Search PubMed⌕ Search

Biomedical subjects

G Colombo

Publications and source records attributed to G Colombo.

At least 37 records · Page 2Linked to original sources
PubMed2001

Driven gait orthosis for improvement of locomotor training in paraplegic patients.

DESIGN: Single cases. OBJECTIVE: To compare the effects of manually assisted locomotor training in paraplegic patients with the automated training by a driven gait orthosis. SETTING: ParaCare, University Hospital Balgrist in Zurich, Switzerland. METHODS: Treadmill training with manual assistance and by a driven gait orthosis was applied to two spinal cord injured patients. The first patient had an incomplete lesion at C3, the second a complete lesion at C5. They were selected by convenience sample. The EMG activity of the leg muscles rectus femoris, biceps femoris, gastrocnemius medials (GM) and tibialis anterior (TA) was visually compared for the two training methods. GM and TA activity was also quantified by calculating the variation ratio between the EMG of the patients and a set of healthy subjects. RESULTS: No significant difference between the two training methods was found according to the leg muscle EMG activity. CONCLUSION: Neuronal centers in the spinal cord become activated in a similar way by the manually assisted and the automated locomotor training. With the driven gait orthosis training sessions can be prolonged and workload of therapists can be reduced, and therefore, the automated training represents an alternative to the conventional therapy.

Automation↗
PubMed2001

Alcohol reinforcement and voluntary ethanol consumption.

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The organizer/chair was Ting-Kai Li and the co-chair was Rainer Spanagel. The presentations were (1) Genetic differences in alcohol drinking and reinforcement: The sP and sNP Rats, by Giancarlo Colombo; (2) Ventral tegmental area-Neuroanatomical substrate for alcohol reinforcement, by William J. McBride; (3) Metabolic mapping of alcohol reinforcement, by Linda J. Porrino; (4) Role of opioid receptors in the ethanol-induced place preference in rats exposed to conditioned fear stress, by Tsutomu Suzuki; and (5) Repeated deprivations enhance the reinforcing properties of ethanol in alcohol preferring (P) rats, by Zachary A. Rodd-Henricks.

Alcohol Drinking↗
PubMed2001

Long term effects of locomotor training in spinal humans.

The long term effects of locomotor training in patients with spinal cord injury (SCI) were studied. In patients with complete or incomplete SCI coordinated stepping movements were induced and trained by bodyweight support and standing on a moving treadmill. The leg extensor muscle EMG activity in both groups of patients increased significantly over the training period, associated with improved locomotor ability in those with incomplete SCI. During a period of more than 3 years after training, the level of leg extensor EMG remained about constant in incomplete SCI in those who regularly maintained locomotor activity. By contrast the EMG significantly fell in those with complete SCI. The results suggest a training induced plasticity of neuronal centres in the isolated spinal cord which may be of relevance for future interventional therapies.

Adolescent↗
PubMed2000

Detection of t(4;14)(p16.3;q32) chromosomal translocation in multiple myeloma by reverse transcription-polymerase chain reaction analysis of IGH-MMSET fusion transcripts.

We and others have recently identified a novel recurring t(4;14)(p16.3; q32) translocation in multiple myeloma (MM) that leads to an apparent deregulation of the FGFR3 and WHSC1/MMSET genes. Because the presence of IGH-MMSET hybrid transcripts has been found in MM cell lines with t(4;14), they may represent a specific tumor-associated marker in MM. In this study, we developed a reverse transcription-PCR (RTPCR) assay for detecting chimeric transcripts from all of the 4p16.3 breakpoints identified thus far, and we used it to investigate a representative panel of 53 MM patients and 16 patients with monoclonal gammopathy of uncertain significance; in addition, t(4;14) was investigated in all of the MM patients by means of two-color fluorescence in situ hybridization. IGH-MMSET transcripts were found in 11 of the 53 (20%) MM cases and 1 of 16 (6%) cases of monoclonal gammopathy of uncertain significance. There was complete concordance between the RT-PCR and fluorescence in situ hybridization analyses of the MM cases. The results of this study indicate that RT-PCR is a sensitive and reliable method of detecting t(4;14) and suggest that it may be useful for monitoring the disease in a significant proportion of patients.

Adult↗
PubMed2000

Effects of changing stance conditions on anticipatory postural adjustment and reaction time to voluntary arm movement in humans.

