A two-axis goniometer for low-temperature nuclear magnetic resonance measurements on single crystals.

We report on the construction of a two-axis goniometer intended for low-temperature, single-crystal nuclear magnetic resonance (NMR) measurements. With the use of home-made and commercially available parts, our simple probe-head design achieves good sensitivity, while maintaining a high angular precision and the ability to orient samples also when cooled to liquid helium temperatures. The probe with the goniometer is adapted to be inserted into a commercial (4)He-flow cryostat, which fits into a wide-bore superconducting solenoid magnet. Selected examples of NMR measurements illustrate the operation of the device.

Delay of type I diabetes in high risk, first degree relatives by parenteral antigen administration: the Schwabing Insulin Prophylaxis Pilot Trial.

The Schwabing Insulin Prophylaxis Trial is a randomised, controlled pilot study designed to examine whether insulin therapy can delay or prevent the clinical onset of Type I diabetes in high risk first degree relatives of people with the disease. First degree relatives of patients with Type I diabetes, who were aged 4 years or more, had an islet cell antibody (ICA) value more than 20 Juvenile Diabetes Foundation Units (JDF-U), a reduced first phase insulin response (FPI) to an i.v. glucose tolerance test less than the 5th centile, and a normal oral glucose tolerance test were eligible for the trial. Between January 1989 and October 1995, 1736 relatives of patients with Type I diabetes were screened for ICA. We identified 64 cases (3.7%) with ICA values more than 20 JDF-U. Of ICA positive relatives, 17 (27%) had a low FPI and were eligible for enrolment. Of these 14 agreed to participate, of whom 7 were randomised to the treatment group and 7 to the control group. In the treatment group, human insulin was administered i.v. by continuous infusion for 7 days, followed by daily s. c. injections for 6 months. Intravenous insulin infusions were repeated every 12 months. In the treatment group 3 of the 7 individuals (follow-up from time of eligibility: 2.3 to 7.1 years) and in the control group 6 of the 7 untreated individuals (1.7 to 7.1 years) developed clinical diabetes. Life table analysis showed that clinical onset of Type I diabetes was delayed in insulin-treated subjects compared with control subjects (means+/-SEM diabetes-free survival: 5.0+/-0.9 years vs 2.3+/-0.7 years, p < 0.03). Insulin levels after i.v. glucose increased in the first year of intervention therapy. Titres of ICA, and antibodies to glutamic acid decarboxylase, and tyrosine phosphatase-like protein IA2 remained unchanged. These data suggest that insulin prophylaxis can delay the onset of overt diabetes in high risk relatives. This is encouraging in view of 1) the continuing American Diabetes Prevention Trial, which is currently testing the effect of parenteral insulin in a large nation-wide study and 2) the initiation of pilot trials to determine whether new antigen-specific intervention is more effective in delaying the clinical onset of Type I diabetes.

ACE-inhibition with perindopril in essential hypertensive patients with concomitant diseases. The Perindopril Therapeutic Safety Collaborative Research Group.

PURPOSE: Many hypertensive patients have other, usually long-term diseases. Antihypertensive therapy may interfere with these diseases and their therapies. In the present study, the possible interactions of the ACE-inhibitor perindopril with several of the most common long-term diseases was evaluated. PATIENTS AND METHODS: In a multicenter, double-blind, randomized, placebo-controlled trial, the effect of perindopril was evaluated in 490 patients with mild essential hypertension and any one of the following concomitant diseases: hyperlipidemia, type II diabetes mellitus, ischemic heart disease, cardiac arrhythmia, peripheral arterial occlusive disease, nephropathy with proteinuria, chronic obstructive pulmonary disease, or degenerative joint disease treated with nonsteroidal anti-inflammatory drugs (NSAIDs). After a 3-week single-blind placebo run-in, the patients received either perindopril (4 mg/d) or matching placebo for 6 weeks. RESULTS: Blood pressure was effectively reduced by perindopril irrespective of the associated disease. The rate of spontaneously reported side effects was low. Treatment with perindopril was free from adverse interactions with the concomitant diseases and therapies. Moreover, favorable actions could be observed in patients with ischemic heart disease (reduction of maximal ST-segment depression during peak exercise and decrease in the number of angina attacks), in patients with proteinuria (decrease in albuminuria in patients with normal serum creatinine levels), and in patients with NSAID-treatment (increase in prostaglandin E2 concentration in gastric mucosa suggesting gastric cytoprotection). CONCLUSION: This trial shows that ACE-inhibition with perindopril represents a simple, safe, and effective short-term therapeutic option for the large proportion of patients with mild essential hypertension and concomitant diseases and therapies.

