[Economic aspects of use of alternative dental alloys]. / Betriebswirtschaftliche Aspekte des Einsatzes alternativer Dentallegierungen.

A cost calculation for different types of dental alloys was carried through all stages of production. Recycling and scrap material values were included. Results showed that over an estimated 20 years of usage, the higher annual cost for bridges cast with a high gold alloy in relation to those with lower gold content alloys is not that significant that from the patients point of view the lower alloys should the choice. Due to the system of health insurance, this cost calculation from the production point of view looks different for the organizations that are reimbursing the patient for his expenses, as these organizations are not entitled to the scrap value of old restorations.

[Long-term results following argon laser trabeculoplasty]. / Langzeitresultate nach Argonlaser-Trabekuloplastik (ALT).

Long-term follow-up findings after argon laser trabeculoplasty are communicated. The coagulation technique employed was that described by Wise and Witter (1979). The circumference of the chamber angle was coagulated over 360 degrees. The indications were chronic open-angle glaucoma, pseudoexfoliation glaucoma, pigmentdispersion glaucoma, glaucoma in aphakia, and glaucoma after ALT or fistulizing surgery with uncontrolled IOP. Glaucoma cases in which IOP exceeded 35 mm Hg were not treated by this method. Therapy was considered successful if a decrease in IOP to below 20 mm Hg was achieved. The difficulties of finding appropriate parameters for the success of glaucoma therapy are discussed. The percentages of normotonic eyes after ALT with a follow-up period of one to four years are reported and compared with results obtained by other authors. After one year, IOP was normal in 89.9% of 881 eyes (chronic open-angle glaucoma 94%, pigment-dispersion glaucoma 91%, pseudoexfoliation glaucoma 86%, glaucoma in aphakia 88%). After two years, it was normal in 72.6% of 237 eyes (chronic open-angle glaucoma 82%, pigment-dispersion glaucoma 50%, pseudoexfoliation glaucoma 53%, glaucoma in aphakia 75%). After three years, it was normal in 60.5% of 76 eyes (chronic open-angle glaucoma 72%, pigment-dispersion glaucoma 25%, pseudoexfoliation glaucoma 37%, glaucoma in aphakia 66%). After four years, it was normal in 95.4% of 128 eyes (chronic open-angle glaucoma 82%, pseudoexfoliation glaucoma 50%). The results of ALT therapy reported by other authors are similar. A decrease in efficiency, initially of 5% to 10% per year, is seen in eyes thus treated, which may necessitate fistulizing surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

[Argon laser trabeculoplasty. Initial results of a prospective study]. / Argonlasertrabekuloplastik. Erste Erfahrungen aus einer prospektiven Untersuchung.

This paper presents the results of a prospective study on argon laser trabeculoplasty with clinical application in 166 cases up to now. So far, patients have been followed up for between 2 and 12 months. Low-intensity coagulation was performed over 360 degrees of the trabecular meshwork. The coagulation site within the trabecular meshwork was chosen according to the outflow facility as measured by tonography. In eyes with high outflow facility (C greater than 0.08) the unpigmented, so-called nonfunctioning trabecular meshwork was coagulated. Where the outflow facility was lower (C less than 0.03), a pigmented area of the trabecular meshwork was aimed at. Where the facility was intermediate (0.08 greater than C greater than 0.03) the border area between pigmented and nonpigmented meshwork was coagulated. Three groups of patients were treated: (1) older patients with insufficient compliance; (2) patients whose intraocular pressure (IOP) was poorly controlled by drugs and was under 35 mm Hg; (3) patients suffering from glaucoma in aphakia or status post trabeculectomy and poor control of IOP. Applying these criteria , IOP was controlled in 26.8% without additional drugs and in 68% in combination with local medication after 6 weeks. Very few complications were seen (8 cases), and they did not lead to deterioration or loss of vision. In the light of theoretical considerations and initial histopathologic findings in human eyes, the authors assume that low-intensity coagulation causes a denaturation and shrinkage of the trabecular collagen, leading to stretching of the surrounding trabecular structures.(ABSTRACT TRUNCATED AT 250 WORDS)

Functional differentiation of the medullary collecting tubule: influence of vasopressin.

