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Biomedical subjects

P Bo

Publications and source records attributed to P Bo.

At least 19 recordsLinked to original sources
PubMed2004

Pro-oxidant activity and methionine metabolism in chronic alcohol abusers: relationship to alcohol withdrawal and folate administration.

AIM: The aim of this study was to investigate whether alcohol withdrawal and folate administration could play a role on redox balance and metionine metabolism in heavy drinkers. METHODS: The derivatives of reactive oxygen metabolites (d-ROMs), homocysteine, total thiols, vitamin B12 and folate were evaluated in a selected group of 40 consecutive chronic alcohol abusers by comparison with 44 healthy moderate drinkers, as controls. RESULTS: Before alcohol withdrawal, d-ROMs were significantly higher (p<0.0001) in heavy drinkers than in controls: 368.5 (254.8-718.6) U.CARR vs 245 (200.7-360) U.CARR, respectively, median with range. Plasma homocysteine were significantly higher in alcoholics than in moderate drinkers (p<0.0001): 18 (9.5-82.2) micromol/L vs 9.1 (4.9-19.6) micromol/L, respectively. Heavy drinkers also exhibited higher serum thiols than moderate drinkers (p<0.003): 605.8 (448.2-717.7) micromol/L vs 554.8 (508.3-658.4) micromol/L, respectively. The patients showed lower plasma folate than controls (p<0.0001): 4.1 (1.9-9.7) ng/mL vs 8.8 (5.0-8.4) ng/mL, respectively, but similar vitamin B12 levels: 487 (299-786) pg/mL 621 (243-894) pg/mL. A negative correlation between homocysteine and folate was observed before withdrawal in alcoholics (r=-0.4546, p<0.038). Both serum thiols (549.7 micromol/L, range 402.4-616.6 micromol/L) and homocysteinemia (6.6 micromol/L, range 2.9-18.5 micromol/L) were significantly decreased (p<0.0001 and p<0.022, respectively) after a week of alcohol withdrawal and folate administration. CONCLUSION: Our findings show that both enhanced pro-oxidant activity and a derangement of methionine metabolism can be observed in heavy drinkers before alcohol withdrawal and folate administration. Furthermore, folate seems to be a strong determinant of both plasma homocysteine and thiol concentrations.

Adult↗
PubMed2002

Chronic alcoholism and the frontal lobe: which executive functions are imparied?

OBJECTIVE: Over the last decade, various hypotheses have been advanced concerning the cognitive functions affected by chronic alcoholism. The aim of this study was to identify the pattern of executive function impairment in chronic alcoholism, shedding light on possible differences between specific functions related to the frontal lobe. METHODS: Twenty-two male alcoholics and 22 controls, matched for age, educational level and IQ, were enrolled in the study. MMPI and a battery of neuropsychological tests [i.e. digit symbol, trail making test, Stroop test, digit cancellation test, Wisconsin card sorting test (WCST), simple and choice reaction times] for assessing frontal lobe functioning were administered. RESULTS: The alcoholics were found to be impaired in a wide range of executive domains, with the exception of the Stroop test, which nevertheless showed a trend towards statistically significant differences between patients and controls. CONCLUSION: With the exception of aggression - our subjects did not have high aggression scale scores - the 'frontal lobe hypothesis', according to which alcoholic patients are impaired on function tests related to the frontal lobe, was therefore confirmed in our sample.

Adult↗
PubMed2001

Effects of moderate and high doses of alcohol on carotid atherogenesis.

