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Biomedical subjects

P Marraccini

Publications and source records attributed to P Marraccini.

At least 73 records · Page 4Linked to original sources
PubMed1988

Electrocardiographic manifestations and in-hospital prognosis of transient acute myocardial ischemia at rest.

From January 1970 to June 1985, transient electrocardiographic changes at rest were documented in 652 patients admitted to our coronary care unit. Patients were stratified according to the type of electrocardiographic alteration at rest: 295 had ST-segment elevation (group 1), 106 T-wave changes (group 2) and 251 ST-segment depression (group 3). Patients in group 3, compared with groups 1 and 2, were more likely to have symptoms of coronary artery disease dating back many years (p less than 0.01 and p less than 0.01, respectively), a previous myocardial infarction (p less than 0.05 and difference not significant), a positive exercise test (p less than 0.01 and p less than 0.01), transient ST-T changes occurring in a higher number of electrocardiographic leads (p less than 0.01 and p less than 0.01), multivessel disease (p less than 0.001 and p less than 0.01) and poor ventricular function (p less than 0.01 and p less than 0.05). Despite these differences, the occurrence of acute myocardial infarction and cardiac death during hospitalization was much more frequent in group 1 compared with groups 2 (p less than 0.02) and 3 (p less than 0.05). However, death occurred in those patients who had poor ventricular function and severe atherosclerosis. A greater susceptibility of group 1 patients to severe vasoconstriction documented by the ergonovine test and by the occurrence of spontaneous spasm seems to account for different in-hospital outcome.

Adult↗
PubMed1988

The basal electrocardiogram and the exercise stress test in assessing prognosis in patients with unstable angina.

The purpose of this study was to evaluate the prognostic usefulness of basal electrocardiogram and exercise stress test in 374 patients with unstable angina submitted to coronary angiography during the same hospitalization period. After stabilization of symptoms by medical therapy, patients were subdivided into four groups according to the ECG and stress test: Group 1 (54 patients with normal ECG and exercise stress test negative for ischaemia); Group 2 (86 patients with normal ECG and exercise stress test positive for ischaemia); Group 3 (59 patients with abnormal ECG and exercise stress test negative for ischaemia); Group 4 (175 patients with abnormal ECG and exercise stress test positive for ischaemia). The severity of coronary atherosclerosis and impairment of left ventricular function increased progressively from Group 1 to 4, although differences in ventricular function were not significant between Groups 2 and 3. When discharged, patients were treated with verapamil and nitrates and followed for a period ranging from 1 to 8 years; during follow-up, only one patient of Group 1 underwent coronary bypass surgery, compared to 22, 7 and 46 patients in Groups 2, 3 and 4, respectively. The eight-year survival rate in the four groups (1-4) was 100%, 97%, 88% and 70%, respectively. Statistically significant differences were observed between Groups 1 and 3, 1 and 4, 2 and 4, and 3 and 4. Thus, the ECG and exercise stress test allow a population of patients with unstable angina to be selected (Group 1), having excellent long-term prognosis. These patients could avoid angiography, thereby reducing hospital costs, without compromising their health.

Adult↗
PubMed1988

Short term reproducibility of exercise testing in patients with ST segment elevation and different responses to the dipyridamole test.

The short term reproducibility of exercise testing in 25 patients who had exercise induced ST segment elevation without baseline regional asynergy or a previous myocardial infarction, who had different responses to the dipyridamole test, was assessed. The patients performed a dipyridamole echocardiography test and a second exercise stress test. All underwent coronary arteriography. Seventeen patients had transient regional asynergy after dipyridamole (group 1) and either ST segment elevation (14 patients) or depression (three patients); a second group of eight had no asynergy and no electrocardiographic changes (group 2). The repeated exercise stress test was positive in 16 of the 17 patients of group 1 (11 with ST elevation and five with ST depression) and in two patients of group 2 (both had ST depression and one had coronary artery disease). The dipyridamole echocardiography test was positive in 17 of the 19 patients with coronary artery disease and was negative in all six patients without coronary artery disease. The repeated exercise stress test was positive in 17 of the 19 patients with coronary artery disease and in one patient without. The dipyridamole echocardiography test and a repeated exercise stress test, but not a single exercise stress test, identified coronary artery disease causing exercise induced ST segment elevation.