Medullary collecting tubules of rabbits were dissected from the outer zone at different stages of ontogenetic evolution and perfused in vitro. The hydraulic conductivity coefficient (Lp) was measured in the presence of either hypotonic perfusate and isotonic bath or isotonic perfusate and hypertonic bath. Basal Lp (cm s-1 atm-1 10(-7) was 85 +/- 34 (N = 17) during early functional differentiation of the outer medullary collecting tubule (e-OMCT), 36 +/- 6 (N = 8) in the intermediate state (i-OMCT), and 10 +/- 7 (N = 11) in the final, mature state of function (m-OMCT). Addition of supramaximal concentrations of arginine-vasopressin (AVP) to the bath increased Lp in i-OMCT (250 +/- 36) and m-OMCT (327 +/- 63) but did not activate the osmotic hydraulic conductance in e-OMCT (105 +/- 27). In 11 studies, OMCT were analyzed using isotonic solutions as the perfusate and bath medium. The spontaneous transtubular voltage (PD) was lumen positive, 1.71 +/- 0.3 in e-OMCT, lumen negative 2.43 +/- 0.3 in i-OMCT, and 6.1 +/- 0.4 in m-OMCT. AVP had no effect on PD in e- and i-OMCT but increased the PD significantly (P less than 0.025) to 9.2 +/- 0.6 in m-OMCT. The results indicate that both hydraulic conductivity coefficient and transtubular voltage in the medullary collecting tubule are dependent upon epithelial ontogeny and, particularly, display differential responses to the antidiuretic hormone. The data suggest that the differentiation of water and ion transport in the medullary collecting tubule may contribute to the increasing efficacy of the medullary countercurrent system.

Maturation of diluting capacity in loop of Henle of rat superficial nephrons.

The postnatal development of renal diluting capacity was studied by free-flow micropuncture and by microdissection of single superficial loops of Henle in rats kept on a high salt diet. Total renal filtration rate, sodium absorption, total solute excretion, and systemic arterial pressure were monitored during single nephron evaluation at two maturational stages (12-15 days and 27-35 days postnatal). Nephron filtration rates were identical when measured in early distal and late proximal segments of the same nephron. Absolute fluid absorption between these sites increased by a factor of 2.5, whereas loop fractional absorption of the volume load changed from 38.1 +/- 6.9 to 49.8 +/- 4.8% (SD), while proximal volume delivery to the loop increased from 4.33 +/- 1.12 to 7.14 +/- 0.65 nl/min. Simultaneously, the osmolarity of early distal fluid (8.8% of distal length) decreased significantly from 284 + 19.8 to 180.9 +/- 18.2 mosmol/liter during maturation. This study suggests that the ability of the loop of Henle to generate hypotonic fluid is attained only gradually during ontogeny. Volume absorption in the loop of Henle increases disproportionately to the loop volume load.

Visual recovery after central retinal artery occlusion: two cases.

Two cases of central retinal artery occlusion of prolonged duration (greater than 6 hours) were treated with retrobulbar anesthesia, anterior chamber paracentesis, and high-dose carbon dioxide and oxygen inhalation. Both cases recovered excellent vision and illustrate that visual recovery after relatively prolonged central retinal artery occlusion is possible.

Comparison of in vitro corticosteroid response in pigmentary glaucoma and primary open-angle glaucoma.

We used an in vitro assay utilizing corticosteroids to inhibit transformation of peripheral blood lymphocytes to evaluate a group of 20 patients with pigmentary glaucoma. The pigmentary glaucoma patient group did not manifest the markedly increased cellular sensitivity to corticosteroids associated with primary open-angle glaucoma. If increased sensitivity to corticosteroids plays an essential role in the pathogenesis of primary open-angle glaucoma, then pigmentary glaucoma appears to be etiologically, as well as clinically, a separate entity.

In vitro determination of relative corticosteroid potency.

The corticosteroid concentration required to inhibit phytohemagglutinin stimulated human lymphocyte transformation by 50% was determined for three corticosteroids. The relative potency of hydrocortisone, prednisolone and dexamethasone determined in 16 patients was 1.00, 2.43, and 24.7 respectively. This assay is proposed as an objective tool for comparison of relative corticosteroid potency in man.

Modification by imidazoles of ocular inflammatory and pressure responses.

Imidazole, given intraperitoneally to rabbits, inhibited the prostaglandin E1-induced (PGE1) elevation of intraocular pressure. The maximum imidaz-le effect occurred at three to six hours after intraperitoneal infection. The prostaglandin E1-induced aqueous humor protein elevation was reduced markedly in the imidazole-pretreated rabbits. Intravenous administration of imidazole also was effective in reducing the intraocular pressure elevation produced by prostaglandin E1. Imidazole pretreatment by subconjunctival, subdermal, or topical routes had no such effect. Imidazole derivatives, 1-methylimidazole and 2-methylimidazole, given intraperitoneally, blocked the effect of PGE1 on intraocular pressure and aqueous humor protein. Imidazole pretreatment also inhibited the elevation of intraocular pressure produced by topical nitrogen mustard, 1 per cent.

In vitro corticosteroid: correlation response with primary open-angle glaucoma and ocular corticosteroid sensitivity.

The transformation of human peripheral blood lymphocytes can be inhibited by corticosteroid compounds. In an in vitro study of 100 patients with primary open-angle glaucoma and various degrees of ocular pressure responsiveness to corticosteroid testing, varying degrees of sensitivity to corticosteroid compounds existed systemically in the circulating lymphocyte. A high correlation exists between the level of corticosteroid sensitivity in the lymphocyte and in the eye. In vitro cellular systems may be useful in evaluating the molecular basis of the variability in corticosteroid response, and in understanding the pathogenesis of corticosteroid-induced ocular hypertension and primary open-angle glaucoma.