The role of alcohol consumption on pathophysiology of atherosclerosis is not completely well established. Past studies were conducted with different methodological approaches, sometimes leading to opposing conclusions. The aim of this study was to determine the weight of alcohol intake on carotid atherosclerosis in a group of subjects asymptomatic for cardio-cerebrovascular diseases. They were examined by ultrasonographic assessment during the period 1993 through 1997. Common risk factors of atherosclerosis and drinking habit were assessed by a standardized questionnaire. In this survey we confirm the J-shaped relationship between atherosclerosis and alcohol consumption. The effect of alcohol intake is more evident if we consider the presence of multiple internal carotid stenosis, or those greater than 25%, as outcome variables. These effects are independent from the other risk factors included in logistic regression paradigms (age, arterial hypertension, dyslipidemia, diabetes mellitus, family history of cardio-cerebrovascular disease, smoking and social status). Our study supported that a high level of alcohol intake plays a role as an independent factor in carotid atherogenesis.

Adult↗
PubMed2001

Oxidative stress and a thrombophilic condition in alcoholics without severe liver disease.

BACKGROUND AND OBJECTIVES: The degree of oxidative stress and its association with a thrombophilic condition, if any, were investigated in alcoholics before the onset of severe liver disease. DESIGN AND METHODS: Reactive oxygen species and total antioxidant capacity were evaluated using two new kinetic spectrophotometric methods in a selected group of 45 consecutive chronic alcohol abusers and 42 apparently healthy moderate drinkers, used as controls. The hemostatic system was explored by detecting the plasma levels of prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin complexes (TAT) with enzyme-linked immunosorbent assays, while D-dimer plasma levels were measured with a turbidimetric immunoassay. RESULTS: Reactive oxygen species were significantly higher (p<0.001) in heavy drinkers than in controls: 328.1 (143.4-847.2) U.CARR vs 250 (200.7-366.8) U.CARR, respectively. The total antioxidant capacity was similar in chronic alcohol abusers and in moderate drinkers: 360.2 (336.8-374.4) microMol HClO/mL vs 369 (362-378.4) microMol HClO/mL, respectively. All molecular markers of hemostatic system activation were significantly increased in chronic alcohol abusers in comparison with those in moderate drinkers, as follows: TAT: 2.5 (1.4-13) microg/L vs 1.5 (1-4.1) mocrog/L, respectively (p<0.001); F1+2: 1.7 (0.5-5.2) nMol/L vs 0.9 (0.4-1.1) nMol/L, respectively (p<0.01); D-dimer: 235.5 (208-462) ng/mL vs 163.5 (71-233) ng/mL, respectively (p<0.001). INTERPRETATION AND CONCLUSIONS: Our results suggest that oxidative stress and a thrombophilic condition can be observed in heavy drinkers without severe liver disease. The new test available for measuring reactive oxygen species in serum proved to be reliable and useful as an early marker of tissue damage.

Adult↗
PubMed2000

Asbestos body burden in decomposed human lungs.

The authors discuss the influence of postmortem tissue decomposition on the lung asbestos body (AB) burden, with the aim of evaluating the reliability of data obtained from autopsies performed for medicolegal purposes several months after deaths in possible connection with asbestos-related pathology. Eight autopsy cases were selected, each one with occupational exposure considered very probable on the basis of the history or pathologic findings. In each case the AB concentrations were assessed soon after death in one lung and after periods of 1 to 18 months in the others, which had been stored in sealed containers without fixation. AB concentrations consistently decreased with time in rotten lungs. The counts in some cases became negative a few months after death, even in cases with very high AB counts at first examination. It may be reasonably inferred that, in putrefied lungs from corpses exhumed after months of internment, the counts in digested tissues and the screening of histologic sections for AB may give false-negative results.

Air Pollutants, Occupational↗
PubMed1999

Role of iron in asbestos-body-induced oxidant radical generation.