Adult↗
PubMed1988

[Styrene-induced occupational asthma and rhinitis].

Styrene is an aromatic compound widely used in the production of plastic polymers and rubbers. Studies of the effect of styrene on the respiratory tract are scarce. We describe three cases of occupational asthma and one case of occupational rhinitis due to styrene, which have been recently observed in our center. There is evidence that styrene can be a primary cause of occupational asthma and rhinitis. The mechanisms of action are unknown. Our findings suggest the need for preventive strategies for styrene exposed workers.

Adult↗
PubMed1987

Dipyridamole-echocardiography test as a clue for assessing the organic 'ceiling' of individual coronary reserve.

Twenty-four patients with a history of effort angina, a positive exercise stress test (EST) and coronary artery disease were enrolled in the study; 12 patients had a positive dipyridamole-echocardiography test (DET) and 12 had a negative DET. Each patient performed a total of 4 ESTs in the absence of therapy on two successive days; for each test the rate-pressure product (RPP), an established index of myocardial oxygen demand, was measured at the onset of ischaemia (ST depression greater than 0.15 mV) or at the peak of maximal exercise (if a repeated EST was negative). Taking into account the lowest of the 4 RPP values (X 1/100) in each patient, there was no significant difference between DET-negatives and DET-positives (185.2 +/- 49.3 vs 157.4 +/- 32.4). Conversely, when considering the highest of the 4 RPP values in each patient, there was a significant difference between DET-negatives and DET-positives (280.3 +/- 63.9 vs 183.3 +/- 37.0; p less than 0.01). Thus, DET may provide a clinically useful tool for assessing in the individual the organic 'ceiling' of coronary reserve, by eliminating the variability in coronary tone, which may affect EST reproducibility and the correct evaluation of the impairment of organic coronary reserve.

Adult↗
PubMed1987

[Anesthetics vapors and gases and health hazards: results of an environmental survey].

The occupational exposure to nitrous oxide and other anaesthetic agents in two hospitals was measured with personal samplers. The highest concentration of nitrous oxide was found in the orthopaedic theatre (2932 ppm), but in other operating theatres the values were not less than 200 ppm. Both the average volume of anaesthetic gases and vapours used per patient and per room and lack of appreciable active ventilation may affect the exposure of staff, potentially at risk from excessive occupational exposure to anaesthetic agents. These observations suggest that adequate health and safety programmes should be established in occupational health care.

Air Pollutants, Occupational↗
PubMedDate not supplied

Usefulness and safety of pirenzepine in double-contrast study of upper gastrointestinal tract: comparison with scopolamine methylbromide.

To evaluate usefulness of pirenzepine, a selective M1 antimuscarinic drug, for diagnostic double-contrast study of the upper gastrointestinal tract, pirenzepine and scopolamine methylbromide (SMB) were compared in a single blind randomized trial. Seventy consecutive patients were enrolled in the study. Artifacts, bowel distention, painting of stomach and duodenal bulb, and global quality of the images were blindly evaluated by four independent observers by means of a numerical score (1-4). Under SMB slightly but significantly better results for stomach were scored (3.1 +/- .7 vs. 2.7 +/- 7, p < 0.01). No differences were found in the study of the duodenal bulb. Heart rate and rhythm during the study were recorded by electrocardiogram (ECG). SMB induced tachycardia in all patients (from 77 +/- 20 to 117 +/- 28 beats/min, p < 0.01) while pirenzepine did not (from 77 +/- 16 to 81 +/- 23, p = NS). After SMB, two patients exhibited faintness, and some patients complained of visual accommodation defects, dryness of the mouth, and dizziness. Thus, pirenzepine provides good results in double-contrast studies (equal to SMB), while presenting no adverse effects. It could be proposed as a first choice hypotonic agent in upper gastrointestinal examination.

Adult↗
PubMedDate not supplied

Pirenzepine versus scopolamine methyl bromide in double-contrast barium enema study of large bowel.

