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Biomedical subjects

G Serra

Publications and source records attributed to G Serra.

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

A randomised control study comparing the Infant Flow Driver with nasal continuous positive airway pressure in preterm infants.

OBJECTIVE: To compare the effectiveness of the Infant Flow Driver (IFD) with single prong nasal continuous positive airway pressure (nCPAP) in preterm neonates affected by respiratory distress syndrome. DESIGN: Randomised controlled study. PATIENTS: Between September 1997 and March 1999, 36 preterm infants who were eligible for CPAP treatment were randomly selected for either nCPAP or IFD and studied prospectively for changes in oxygen requirement and/or respiratory rate. The requirement for mechanical ventilation, complications of treatment, and effects on mid-term outcome were also evaluated. RESULTS: Use of the IFD had a significantly beneficial effect on both oxygen requirement and respiratory rate (p < 0.0001) when compared with nCPAP. Moreover, O(2) requirement and respiratory rate were significantly decreased by four hours (p < 0.001 and p < 0.03 respectively). The probability of remaining supplementary oxygen free over the first 48 hours of treatment was significantly higher in patients treated with the IFD than with nCPAP (p < 0.02). IFD treated patients had a higher success (weaning) rate (94% v 72 %) and shorter duration of treatment (49.3 (31) v 56 (29.7) hours respectively; mean (SD)), although the difference was not significant. CONCLUSIONS: IFD appears to be a feasible device for managing respiratory distress syndrome in preterm infants, and benefits may be had with regard to oxygen requirement and respiratory rate when compared with nCPAP. The trend towards reduced requirement for mechanical ventilation, shorter clinical recovery time, and shorter duration of treatment requires further evaluation in a multicentre randomised clinical trial.

Female↗
PubMed2001

Cerebral hemodynamic response to unpleasant odors in the preterm newborn measured by near-infrared spectroscopy.

Newborn infants in intensive care units are exposed to several unfamiliar smells, mostly related to the nosocomial environment. How the preterm baby perceives these olfactory stimulations remains unclear. Near-infrared spectroscopy can be performed noninvasively above the olfactory cortex to monitor changes of cerebral blood flow as an indicator of cortical activation. The aim of this study was to explore by near-infrared spectroscopy how odorous substances routinely used in the neonatal intensive care unit influence bilateral cortical hemodynamics in the olfactory region of the brains of preterm infants. Specifically, a detergent (Neomidil) and an adhesive remover (Remove) have been tested. Twenty preterm neonates of gestational age 30-37 wk (mean 33.7 +/- 2.3 SD) and postconceptional age 32-37.3 wk (mean 35.5 +/- 2.75 SD) were monitored by near-infrared spectroscopy. Two optode pairs were placed above the anterior orbitofrontal gyri, which is involved in olfactory processing, on each side of the skull. Fifteen babies were exposed to the smell of a disinfectant and five babies to that of a detergent, both applied to small cotton pads. Changes of oxygenated Hb and deoxygenated Hb were recorded before, during, and after a 10-s stimulus. In 17 out of 20 babies, there was a decrease in oxygenated Hb and total Hb after the exposure to the substances. The decrease was significantly greater in the right side than in the left side. This change was different from that observed in our previous study after exposure to colostrum and the pleasant smell of vanilla, which elicited an increase in blood oxygenation in the same region. The biologic significance of this finding is unknown. We conclude that cortical hemodynamic modifications occur in the preterm newborn after exposure to preparations commonly used in the neonatal intensive care unit. A lateralization seems to occur in processing unpleasant olfactory cues.

Cerebrovascular Circulation↗
PubMed2001

Circulating adrenomedullin is increased in preterm newborns developing intraventricular hemorrhage.

