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Biomedical subjects

P Ferrero

Publications and source records attributed to P Ferrero.

At least 19 recordsLinked to original sources

Peripheral benzodiazepine receptor messenger RNA is decreased in lymphocytes of generalized anxiety disorder patients.

BACKGROUND: The aim of this study was to assess whether the decrease of peripheral benzodiazepine receptor (pBR) number in peripheral blood mononuclear cells (PBMC), previously observed in patients with generalized anxiety disorder, is paralleled by changes in the relative content of messenger RNA (mRNA) encoding pBR. METHODS: Eight patients with a DSM-III-R diagnosis of generalized anxiety disorder were examined before, during, and after 2'-chloro-N-desmethyl-diazepam treatment. Eight healthy subjects were analyzed in parallel. The relative content of pBR mRNA was determined by reverse-transcriptase-polymerase chain reaction, using beta-actin as internal standard. Kinetic binding properties of pBR were measured using 3H-PK11195 as a ligand. RESULTS: pBR and pBR mRNA were significantly decreased in untreated generalized anxiety disorder patients as compared to controls (by 45% and 70%, respectively). Both pBR density and mRNA levels returned to control values during treatment or after withdrawal, which also coincided with recovery from anxiety. CONCLUSIONS: These results suggest that the turnover rate of pBR is reduced in PBMC of generalized anxiety disorder patients, and that this change occurs at the transcriptional level.

Adult

Peripheral-type benzodiazepine receptors on human blood mononuclear cells are not regulated by ovarian steroids.

Peripheral-type benzodiazepine receptors (pBZr) have been shown to be sensitive to hormonal perturbations, including changes in ovarian steroids. This study examines whether estradiol and progesterone modulate pBZr binding in membranes of human blood mononuclear cells, as measured by binding of both 3H-PK 11195 and 3H-Ro 5-4864. Our findings were negative. There was no steroidal modulation of pBZr binding to these membrane preparations in vivo in normal women studied at different sex-steroid phases of the menstrual cycle, or during 8-30 weeks of pregnancy. There was also no effect of hormones on the binding sites in cultures of mononuclear cells treated with estradiol or progesterone (up to 10(-5) M) over a period between 2 and 72 h. Further, we performed in vitro competition experiments, which showed that both steroids are not active at the pBZr. Our data suggest that pBZr located in human blood mononuclear cells are insensitive to the physiological variations of circulating female hormones.

Benzodiazepinones

Associated polyneuropathy and demyelinating disease. Case report.

We report a case in which an acute Guillain-Barré-like syndrome was quickly followed by a central demyelinating disease, documented by the clinical findings as well as by magnetic resonance imaging (MRI), electrophysiological and cerebrospinal fluid examinations. The close follow-on of the clinical signs seems to exclude a simple coincidence of two separate diseases and it may constitute further evidence for a possible etiological link between central and peripheral myelin damage. We discuss the possibility of a common pathogenic factor underlying central and peripheral demyelination.

Acoustic Stimulation

An analysis of peripheral type benzodiazepine receptors on blood mononuclear cells during high dose steroid treatment of multiple sclerosis.

We report here a study of peripheral type benzodiazepine receptors (pBZr) in mononuclear cells (MNC) from blood of patients with multiple sclerosis (MS) during periods of stable and active disease and from normal controls. Most active MS patients were retested in a longitudinal study, both during a treatment with high dose steroids and while medication free. Active MS produces a significant decrease of receptor density compared with the controls whereas remission of the disease shows no effect. Four weeks of steroid treatment restore binding density to normal levels, and two weeks of drug withdrawal result in a small, but significant increase in number of the binding sites compared with the control value. We suggest that the number of pBZr in blood MNC might change during the clinical course and steroid therapy of MS.

Adult

[Predictive factors of response to chemotherapy in epidermoid cancer of the esophagus. Study apropos of 60 patients and evaluation of a response score].