1. The effect on reaction time (RT) and anticipatory postural adjustment (APA) of unexpectedly changing stance conditions was studied using a push or pull arm movement task. The aim was to evaluate the modifiability of RT and APA by an external perturbation associated with an automatic compensatory reaction. 2. Subjects standing on a moveable platform were asked to push or pull a rigid handle as quickly and as strongly as possible in response to the 'go-signal', a visual signal from a green or red light-emitting diode. Forward and backward translations of the platform were randomly induced at four time intervals after the go-signal. In some experiments to detect unspecific arousal there were no platform translations but an acoustic signal was given before the go-signal. Surface electromyographic activity (EMG) of upper arm and lower leg muscles was analysed. 3. During the push task both RT and the duration of APA (onset of APA till the force signal indicating hand action) were shorter during backward than during forward translation. During the pull task the effect of platform translations was the reverse. The delay between go-signal and onset of APA remained constant. Consequently, RT and APA became shorter when the platform was translated in the same direction as that in which the upper body was displaced by the push or pull movement, and longer when it was translated in the opposite direction. The effects were maximal when translations were induced 250 ms after the go-signal, but a difference was detected up to 375 ms. 4. Furthermore, with forward and backward platform translations RT was shorter when the translations were induced early rather than late after the go-signal. This was associated with a shortening of the delay between the go-signal and onset of APA, while APA duration remained constant. The shortened RT was in the range of that obtained when an acoustic signal was given just before the go-signal. 5. It is concluded that (i) both the RT and the duration of APA can be modified by a translation of the support surface in a functionally appropriate way by updating the internal representation of the actual stance condition within the central nervous system. Both RT and APA are shortened when the body displacement induced by the push or pull movement and platform translation have the same direction; conversely, an inappropriate translation of the feet requires a greater APA and leads to a longer RT; (ii) both APA and RT are modifiable by platform translation for more than half the time between the go-signal and the focal push or pull movement; (iii) an unspecific effect of platform translation on RT can be identified; it may be mediated by a different neuronal substrate.

Adult↗
PubMed2000

Systemic lupus erythematosus candidate genes in the Italian population: evidence for a significant association with interleukin-10.

OBJECTIVE: To determine whether 7 candidate genes, including tumor necrosis factor receptor II, bcl-2, CTLA-4, interleukin-10 (IL-10), CD19, Fcy receptor type IIA (CD32), and IL-1 receptor antagonist, may contribute to susceptibility to systemic lupus erythematosus (SLE) in the Italian population. METHODS: The association with SLE of intragenic markers for each candidate gene, including either microsatellites or dimorphisms, was analyzed. Gene frequencies of these gene markers were compared for patients and ethnically matched controls. Significance was tested by chi-square test on 2 x 2 tables and by Monte Carlo simulation on 2 x N tables. RESULTS: A significant increase was found in SLE patients (0.170 versus 0.095; chi2y = 4.11, P = 0.0425) in the frequency of the 140-basepair allele of the IL10.G microsatellite located in the promoter region of the IL-10 gene. This finding was confirmed in a second independent panel where, again, the frequency of the 140-bp allele was found to be significantly increased in SLE patients versus controls (0.176 versus 0.086; chi2y = 3.95, P = 0.0470). Considering the 2 panels together, the relative risk conferred by the presence of the 140-bp allele was 1.78 (95% confidence interval 1.19-2.66). Conversely, no significant association was detected for the remaining 6 candidate genes, even when the patients were stratified according to the presence of different clinical and immunologic features according to the presence of the associated HLA-DR or IL-10 alleles. CONCLUSION: Of the 7 candidate genes tested, only IL-10 was significantly associated with SLE in Italian patients. This genetic marker represents, apart from HLA, the only genetic susceptibility factor for SLE found so far in the Italian population.

Abatacept↗
PubMed2000

Potential use of medicinal plants in the treatment of alcoholism.

The present paper briefly reviews the most relevant experimental data on the reducing effect of some medicinal herbs on voluntary alcohol intake in animal models of alcoholism. Pueraria lobata, Tabernanthe iboga, Panax ginseng, Salvia miltiorrhiza and Hypericum perforatum proved to be effective in decreasing alcohol consumption. Reduction of alcohol absorption from the gastrointestinal system appears to be a common feature among most of the above plants. These data suggest that medicinal plants may constitute novel and effective pharmacotherapies for alcoholism.

Alcoholism↗
PubMed2000

Development of short-lasting alcohol deprivation effect in sardinian alcohol-preferring rats.

