frog, Rana esculenta.
Publication Date: 01/08/1993, on Cell and tissue research
by Chieffi-Baccari G, D'Matteo L, d'Istria M, Minucci S, Serino I, Varriale B
The effects of gonadectomy and testosterone treatment on the fine structure of the Harderian gland in male and female green frogs were investigated in different periods of the year. Gonadectomy, carried out when the glands are in the lowest secretory phase (September), causes degenerative changes consisting of a reduction of the rough endoplasmic reticulum, the appearance of autolysosomes, and an increase of nuclear heterochromatin. These effects can be prevented by testosterone treatment. No castration effects are found during the recovery (November) and enhancement (April-May) phases of secretory activity. The results suggest that the frog Harderian gland's sensitivity to testosterone changes during the annual cycle. The androgen dependence of the Harderian gland is correlated with the presence of androgen receptors in both male and female frogs.
Familial amyloidotic polyneuropathy: description of an Italian kindred.
Publication Date: 01/05/1993, on Italian journal of neurological sciences
by Di Iorio G, Sanges G, Cerracchio A, Sampaolo S, Sannino V, Bonavita V
Familial amyloidotic polyneuropathy (FAP) is a heterogeneous group of genetic disorders characterized by progressive systemic deposition of extracellular amyloid fibrils, mainly affecting the peripheral nervous system (PNS). These disorders, inherited as an autosomal dominant trait, have frequently been described in various ethnic groups, but have rarely been reported in Italy. A 42 year-old man came to our observation for loss of pain and temperature sense in his legs. Clinical and laboratory data pointed to an amyloidotic polyneuropathy. This led us to discover a large italian kindred in which 19 members were affected by FAP. The diagnosis, established in 8 members on the clinical and laboratory findings, was ana-catamnestic in other 11. In this kindred the onset of the disease ranges from 35 to 50 years of age and the course is progressive and often fatal. The early symptoms are mainly related to autonomic disturbances and to peripheral neuropathy. Cardiac and renal involvement occurs frequently and may be life-threatening.
Solution structure of casokefamide.
Publication Date: 31/03/1993, on Biochemical and biophysical research communications
by Brantl V, Picone D, Amodeo P, Temussi PA
Casokefamide (Tyr-D-Ala-Phe-D-Ala-Tyr-NH2) is a synthetic peptide derived from the beta-casomorphin sequence, designed to increase the resistance to gastric proteases. Casokefamide binds to both mu and delta-opioid receptors, while beta-casomorphins and its fragments are typical mu-opioid receptor agonists. Furthermore, casokefamide can affect gastric acid and pancreatic exocrine secretions and also gastrointestinal motility. We have undertaken a conformational study on this peptide based on NMR measurements in a DMSOd6/H2O cryomixture at 265 K and energy calculations. The predominant conformation is characterised by the absence of regular structures and intramolecular hydrogen bonds. The conformation of the message domain is reminiscent of the shape of several peptidic and non peptidic opiates, with the D-Ala2CH3 group sandwiched between Tyr1 and Phe3 aromatic rings.
Slowly progressive aphasia associated with surface dyslexia.
Publication Date: 01/03/1993, on Cortex; a journal devoted to the study of the nervous system and behavior
by Chiacchio L, Grossi D, Stanzione M, Trojano L
We report an Italian patient affected by slowly progressive aphasia (SPA) lasting since four years when he first came to our observation. During the successive four years, we documented a progressive language decline resembling transcortical sensory aphasia, associated with a reading disorder corresponding to surface dyslexia, a form extremely rare in patients with native transparent language. His performance at standard intelligence tasks remained in the normal range, without any variation. CT scan showed left temporal atrophy. We emphasize the heterogeneity of the syndrome of SPA and suggest that it can represent one of the pictures of focal cortical degenerative disease, with variable onset, progression, and evolution.
Solution conformation of CCK9, a cholecystokinin analog.
Publication Date: 15/02/1993, on Biochemical and biophysical research communications
by Moroder L, D'Ursi A, Picone D, Amodeo P, Temussi PA
Cholecystokinin (CCK) is a peptide hormone endowed with several important biological activities, both in the central and peripheral nervous system. Previous conformational studies have dealt mainly with its C-terminal octapeptide fragment (CCK8), which represents the shortest fully circulating form of this hormone. We have undertaken a detailed NMR conformational study in a DMSOd6/H2O cryomixture at 278 K of the CCK analog H-Arg-Asp-Tyr(SO3H)-Thr-Gly-Trp-Nle-Asp-PheNH2 (CCK9) which retains all the bioactivities of CCK8, but was found to be remarkably more stable in acidic media and unaffected by air oxidation due to Met replacements. The predominant conformation contains a gamma-turn centered on Thr4, separated by Gly5 from a helical segment that comprises the C-terminal residues.
