Microelectrode array sensor for water quality monitoring.

A versatile microelectrode array sensor for water quality monitoring has been developed. The array fabrication, based on batch microelectronic processes, results in a highly stable passivation of the silicon chip surface and provides the possibility to use a backside contact. Packaging was optimized for on-line water operation at high pressures. Examples of applications include chlorine monitoring in drinking water, ozone monitoring in deionized water, dissolved oxygen in activated sludge and preliminary measurements of trace arsenic.

Effect of fluvastatin on lipids and fibrinolysis in coronary artery disease.

This randomized, double-blind, placebo-controlled study shows that 20-week fluvastatin treatment induces beneficial changes in the lipid panel and a shift in the fibrinolytic pathway toward activation through a decrease in tissue plasminogen activator antigen. Fluvastatin treatment causes no variation in lipoprotein(a) circulating levels.

Affinity of angiotensin I-converting enzyme (ACE) inhibitors for N- and C-binding sites of human ACE is different in heart, lung, arteries, and veins.

Angiotensin-converting enzyme (ACE) has two enzymatically active domains: a C-domain in the carboxy terminal region and an N-domain in the amino terminal region. We based the pharmacologic characterization of these sites on the rat testis-lung model. In testis, only a truncate form of ACE is present (C-site), whereas both N- and C-sites are present in lung. In this model, captopril was shown to be N-selective and delaprilat to be C-selective. Ro 31-8472, a cilazapril derivative, and enalaprilat proved to be not site selective. We used these drugs to evaluate the affinity of C and N sites in various human tissues involved in the cardiovascular actions of ACE and used [125I]Ro31-8472 as ligand. The number and affinity of ACE binding sites were 17,680 +/- 2,345 fmol/mg protein (Kd = 0.32 +/- 0.04 nM) in lung, 560 +/- 65 (Kd = 0.36 +/- 0.05 nM) in heart, 237 +/- 51 (Kd = 0.37 +/- 0.06 nM) in coronary artery, 236 +/- 63 (Kd = 0.14 +/- 0.05 nM) in saphenous vein, and 603 +/- 121 (Kd = 0.50 +/- 0.06 nM) in mammary artery. The affinity (pKi) of captopril for the N sites ranged from 9.40 +/- 0.14 (lung) to 8.41 +/- 0.10 (coronary artery). The affinity for the C-site by delaprilat ranged from 9.97 +/- 0.15 (coronary artery) to 9.10 +/- 0.14 (mammary artery). Therefore, the affinity of C- and N-sites of ACE for ACE inhibitor (ACEI) drugs is different according to the organ involved. Because ACE is a glycosylated enzyme and glycosylation is organ dependent, we suggest that organ-specific glycosylation affects the binding characteristics of ACE inhibitors to N- or C-site of human tissular ACE.

University of Wisconsin solution and human saphenous vein graft preservation: preliminary anatomic report.

Endothelial damage of human saphenous vein (HSV) during the preparation for bypass grafting could affect graft patency. Improving the preservation of HSV could provide a longer and better patency of coronary artery bypass grafts. An electron microscopic comparative analysis of the effects of three different preservatives on HSV morphology was carried on in order to determine the best method to prevent or minimize possible endothelial damage. Distal segments of HSVs were harvested from 15 patients with a "no-touch" technique. Each segment was divided into seven specimens after a low pressure distension with saline solution. The first of them was fixed immediately after harvesting with 2.5% glutaraldehyde solution, for basal evaluation. Three were fixed after 30 min and three after 5 h preservation at 4 degrees C in a) autologous, oxygenated, and heparinized blood (AOHB), b) heparinized saline solution with papaverine (HSSP) and c) University of Wisconsin solution (UWS). The specimens preserved in AOHB showed marked endothelial cell detachment and endothelial cell loss after both preservation times (30 min and 5 h). The specimens preserved in HSSP for 30 min showed no alteration in endothelium in 12 cases, while a partial endothelial detachment with intracellular edema was present in the last 3 cases; all 5 h specimens showed only a few remnants of endothelial cells. The specimens preserved in UWS for 30 min showed a morphology comparable to specimens preserved in the saline solution for the same time; in the 5 h specimens a well preserved endothelium was found in 11 cases and partial endothelial detachment and subendothelial edema in the other 4.(ABSTRACT TRUNCATED AT 250 WORDS)

Post transfusion hepatitis: comparison between homologous and autologous blood transfusion.