Alcohol deprivation effect (ADE), defined as a temporary increase in voluntary alcohol intake following a period of alcohol abstinence, was evaluated in selectively bred Sardinian alcohol-preferring (sP) rats. Alcohol was initially offered in free choice with water for 35 consecutive days (predeprivation phase). Subsequently, one group of rats was deprived of alcohol for 1, 3, 7, 15, 30, 90 or 180 consecutive days, while the second group had continuous access to alcohol (deprivation phase). Once alcohol was re-presented, alcohol intake in alcohol-deprived rats was recorded 1 and 24 h after alcohol re-presentation and compared to that monitored in alcohol-nondeprived rats over the same time periods (postdeprivation phase). Alcohol deprivation for 3 to 30 days resulted in a significant increase in voluntary alcohol intake only in the first hour of re-access. These results demonstrate the development of ADE in sP rats. However, the rapid return of alcohol intake to control levels is discussed as evidence in favor of a set-point mechanism capable of regulating alcohol-drinking behavior in sP rats.

Alcohol Drinking↗
PubMed2000

Characterization of the discriminative stimulus effects of gamma-hydroxybutyric acid as a means for unraveling the neurochemical basis of gamma-hydroxybutyric acid actions and its similarities to those of ethanol.

The present paper reviews the drug discrimination studies, both from the literature and from this laboratory, conducted to investigate the pharmacological profile of the discriminative stimulus effects of gamma-hydroxybutyric acid. Collectively, the results of these studies suggest that: (1) the discriminative stimulus effects of gamma-hydroxybutyric acid are composed of different cues, each one being the effect of gamma-hydroxybutyric acid on a specific receptor system; (2) the proportion of each component cue varies as the training dose of gamma-hydroxybutyric acid is increased; (3) the gamma-aminobutyric acid B-mediated cue is a major ingredient of the mixed stimulus of gamma-hydroxybutyric acid, but it is more prominent at high training doses than at low training doses of gamma-hydroxybutyric acid; and (4) positive modulation of the gamma-aminobutyric acid A receptor is a relevant part of the discriminative stimulus effects of low gamma-hydroxybutyric acid doses. Finally, data indicating symmetrical generalization between the discriminative stimulus effects of a specific range of doses of gamma-hydroxybutyric acid and those of ethanol are discussed in regard to their further support of the hypothesis that gamma-hydroxybutyric acid may exert its antialcohol effects through a substitution mechanism.

Animals↗
PubMed2000

Mechanism of the antialcohol effect of gamma-hydroxybutyric acid.

Treatment with gamma-hydroxybutyric acid has been reported to effectively decrease alcohol craving and consumption as well as alcohol withdrawal symptoms in alcoholics. We describe the results of animal studies demonstrating the ability of gamma-hydroxybutyric acid to reduce (1) the severity of ethanol withdrawal signs in rats rendered physically dependent on ethanol and (2) voluntary ethanol intake in selectively bred Sardinian alcohol-preferring rats. Furthermore, we review experimental data suggesting that gamma-hydroxybutyric acid and ethanol have several pharmacological effects in common. Relevant similarities are: (1) stimulation of firing rate of dopaminergic neurons and dopamine release in specific rat brain areas; (2) development of cross-tolerance to the motor-impairing effects after repeated administration in rats; 3) abuse potential, as indicated by self-administration of pharmacologically relevant doses of gamma-hydroxybutyric acid in rats and mice; (4) induction of anxiolytic effects in rats; and (5) induction of similar discriminative stimulus effects, as evidenced by symmetrical generalization in a drug discrimination study in rats. These lines of evidence are discussed in relation to gamma-hydroxybutyric acid exerting its antialcohol effects by a substitution mechanism.

Alcohol Drinking↗
PubMed2000

Taurine and ethanol preference: a microdialysis study using Sardinian alcohol-preferring and non-preferring rats.

Recent intracerebral microdialysis studies of different rat brain regions have shown that an acute ethanol injection induced a rapid dose-dependent increase in taurine microdialysate content during the first 60-min period. In taurine-supplemented rats, a reduced aversion for high ethanol doses was observed in a place conditioning paradigm, suggesting that taurine may be implicated in the regulation of some adverse effects of ethanol. The present study compares the effects of acute ethanol injections (1.0 and 2.0 g/kg, i.p.) on taurine nucleus accumbens microdialysate content in Sardinian ethanol-preferring (sP) and Sardinian ethanol-non-preferring (sNP) rats. While neither saline nor 1.0 g/kg ethanol injections had significant effect on taurine microdialysate concentration, 2.0 g/kg ethanol administration induced a rapid and significant increase in taurine microdialysate content in both sP and sNP rats. However, this ethanol-induced taurine release was significantly reduced in sP rats by comparison to sNP rats. As taurine is suggested to be released by brain cells to modulate different ethanol adverse effects, this lower taurine responsiveness to ethanol in sP rats by comparison to both sNP and Wistar rats may be a relevant indicator of reduced ethanol aversive effects in such animals and therefore be related to their higher alcohol consumption.