Adrenomedullin is a novel vasoactive peptide that participates in cerebral blood flow regulation and circulates in human plasma. To verify whether plasma adrenomedullin is able to identify preterm newborns at risk of intraventricular hemorrhage (IVH), we performed a case-control study. Plasma samples collected within 6 h after birth in 24 preterm newborns who developed IVH, as diagnosed at 72 h, were assessed for adrenomedullin and compared with those obtained from 48 preterm newborns, matched for gestational age, who did not develop IVH. Cerebral ultrasound and Doppler velocimetry waveform patterns in the middle cerebral artery were also recorded at the time of blood sampling. Adrenomedullin blood concentrations and middle cerebral artery pulsatility index values were significantly higher in infants developing IVH (20.1 +/- 4.5 fmol/mL and 1.71 +/- 0.21 fmol/mL, respectively) than in controls (7.5 +/- 3.0 fmol/mL and 1.49 +/- 0.19 fmol/mL, respectively). Adrenomedullin blood concentrations correlated with middle cerebral artery pulsatility index (r = -0.77, p < 0.01) and with the grade of IVH extension (r = 0.83, p < 0.01). This study suggests that adrenomedullin blood concentration might be a promising tool for identifying preterm infants at risk of IVH immediately after birth, when imaging assessment and clinical symptoms of hemorrhage are still silent.

Adrenomedullin↗
PubMed2001

Branchio-Oto-renal syndrome: a report on nine family groups.

This study reviews nine new families with branchio-oto-renal (BOR) syndrome (Online Mendelian Inheritance in Man [OMIM] 113650). Diagnosis was made by studying 10 index cases, and then 22 other previously undetected patients were diagnosed within the nine families. The syndrome consists of conductive, sensorineural, or mixed hearing loss; preauricular pits; structural defects of the outer, middle, or inner ear; renal anomalies; lateral cervical fistulas, cysts, or sinuses; and/or nasolacrimal duct stenosis or fistulas. In our study, all patients first diagnosed in each familial group were recognized on the basis of severe renal anomalies associated with at least one of these symptoms. Our study showed that BOR syndrome is a misdiagnosed disorder, usually recognized in the presence of severe renal failure but often not diagnosed, especially in the adult in the presence of other isolated clinical signs, such as mild branchial or urological anomalies. We stress the meticulous search we performed for renal anomalies and/or hearing loss in all subjects showing minimal signs of branchial defects. BOR syndrome should be suspected in all cases of isolated urological anomalies, even if no other signs of the syndrome are present. After BOR syndrome has been diagnosed in a patient, all family members should be examined for the presence of the syndrome, even if there are only minimal stigmata of the disease.

Branchio-Oto-Renal Syndrome↗
PubMed2000

Early exposure to restraint stress enhances chemical carcinogenesis in rat liver.

This study examines the effect of a stress-associated condition on chemical hepatocarcinogenesis in the rat. Rats were given diethylnitrosamine (200 mg/kg. b.w., i.p.), followed, 1 week later, by three cycles of immobilization at room temperature. Two weeks after the last cycle they were treated according to the resistant hepatocyte protocol. At 4 weeks after selection, mean size of glutathione-S-transferase 7-7 positive foci/nodules was increased in the immobilized group (0.82+/-0.22 vs. 0.25+/-0.04 mm(2) in controls). Furthermore, at the end of 1 year 10/13 animals (77%) developed hepatocellular carcinoma in the former group, while only 6/14 (43%) incidence of cancer was found in controls. These results indicate that exposure to restraint stress early during carcinogenesis enhances the development of chemically-induced hepatocellular carcinoma in the rat.

Animals↗
PubMed2000

The role of dopamine in the mechanism of action of antidepressant drugs.

The present paper reviews evidence on the effect of antidepressant treatments on dopamine transmission. Chronic treatment with antidepressant drugs potentiates the behavioural stimulant responses elicited by the stimulation of dopamine receptors, including reward-related behaviours. Moreover, antidepressants affect dopamine release in several brain areas. The reviewed literature is discussed in terms of the possible mechanisms underlying antidepressant-induced supersensitivity to dopamine-mediated behavioural responses, and of the possible implications for the therapeutic effect of these drugs. It is concluded that the potentiation of dopaminergic neurotransmission induced by chronic antidepressant treatments might contribute to their therapeutic effect.

Animals↗
PubMed2000

Exploratory behaviour and grooming after repeated restraint and chronic mild stress: effect of desipramine.