The aim of this study was to select predictive factors for response to chemotherapy in esophageal squamous cell carcinoma. Sixty patients, aged between 39 and 77 years (mean 61.5) received two initial chemotherapy sessions of 5 FU (1 mg/m2/24 h) and cisplatinum (20 mg/m2/24 h) during four days. Sixteen clinical, endoscopic, biological, and histological factors were collected. The response to chemotherapy was evaluated one month after completion of the second session by means of endoscopic and computed tomographic data. Thirty-two percent (CI: 20-44 percent) of patients had an objective response to chemotherapy (according to WHO criteria). Univariate analysis showed two predictive factors: obstructing pattern of tumor (P less than 0.01) and albuminemia less than 35 g/l (P less than 0.01). A response score was calculated with a stepwise regression model. The score correctly predicted a satisfactory response to chemotherapy with a sensitivity and specificity of 84.2 and 73 percent, respectively. Overall survival of these patients was statistically higher (P less than 0.001) compared with patients without any response. A satisfactory response to chemotherapy in patients with esophageal squamous cell carcinoma can be expected according to certain pretreatment factors.

Aged

A study of 3H-PK 11,195 binding to "peripheral-type" benzodiazepine receptors on human lymphocytes. Evidence of decreased binding in hepatic encephalopathy.

In an attempt to assess the involvement of the "peripheral-type" benzodiazepine receptors (pBDZR) in hepatic encephalopathy (HE), we examined the binding of the isoquinoline carboxamide derivative 3H-PK 11,195 to lymphocyte membranes from a group of patients with liver cirrhosis with or without clinical signs of HE and normal controls. Lymphocyte 3H-PK 11,195 binding is saturable, with high affinity and presents the pharmacological specificity corresponding to pBDZR. A significant 40% decrease in the number of 3H-PK 11,195 binding sites, without a concomitant change in the apparent affinity, is observed in the group with HE as compared to the controls, but not in that with liver diseases without HE. The decrease in binding capacity correlates significantly with the clinical grading of HE, but not with age, sex, aetiology of cirrhosis or presence of surgical shunt. In contrast to the reduction of pBDZR, 3H-N-methylscopolamine binding to lymphocyte muscarinic receptors is not affected in HE. These findings are consistent with a role for pBDZR in HE and may stimulate studies of endogenous modulators and pharmacological agents for these receptors in the disease.

Adult

An analysis of lymphocyte 3H-N-methyl-scopolamine binding in neurological patients. Evidence of altered binding in Alzheimer's disease.

Muscarinic cholinergic receptors were analysed in lymphocyte membranes from 35 patients with early (n = 20) and late onset (n = 15) Alzheimer's disease (AD), 86 patients with other neurological disorders and 60 normal controls by the specific binding of 3H-N-methyl-scopolamine (3H-NMS). The number of binding sites of 3H-NMS (Bmax) was significantly decreased both in early and late onset AD groups as compared with age-matched controls, by 54% and 40%, respectively, whereas the apparent binding affinity (Kd) was the same in all disease and control groups. In addition, the average Bmax in early AD was significantly lower than in late AD. The density of the binding of 3H-NMS was also significantly lower in a subgroup of old subjects with Down's syndrome (DS), whereas no changes were found in younger individuals with DS or in patients with Parkinson's disease, whether they were demented or not, multi-infarct dementia, myasthenia gravis or epilepsy. In the AD group, the difference in binding sites was unrelated either to the severity of dementia or disease duration. Treatment of the patients with cholinergic agents did not alter the binding values in any of the examined group. We conclude that the alteration of lymphocyte muscarinic receptors is highly associated with AD, but whether this reflects the central cholinergic deficit in these patients is uncertain.

Adolescent

Peripheral-type benzodiazepine receptors in anxiety disorders.

Peripheral benzodiazepine receptors (pBDZr) were analyzed in lymphocyte membranes from patients with anxiety disorders (generalized anxiety disorder (GAD), n = 15; panic disorder (PD), n = 10; obsessive-compulsive disorder (OCD), n = 18), other mental disorders (n = 40) and 50 healthy controls, by the specific binding of 3H-PK11195. The number of binding sites (Bmax) was significantly decreased in groups with both GAD and OCD as compared with age-matched controls, by 45% and 25% respectively, whereas the binding affinity (Kd) was the same in all disorder and control groups. Conversely, no changes in binding capacity was observed in the other disorder groups and particularly in the one with PD. The abnormality in pBDZr observed in patients with GAD was restored to a normal value after long-term treatment with 2'-chloro-N-desmethyldiazepam, which also coincided with their recovery from anxiety. Our data suggest that the clinical heterogeneity in anxiety disorders might be related to different biological mechanisms and that lymphocyte pBDZr might be useful in demonstrating these differences.