Asbestos bodies (AB) were harvested from human lung tissue digests and isolated from uncoated asbestos fibers. Samples containing 1000 AB were added to a reactive solution to investigate the ability of AB to oxidize deoxy-D-ribose and generate reactive oxygen species (ROS) in the presence of ascorbate and hydrogen peroxide as determined by formation of thiobarbituric acid (TBA)-reactive products. Three types of asbestos fibers were tested for comparison, since they are known to be able to produce ROS. The absorbance values measured with 1000 AB were significantly higher than those observed with 1000 fibers of the three types of asbestos. Since in our reaction system the only source of transition metals was the iron-rich AB, data suggest iron derived from the ferritin coating of AB was involved in oxidant generation. Addition of iron to AB enhanced TBA-reactive product formation, while chelation of Fe with deferoxamine reduced this reaction. Hydroxyl radical scavengers 1,3-dimethyl-2-thiourea (DMTU) and mannitol (MN) also effectively blocked TBA-reactive product generation. Data indicate the importance of Fe in AB-induced oxidant damage. With the addition of polymorphonuclear leukocytes (PMN) to AB, incubation in the reactive solution gave very high amounts of TBA-reactive products, but using a reactive solution devoid of ascorbate, very low amounts of TBA-reactive products were generated. In the latter condition, the superoxide of cell membranes probably reduced and removed iron from AB-coating ferritin, but less effectively than ascorbate. Further after the possible reoxidation of Fe2+, Fe3+ could be coordinated by lactoferrin. Since such availability of reductant is never approached in living systems, the iron in the AB coating is unlikely to function as a catalyst of Fenton-type reactions in vivo.

Asbestos↗
PubMed1999

Cognitive impairment and cerebral atrophy in "heavy drinkers".

1. Aim of the work was to verify the following three hypotheses in alcoholics: a) right hemisphere; b) diffuse brain deficit; c) anterior brain deficit, by means of a neuropsychological and a neuroradiological assessment. 2. 15 alcoholic right-hand male subjects and 15 matched controls were enrolled in the study. 3. Specifically designed neuropsychological testing was performed to investigate logical abilities, selective attention and memory. 4. Neurological investigation was performed by a standard CT scan to assess the degree and localization of brain damage. 5. Alcoholics performed worse than controls on some neuropsychological tests, i.e. Attention Matrices Test, Verbal Judgement Test, Forward Digit Span, Story Recall and Remote Memory Test. The analysis of variance adjusted by the attentional score showed no significant differences between alcoholics and controls. 6. Neuroradiological data showed a preeminent and a more frequent atrophy of the frontal region. 7. No correlations emerged between neuropsychological and neuroradiological data. 8. In conclusion, the hypothesis of anterior brain deficit seems to be confirmed by our study.

Adult↗
PubMed1999

Partial left ventriculectomy for the treatment of end-stage dilated cardiomyopathy.

OBJECTIVE: To report our initial experience of the first 5 cases of partial left ventriculectomy (PLV or Batista operation), a new surgical therapy for treatment of end-stage dilated cardiomyopathy in China. METHODS: From April to August 1998, 5 patients with idiopathic dilated cardiomyopathy received PLV at Anzhen Hospital. The mean age of the patients was 48.4 years (range: 42 to 53 years). Three patients were in New York Heart Association (NYHA) class III and 2 in class IV. All patients had mitral valve insufficiency (3 moderate and 2 severe) and 1 had severe tricuspid valve insufficiency in addition preoperatively. Cardiopulmonary bypass and cardiac arrest with cold blood cardioplegia were used in all patients. The average weight of the resected left ventricle muscle was 46.3 g. All patients underwent mitral annuloplasty and 1 plus tricuspid annuloplasty (De Vega). RESULTS: Echocardiography demonstrated a significant decrease in left ventricular diastolic diameter (8.4 +/- 1.1 cm to 5.4 +/- 0.4 cm, P < 0.01) and an increase in ejection fraction (17.78% +/- 6.26% to 34.82% +/- 3.18%, P < 0.025). One patient died of heart failure on the 6th postoperative day. The mean follow-up period of the 4 discharged patients were 4 months (from 3 to 6 months). One were in NYHA class I and 3 in class II; all had a normal life. CONCLUSION: Batista operation is a new and valuable alternative of the surgical treatment for end-stage dilated cardiomyopathy and the long-term results need further studies.