In a previous study, we have recently shown that chronic treatment with desipramine either reduced or potentiated the locomotor response to the dopamine D(2)-like receptor agonist quinpirole, a behavioural response mediated by the mesolimbic dopamine system, depending on whether the animals were subjected, respectively, to repeated restraint or to chronic mild stress (different stressors randomly presented). In this study, we examined the interaction between prolonged exposure to either repeated restraint stress or chronic mild stress with the chronic administration of the antidepressant desipramine on two spontaneous behaviours, in which an involvement of the mesolimbic dopamine system has been suggested: novelty-induced exploratory activity and grooming. Exploratory activity in the open field was reduced by chronic mild stress regardless of the drug treatment, while it was not influenced by restraint stress. Desipramine reduced exploratory activity in rats subjected to restraint stress. Restraint stress increased grooming and desipramine reversed this effect, while increasing grooming in the chronic mild stress group. These findings suggest that antidepressants exert their effect by opposing the modifications induced by stress. The available experimental evidence is consistent with the hypothesis that an important role in the observed behavioural changes is played by the mesolimbic dopamine system.

Animals↗
PubMed2000

Chronic lithium chloride fails to prevent imipramine-induced sensitization to the dopamine D(2)-like receptor agonist quinpirole.

Lithium salts, an effective antimanic treatment, are able to prevent the development of the dopaminergic behavioural supersensitivity induced by chronic treatment with neuroleptics, by denervation of the dopaminergic terminal fields and by rapid eye movements (REM) sleep deprivation, which is considered a model of mania. We have studied the effect of a lithium (LiCl) diet, inducing a lithium serum level in the range of therapeutic efficacy, on the development of the supersensitivity to the locomotor effect of the dopamine D(2)-like receptor agonist, quinpirole, induced by chronic treatment with the antidepressant drug, imipramine. The results show that lithium is not able to prevent the development of such behavioural supersensitivity. The present data suggest that antidepressant-induced dopaminergic supersensitivity might provide a useful model of those manic states induced by (or subsequent to) antidepressant treatments. Moreover, the finding is consistent with the view that antidepressant-induced dopaminergic supersensitivity might play a role in the therapeutic effect of these drugs (which is known to be augmented by lithium, and not antagonised). Finally, the results show that the dopaminergic supersensitivity induced by imipramine is qualitatively different from that induced by neuroleptics or denervation of the dopaminergic terminal fields.

Analysis of Variance↗
PubMed2000

A prospective naturalistic study of 326 panic-agoraphobic patients treated with antidepressants.

OBJECTIVE: How far the results of randomized controlled studies apply to everyday care cannot be judged without regular measurements of outcomes in daily practice. We report on systematic data from a 3-year naturalistic prospective study on panic disorder-agoraphobic (PDA) patients treated with antidepressants in a setting of routine clinical practice. Our aim is to describe the evolution of PDA in relation to the treatments employed, and to explore demographic and clinical characteristics that might be predictive of outcome. METHODS: 326 DSM-III-R PDA patients treated with antidepressants in a setting of routine clinical practice were included in a 3-year naturalistic prospective study. We utilized structured and semi-structures instruments, including the Structured Clinical Interview for Diagnosis and the Longitudinal Interview Follow-up Examination. The main antidepressants used were imipramine (39%), clomipramine (28.5%) and paroxetine (23.3%); only 9% of patients received other antidepressants. RESULTS: 147 patients (45.1%) stayed on medication throughout the entire period of the follow-up. Of those who interrupted the treatment, 38% stayed in remission. The probability of achieving at least one remission during the 3-year follow-up period was 96.5% for PD and 95.9% for Agoraphobia. Relapses after a period of at least 2 months of complete remission were also common, and the probability of presenting at least one relapse during the 3-years follow-up period was 67.1% for PD and 39% for Agoraphobia. The longest period of remission of PD is associated with low severity, medium-lasting course in patients with an onset of the illness in young adulthood. Less severe agoraphobia associated with moderately severe panic attacks appears to confer a better control of phobic behavior. All three major drugs were reasonably well tolerated (only 9% dropped out because of side effects), with sexual dysfunction and increased appetite being the most common side effects at the last evaluation; in the first phase of the treatment anticholinergic effects and jitteriness were more common with TCAs. CONCLUSION: Both classical antidepressants and paroxetine emerge as a useful treatment in the long-term management of PDA; paroxetine appears particularly useful in PDA patients because it was significantly less likely to induce jitteriness, thereby reducing barriers to compliance.

