Acute aortic syndromes

The term acute aortic syndrome comprises in addition to classic dissection also two recently described entities--penetrating ulcer and intramural haematoma. Forty-two necropsy cases of acute aortic syndrome were encountered during the last six years--41 dissections and one penetrating ulcer; the intramural haematoma was not seen. According to the DeBakey classification, there were 26 dissections of type I, 8 of type II, 1 of type IIIA, and 4 of type IIIB; in 2 cases the dissection was confined to the abdominal aorta. The dissection had a chronic character in four cases. Aortic rupture was found in 24 cases (59%), most frequently (19x) into the pericardial cavity. The aortic dissection continued into aortic branches in 25 patients (61%), causing stenosis/obstruction of coronary arteries in 7, of branches of the arch in 20, of abdominal arteries in 12, and of renal arteries in 17 patients, respectively. Histologically, there were degenerative lesions of the Erdheim type in the media of 10 aortas (from 21 completely examined). As possible risk factors for aortic dissection there appeared hypertension in 32 patients, anuloaortic ectasia in 11, saccular aneurysm ot the abdominal aorta in 6, family history of dissection in 2, Marfan syndrome in 2, prolaps of the mitral valve in 2, and bicuspid aortic valve in 2 patients, respectively. The aortic dissection was iatrogenic in 7 patients, presenting as a complication of a cardiosurgical or invasive cardiological procedure.     

Bloom''s Syndrome. VII. Progress report for 1978

The Bloom's Syndrome Registry was published in this journal in 1977. Now, in the first in a series of progress reports, recent accessions to the Registry are recorded, new instances of neoplasia are listed, and recent clinical observations and experimental results of general interest are cited.     

Ten novel HLA-DRB1 alleles and one novel DRB3 allele

Ten novel HLA-DRB1 and one DRB3 alleles are described. Eight of the variants are single-nucleotide substitutions, four resulting in an amino acid change (DRB1*1145, *1148, *0828 and *1514) and four with silent substitutions (DRB1*040504, *130103, *160502 and DRB3*020204). Two alleles differ by two nucleotide changes altering one (DRB1*1447 and *1361) amino acid and one allele alters three nucleotides and two amino acids.     

Effect of various diuretics on membrane voltage of macula densa cells. Whole-cell patch-clamp experiments

The tubuloglomerular feedback mechanism is inhibited by diuretics such as furosemide. For the macula densa (MD) cells similar transport systems, as present in thick ascending limb (TAL) cells, have been suggested. To examine this further, membrane voltages (V _m) of MD cells were recorded with the fast or slow wholecell patch-clamp method. The effects of diuretics on voltages and the conductance properties of these cells were examined. V _m of MD cells measured with the whole-cell patch-clamp method were as high as those in TAL cells: –72±1 mV (n=21). An increase in the extracellular K⁺ concentration by 15 mmol/l depolarized V _m of MD cells by 11±1 mV (n=18). Ba²⁺ (1 mmol/ l) reversibly depolarized MD cells by 10±2 mV (n= 10). Thus, MD cells possess a K⁺ conductance that could allow for the recycling of K⁺ taken up by the Na⁺-2 Cl^–-K⁺ cotransporter. MD cells hyperpolarized reversibly upon addition of the loop diuretics furosemide, piretanide and torasemide, whereas muzolimine and hydrochlorothiazide, neither one acting on this cotransport system in other preparations including the TAL, had no effect on V _m. MD cells most likely possess the same cotransport system as the TAL cells, which drives NaCl reabsorption in the TAL and serves as sensor for the tubular NaCl concentration in MD cells.     

Current Biotechnological Approaches to the Prevention of Restenosis

No systemic pharmacological treatment has been convincingly shown to reduce the incidence of restenosis after angioplasty in patients. The lack of success of many pharmaceutical agents in reducing restenosis rates post-angioplasty and following stent implantation, as documented in dozens of clinical trials, has encouraged the development of new biotechnological approaches to the treatment of restenosis. Gene therapy and other agents, including antibodies, fusion toxins and ribozymes, have the potential to prevent some of the sequelae after arterial injury, particularly cell proliferation. Mechanical methods of preventing restenosis, for example sophisticated local drug delivery strategies and biodegradable stents using new materials, in combination with novel therapeutic agents or radiation, may also be of use.     

Predominantly cerebral manifestation in Urbach-Wiethe's syndrome (lipoid proteinosis cutis et mucosae): a clinical and pathomorphological study

The neurological and psychiatric manifestations in a case of Urbach-Wiethe's disease are reported. The present case is characterized by the predominance of cerebral symptoms: ataxia, psychomotoric seizures, paranoic hallucinatory psychosis and attacks of rage. At autopsy, deposits of amyloid-like material in the walls of the brain vessels could be observed. This finding, together with the mucocutaneous alterations, confirmed the diagnosis of the rare disease know as "lipoid proteinosis cutis et mucosae".     

The effect of propranolol on exercise induced tachycardia is determined by plasma concentration and the density of adrenergic receptors on leukocytes

Summary The chronotropic response to a single oral dose of propranolol in 23 healthy subjects has been related to the plasma propranolol concentration and the density of -adrenoceptors on peripheral polymorphonuclear leucocytes. The percentage reduction in exercise-induced tachycardia was significantly correlated with the log plasma propranolol concentration within subjects but not between subjects. Taking the concentration of the active metabolite 4-hydroxypropranolol into account did not improve the interindividual correlation. The reduction in exercise-induced tachycardia was significantly correlated with the maximum binding density of (¹²⁵I)-hydroxybenzylpindolol on polymorphonuclear leucocyte membrane fragments measured before medication. A response index (% reduction in exercise-induced tachycardia/plasma propranolol concentration) was correlated with the maximum binding density of (¹²⁵I)-hydroxybenzylpindolol (predrug) at 2 h (r_s=0.72), 4 h (r_s=0.84) and 6 h (r_s=0.73) after dosing. The data suggest that interindividual variation in the response to propranolol after a single oral dose is determined by interindividual differences both in plasma propranolol and adrenoceptor density.     

Deciphering the molecular effects of non-ablative Er:YAG laser treatment in an in vitro model of the non-keratinized mucous membrane

Lasers in Medical Science -