OBJECTIVES: To assess whether the use of autologous blood transfusion may affect the incidence of post-transfusion hepatitis in transfused patients who undergo cardiac surgery. METHODS: One thousand one hundred and twelve polytransfused patients having undergone cardiac surgery were studied from October 1982 through September 1990. Patients were transfused with homologous blood from selected volunteer donors; autologous blood collection or blood saving were introduced in September 1986. Routine laboratory tests were carried out upon hospitalization and monthly for a six-month period. Patients with hepatitis were followed for at least 24 months and liver biopsy was performed in those with chronic hepatitis. RESULTS: Ninety-four (9.8%) of the 959 polytransfused patients developed non-A, non-B post-transfusion hepatitis; anti-hepatitis C virus antibodies were present in 52 out of the 72 patients tested. The mean incubation period for post-transfusion hepatitis was 70 days; hospitalization was required in 47.9% of the patients. The mean number of transfused units was 12.9 in patients who developed post-transfusion hepatitis and 6.96 in the those who did not. Hepatitis was chronic in 42% of the 94 patients; in the others alanine aminotransferase levels normalized in a mean period of 10.3 months. None of the 237 patients who received autologous blood had hepatitis. CONCLUSION: In our study the role of surgical teams in preventing post-transfusion hepatitis was shown to be essential. The high percentage of chronicity and symptom-free hepatitis observed is a further reason to reduce homologous blood transfusions and instore careful follow-up of polytransfused patients.

Tracheal obstruction due to congenital tracheomalacia in a child. Case report.

Congenital tracheal obstruction, though not notably uncommon in infancy, is rarely due to isolated tracheomalacia, especially when characterized by complete absence of cartilaginous rings. A 5-year-old boy underwent successful tracheal resection and anastomosis following severe tracheal obstruction due to aplasia of cartilaginous rings.

[Autologous blood transfusion in elective heart surgery: prospective study of 189 consecutive patients]. / L'autoemotrasfusione in cardiochirurgia elettiva: studio prospettico in 189 pazienti consecutivi.

Blood autotransfusion has entered a new phase in blood transfusion technique, since it represents an important alternative in eliminating the risks connected with blood transfusion: viral hepatitis, AIDS, blood transfusion reactions, and alloimmunization. Transfusion requirements during cardiac surgical procedures have steadily decreased; nowadays most adult patients require no transfusion during surgery. Patients (pts) receiving bank-blood may develop infectious diseases (hepatitis, AIDS, etc.). We have studied how to avoid the risk of infections with homologous blood transfusions. We present our experience of day-hospital pre-operative autologous blood collection. One-hundred-eighty-nine patients undergoing primary myocardial revascularization or valvular replacement were submitted to the drainage of 350 ml of blood three times every four days before surgery. The blood was centrifuged at once, to separate red cells from plasma. Surgeries were performed 21 days after the first drainage; iron therapy was recommended. After surgery pts received blood only if haematocrit was lower than 28%. The following data were recorded: no. of pts who received homologous blood; blood loss and homologous total blood volume used for each pt. Average blood loss was 1230 cc for ischemic pts and 701 cc for valvular pts. Non-A non B hepatitis occurred in 3/189 pts (1.5%). All of them had received homologous blood transfusions. Our data show clearly that autotransfused pts had a better post-operative period; less bank-blood and fewer transfusions have been used. No pt had collateral effects such as angina or hypotension from blood drawing. Our data show that severe cardiac diseases do not represent an absolute contraindication to heavy blood drainage.(ABSTRACT TRUNCATED AT 250 WORDS)

[Primary tumors of the right ventricle: apropos of a case of hemangioendothelioma treated surgically]. / I tumori primitivi del ventricolo destro: a proposito di un caso di emangioendotelioma trattato chirurgicamente.

Primary tumours of the heart are uncommon and, among them, hemangioendotheliomas are exceptionally rare. The purpose of this paper is to present a rare case of right ventricular hemangioendothelioma treated surgically with success.

[Mitral insufficiency caused by floppy valve: results of conservative surgical treatment]. / Insufficienza mitralica da "floppy valve": risultati del trattamento chirurgico conservativo.

Between January 1986 and November 1987, 31 patients (pt.) underwent reconstructive surgery for mitral regurgitation secondary to floppy valve. Six pt. were in NYHA functional class IV, 22 in III class and 3 in II class. The mitral valve prolapse was posterior in 20 cases, anterior in 7 cases and bilateral in 4 cases. Chordal rupture was present in 18 pt. The mitral valve was repaired by quadrangular excision of the mural leaflet and posterior annuloplasty performed by insertion of polytetrafluoroethylene graft. The anterior prolapse was managed by transposition of chordae from the mural leaflet to the prolapsed part of the anterior leaflet (11 cases). One patient died perioperatively from myocardial infarction. Subsequent follow-up (length: 12.1 +/- 4.9 months) revealed good functional and clinical results: all pt. were alive, in NYHA class I or II (3 pt.). Echocardiographic studies revealed a decrease in diastolic (3.68 +/- 0.6 vs. 3.17 +/- 0.3 cm/m2) and systolic (2.4 +/- 0.5 vs. 2.15 +/- 0.4 cm/m2) diameter. The shortening fraction did not decline significantly. The mitral area fell from 6.0 +/- 2.0 cm2 to 3.1 +/- 1.1 cm2. A moderate residual regurgitation was present in two pt. and a severe regurgitation was found in only one pt. Our experience suggests that valve repair may be considered the most suitable type of operation for mitral regurgitation secondary to floppy valve.