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A novel fiber optic sensing technology for high frequency dynamics detection is proposed in this paper, specifically tailored for structural health monitoring applications based on strain wave analysis, for both passive impact identification and active Lamb wave monitoring. The sensing solution relies on a fiber optic-based interferometric architecture associated to an innovative coherent detection scheme, which retrieves in a completely passive way the high-frequency phase information of the received optical signal. The sensing fiber can be arranged into different layouts, depending on the requirement of the specific application, in order to enhance the sensor sensitivity while still ensuring a limited gauge length if punctual measures are required. For active Lamb wave monitoring, this results in a sensing fiber arranged in multiple loops glued on an aluminum thin panel in order to increase the phase signal only in correspondence to the sensing points of interest. Instead, for passive impact identification, the required sensitivity is guaranteed by simply exploiting a longer gauge length glued to the structure. The fiber optic coherent (FOC) sensor is exploited to detect the strain waves emitted by a piezoelectric transducer placed on the aluminum panel or generated by an impulse hammer, respectively. The FOC sensor measurements have been compared with both a numerical model based on Finite Elements and traditional piezoelectric sensors, confirming a good agreement between experimental and simulated results for both active and passive impact monitoring scenarios., Competing Interests: The authors declare no conflict of interest.

Objective: The main purpose of this study was to compare efficacy, tolerability and influence on quality of life (QOL) of nifedipine gastrointestinal therapeutic system (NI) 30-60 mg once a day vs amlodipine (AM) 5-10 mg once a day in elderly patients with mild-moderate hypertension., Design: This was a randomized, double-blind, parallel-group, multicenter study. After a 2-week single-blind placebo run-in, patients were randomized to either NI 30 mg or AM 5 mg. Responders continued on the same dosage for 16 additional weeks, while non-responders were titrated to 60 mg NI or 10 mg AM., Methods: Blood pressure was measured by mercury sphygmomanometer and efficacy equivalence of NI and AM tested by covariance analysis. Diastolic blood pressure (DBP) was the primary efficacy parameter, its baseline value being taken as covariate while centers effect and treatment interaction were included as fixed effects in the analysis model. The secondary efficacy variables systolic blood pressure (SBP) and scores for QOL were analyzed according to the same model., Results: At the end of the study, overall mean DBPs, calculated as least-square means (LSMEANS), in the "by protocol" population were 87.5 mmHg for NI and 86.7 for AM (difference 0.8 mmHg with 90% CI -1.2 to 2.8 mmHg). In the "by intention to treat" (ITT) population LSMEANS were 87.6 mmHg for NI and 86.4 mmHg for AM (difference 1.2 mmHg with 90% CI -0.6 to 3.1 mmHg). SBP LSMEANS in the "by protocol" population were 147.7 mmHg for NI and 147.3 mmHg for AM (difference 0.3 mmHg, with 90% CI -3.7 to 4.3); corresponding values in the "by ITT" population were 148.0 mmHg for NI and 147.2 for AM (difference 0.8 mmHg, with 90% CI -2.8 to 4.6). Mean values for QOL parameters were not significantly different. A total of 173 episodes of adverse events were documented in 54 patients (26 NI and 28 AM), dropouts were 15 (20% of group) on NI and 21 (28%) on AM., Conclusions: NI 30-60 mg was shown to be as efficacious and safe as AM 5-10 mg in elderly patients with mild-moderate hypertension. QOL improved compared to baseline with no significant difference between the two drugs, thus confirming a positive class effect for calcium antagonists.

According to recent international guidelines the decision on whether to treat young subjects during the early phase of hypertension should be based not only on their office blood pressure but also on their ambulatory blood pressure and whether target organ damage has occurred. Few data on the prevalence of hypertensive complications in young subjects with mild hypertension are available. In the Hypertension and Ambulatory Recording Venetia Study (HARVEST), a multicenter trial conducted in northeast Italy, the percentage of young borderline-to-mild hypertensive subjects with echocardiographic left ventricular hypertrophy was 4.5% and the percentage with concentric remodeling was 4%. Clear differences in cardiac size and geometric adjustment to ambulatory systolic pressure between the two sexes were found. The impact of blood pressure on the walls of the left ventricle and on the left ventricular mass was remarkable in women but weak in men. The assessment of left ventricular systolic function confirmed that many young mild hypertensive subjects have an increased ejective performance. The left ventricular contractility evaluated by midwall measurement was, however, found to be depressed in 9.2% of the HARVEST participants. Their left ventricular diastolic function was similar to that of 50 normotensive controls. The prevalence of microalbuminuria [albumin excretion rate (AER) > 30 mg/24 h) was 6.1%, only slightly higher than that found by other authors among normotensive subjects and much lower than that observed among patients with more severe hypertension. For our stage I hypertensives, however, the AER was correlated to the 24 h blood pressure with high statistical significance, whereas we found no relationship between the AER and left ventricular mass index either for all of the subjects taken together or for the men and women considered separately. The results suggest that renal and cardiac involvement do not occur in parallel during the initial phase of hypertension.