To evaluate the usefulness of pirenzepine for diagnostic double-contrast barium enema study of the large bowel, pirenzepine and scopolamine methyl bromide (SMB) were compared in a single, blind, randomized trial. Sixty consecutive patients were enrolled in the study. Quantitative analysis of bowel distention was done by measuring the maximum diameter of the transverse colon before and after drug administration. Four independent observers blindly evaluated distention and mucosal coating of the large bowel and global quality of the images. No differences were found in the diagnostic performance between the two drugs. However, pirenzepine induced a slight but significantly larger distention of the large bowel (68 +/- 12 vs. 65 +/- 8 mm, p = 0.02). Heart rate and rhythm during the study were recorded by ECG. SMB induced tachycardia in all patients (from 72 +/- 15 to 98 +/- 24 beats/min, p < 0.01), whereas pirenzepine did not (from 76 +/- 13 to 78 +/- 20, p = NS). After SMB, one-patient exhibited faintness, and some patients complained of visual accommodation defects, dryness of the mouth, and dizziness. Pirenzepine had a diagnostic performance similar to SMB in avoiding adverse effects elicited by SMB.

Adult↗
PubMedDate not supplied

Relationship between age and GSH metabolism in synaptosomes of rat cerebral cortex.

A comprehensive analysis on glutathione metabolism in rat cerebral cortex synaptosomes as a function of age was performed. All different glutathione system components (GSH, GSSG, total GSH, and GSH redox index) changed significantly only during aging. GSH, total GSH, and GSH redox index decreased by about 40%, 24%, and 52%, respectively, while GSSG showed a remarkable increase of about 60%. On the contrary, some GSH-related enzyme activities showed characteristic changes both during growth and aging. GSH peroxidase and GSH-S-transferase activities significantly increased both during growth and aging, GSH reductase and gamma-glutamylcysteine synthetase activities showed lower levels only during aging, while glucose-6-phosphate dehydrogenase activity did not change throughout the life of the rat. The results obtained suggest an increase of the oxidative status due to a reduced antioxidant capacity of the GSH system in the synaptosomal compartment during aging. The main cause of these metabolic modifications is a lowering of the rates of both GSSG reduction to GSH and GSH synthesis. Moreover, an irreversible loss of GSH as GSH-S-conjugates due to a high detoxification mechanism during aging is also possible. These alterations in glutathione metabolism, found mainly during aging in rat cerebral cortex synaptosomes may contribute to clarify some aspects of cerebral diseases.

Aging↗
PubMedDate not supplied

Glutathione metabolism in heart and liver of the aging rat.

A comprehensive study on glutathione metabolism in rat heart and liver as a function of age was performed. In the heart, reduced glutathione, total glutathione, and the glutathione redox index showed a decrease during aging, while oxidized glutathione levels increased in 5-month-old rats with respect to the young animals and remained quite constant in 14- and 27-month-old rats. In the liver, the highest levels of reduced glutathione were found in the 2-month-old rats, while oxidized glutathione reached a peak at 5 months. Glutathione-associated enzymes showed age-related changes. Glutathione peroxidase, unaffected by aging in the heart, decreased in the liver of the 27-month-old rats. In the heart and the liver, the highest values of glutathione S-transferase were found at 5 months and 27 months, respectively. Glucose-6-phosphate dehydrogenase followed a similar trend in both heart and liver. Glutathione reductase also showed the same behaviour in heart and in liver, increasing in old rats with respect to the other age groups. A decrease in gamma-glutamylcysteine synthetase was found in the heart and liver of 27-month-old rats in comparison with the 2-month-old ones. In conclusion, a decreased antioxidant capability has been demonstrated in both heart and liver of old rats.

Aging↗
PubMedDate not supplied

[Occupational respiratory allergopathies: environmental monitoring, air allergens, prevention].

The prevalence of allergic diseases has increased over recent years. Several epidemiological studies have been undertaken to determine the prevalence and the incidence of asthma and/or rhinitis caused by occupational allergens, and to investigate the factors that may affect their occurrence. In the last decade, with the development of methods to measure airborne allergens concentrations. Studies have been undertaken to examine the relationship between the levels of airborne allergens and the development of symptoms. In this paper we have reviewed the main studies published on the topic, and focused our attention on three aeroallergens (wheat flour proteins, latex and laboratory animal allergens), that have been thoroughly investigated in literature, from both clinical, epidemiological and laboratory aspects, which highlighted the major responsible allergens and tried to set up the dose-response relationship for symptoms and for sensitization. These studies cannot be directly compared to each other because of differences in the methods; however they seem to suggest that low levels of airborne allergens may be sufficient to sensitize individuals. In contrast, the evidence for a dose-response relationship between exposure and symptoms is indirect and not always clear. Further epidemiological studies are necessary. In occupational medicine the presence of asthma or of another allergic disease in a severe form is suggested as a criterion for excluding workers from their job. Workers that do not manifest allergic symptoms but are atopic should be informed about the risk of developing occupational respiratory diseases, and periodic check-ups are strongly recommended. Medical controls must not be disconnected from environmental controls. Standardized methods of measurement of airborne allergens for environmental control need to be set in order to allow comparison between studies and to adopt primary prevention measures.