Alanine↗
PubMed2000

Alpha-melanocyte-stimulating hormone in normal human physiology and disease states.

Over the past two decades, research in animal models has indicated that alpha-melanocyte-stimulating hormone (alpha-MSH) has potent anti-inflammatory properties. Furthermore, recent data show that the peptide has antimicrobial effects and probably contributes to innate immunity. alpha-MSH, which is produced by many extrapituitary human cells, should no longer be considered solely a pituitary hormone; rather, it should be viewed as a ubiquitous modulatory peptide.

Animals↗
PubMed2000

The effects of trauma among kidnap victims in Sardinia, Italy.

BACKGROUND: No study to date has investigated the effects of the trauma of being kidnapped for ransom. In the present study, we aimed to assess the general health status and the presence of post-traumatic stress disorder (PTSD) and major depression (MDD) in a sample of kidnap victims. We also focused attention on dissociative experiences and on the development of the Stockholm syndrome during captivity. METHODS: We investigated the traumatic experiences and reported general health status of 24 kidnap victims using a semistructured interview. The Structured Clinical Interview for DSM-IV was used to assess the presence of PTSD and MDD. The Dissociative Experiences Scale was also administered. RESULTS: The lifetime frequency of PTSD and MDD were 45.9% and 37.5% respectively. The Stockholm syndrome had been present in 50% of the sample during captivity. The presence of PTSD can be predicted by the number of violent experiences, whereas the number of humiliating or deprivation experiences predicts the development of the Stockholm syndrome. Subjects with both PTSD and the Stockholm syndrome reported a greater number of physical complaints at the interview. CONCLUSIONS: There is no significant connection between PTSD and the Stockholm syndrome. Both are indices of the severity of the trauma of being kidnapped, but they are associated with different aspects of the traumatic experience. The presence of both syndromes appears to have a detrimental effect on physical health.

Adult↗
PubMed2000

Dissociation of ethanol and saccharin preference in sP and sNP rats.

BACKGROUND: It has been proposed that ethanol intake and consumption of sweet tasting solutions are positively correlated in rodents. Experiment 1 of the present study investigated whether selectively bred ethanol-preferring (sP) and -nonpreferring (sNP) rats differed, consistently with the above hypothesis, as to saccharin intake and preference. Experiment 2 evaluated whether saccharin addition to the ethanol solution, likely resulting in a highly palatable fluid, would result in an increase in voluntary ethanol intake in sP rats. METHODS: The saccharin solution was offered, in free choice with water, at a fixed concentration of 1 g/liter for 6 consecutive days in Experiment 1A or at ascending concentrations (0.002 to 16.4 g/liter, doubling the concentration every day) in Experiment 1B. In Experiment 2, 1 g/liter saccharin was added to the standard 10% ethanol solution and offered to sP rats in free choice with water for 7 consecutive days. RESULTS: In both Experiments 1A and 1B, sP and sNP rats showed avidity for the saccharin solution with marginal line difference in saccharin intake and preference. In Experiment 2, daily ethanol intake remained stable at baseline levels (6-7 g/kg), irrespective of the saccharin addition to the ethanol solution. CONCLUSIONS: The results of Experiments 1A and 1B suggest that saccharin drinking behavior in sNP rats deviates from the hypothesis that saccharin and ethanol intakes may co-vary; thus, at least in sNP rats, saccharin and ethanol intakes do not appear to be influenced by the same genetic factors. The results of Experiment 2 provide further support to the existence of a central set-point mechanism that regulates daily ethanol intake in sP rats, likely based on the pharmacological effects of ethanol.

Alcohol Drinking↗
PubMed2000

Ability of baclofen in reducing alcohol intake and withdrawal severity: I--Preclinical evidence.

