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Biomedical subjects

G Aru

Publications and source records attributed to G Aru.

At least 19 recordsLinked to original sources
PubMed2001

Mortality from lung cancer among silicotic patients in Sardinia: an update study with 10 more years of follow up.

OBJECTIVES: To evaluate the association between silica, silicosis and lung cancer, the mortality of 724 patients with silicosis, first diagnosed by standard chest x ray film between 1964 and 1970, has been analysed by a cohort study extended to 31 December 1997. METHODS: Smoking and detailed occupational histories were available for each member of the cohort as well as the estimated lifetime exposure to respirable silica dust and radon daughters. Two independent readers blindly classified standard radiographs according to the 12 point International Labour Organisation (ILO) scale. Lung function tests meeting the American Thoracic Society's criteria were available for 665 patients. Standardised mortality ratios (SMRs) for selected causes of death were based on the age specific Sardinian regional death rates. RESULTS: The mortality for all causes was significantly higher than expected (SMR 1.35, 95% confidence interval (95% CI) 1.24 to 1.46) mainly due to tuberculosis (SMR 22.0) and to non-malignant chronic respiratory diseases (NMCRD) (SMR 6.03). All cancer deaths were within the expected numbers (SMR 0.93; 95% CI 0.76 to 1.14). The SMR for lung cancer was 1.37 (95% CI 0.98 to 1.91, 34 observed), increasing to 1.65 (95% CI 0.98 to 2.77) allowing for 20 years of latency since the first diagnosis of silicosis. Although mortality from NMCRD was strongly associated to the severity of radiological silicosis and to the extent of the cumulative exposure to silica, SMR for lung cancer was weakly related to the ILO categories and to the cumulative exposure to silica dust only after 20 years of lag interval. A significant excess of deaths from lung cancer (SMR 2.35) was found among silicotic patients previously employed in underground metal mines characterised by a relatively high airborne concentration of radon daughters and among ever smokers who showed an airflow obstruction at the time of the first diagnosis of silicosis (SMR 3.29). Mortality for lung cancer related to exposure was evaluated with both the Cox's proportional hazards modelling within the entire cohort and a nested case-control study (34 cases of lung cancer and 136 matched controls). Both multivariate analyses did not show any significant association with cumulative exposure to silica or severity of silicosis, but confirmed the association between mortality for lung cancer and relatively high exposure to radon, smoking, and airflow obstruction as significant covariates. CONCLUSIONS: The findings indicate that the slightly increased mortality for lung cancer in this cohort of silicotic patients was significantly associated with other risk factors-such as cigarette smoking, airflow obstruction, and estimated exposure to radon daughters in underground mines-rather than to the severity of radiological silicosis or to the cumulative exposure to crystalline silica dust itself.

Adult↗
PubMed2000

Nutritional factors and worldwide incidence of childhood type 1 diabetes.

BACKGROUND: Some dietary factors have been associated with the risk of type 1 diabetes in childhood. OBJECTIVE: We investigated relations between dietary energy from major food groups and incidence of childhood type 1 diabetes by using an ecologic study design. DESIGN: We conducted univariate and multivariate regression analysis with incidence rates of type 1 diabetes in the late 1980s and early 1990s among children aged <15 y in 40 countries as the dependent variable and average per capita daily intake of major food items and other socioeconomic, demographic, and geographic risk factors as the independent variables. RESULTS: In the univariate regression model, per capita total energy intake was nonsignificantly associated with type 1 diabetes incidence (r = 0.31, NS), whereas energy from animal sources was associated (r = 0.61, P < 0.01) and energy from vegetal sources was inversely associated (r = -0.35, P < 0.05) with diabetes incidence. Among dietary items of animal origin, meat (r = 0.55, P < 0.001) and dairy products (r = 0. 80, P < 0.0001) were predictors of elevated incidence rates, whereas among dietary items of vegetal origin, cereals (r = -0.64, P < 0. 001) were inverse predictors. In the multivariate analysis, the inverse relation of diabetes incidence with energy from vegetables and the direct correlation with energy from animal sources explained the positive associations of type 1 diabetes incidence with geographic and socioeconomic covariates. CONCLUSION: The incidence of type 1 diabetes varied worldwide according to dietary patterns. In-depth exploration of dietary risk factors during pregnancy and early neonatal life is warranted to confirm whether and to what extent diet cooperates with genetic susceptibility in the early onset of type 1 diabetes.

Adolescent↗
PubMed1996

Dust exposure, respiratory symptoms, and longitudinal decline of lung function in young coal miners.