Anti-Anxiety Agents

Modulatory effect of some steroid hormones, their glucuronides and ouabain-like compounds on Cavia cobaya kidney Na+,K(+)-ATPase activity.

1. Ouabain-like compounds (approx. mol. wt 700, 2,000 and 4,000 Da) were purified from plasma of essential hypertensive patients. 2. Dose-response experiments performed with (a) steroid hormones, (b) their glucuronides and (c) ouabain-like compounds, emphasize a modulatory effect [activation of the Na,K-ATPase at very low concentrations of ligand, inhibition at higher levels; apparent Ki: (a) between 1 and 0.5 mM; (b) between 1 and 0.5 microM; and (c) between 10 and 1 nM; maximum enhancement of the enzymatic activity: (a) +20%; (b) +45%; and (c) +100%]. 3. Displacement experiments of [3H]ouabain evidence a high competition of the ligands towards the cardioglycoside. The relative I50s are: (a) between 1 and 0.5 mM; (b) between 10 and 1 microM; and (c) between 10 and 0.01 nM.

Animals

Aging effects on brainstem auditory evoked potentials.

Since age effects on central conduction time in the acoustic pathway are still debated, we recorded brainstem auditory evoked potentials in 154 normoacoustic subjects, with no history of neurologic or otologic pathology. Linear regression has been used for statistical analysis. Data obtained show an age-related prolongation of latency values which is particularly marked for wave I, while other waves (particularly wave III) do not show a significant change. Thus, interpeak latency (IPL) values do not increase with increasing age: in particular IPLs I-II and I-III decrease, showing a negative "r" value, and IPLs I-V and II-V (which is to be considered the true "central conduction time" through the acoustic pathway) do not show a significant change. Our data seem to demonstrate that the aging process is essentially a peripheral phenomenon which does not involve the central part of the acoustic pathway.

Acoustic Stimulation

[3H]N-methylscopolamine binding to muscarinic receptors in human peripheral blood lymphocytes: characterization, localization on T-lymphocyte subsets and age-dependent changes.

The properties of the binding of the muscarinic receptor ligands, [3H]quinuclidinyl benzilate ([3H]QNB) and [3H]N-methylscopolamine ([3H]NMS) in human mononuclear cells were compared. The binding of [3H]QNB showed a high, non-specific component and lack of saturability in both intact mononuclear cells and preparations of lysed mononuclear cell membranes. Conversely the specific binding of [3H]NMS had a high affinity and was saturable at concentrations greater than 30 nM in both intact and broken cells. Classical muscarinic receptor antagonists displaced specific binding of [3H]NMS binding according to the law of mass action, while displacement curves for pirenzepine and muscarinic agonists were very shallow (nH less than 1), suggesting the presence of more than one subtype of muscarinic receptor on mononuclear cell membranes. Binding studies with [3H]NMS to purified mononuclear cell subpopulations demonstrated that muscarinic binding sites were mainly localized on thymus-derived (T) lymphocytes and large granule lymphocytes. Moreover evidence is presented of an age-dependent increase of the density of muscarinic binding sites on T-lymphocytes. The results are discussed in terms of the usefulness of the binding of [3H]NMS in studying the physiological function of muscarinic receptors on human T-lymphocytes and their possible changes in patients with neurological diseases.

Adult

Diazepam binding inhibitor-like immunoreactivity (DBI-LI) in human CSF. Correlations with neurological disorders.