Silicone replica technique and automatic confocal topometry for determination of corneal surface roughness.

No method for the objective measurement of corneal surface roughness has thus far been available for experimental and clinical investigations. The surface roughness of photoablated porcine corneas was investigated with the silicone-cast method and automatic confocal topometry. Photoablation was performed with the 193-nm excimer laser. Surface roughness was determined as a function of the repetition rate (2-60 Hz; fluence, 180 mJ/cm2; beam diameter, 2 mm; 300 laser pulses/experiment). Immediately after photoablation, a silicone replica of the ablated surface was made and analyzed later using confocal topometry. The surface roughness for excimer laser ablation was found to be frequency-dependent: 0.4-0.6 +/- 0.08 micron (2-30 Hz) and 1.2 +/- 0.12 micron (60 Hz). The silicone cast of the cornea of a healthy eye gave an exact image of the profile and curvature: the difference between radius measurements of the cornea (Zeiss ophthalmometer) and of the silicone cast (laser topometer) was about 0.5%. As the silicone-cast method can also be used for in vivo animal experiments, the correlation between surface roughness and laser repetition rate can be studied with regard to photorefractive keratectomy.

[Silicone impression procedure. Principles for determining ablation and healing parameters in vitro and in vivo]. / Silikonabgussverfahren. Grundlage zur Bestimmung von Ablations- und Heilungsparametern in vitro und in vivo.

Topometry and measurement of photoablation patterns are key questions for keratorefractive photoablation. So far, ablation rates have been determined either by tissue perforation or histological micrometry. A cast of irradiated cornea was made by using a 2-component silicon that polymerizes within minutes, thus preserving the corneal topography immediately after photoablation. The silicon surface is extremely smooth and the accuracy of the cast better than 1 micron. Reproducibility and long-term stability were proven for casts of photoablated PMMA. Thus ablation rates and profile, volumetry and topometry can be determined at any time. The method was applied for 193 nm excimer and 2.94 microns Er:YAG laser in vitro irradiation of the human cornea. Ablation rates in Bowman's layer and stroma were observed for various radiant energies and distinct pulse numbers. The average ablation rates are in agreement with published data. It could be demonstrated that there was an incubation effect for the first pulses. The method feasibility for in vivo measurement was also proven in an animal model. After excimer photoablation in rabbit eyes (beam diameter 3.5 mm, radiant energy 185 mJ/cm3, ablation rate 0.3 micron/pulse), wound healing was recorded: for the right eye silicon casts were molded at three different moments. For the left eye only photographs were taken. There was no difference in the time course of wound healing, so the silicon does not seem to interfere with repair mechanisms of the corneal epithelium. No side effects were observed.

[Combination therapy of oral antidiabetic drugs with insulin]. / Kombinationstherapie von oralen Antidiabetika mit Insulin.

