Vascular signals arising from pleura-based lung lesions were studied in 50 patients using pulsed Doppler ultrasonography. Twenty-seven had malignant lesions and 23 benign lesions. In 24/27 of the malignant masses, we observed no Doppler signals: in 2 cases, a low-velocity, turbulent, pulsatile flow was demonstrated; in 1 case pulsed Doppler ultrasonography showed only a low-velocity, continuous flow. In 20/23 of the benign lesions, we found 2 types of Doppler signal waveforms: an irregularly pulsatile, venous-like signal, and a regularly pulsatile, arterial-like waveform. The last 8 patients of our series underwent color Doppler ultrasound examination, which demonstrated the presence of arterial and venous vessels in 4 benign lesions and the absence of blood flow in 4 malignant masses. To our knowledge, we report for the first time the ability of obtaining Doppler signals from a variety of lung lesions. The actual clinical relevance of this application requires further studies.

Adult↗

PubMedDate not supplied

Management of hypertension by general practitioners: an Italian observational study.

Data on patients receiving antihypertensive therapy were collected from 20 general practitioners (GPs) in Campania, Italy, to determine the prescription of different antihypertensive classes and their use with other drugs for concomitant diseases, to investigate the main factors influencing antihypertensive choice, to document treatment outcome, and to assess adverse drug reactions (ADRs). Each GP completed a data card for each consultation that produced an antihypertensive prescription; 1900 cards were collected. The most frequently used antihypertensives were angiotensin-converting enzyme inhibitors (49.6%), calcium antagonists (24.8%), beta blockers (11.7%), angiotensin II-receptor blockers (5.5%), and alpha blockers (0.9%). In 82% of patients, blood pressure was reduced but did not reach normotensive levels. The choice of antihypertensive treatment was influenced by international guidelines (56%), clinical diagnosis (25%), concomitant diseases (8%), cost (4%), compliance (3%), and other factors (5%). ADRs--most often cough (35.7%), edema (22.7%), headache (13.3%), and tachycardia (7.8%)--occurred in 11.8% of patients.

Antihypertensive Agents↗

PubMedDate not supplied

Self-prescribed laxative use: a drug-utilization review.

This study was conducted to determine the reasons for the choice of self-prescribed laxatives and to acquire information on how they were used and tolerated. From November 1999 to February 2000, 70 pharmacies, uniformly located throughout the Campania region of southern Italy, distributed a questionnaire to purchasers of over-the-counter laxatives. The average age of the (mostly female) respondents was 45.9 years; 23.8% were elderly. Among the 7324 individuals who completed the survey, 77.6% selected an oral product; 22.4% preferred rectal administration. A physician influenced the choice of a laxative in 37.7% of the cases, a pharmacist in 20.5%; other suggestions came from relatives (14%), acquaintances (12.1%), advertisements (11.7%), and miscellaneous sources (4%). Only 59.8% of respondents used these drugs correctly, and 58.2% consulted a physician or pharmacist because of constipation. Adverse effects, mainly gastrointestinal symptoms, occurred in 6.1% of those surveyed. The long-term use or abuse of laxatives can cause serious medical consequences, as well as mask diseases, delaying diagnosis and appropriate treatment. Physicians, pharmacists, and other health-care personnel should counsel patients on the proper use of these easily available, ubiquitous drugs.

Adolescent↗

PubMedDate not supplied

Inhibition of L-carnitine uptake into primary rat cortical cell cultures by GABA and GABA uptake blockers.

L-carnitine plays a central role in mitochondrial function and is found to be differentially distributed in the brain. We have shown before that the uptake of L-carnitine into cultured rat cortical neurones was temperature-dependent, as well as potently inhibited by factors affecting the sodium gradient as well as by molecules resembling its structure, e.g. D-carnitine, acetyl-L-carnitine and gamma-aminobutyric acid (GABA). GABA was the most potent inhibitor of L-carnitine uptake. In the present study we have found that specific GABA uptake blockers, nipecotic acid, cis-4-hydroxynipecotic (HNA), guvacine, 2,4-diaminobutyric acid (DABA) and NO 711 inhibit L-carnitine uptake even more potently than GABA. However, apart from NO 711, they caused about the same maximal inhibition, 67.4% at 50 microM for guvacine, compared to 60.5% by GABA. NO 711 was extremely potent and blocked 80.5% of the L-carnitine uptake. In contrast, the GABAA receptor agonists, isonipecotic acid and isoguvacine, or the antagonist bicuculline, at similar concentrations (50 microM), did not significantly inhibit the uptake of the L-carnitine. However, bicuculline at relatively high concentration (500 microM) was inhibitory (38%). The GABAB receptor agonist, baclofen, or antagonist, phaclofen, were ineffective, although 5-aminovaleric acid did significantly inhibit uptake at both 50 and 500 microM, causing 22 and 48% inhibition respectively. Like bicuculline, it was not as effective as GABA or the specific GABA uptake blockers. The results indicate that the uptake of L-carnitine by rat cortical neurones occurs in part by a process that can be potently inhibited by GABA and GABA uptake blockers.

Animals↗

PubMedDate not supplied

Increase in beta-galactosidase activity in a non-isothermal bioreactor utilizing immobilized cells of Kluyveromyces fragilis: fundamentals and applications.