Air Pollutants, Occupational↗
PubMedDate not supplied

Early production of HIV-1 neutralising antibodies in patients following highly active antiretroviral treatment (HAART) during primary HIV infection.

We investigate the effects of highly active antiretroviral therapy (HAART) on humoral immune responses during a 24-month follow up of 15 HIV patients with acute primary HIV infection. The patients were divided into three groups on the basis of the therapeutic protocol they were following at the time of entry: a) five naive patients (untreated or treated with only ZDV or AZT); b) five patients following a triple combination of ZDV+ lamivudine (3TC)+ saquinovir (SQV); and c) five patients on a four-drug combination of ZDV+3TC+SQV+ ritonavir (RTV). The results show that the early introduction of HAART greatly reduces plasma viremia levels and restores the number of CD4 cells. A significant correlation was found between anti HIV neutralising activity and the four-drug, but not the three-drug combination. The reduction in infectivity was directed against viruses of different clades and associated with immunoglobulin fractions. Moreover, the neutralising antibodies in the HAART-treated patients appeared after two weeks of treatment and remained stable throughout the 24 months of follow up. The early appearance of neutralising antibodies represent an important component of immune responses during primary HIV infection, may contribute towards immune reconstitution in patients on HAART, and give further information that may be useful in developing new strategies designed to eradicate the disease.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

[Evaluation and quantification of biologic risk in the hospital setting with ATP determination on work surfaces].

The purpose of this study was to establish whether a method of determining ATP levels using the HY-Lite system could be reliably applied in the various hospital workplaces. We estimated the correlation between ATP levels and the number of C.F.U. (Colony Forming Units), observed correlation r = 0.96. We established hygienically acceptable values for each environment, and drew up reference tables. The study reveals that conditions of high bacterial and fungine contamination can occur, albeit the agents are not normally pathogenic is so far as they consist of common environmental pollutants. Consequently, these results emphasize the need to apply strict sanitization and hygienic measures, that health workers must be suitably trained to deal with follow. The results of the sampling appear to suggest that condition of potential biological risk for workers are largely due to incorrect work procedure in workplaces where pathologic agents are present.

Adenosine Triphosphate↗
PubMedDate not supplied

[Measurement of N-methylformamide in occupational exposure to N,N-dimethylformamide].

N,N-dimethylformamide (DMF) is a solvent that is widely used in industry. The major occupational sources of exposure results from production of synthetic leather. The main metabolite formed in both man and animals is N-hydroxymethyl-N-methylformamide. Demethylation leads to N-methylformamide (NMF) and formamide and also to a small extent to hydroxy-methylformamide. All the metabolites are excreted in urine, as are very small amounts of the unchanged substance. N-acetyl-S-(N-methyl-carbamoyl)-cysteine can be determined in urine as a further metabolite. We conducted this biomonitoring study with the aim of evaluating the correlation between the excretion of N-methylformamide (mainly from N-hydroxymethylformamide) and levels of exposure to N,N-dimethylformamide among occupationally exposed people. The mean time-weighted average (TWA) exposure was about half (13.5 mg/m3) of the current threshold limit value, the range of the values varying from 0.4 to 75.2 mg/m3. A linear equation existed between urinary NMF concentration and DMF concentration in the environment. The findings show that the urinary NMF concentration can be used as an appropriate biological exposure index. The authors suggest for occupationally exposed subjects, a urinary NMF concentration corresponding to the time-weighted average of the threshold limit value of 39.9 mg/l (37.2 mg/g creatinine) and a 95% lower confidence limit (biological threshold) of 23.4 mg/l (22.2 mg/g creatinine).

Adult↗