Memory for visuospatial patterns in Alzheimer's disease.
Publication Date: 01/02/1993, on Psychological medicine
by Grossi D, Becker JT, Smith C, Trojano L
Immediate memory for visuospatial information was assessed in patients affected by Alzheimer-type dementia but with unimpaired visuo-perceptual functions. Patients were given two tasks: one was a traditional visuospatial memory task (Corsi's block tapping test), the second explored specifically immediate memory for visuospatial patterns. The experiment was conducted in two parallel groups of patients in Italy and the United States, each with its own appropriate sample of normal control subjects. Results showed a specific deficit of visual working memory in demented patients, even in a task in which control subjects achieved error-free performance. These data are interpreted in the light of the Working Memory Model, and suggest that in dementia the functions of the Visuospatial Scratchpad, unlike the functions of the verbal subsystems, may be impaired.
Copying procedures in focal brain-damaged patients.
Publication Date: 01/01/1993, on Italian journal of neurological sciences
by Trojano L, De Cicco G, Grossi D
We aimed to ascertain whether non-apraxic, focal brain-damaged patients used abnormal constructional procedures. We tested a series of consecutive patients, classified according to lesion locus and side against a matched sample of normal volunteers. Subjects had to copy the Rey-Osterreith Figure, a complex and structured item that explores copying strategies. We used special testing and scoring methods to analyze different steps of the copy. Unlike the controls, the patients did not choose the central elements of the figure as guiding structures. All patient groups followed an equivalent "pathological", "piecemeal" procedure.
Long-term habituation to spatial novelty modifies posttrial synchronized sleep in rats.
Publication Date: 01/01/1993, on Brain research bulletin
by Montagnese P, Mandile P, Vescia S, Sadile AG, Giuditta A
To assess the role of posttrial synchronized sleep in the processing of a nonassociative task, adult male Sprague-Dawley rats with chronically implanted cortical electrodes for EEG recording were exposed to a Làt-maze, and horizontal (HA; corner crossing) and vertical (VA; rearings) activities were monitored during two 10-min test trials made at a 3-h (experiment 1) or 24-h (experiment 2) interval. EEG conventional recording was taken during 3 h under baseline conditions (day 1), and following exposure to the maze (day 2), and analyzed as to the amount (a), number (n), and mean duration (d) of synchronized sleep (SS) episodes followed by wakefulness (SS-->W) or by paradoxical sleep (SS-->PS). In both experiments there was a significant intertrial decrement (long-term habituation: LTH) for horizontal activity (LTH-HA), vertical activity (LTH-VA), and emotionality (LTH-E). In experiment 1, in comparison to baseline values, the posttrial SS-->PS(a) increased, mainly for the appearance of SS-->PS episodes in the 1st h. SS-->W(a) also increased in the first h. Correlative analyses among behavioral and sleep parameters showed that SS-->PS(n) and (d) covaried positively with LTH-HA relative to the entire test, and with LTH-VA relative to the second part of the test in the third h. Negative correlations were present between SS-->PS(n) and (d), and LTH-E. In experiment 2, exposed rats showed a lower SS-->PS(n) in the first hour and an increased SS-->PS(d) in the second hour. No change was observed as to SS-->W episodes.(ABSTRACT TRUNCATED AT 250 WORDS)
Impaired drawing from memory in a visual agnosic patient.
Publication Date: 01/11/1992, on Brain and cognition
by Trojano L, Grossi D
A case is reported of an associative visual agnosic patient who could not draw from memory objects he could recognize, even though he could copy drawings flawlessly. His ability to generate mental visual images was found to be spared, as was his ability to operate upon mental images. These data suggest that the patient could generate mental images but could not draw from memory because he did not have access to stored knowledge about pictorial attributes of objects. A similar functional impairment can be found in some other visual agnosic patients and in patients affected by optic aphasia. The present case allows a discussion of relationships among drawing from memory, imagery, and copying procedures.
Progressive rubella panencephalitis. Follow-up EEG study of a case.