The objective of the present study was to examine the association between albumin excretion rate (AER) and office and ambulatory blood pressures (BP), and other recognized cardiovascular risk factors in stage I hypertension. The study was carried out in 870 never-treated 18- to 45-year-old hypertensives (628 men, 242 women). Office and ambulatory BP, 24-h urinary collection for AER assessment, and echocardiographic left ventricular mass (n = 587) were obtained. AER was similar in men and women (12.3 v 12.5 mg/24 h) and was unrelated to age and body mass index. In 85.2% of the subjects, AER was < 16 mg/24 h, in 8.3% it was between 16 and 29 mg/24 h (borderline microalbuminuria), and in 6.1% it was >or= 30 mg/24 h (overt microalbuminuria). Office systolic BP was not different in the three groups, whereas 24-h systolic BP was higher in the subjects with microalbuminuria than in those with normal AER (P < .0001) and was similar in the two microalbuminuric groups. Office and 24-h diastolic BPs were higher in the subjects with overt microalbuminuria than in those with normal AER. Left ventricular mass was correlated to systolic (P < .0001) and diastolic (P = .01) 24-h BP, but was unrelated to AER. Family history for hypertension, smoking, coffee and alcohol intake, and physical activity habits did not influence AER. In a logistic regression analysis, 24-h systolic BP emerged as the only determinant of microalbuminuria (P < .0001). In conclusion, these results indicate that borderline levels of microalbuminuria may also be clinically relevant in stage I hypertension. Overweight and lifestyle factors do not appear to influence AER in these patients. Finally, the lack of correlation between AER and left ventricular mass suggests that renal and cardiac involvement do not occur in a parallel fashion in the initial phase of hypertension.

A 34-year man was admitted to the hospital with symptoms of hypoglycemia. The endocrine investigations indicated adrenocortical insufficiency secondary to isolated ACTH deficiency: low ACTH and cortisol plasma levels, significant increase of cortisol following prolonged stimulation with depot tetracosactrin, normal secretory reserve of other anterior pituitary hormones. The absence of ACTH-response after corticotropin releasing hormone and insulin tolerance tests suggested a primary impairment of corticotropin cells.

AGAPE (Computer-based Outpatients' Clinic Programme) is a programme for IBM-compatible microcomputers realised by physicians for the management of hypertensive patients. The programme is planned to make the operators' work complete and expeditious while, at the same time, respecting the standard formulation of the clinical approach to the patient. The collection, organisation, recording and communication of data are handled on line by the programme under the operator's control. Special attention has been given to the control of the quality of the data collected as well as to their easy use for clinical, research and statistical purposes. This programme was used for 52 months in a hypertension clinic where physicians and nurses work jointly. Up to April 1989, 1924 new patient visits and 10,639 control visits together with 3,375 groups of lab tests were inserted. The mean training time for new operators was 3.2 hours; the mean data insertion time was 12.5 minutes for the first visit, 3 minutes for the subsequent visits and 2.5 minutes for lab tests. The drop-outs, evaluated at one-year follow-up on each 250 patients before and after the introduction of the computerized system, were 84/250 and 64/250 respectively (p less than 0.05), with a trend to wards the better control of hypertension (diastolic blood pressure less than 90 mmHg, 128/250 vs 143/250, n.s.).

The aim of the present study was to evaluate changes in urinary micro-albumin and in serum and urinary beta 2-microglobulin during treatment with captopril at low doses in a group of hypertensive outpatients without any sign of renal impairment. Thirty-four patients with essential hypertension entered the study, all having been treated for at least one year with beta-blockers and diuretics. None had proteinuria (by Albustix) and creatinine clearance was normal. The patients were randomly allocated to two groups: the first group was maintained on the previous regimen (group BD) and the second received captopril 50 mg twice daily instead of the beta-blocker (group CD). During the year of observation blood pressure values and serum and urinary beta 2-microglobulin were not significantly different between the two groups. There was, however, a significant reduction in albumin excretion rate (AER) in the CD group at both 3 and 6 months. Since arterial measures did not differ between the two groups, it is proposed that the reduction of AER was due to a diminution of the transcapillary hydraulic pressure due to the inhibition of the intrarenal angiotensin II induced by captopril.

Among the various syndromes caused by excess mineralocorticoids, the factitious syndrome produced by excessive 9-alpha-fluorprednisolone inhalations is more common than might be expected, especially in places where the drug is easily obtained without a doctor's prescription. A fairly typical case of addiction to a nasal spray containing ephedrine hydrochloride and an imidazoline compound as well as the steroid is described. The diagnosis of the case is analysed with details of certain differences from similar cases reported in the literature and the modifications to clinical and instrumental parameters achieved after over two months' treatment with spironolactone are described.

Prolactin (PRL) and thyrotropin (TSH) serum levels were determined in a group of young female heroin addicts treated in hospital with methadone in tapered doses. At admission, from 24 to 3 h after the last dose of 'street' heroin, basal PRL values were 21 +/- 2.6 ng/ml, i.e. significantly higher (P less than 0.001) than in controls: 9.8 +/- 0.7; there was no significant differences of basal TSH values between heroin addicts and normal subjects: 2.5 +/- 0.2 vs. 2.2 +/- 0.1 mu units/ml, respectively. The day after admission, when methadone treatment was begun, the PRL and TSH pituitary response to thyrotropin releasing hormone (TRH) 200 micrograms i.v. in 12 patients was studied. The PRL response was significantly reduced (P less than 0.001) in heroin addicts vs. controls, the mean values of highest percent increments over basal were 368 +/- 41.8 and 847 +/- 80.7, respectively. The TSH response in the two groups was similar, the mean highest per cent increment over basal 393 +/- 53.4 in heroin addicts vs. 367 +/- 39.2 in controls. The increase of the PRL basal concentration and its decreased pituitary response following TRH were probably related to a change in the tuberoinfundibolar dopaminergic system (TIDA) because of a chronic intake of opiates whereas the impaired function of the dopaminergic system did not alter the thyrotropin pituitary secretion.