Adult↗
PubMed1998

The effects of flumazenil on focal, electroinduced after-discharge in rabbits.

1. The anticonvulsive efficacy of flumazenil 10 mg/kg i.v., a BDZ antagonist, was studied in two models of experimental epilepsy electrically induced. 2. The EEG after-discharge, which was induced by the electrical stimulation of selected brain regions [(notably the dorsal hippocampus (Hip) and the amygdala (CAm)] was evaluated in rabbits pre- and post-drug administration. 3. In the animals submitted to electrical stimulation of the amygdala, flumazenil exerted a protective action, thereby inducing an increase in the after-discharge threshold and/or a decrease in after-discharge duration. 4. In the animals submitted to electrical stimulation of the hippocampus, flumazenil did not induced changes statistically significant. 5. Finally, the paper discusses the two possible mechanisms of action of flumazenil (a "per se" partial BDZ activity and/or a BDZ agonistic activity, which displaces the inverse agonist-like ligand) and the differencies in GABA distribution in the hippocampus and the amygdala.

Amygdala↗
PubMed1996

Topical cyclosporine inhibits mast cell-mediated conjunctivitis.

PURPOSE: Allergic conjunctivitis is a common condition caused by a mast cell-mediated hypersensitivity reaction to immunoglobulin E-bound allergens. The purpose of this study was to investigate the effect of topical cyclosporine A on the development of mast cell-mediated conjunctivitis in mice. METHODS: Allergic conjunctivitis was induced in C57BL/6 mice by topical applications of compound 48/80, a mast cell degranulating agent. In two separate experiments, mice were treated with topical cyclosporine A (0.05%, 0.2%, or 0.4%), prednisolone acetate 1%, or phosphate-buffered saline. Twenty-four hours after compound 48/80 instillation, the number of neutrophils, eosinophils, lymphocytes, macrophages, and the number of preserved goblet cells and undegranulated mast cells in the conjunctiva were counted by a masked observer. RESULTS: In both experiments, treatment with all three doses of cyclosporine A resulted in a statistically significant reduction in the number of infiltrating neutrophils and eosinophils compared to saline-treated controls. There was no significant difference in the treatment effect of cyclosporine and prednisolone acetate. In addition, there was increased preservation of goblet cells in the cyclosporine A-treated animals. Immunohistochemical staining showed a reduction in infiltrating lymphocytes and a smaller reduction in infiltrating macrophages in animals treated with cyclosporine compared to saline-treated controls. CONCLUSIONS: Topical cyclosporine A was effective in inhibiting the development of mast cell-mediated allergic conjunctivitis in mice. This study suggests that topical cyclosporine A may be effective in treating allergic conjunctivitis in humans.

Administration, Topical↗
PubMed1996

Laboratory evaluation on the toxic effects of bednets impregnated with permethrin against malaria mosquitos.

In the laboratory, bednets impregnated with 250mg ai/m2 and 500mg ai/m2 permethrin caused respectively the mean mortalities of 86.6% within 13 months and 87.2% within 17 months on laboratory-bred An. sinensis, while they caused average mortalities of 58.3% within 4 months and 73.8% within 10 months on An. dirus respectively. The bioassay results of KT50 and LT50 on the two species showed that KT50 is shorter than LT50 after exposure to the treated bednets. The ratio is 1:2.16 - 1:3.05. It was observed Anopheles had obviously secondary knocked down after exposure to the treated bednets and there is obvious resurgent after Anopheles have been knocked down. When the temperature goes up the resurgence gets shorter, the resurgence rate gets higher and the mortality gets lower. It showed that permethrin has stronger knocking down effect than killing effect.

Animals↗
PubMed1995

Role of dopamine D-1 and D-2 antagonists in a model of focal epilepsy induced by electrical stimulation of hippocampus and amygdala in the rabbit.