The treatment of type II diabetes should not only concentrate on blood glucose levels but also should take symptoms like insulin resistance, hyperinsulinemia, low HDL-cholesterol, high VLDL, and systemic hypertension into consideration. These symptoms are well described by the metabolic syndrome and are known to be risk factors of macroangiopathy. In obese type II diabetic patients weight loss by caloric restriction is the most essential therapeutic step. Retarding intestinal carbohydrate uptake glucosidase-inhibitors are able to lower postprandial blood glucose levels without stimulating insulin secretion. The biguanide metformin is suitable to diminish peripheral insulin resistance, gluconeogenesis, and intestinal glucose absorption on cellular mechanisms others than betacytotropic effects. In non obese type II diabetic patients sulfonylureas are advantageous because of meal related stimulation of endogenous insulin which runs the physiological way with first pass through the liver. Therefore, sulfonylurea treatment should be continued when secondary failure indicates the need for exogenous insulin. In accordance with the course of type II diabetes in secondary failure insulin should be added to sulfonylureas in as small amounts as possible to ameliorate poor metabolic control. Thus iatrogenic hyperinsulinemia and resulting insulin resistance can be largely avoided. If there is any long term benefit when different oral antidiabetic agents are administered together with insulin has to be evaluated in further clinical studies.

[A new method for diagnostic-therapeutic evaluation of rhinomanometry results]. / Eine neue Methode zur diagnostisch-therapeutischen Bewertung rhinomanometrischer Ergebnisse.

We have developed a new method for the clinical evaluation of nasal permeability by comparing flow (Vt) and subjectively estimated patency (D). In a coordinate system Vt is marked on the y-axis and D is recorded on the x-axis. The y-axis is separated into an operative and a non-operative part. The limit of Vt is 700 cm3/s. Four quadrants are produced, in which quadrant I is a conformity between the non-operative part of the flow and the value estimated by the patient (showing that no operative intervention is indicated). Conformity between the operative part and estimated value in quadrant III means that an operation is indicated. Discrepancies exist in quadrants II and IV and designate conservative therapy. Since clear directions for treatment are possible from each quadrant, the principle is easily programmable for use in a microprocessor, which is small and portable.

Silicon cast method for quantification of photoablation.

BACKGROUND: Topometry and measurement of photoablation patterns are key questions for keratorefractive photoablation. Ablation rates have been determined previously by either tissue perforation or by micrometry performed on histologic sections. METHODS: A three-dimensional cast of cornea after irradiation was made by using a two-component silicon gel that polymerizes within minutes, thus preserving the corneal topography immediately after photoablation. Polymerization is athermal and nontoxic. The resulting silicon blocks were cut perpendicularly to the anterior surface and measured by calibrated light microscopy. RESULTS: The silicon surface is extremely smooth and the accuracy of the cast is better than 0.25 micron. Reproducibility and long-term stability were demonstrated for casts of photoablated polymethylmethacrylate. Thus, ablation rates and profile, volumetry, and topometry can be determined following laser ablation. The method has been applied for 193-nanometer excimer laser in vitro irradiation of the human cornea. Ablation rates in Bowman's layer and stroma for various radiant energies and distinct pulse numbers were found to be in agreement with published data, and an incubation effect for the first laser pulses could be demonstrated. CONCLUSIONS: The method is nondestructive, accurate, inexpensive, practical, and reduces requirements for laboratory animals.

[Intraocular availability of liposome encapsulated monoclonal antibodies in the rabbit model. Results of a pilot study]. / Intraokulare Verfügbarkeit liposomenverkapselter monoklonaler Antikörper im Kaninchenmodell. Ergebnisse einer Pilotstudie.

The results of local application of monoclonal antibodies (mAb) in rabbit eyes are presented. To improve intraocular access of the high-molecular-weight protein it was entrapped in large (0.2 microns) unilamellar, negatively charged liposomes. Concentrations of the free or encapsulated drug were measured by ELISA in different eye compartments following repetitive drop administration or single subconjunctival injection. Although mAb became measurable in specimens of conjunctiva and cornea, it was not detectable (less than 0.5 ng/ml) in aqueous humor, lens or the vitreous body. In contrast, concentrations of the liposome-encapsulated drug were measurable as little as 30 min after topical application in the aqueous humor.