Publication Date: 01/08/1992, on Acta neurologica
by Guizzaro A, Volpe E, Lus G, Bravaccio F, Cotrufo R, Paolozzi C
Progressive rubella panencephalitis is a very rare slow virus disease of the nervous system. The authors present a case, concerning a young man, aged 20 years, died 11 months after the onset of the disease. The following peculiarities of the case are emphasized: 1) the clinical symptomatology and the evolution (myoclonus, lack of cerebellar impairment) could suggest the diagnosis of SSPE; 2) the EEG recordings showed epileptiform abnormalities, long latency diffuse periodic complexes and--during interferon therapy and simultaneously with a temporary clinical improvement--the appearance of short latency anterior periodic complexes.
Effect of castration and testosterone therapy on harderian gland protein patterns of the golden hamster (Mesocricetus auratus).
Publication Date: 01/07/1992, on Comparative biochemistry and physiology. B, Comparative biochemistry
by Varriale B, Serino I, Minucci S, Chieffi G
1. Sodium dodecyl sulphate 7-12% gradient polyacrylamide gel electrophoresis of male and female hamster Harderian gland whole homogenate shows a clear-cut sexual dimorphism, which consists of the presence of two male-specific glycoproteins (168 and 116 kDa) and two specific female proteins (210 and 190 kDa). 2. In the male, castration causes a significant decrease in the concentration of the two glycoprotein fractions. 3. Replacement therapy with testosterone propionate (T) restores the intact male pattern.
beta-Actin and beta-Tubulin are components of a heterogeneous mRNA population present in the squid giant axon.
Publication Date: 01/04/1992, on Molecular and cellular neurosciences
by Kaplan BB, Gioio AE, Capano CP, Crispino M, Giuditta A
Previously, we have reported that the squid giant axon contains a heterogeneous population of polyadenylated mRNAs, as well as biologically active polyribosomes. To define the composition of this unique mRNA population, cDNA libraries were constructed to RNA obtained from the axoplasm of the squid giant axon and the parental cell bodies located in the giant fiber lobe. Here, we report that the giant axon contains mRNAs encoding beta-actin and beta-tubulin. The axonal location of these mRNA species was confirmed by in situ hybridization histochemistry, and their presence in the axoplasmic polyribosome fraction was demonstrated by polymerase chain reaction methodology. Taken together, these findings establish the identity of two relatively abundant members of the axonal mRNA population and suggest that key elements of the cytoskeleton are synthesized de novo in the squid giant axon.
Testosterone induction of poly(A)(+)-RNA synthesis and [35S]methionine incorporation into proteins of Rana esculenta Harderian gland.
Publication Date: 01/04/1992, on Molecular and cellular endocrinology
by Varriale B, Chieffi-Baccari G, d'Istria M, Di Matteo L, Minucci S, Serino I, Chieffi G
The role of androgens in the cyclic secretory activity of the Rana esculenta Harderian gland (HG) was studied. Total RNA showed a dramatic increase in October and May when the nuclear androgen receptors peak. During the resumption of the secretory activity a gradual increase of poly(A)(+)-RNA was detected; during the enhancement phase (May) a peak of the poly(A)(+)-RNA fraction was found. In in vitro experiments testosterone increased the incorporation of [3H]uridine into the poly(A)(+)-RNA fraction and also that of [35S]methionine into a newly synthesized protein fraction (100 kDa). The latter effect is prevented by the exposure of the cells to the antiandrogen, cyproterone acetate (CPA). These findings reveal that, besides hamsters, the HG is a target for androgens in the frog.
Conformational analysis of an opioid peptide in solvent media that mimic cytoplasm viscosity.
Publication Date: 01/04/1992, on Biopolymers
by Temussi PA, Picone D, Saviano G, Amodeo P, Motta A, Tancredi T, Salvadori S, Tomatis R
Many neuropeptides exert their action between the presynaptic vesicles and postsynaptic transmembrane receptors, crossing different layers of specialized cytoplasm. Biomimetic media usually employed to study bioactive peptides do not reproduce the physico chemical environment of cytoplasm--in particular, the high viscosity of this biological fluid. Here we describe a conformational study of a delta-selective opioid peptide, deltorphin I, at variable temperatures in several biocompatible media characterized by varying values of viscosity and dielectric constant. It was found that only viscosity, among these parameters, induces ordered conformations; that is, it acts as a conformational sieve. This finding suggests that the high viscosity of the intersynaptic fluid contributes, in addition to the membrane catalysis proposed by Schwyzer, in overcoming the so-called entropic barrier to the transition state of peptide-receptor interaction by selecting ordered conformations prior to receptor interaction. The folded conformer found in the 80:20 (v:v) DMSOd6/H2O cryoprotective mixture at 265 K has a shape consistent with those of rigid nonpeptidic opiates.