Adult↗
PubMed2000

Adequacy in pre-dilution haemofiltration: Kt/V or infusion volume? The Sardinian Collaborative Study Group on Haemofiltration On-line.

Kt/V is the main index of adequacy for diffusive and diffusive convective methods of extracorporeal depuration, yet there exists no universally acceptable validation of an adequacy index for the solely convective methods such as haemofiltration (HF). The aim of the present study is to analyse which of the parameters of adequacy used in two multicentre HF studies, Kt/V for urea or infusion volume, correlate best with nutritional parameters and can therefore be utilized for the evaluation of treatment dose in on-line pre-dilution HF. Twenty-three clinically stable patients were enrolled in the first study [3 months of haemodialysis (HD)+ 3 months of HF]. In the second study, 24 stable patients were studied in three phases: 6 months in HF, 6 months in HD and a further 6 months in HF; in this study, a target of Kt/V= 1.2 in all three periods was preestablished: 15 patients completed the full study. In both studies, we utilized the same monitor (AK 100/200 Ultra, Gambro), the same membrane (polyamide) and the same on-line prepared ultrapure dialysis fluid and sterile infusion solution. In both studies, we ensured that HF fulfilled the following parameters of adequacy: urea kinetics, cardiovascular and blood pressure stability (better in HF than in HD), common haematochemical and nutritional parameters, reduction in beta2-microglobulin levels, a good intra- and extra-session clinical outcome, and a good quality of life with morbidity and mortality rates no different from those of HD. HF proved to be an efficacious method of ensuring adequate depuration and a good quality of life for uraemic patients. We have shown that in longer periods of HF, a notable correlation between Kt/V and normalized protein catabolic rate (nPCR) and an equally good correlation between total ultrafiltration (UF)/dry weight ratio and nPCR could be achieved. In both studies, the patients showed a good level of epuration adequacy when total UF per session was at least 1.3 times the dry body weight. The total UF/body weight ratio thus seems to be an easy method in HF because of its greater ease of predictability and measurement, also when it is used independently of the Kt/V index.

Adult↗
PubMed2000

Different effect of desipramine on locomotor activity in quinpirole-treated rats after repeated restraint and chronic mild stress.

We have studied the effect of chronic treatment with the tricyclic antidepressant drug desipramine on locomotor activity in rats challenged with the administration of the D2-like dopamine agonist quinpirole, after prolonged exposure to two different stress regimens, repeated restraint stress and chronic mild stress (different stressors randomly presented). These stress schedules have been previously reported to influence in opposite ways the sensitivity to the locomotor response mediated by the stimulation of mesolimbic dopamine receptors. In particular, repeated restraint has been reported to induce an increased response to the locomotor effect of amphetamine, while chronic mild stress has been reported to induce a decreased locomotor response to quinpirole. In the present study, repeated restraint stress failed to influence the locomotor activity after challenge with quinpirole, while chronic mild stress reduced this response. Chronic treatment with desipramine failed to influence this response in the control group, but exerted opposite effects in the two stressed groups. In particular, chronic desipramine reduced locomotor activity in quinpirole-treated rats in the restraint stress group, and increased it in the chronic mild stress group, thus preventing the subsensitivity induced by this stress regimen. The present results, taken together with results from earlier studies, are consistent with the hypothesis that the effect of antidepressants on the sensitivity of the mesolimbic dopamine receptors mediating the locomotor behavioural response tends to be opposite with respect to that exerted by stress, regardless of its direction. However, since we failed to show an increased locomotor activity after quinpirole challenge in the repeated restraint group, this hypothesis remains to be demonstrated. The two stress schedules reduced body weight gain in a similar way, therefore their different effects do not seem to be due to a difference in stress severity. Thus, the observation that both stress schedules reduced body weight gain in a similar way, but only chronic mild stress reduced the sensitivity to the locomotor response to quinpirole, shows that this effect is not an artefact of body weight decrease.

Animals↗
PubMed2000

Activation of olfactory cortex in newborn infants after odor stimulation: a functional near-infrared spectroscopy study.