[The structure of the morbidity among people working at computers with video display terminals]. / Struktura zabolevaemosti u rabotaiushchikh na EVM s videodispleinymi terminalami.

The authors analyzed data of ane examination of 407 user of video display terminals of large computer centers in Kiev and revealed high morbidity of the circulatory digestive and locomotor organs. An analysis of 878 analogous cases in the GDR revealed lower involvement of the mentioned organs. Causes are analyzed. Ways of prophylaxis are outlined.

[Laser-induced occlusion of corneal blood vessels with variable emission and absorption]. / Laserinduzierte Hornhautgefässokklusion bei variabler Emission und Absorption.

Laser light has repeatedly been proposed for the occlusion of corneal neovascularizations. Priority has to be given to minimize laser energy in order to limit side effects such as corneal burns. We investigate the influence of variable emission wavelength using a dye laser or dye-enhanced absorption with intravenous sodium fluorescein. Laser energy can be reduced using intravenous dyes at vessel diameters less than 50 microns. Permanent occlusion is achieved in 43% instead of 28% without dye-enhanced absorption. Vessels measuring greater than 50 microns in diameter can be occluded best at lowest laser energy levels when 575 nm laser light is used, which approximates the absorption maximum of hemoglobin.

[Combination therapy with insulin/sulfonylurea in the long-term therapy of type II diabetes following "secondary failure"]. / Die Kombinationstherapie Insulin/Sulfonylharnstoff in der Langzeittherapie des Typ-II-Diabetes nach "Sekundärversagen".

In type 2 diabetes with "secondary failure of sulfonylurea therapy" good metabolic control can seldom be achieved by insulin therapy even with high insulin doses. Hyperinsulinemia however is a possible risk factor of cardiovascular disease in type 2 diabetes. Maintaining the effects of sulfonylurea action insulin should be added in as small amounts as possible to avoid hyperinsulinemia and to ameliorate hyperglycemia. 16 type 2 diabetics with "secondary failure" were treated either with insulin alone (group A; n = 8) or with 3.5 mg b.i.d. glibenclamide plus small amounts of intermediate insulin (group B; n = 8) in a randomised order. After the inpatient period outpatient control was performed monthly up to six months, later on four times a year up to two years. Both groups were comparable with regard to age, duration of diabetes, body weight and metabolic control. The daily insulin dose was 14 +/- 2 IU (means +/- SEM) after one month and 19 +/- 2 IU after two years in group B. In contrast 30 +/- 3 IU and 43 +/- 5 IU respectively were needed in group A (p less than 0.001). All patients B were treated with one daily injection, all patients A needed two injections. Resulting in nearly identical metabolic control in group A basal insulin levels exceeded those in group B after two years significantly (28.6 +/- 3.7 vs. 18.6 +/- 1.6 mcU/ml; p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Strategy for the primary and secondary prevention of occupational diseases in the German Democratic Republic.

This review explains the German Democratic Republic's strategy for preventing occupational diseases, which is considered one of the primary purposes of public health. It is a complex challenge that is being tackled through close cooperation between enterprise-linked occupational health services, the inspectorates of industrial hygiene, public health centers, and trade unions. In primary prevention, planning is based on results obtained in thorough analyses of all the relevant parameters, such as work conditions, industrial accidents, occupational diseases, morbidity records, and the quality of social services, and a complex work analysis has been developed to provide comprehensive and measurable information on health hazards due to harmful physical and chemical factors, dust, and job-related physical and neuropsychic stresses. Primary prevention is realized mainly through the elimination of health hazards and the improvement of work conditions, both based on a comprehensive framework of legislation. At the level of secondary prevention, company-linked occupational health services are a part of the national health services. A nationwide information system consists of compatible components for primary and secondary prevention, thus enabling control of exposure-effect relationships and the optimization of health policy.