OBJECTIVES: To study the role of dust exposure on incidence of respiratory symptoms and decline of lung function in young coal miners. METHODS: The loss of lung function (forced vital capacity (FVC), forced expiratory volume in one second (FEV1), forced expiratory flow (MEF), carbon monoxide transfer factor (TLCO)) with time and the incidence of respiratory symptoms in 909 Sardinian coal miners (followed up between 1983 and 1993 with seven separate surveys) has been compared with the past and current individual exposures to respirable mixed coal dust. Multiple linear and logistic regression models were used simultaneously controlling for age, smoking, past occupational exposures, and other relevant covariates. RESULTS: According to the relatively low dust exposures experienced during the follow up few abnormal chest x ray films were detected. In the cross sectional analysis of initial data, significant associations between individual cumulative exposure to dust, decrements in FEV1 and MEFs, and increasing prevalence of respiratory symptoms were detected after allowing for the covariates included in the model. The yearly decline of FVC, FEV1, and single breath carbon monoxide transfer factor (TLCO/VA) was still significantly related to the individual exposure to dust experienced during the follow up, even after allowing for age, smoking, initial cumulative exposure to dust, and initial level of each functional variable. In logistic models, dust exposure was a significant predictor of the onset of respiratory symptoms besides age and smoking. CONCLUSIONS: The results show that even moderate exposures to mixed coal dust, as in our study, significantly affect lung function and incidence of symptoms of underground miners. Although the frequency of chest x ray examination might be fixed at every three or four years, yearly measurements of lung function (spirometry, MEFs, and TLCO) are recommended for evaluation of the respiratory risk from the coal mine environment to assess the need for further preventive interventions.

Age Factors↗
PubMed1986

The use of intraluminal prosthesis in the surgical management of aortic dissection.

The treatment of acute aortic dissection requires expeditions and reproducible operations aimed at avoiding rupture of the dissection or its antegrade or retrograde progression. In 12 type A and 11 type B dissections the aorta was repaired using an intraluminal prosthesis to reduce the risk of hemorrhage and its related complications. Overall mortality rates were 33% in type A and 36% in type B patients, similar to that observed in patients operated with other techniques, but the incidence of intraoperative bleeding was possibly reduced and the cross-clamping time was significantly shorter. This method of repair is a sound alternative to conventional anastomotic suturing, particularly in clinically compromised patients and in the hands of surgeons on call, who may lack the experience of dealing with a particularly fragile aortic wall.

Aged↗
PubMed1984

Dehiscence of aortic valve prostheses: analysis of a ten-year experience.

Up to the end of 1982, reoperation for dehiscence of an aortic prosthesis was necessary in 5% of patients operated on for primary aortic valve replacement in the previous decade at the University of Padova Cardiac Surgery Center. This complication occurred early (median time to diagnosis 4 months) and was associated with an elevated 30-day operative mortality (27%, 70% CL 19-37%). This is probably (P = 0.09) related to preoperative heart failure. The follow-up of the traced surviving patients (92%) indicates a continuing poor prognosis with a 6-year survival rate of only 13.5% (70% CL 5.0-30%). All the events were cardiac related and directly or indirectly connected with the persistence or recurrence of dehiscence that was observed in 72% of the cases. In the face of these results, a retrospective study has been performed to identify, on the basis of the available data, the subsets of patients more prone to develop this complication. Our results suggest that a significant increased risk (P less than 0.001) can be identified in patients presenting with bacterial endocarditis (12.2% rate), in patients with concomitant aneurysm of the ascending aorta (10.9%) and in patients with degenerative regurgitation or severe calcifications of their native valve, with rates of 7.0 and 6.0 respectively. In these situations particular care is required to avoid undue stress on the annular tissue. We also suggest the use of buttressed interrupted sutures.

Adult↗
PubMed1983

Mitral valve prosthesis dehiscence necessitating reoperation. An analysis of the risk factors involved.

Between January 1970 and December 1981, a total of 21 reoperations for periprosthetic leak were performed on 20 patients out of 999 with previously implanted prosthetic mitral valves. In most of them reoperations were performed within the first year, since the initial procedure and the leading indications were intractable congestive heart failure or infection of the mitral prosthesis. The mortality rate was 30% and was related to the preoperative cardiac functional status. The preoperative variables significantly related to an increased incidence of dehiscence of the mitral prosthesis necessitating reoperation were a degenerative disease (P = 0.016) or an infective endocarditis (P = 0.0006) of the native valve, both causing mitral regurgitation. Rheumatic disease, type of prosthesis, supra- or subannular insertion, age of the patient, and operative year, were not significant, neither were calcifications that are probably neutralized by the routine use of special surgical techniques. It is suggested that the use of techniques specifically designed to eliminate periprosthetic leak in patients affected by mitral regurgitation due to degenerative or infective disease of the native valve, might lead to a further reduction of reoperations for this complication.