Cerebrospinal fluid (CSF) levels of the anxiogenic neuropeptide diazepam binding inhibitor (DBI) were determined by radioimmunoassay in 281 patients who underwent evaluation for neurological problems. Serial dilution curves and reverse-phase high pressure liquid chromatography showed that the immunoreactive material in CSF behaved just as authentic DBI extracted from human brain. Furthermore in the assay there was no evidence of interference from CSF samples deprived of DBI by immunoaffinity. In 82 patients with no evidence of major lesions in the central nervous system, who acted as controls, the CSF DBI content was shown to be age- and sex-related. No correlation was observed with the CSF protein concentration. In patients with different types of dementia, the levels of CSF DBI were significantly increased in a group with normal pressure hydrocephalus. No significant differences were found between Alzheimer's disease, multi-infarct dementia, or dementia with Parkinson's disease and controls. In non-demented patients with Parkinson's disease the levels of DBI were increased in a subgroup with depressive disturbances whereas no differences was observed in the non-depressed cases. The content of DBI was markedly reduced in 5 cases with olivopontocerebellar atrophy and in 4 with spinocerebellar ataxia. In all the other disorders studied the levels of DBI were similar to or slightly lower (multiple sclerosis) than those of the controls. The origin of DBI in cerebrospinal fluid is uncertain; a number of various possibilities are discussed concerning the proposed role of DBI as modulator of brain GABAergic transmission.

Adolescent

A diazepam binding inhibitor (DBI)-like neuropeptide is detected in human brain.

Diazepam binding inhibitor (DBI), a 11,000 MW neuropeptide, which coexists with GABA and elicits proconflict responses in the rat, has been purified and partially sequenced from rat brain. We now report purification and characterization of a DBI-like neuropeptide from human brain. Its molecular weight and pharmacological profile is identical to that of rat DBI but differs in the amino acid composition and immunologically. The tryptic fragments of human DBI differ from rat DBI in the HPLC elution profile and in the amino acid sequence. Using high affinity specific human DBI antibodies, the distribution of DBI-like immunoreactivity in bioptic samples of human brain appeared to be similar to that of DBI found in rat brain. DBI-like immunoreactivity was also found in spinal fluid of human volunteers. The cerebrospinal fluid content of this peptide might be used as a probe to study whether spinal fluid DBI content changes in neuropsychiatric disorders.

Amino Acid Sequence

Diazepam-binding inhibitor. A brain neuropeptide present in human spinal fluid: studies in depression, schizophrenia, and Alzheimer's disease.

Diazepam-binding inhibitor is a novel peptide purified to homogeneity from rat and human brain. Diazepam-binding inhibitor is present, though not exclusively, in gamma-aminobutyric acid (GABA)-containing neurons where it is believed to inhibit GABAergic neurotransmission mediated by GABA by binding to the benzodiazepine-GABA receptor complex. Since an impairment of central GABAergic tone has been postulated to be associated with a number of neuropsychiatric disorders, we measured human diazepam-binding inhibitor immunoreactivity in the cerebrospinal fluid (CSF) of patients suffering from endogenous depression, schizophrenia, and dementia of the Alzheimer's type. Patients with major depression had significantly higher concentrations of human diazepam-binding inhibitor immunoreactivity in CSF when compared with age- and sex-matched normal volunteers, while no difference in CSF diazepam-binding inhibitor immunoreactivity was found in schizophrenics or patients with dementia of the Alzheimer's type when compared with controls. The possibility is discussed that the increased CSF human diazepam-binding inhibitor immunoreactivity observed in depressed patients may represent a functional disinhibition of GABAergic neurotransmission associated with depression.

Adult

Main nitrogen balance determinants in malnourished patients.

Factors influencing nitrogen balance during total parenteral nutrition have been investigated in 38 malnourished patients studied for a cumulative period of 280 days. According to multiple regression analysis, nitrogen intake (0.213 +/- 0.004 g kg-1 day-1, mean +/- SD) proved to be the major determinant of a positive nitrogen balance (0.018 +/- 0.004 g kg-1 day-1), followed by non-protein energy intake (43.3 +/- 0.5 kcal kg-1 day-1). Total calorie intake to predicted basal energy expenditure and non protein calorie to nitrogen ratios appeared to have little significance on nitrogen balance, when corrected for the two former variables.

Female