In mammals, perception of smells during the first hours of life is an essential prerequisite for adaptation of the newborn to the new extrauterine world. Functional magnetic resonance studies have shown that olfactory impression is processed in the lateral and anterior orbito-frontal gyri of the frontal lobe. Near-infrared spectroscopy (NIRS) can detect changes in oxygenated [Hb O2], and deoxygenated [Hb H] Hb during cortical activation. The aim of this study was to assess by NIRS olfactory cortex activity in newborn infants receiving olfactory stimuli. Twelve males and 11 females were studied when awake at 6 h to 8 d after birth. NIRS monitoring was carried out using two optodes placed above the left anterior orbito-frontal gyri. Each newborn was exposed for 30 s to two different smell stimuli-mother's colostrum and vanilla-and to a negative control, distilled water. Changes in Hb concentration were measured over the orbitofrontal region. During exposure to vanilla, [Hb O2] increased significantly over the left orbito-frontal area in all babies. The magnitude of the [Hb O2] increase over the illuminated region during colostrum exposure was inversely related to postnatal age. We conclude that monitoring Hb changes by NIRS can be valuable in assessing olfactory responsiveness in infants.

Aging↗
PubMed2000

The costs of pharmacological treatment for major depression. The Italian Prospective Multicentre Observational Incidence-Based Study.

OBJECTIVE: To describe the pharmacological treatment for major depression under the conditions of routine Italian public mental health facilities, assess its costs, and study its main predictors according to a societal perspective. DESIGN: This was a prospective multicentre observational study designed to evaluate the economics of treatment of major depression using a specifically designed 65-item questionnaire. Data on drug consumption were collected in a section of the questionnaire and are presented here. PATIENTS AND PARTICIPANTS: 60 mental health facilities were selected and 556 patients were enrolled and followed up for 15 months. RESULTS: Pharmacological treatment appears to be the most common treatment for major depression. 98% of patients were prescribed an antidepressant. Selective serotonin reuptake inhibitors (SSRIs) were the most prescribed antidepressants. Patients treated with SSRIs suffered from less severe depression than those treated with tricyclic antidepressants. Benzodiazepines were prescribed for 84% of patients enrolled. The total drug cost was 1,120,000 Italian lire ($US707) per patient (1995 values). Less than 20% of this cost was borne by the Italian National Health Service, as the majority of drugs used were not reimbursed. CONCLUSIONS: The costs of the most widespread approach to treating major depression (pharmacological treatment) are not currently covered by the Italian National Health Service. Prescribing of drugs seems to diverge from the standards of treatment indicated by the Italian Drug Committee.

Adult↗
PubMed2000

[2,3 diphosphoglycerate in preterm newborns].

BACKGROUND: It has been largely shown that during the first month of life, in the preterm neonate Hb levels and Hct percentages rapidly decrease, high HbF concentration persists and a high oxygen affinity occurs. Data are needed to establish the level at which 2,3 dyphosphoglycerate (2,3 DPG) interacts with the regulation of oxygen affinity. SUBJECTS AND METHODS: 24 samples, from eight uncomplicated preterm newborns (34.1 +/- 1.83 GW, 1869 +/- +/- 291 BW) obtained at the same time as those required for the clinical management of the infants, were collected on the 2nd, 7th and 14th day of life. Blood gases, total hemoglobin and hematocrit were obtained from 0.3 ml arterialised capillary blood. Assays of 2,3 DPG were made separately on 0.4 ml venous blood. RESULTS: As expected tHb concentration and Hct percentages significantly decreased from day 2 to day 14 in all eight cases. On the contrary 2,3 DPG and p50 values remained stable. Subsequently throughout the study period all neonates had an increased 2,3 DPG/Hb ratio that was significantly related with p50 at standard conditions (p < 0.05). CONCLUSIONS: Stable 2,3 DPG concentrations during all study period have been detected. The subsequent significant increased 2.3 DPG/Hb, ratio related to increased p50 values, could have a key role in a physiological mechanism aimed to ensure adequate oxygen delivery to the tissues and to counteract the higher oxygen affinity of fetal hemoglobin. A wider sample is needed to validate this hypothesis.

2,3-Diphosphoglycerate↗