The beta-galactosidase activity of Kluyveromyces fragilis cells immobilized in a kappa carrageenan gel was studied in a bioreactor functioning under isothermal and non-isothermal conditions. We observed an increase in enzyme activity which was found to be proportional to the intensity of the temperature gradient applied across the biocatalytic membrane, as well as to the average temperature of the bioreactor. The efficiency of such a non-isothermal bioreactor was calculated with respect to the yield of a bioreactor working under comparable isothermal conditions and was evaluated in terms of reduction of processing times in industrial applications. The possibility that enzyme activity in living cells is affected by non-isothermal conditions naturally existing owing to metabolic heat production is also discussed.

Bioreactors↗

PubMedDate not supplied

Enzyme reaction engineering: effect of methanol on the synthesis of antibiotics catalyzed by immobilized penicillin G acylase under isothermal and non-isothermal conditions.

The effect of methanol on the kinetically controlled synthesis of cephalexin by free and immobilized penicillin G acylase (PGA) was investigated. Catalytic and hydrophobic membranes were obtained by chemical grafting, activation, and PGA immobilization on hydrophobic nylon supports. Butyl methacrylate (BMA) was used as graft monomer. Increasing concentrations of methanol were found to cause a greater deleterious effect on the activity of free than on that of the immobilized enzyme. Methanol, however, improved the kinetic stability of cephalexin synthesized by free PGA, resulting in higher maximum yields. By contrast, immobilized PGA reached 100% yields even in the absence of the cosolvent. Cephalexin synthesis by the catalytic membrane was also performed in a non-isothermal bioreactor. Under these conditions, a 94% increase of the synthetic activity and complete conversion of the limiting substrate to cephalexin were obtained. The addition of methanol reduced the non-isothermal activity increase. The physical cause responsible for the non-isothermal behavior of the hydrophobic catalytic membrane was identified in the process of thermodialysis.

Anti-Bacterial Agents↗

PubMedDate not supplied

Stabilization of the restriction enzyme EcoRI dried with trehalose and other selected glass-forming solutes.

The stabilization of the restriction enzyme EcoRI by its incorporation into aqueous glass-forming carbohydrate or polymer solutions, followed by vacuum-drying to low moisture, has been studied. Glass-forming solutes included trehalose, sucrose, lactose, maltose, raffinose, maltodextrin DE 10, and poly(vinylpyrrolidone) (molecular weight 40,000, PVP). Among the solutes examined, trehalose and sucrose protected the enzyme most effectively during storage at 37 and 45 degrees C. The restriction enzyme dried with trehalose or sucrose maintained its activity without detectable loss for at least 20 days at 37 degrees C and 12 days at 45 degrees C. In contrast, the activity of the enzyme dried with maltodextrin or PVP was reduced during vacuum desiccation and also it decreased remarkably during storage at the same temperatures. Stored (37/45 degrees C) vacuum-dried trehalose and sucrose systems were either a dense paste or a very viscous syrup, and this indicated that they were not glassy. Moreover, no relationship was found between the glass transition temperatures (Tg) of the pure added solute and enzyme protection during storage, since, e.g., sucrose which has significantly lower Tg values protected the enzyme much better than either maltose, lactose, maltodextrin, or PVP. The trisaccharide raffinose offered good protection of enzyme activity, and its role as a novel excipient matrix for labile enzyme stabilization deserves further investigation. The stability of enzyme EcoRI was rapidly lost when the vacuum-dried trehalose and sucrose systems were humidified to 58% relative humidity and stored at 45 degrees C, and this was attributed to disaccharide crystallization.

Deoxyribonuclease EcoRI↗

PubMedDate not supplied

Vascular risk factors linked to multiple lacunar infarcts.

BACKGROUND: The pathogenesis of lacunar infarcts is still incompletely established. Data from the literature suggest that vascular risk factors differ among patients with multiple (MLI) and single lacunar infarcts (SLI). We reexamined this hypothesis using stricter inclusion criteria and a less selected study population. METHODS: We evaluated 136 patients consecutively admitted for first-ever minor stroke to a general hospital with the characteristics of a community hospital. Vascular risk factors were studied by univariate and multivariate statistical analyses among the following subgroups of patients, classified according to CT findings: (a) with lacunar infarct; (b) with nonlacunar infarct (NLI); (c) with SLI; (d) with MLI; (e) with single, either lacunar or nonlacunar, infarct. RESULTS: No significant difference was observed between patients with lacunar infarcts and patients with NLI. Compared to patients with SLI or NLI, patients with MLI had significantly more often a family history of hypertension, cardiomegaly on the chest radiograph and CT leukoaraiosis as well as a higher systolic and diastolic blood pressure on admission. Logistic regression analysis selected CT leukoaraiosis, Rx cardiomegaly and admission diastolic blood pressure as independent, significant predictors of MLI. CONCLUSION: In patients with first-ever minor stroke, the risk factor profile differs according to the evidence of SLI or MLI on the CT scan. In terms of risk factors, patients with SLI seem more similar to those with NLI than those with MLI. Based on the predicting effect of variables linked with type and severity of arterial hypertension, the CT appearance of MLI might express a more univocal and specific cerebrovascular pathology (hypertensive arteriolosclerosis).

Aged↗