Adolescent↗
PubMed1983

Acute mitral regurgitation after blunt chest trauma.

We treated a case of isolated acute mitral incompetence due to complete transection of the anterior papillary muscle produced by blunt chest trauma. The excellent results obtained with conservative therapy suggest that this approach be used in other similar cases. The pertinent medical literature is reviewed.

Adolescent↗
PubMedDate not supplied

Regurgitant flow of mitral valve prostheses: an intraoperative transesophageal echocardiographic study.

To assess the regurgitant characteristics of mitral biologic and mechanical prostheses immediately after implantation, intraoperative transesophageal echocardiography was performed in 27 patients, aged 32 to 69 years, undergoing open-heart surgery for rheumatic heart disease (n = 19), mitral valve prolapse (n = 3), malfunctioning prostheses (n = 3), or periprosthetic leaks (n = 2). The prostheses included 13 biologic (Carpentier-Edwards) and 14 mechanical valves (five Starr-Edwards, five Medtronic-Hall, and four Bjork-Shiley). Physiologic transvalvular regurgitant flow was detected in both biologic and mechanical prostheses. The spatial extent of the regurgitant jets was usually greater in the mechanical than in the biologic valves, and systolic jets, characteristic of each type of valve, were visualized consistently. Trivial periprosthetic jets (PPJs) were observed in many implanted valves (14/27). The median maximal jet area was 0.46 cm2 (range 0.1 to 1.5 cm2). Cardiopulmonary bypass was reinstituted in two patients. In one patient a PPJ was judged extensive enough (area 3.6 cm2) to warrant surgical revision of the implant, but no dehiscence was found. In the other patient a turbulent PPJ (area 5.5 cm2) was associated with a 0.5 cm dehiscence at the surgical inspection. In conclusion, (1) all mitral prostheses exhibit physiologic transvalvular regurgitation, (2) trivial mitral PPJ is a common finding in newly implanted mitral valves and does not require the revision of the implant, and (3) further experience based on larger series of patients is required to determine the maximal acceptable size of a mitral PPJ detected by intraoperative transesophageal echocardiography.

Bioprosthesis↗
PubMedDate not supplied

[Incremental stress test: comparison between protocols and cardiorespiratory reference values in healthy workers].

The aim of this study was double: to compare two different incremental stress protocols and to obtain reference values for a standardised exercise test in healthy workers. Firstly, eighty healthy male workers, 40 coal miners and 40 hospital workers, aged 19-54, performed in 2 different days 2 cycle ergometer tests up to exhaustion, increasing the work load respectively by 30 watts every 3 minutes (protocol A) and by 30 watts each minute (protocol B). Ventilatory and gas exchange measurements were done by a breath-by-breath apparatus equipped with a turbine and fast gas analysers for O2 and CO2. For each test the ventilatory anaerobic threshold (VAT) was blindly determined as oxygen uptake (V'O2 VAT) using standardised gas exchange and ventilatory indices (V'CO2, V'E, V'E/V'O2) that were found giving comparable results with those derived from the blood lactacte curve. Significant differences were observed between the two protocols only concerning the average work load at exhaustion and at the VAT: the highest being with the protocol B. Conversely, either the maximal oxygen uptake (V'O2 max) and the V'O2 VAT were comparable between protocols, as well as the other cardio-respiratory parameters were at these exercise levels. Oxygen uptake and heart rate increased in average linearly with the work load with very similar slopes in both protocols. Comparable results between protocols were found also as what concerns the slopes of the other physiological variables (V'E, V'CO2) analysed against the V'O2, particularly for exercise levels lower or equal to the individual VAT. Thus, these results suggest a very good comparability between the two protocols, concerning both the levels of maximal and sub-maximal aerobic capacity (V'O2 max, V'O2 VAT) and the cardio-respiratory pattern related to the oxygen uptake. Reference values for the 30 watts/3 minutes cycle ergometer stress test were achieved in other 320 healthy Sardinian workers concerning both the maximal (V'O2 max) and sub-maximal (V'O2 VAT) aerobic capacity and the range of normality for the cardio-respiratory pattern during the test, particularly for completely aerobic work loads, namely work loads not above the V'O2 VAT. These prediction equations can be useful for the evaluation of working capacity of workers employed in manual jobs characterised by moderate-to-high dynamic energy expenditure.

Adult↗