1. The differential role played by blockade of D-1 or D-2 dopamine receptors in mechanisms underlying seizures was studied in a model of EEG after-discharge induced by electrical stimulation of selective brain regions (dorsal hippocampus and amygdala) in the rabbit. 2. The D-2 antagonist haloperidol (1 mg/Kg) increased significantly after-discharge duration after stimulation of either hippocampus or amygdala and lowered after-discharge threshold in few animals. 3. The D-1 antagonist SCH 23390 (0.3 mg/Kg) caused no changes following stimulation of amygdala and reduced after-discharge duration when hippocampus was stimulated. 4. Haloperidol exerted a proconvulsant action in this experimental model, having a clearer influence on D-2 receptors. SCH 23390 had no effect on amygdala whereas it exerted protection on the hippocampus. 5. The present data suggest that D-1 and D-2 receptors have different roles in generating and spreading the epileptic activity.

Amygdala↗
PubMed1995

Familial hemiplegic migraine versus migraine with prolonged aura: an uncertain diagnosis in a family report.

Four of five members of a family complained of repeated attacks of hemiplegic migraine, migraine with aura of different types, or migraine without aura. The hemiplegia always outlasted the headache and was often accompanied by altered consciousness, aphasia, and, in one patient, coma; in this latter patient, the ictal EEG, recorded during two attacks, showed delta activity in the hemisphere contralateral to the hemiplegia. At least 2 months after their latest attacks, three patients showed dyscalculia, attentional disturbances, and impaired long-term verbal memory on neuropsychologic assessment. There were no cognitive disturbances in the unaffected relative. The severity of cognitive impairment appears to be correlated with migraine history. We attempt to classify these cases according to the criteria of the International Headache Society.

Adult↗
PubMed1993

Eegraphic and behavioural effects of ondansetron, a 5HT3 antagonist, in rabbits.

1. EEGraphic and behavioural effects of ondansetron, a 5HT3 antagonist, have been studied in the rabbit. Subsequently we tested the neurophysiological and behavioural interactions between ondansetron and L-5-HTP induced serotonergic syndrome. 2. The drug produced a dose-dependent (0.001, 0.01, 0.1 mg/kg i.v.) increase in the cortical power density spectrum, particularly in the range of the lowest frequencies bands. This effect is expression of cortical synchronization. 3. The lowest and mild dose, but not the highest, failed to produce behavioural sedation and to inhibit the arousal induced by vibroacustical stimulation. 4. L-5-HTP (10 mg/kg i.v.) administration generated a typical EEGraphic-behavioural pattern characterized by a decrease of cortical power spectrum density and stereotyped movements. The EEGraphic effects were significantly suppressed by administration of mild and higher doses of ondansetron, while the behavioural effects were inhibited by all doses tested. 5. It is concluded that ondansetron acts with considerably efficacy on central nervous system. The administration of low and mild doses shows a singular dissociation between EEGraphic and behavioural actions. The inhibition of the L-5-HTP behavioural syndrome by ondansetron suggests that this drug acts on behaviour only when there is an altered physiological pattern.

5-Hydroxytryptophan↗
PubMed1993

Early effects of GM1 in experimental cerebral focal ischemia in rabbits.

This study aimed to investigate the effects of monosialoganglioside (GM1) when administered early in a model of cerebral focal ischemia, in the rabbit. The statistical evaluation of the electroencephalographic changes (quantified EEG analysis, QEEG) due to the ischemic event showed that the early treatment (1-3-24 h) with GM1 reduced the EEgraphic pattern typical of this model of cerebral ischemia. Considering the observation period, we hypothesized that it was due to the formation of an oedema of a lesser degree compared to the untreated group. Particularly, we did not obtain the increase in delta activity on the contralateral hemisphere, which we thought was expression of the diaschisi phenomenon.

Acute Disease↗