BACKGROUND: The similarities between the pharmacological effects of the gamma-aminobutyric acid receptor agonist, baclofen, and the alcohol-substituting agent, gamma-hydroxybutyric acid, led us to investigate whether baclofen was capable of reducing (a) ethanol withdrawal syndrome in ethanol-dependent rats and (b) voluntary ethanol intake in ethanol-preferring rats. METHODS: In experiment 1, Wistar rats were rendered physically dependent on ethanol by the repeated administration of intoxicating doses of ethanol for 6 consecutive days. Baclofen was acutely administered intraperitoneally at doses of 10, 20, and 40 mg/kg. In experiment 2, baclofen (0, 2.5, 5, and 10 mg/kg, intraperitoneally) was administered once a day for 14 consecutive days to ethanol-preferring sP rats that had continuous access to ethanol (10%, v/v) and water under the two-bottle free choice regimen. RESULTS: In experiment 1, baclofen dose-dependently decreased the intensity of ethanol withdrawal signs; furthermore, 20 mg/kg of baclofen protected from audiogenic seizures in ethanol-withdrawn rats. In experiment 2, baclofen selectively and dose-dependently reduced voluntary ethanol intake; a compensatory increase in water intake left total fluid intake virtually unchanged. CONCLUSIONS: These results are in close agreement with those of a preliminary clinical study and suggest that baclofen may constitute a novel therapeutic agent for alcoholism.

Alcohol Drinking↗
PubMed2000

Ability of baclofen in reducing alcohol craving and intake: II--Preliminary clinical evidence.

BACKGROUND: Accumulating evidence shows the efficacy of the gamma-aminobutyric acid (GABA(B)) receptor agonist baclofen in reducing alcohol intake in rats, but no studies have been performed in alcoholics. In the present preliminary study we investigated the effect of short-term baclofen administration on craving for alcohol, ethanol intake, and abstinence from alcohol in alcoholic individuals. METHODS: Ten male current alcoholic individuals were admitted to the study. Baclofen was orally administered for 4 weeks, at a dose of 15 mg/day refracted in three times per day for the first 3 days, with the dose increased to 30 mg/day for the remaining 27 days. Each subject was checked as an outpatient every week for the 4 weeks; at each visit (T0-T4) craving level was evaluated by the Alcohol Craving Scale (ACS), and abstinence from alcohol was assessed based on the individual's self-evaluation, family member interview, and the main biological markers of alcohol abuse. A self-reported alcohol intake was recorded as the mean number of standard drinks consumed per day. RESULTS: Nine subjects completed the study; of these, two subjects continued to drink alcohol although they substantially reduced their daily drinks in the first week of treatment, whereas seven maintained abstinence throughout the experimental period. Craving was significantly reduced from the first week of the drug administration (p < 0.01) and remained so throughout the entire treatment period. Participants also reported that obsessional thinking about alcohol disappeared. Values of gamma-glutamyltranspeptidase, alanine aminotransferase, and mean cellular volume significantly decreased by the end of the study. Tolerability was fair in all participants; headache, vertigo, nausea, constipation, diarrhea, abdominal pain, hypotension, increased sleepiness, and tiredness were present as side effects in the first stage of the treatment. No participants showed craving for the drug. CONCLUSIONS: With the limitations of the low number of individuals evaluated and the open design, this preliminary clinical study supports the preclinical evidence on the effect of baclofen in reducing alcohol intake. The anticraving properties of the drug suggest a possible role of baclofen in the treatment of individuals with alcohol problems.

Adult↗
PubMed2000

[The use of the biofragmentable ring (BAR-Valtrac) in colon surgery].

BACKGROUND: Clinical results of colic anastomosis using biofragmentable anastomosis ring (BAR-Valtrac) are presented. Such a method showed to be a real alternative technique to the usual ones. METHODS: Eighty-six colic anastomosis using BAR are collected, 76 of which performed as elective surgery and 10 in emergency. The patients were 47 males and 39 females, with a mean age of 64 years. In 63 cases the patients were affected by colic neoplastic disease, in 16 by complicated diverticular disease (stenosis or perforation) and 7 patients had neoplastic disease of other organs involving the colon BAR device was used in 48 colic reconstructions after segmentary resection and in 38 colic reconstructions after left hemicolectomy. In each case 31-34 mm BAR were used. RESULTS: No perioperative death occurred in our series. Only one case (2%) of anastomotic leak was observed, while in 3 cases (4%) intestinal canalization disorders occurred. No problems for ring expulsion occurred in any patient. Three late complications were observed, as three cases of asymptomatic substenosis discovered during instrumental follow-up and spontaneously cleared up. CONCLUSIONS: On the basis of clinical results, and according to those reported in literature BAR anastomosis is considered a safe, feasible and easy technique to perform colic anastomosis, even in emergency, limited to the intraperitoneal tract of the colon.

Adult↗