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Die Dissertation präsentiert die Resultate zweier Studien, die unter Anwendung von zwei etablierten Methoden der Schwingungsspektroskopie erzielt wurden. Zunächst wird die Untersuchung von wässrigen Ytterbiumhalid-Lösungen mittels THz-Spektroskopie und Raman-Spektroskopie dargestellt. Hierbei konnten neue Erkenntnisse über das Ionenpaarbildungsverhalten von YbCl3 und YbBr3 gewonnen werden. Sowohl die THz-Spektren als auch die Raman-Spektren lieferten im Falle von YbCl\(_3\) deutliche Hinweise auf die Bildung von schwachen Kontaktionenpaaren, während dies für YbBr\(_3\) nicht beobachtet werden konnte. Die zweite Studie befasst sich mit der Raman-spektroskopischen Charakterisierung des mit Plasma behandelten Redoxpaars GSH und GSSG. Es konnten verschiedene oxidative und nitrosative Modifikationen von GSH und GSSG festgestellt werden, deren Entstehung in Abhängigkeit von der Plasmabehandlungsdauer analysiert wurde. Als Hauptprodukte wurden Glutathionsulfonsäure und S-Nitroso-Glutathion identifiziert.

PTB-Mitteilungen. Band 128 (2018), Heft 3. ISSN 0030-834X

An in Paul-Fallen gespeicherten Ionen lassen sich quantenmechanische Effekte untersuchen. Hierzu werden die internen Zustände der Ionen manipuliert und anschließend durch Fluoreszenzmessungen detektiert. Diese Experimente können für Anwendungen in der Quanteninformationsverarbeitung genutzt werden, Ziele hierbei sind beispielsweise die Simulation von Quantensystemen und die Verwirklichung eines Quantencomputers. Im Rahmen dieser Arbeit wird als Apparatur zum Speichern von Ytterbium-Ionen eine mikrostrukturierte segmentierte Paul-Falle verwendet. Durch den in die Falle integrierten Elektromagneten ist es möglich, die Ionen zu koppeln (Magnetic Gradient Induced Coupling - MAGIC) und mittels Mikrowellenstrahlung zu adressieren. Durch die segmentierten Elektroden können die Ionen innerhalb der Falle kontrolliert bewegt werden und es lässt sich deren Wechselwirkung einstellen. Ein mit Dickschichttechnik bedruckter Keramikblock dient als kompakte Vakuumdurchführung der über siebzig elektrischen Signale, die für den Betrieb der Falle benötigt werden. Alle weiteren für die Versuchsapparatur benötigten Komponenten wie der Vakuumrezipient und die Laserstrahlquellen wurden aufgebaut. Für die Erzeugung von Laserstrahlung bei 369 nm durch Frequenzverdopplung wird erstmals ein Bismuth-Triborat-Kristall genutzt. An den gespeicherten Ionen werden kohärente Rabi- und Ramsey-Messungen durchgeführt. Durch Messung der Energiedifferenz der einzelnen Zeeman-Niveaus lässt sich das Magnetfeld am Ort des Ions mit einer relativen Unsicherheit von einem ppm bestimmen. Ions trapped in a Paul trap make an ideal system to investigate quantum mechanical effects. To this end the initial states of the ions are manipulated and fluorescence measurements are used for detection. Such experiments have applications in quantum information processing, in particular in the simulation of quantum systems or the realization of a quantum computer. The Paul trap used to trap ytterbium ions in this thesis is a microstructured segmented trap. Electromagnets are integrated into this trap with which individual ions can be coupled to one another (Magnetic Gradient Induced Coupling - MAGIC) and addressed using microwave radiation. Controlled movement of the trapped ions and adjusting the coupling constant between the ions is possible using the segmented electrode structure. A compact vacuum feed through system is realised using a thick film technique printed onto a ceramic block. More than seventy electric signals are used to control the trap using this feed through. Furthermore, the experiment requires a vacuum chamber and laser sources, all of which were constructed and installed during the course of this work. For the first time a bismuth triborate crystal is used for the generation of laser radiation at 369 nm by frequency doubling. First coherent measurements in the form of Rabi and Ramsey measurements are carried out on the trapped ytterbium ions. Measurement of the energy difference between individual Zeeman levels, allow to determine the ions local magnetic field with a relative uncertainty of one ppm.

Ill., graph. Darst.

Ill., graph. Darst.

It should be shown, that it is possible to insert radioactive isotopes of Yb and Y into some selected porphyrins. Besides, first informations about the biodistribution of Yb-169-por-phyrin-complexes should be obtained.Carrier added radioactive isotopes were used for the synthesis of the metal porphyrin complexes. The animal experiments were done with mamma carcinoma bearing mice. The activity of the organs was determined 5 and 24 h after i.v. injection in a well counter.Four Yb-169-porphyrin complexes and Y-90-porphyrin complexes could be synthesized in non-carrier-free form. This was verified by absorption spectra, TLC and HPLC. Depending on the complex, the average tumour/background ratios were between 2 and 20.The synthesized radioactive metal-porphyrin complexes showed a clear tumour-affinity which could be used for tumour scintigraphy or perhaps therapy if the synthesis is improved (goal: reduction of carrier, other radionuclides).

The erbium: YAG laser (wavelength 2940 nm; pulse duration 0.350 ms; pulse energy 0.1-1.7 J) allows vaporization of very thin skin layers without scarring and minimal lateral thermal injury due to an extremely short pulse duration. It permits exact ablation of relatively large areas of facial skin. We report our results with 216 patients following treatment for different facial lesions (facial wrinkles, acne scars, syringomas, and circumscribed sebaceous gland hyperplasia) using a new erbium: YAG laser system. Good-to-excellent cosmetic results were obtained in these patients. Our findings show that the erbium: YAG laser is an elegant and promising new method for the treatment of facial lesions.

Clinical investigations have been made in 70 patients to determine whether 169Yb-labelled metal ligand complexes accumulate in various tumors as was shown by previous animal experiments. The time course of these radiopharmaceuticals in tumors, the skeleton and the liver permitted a good to excellent tumor imaging in 61/70 cases. Even 2-5 h after intravenous injection of the radioactive compound, a meaningful diagnosis could be made in the majority of cases. A number of lesions were found for which no equivalent findings were available with other methods. They were therefore interpreted as metastases.

169Yb complexes with known biokinetics in tumour-bearing mice up to 48 h p.i. were injected into healthy mice to study the radionuclide biodistribution in various organs and tissues for 672 h after injection, in order to obtain reliable biokinetic data in an animal model, not affected by tumour-growth, as a basis for the calculation of biological half-life and dose distribution. The results demonstrated the existence of at least two components with different biological half-lives in the organs and tissues investigated. The effective half-lives of these components decreased with increasing stability of the complexes administered. The effective half-life of the fast component was a few hours and that of the slow one between about 200 and 800 h.

The absorption of the elements iodine, gadolinium and ytterbium in various dilutions was studied in relation to CT. Regression analysis and specific CT density measurements showed that absorption decreases from gadolinium to ytterbium and iodine. These results were confirmed by experiments using ten dogs. Boli of 0.5 molar gadolinium used for angio-CT without table movement showed the largest increase in density in the aorta and liver with an average of 190HU and 21HU respectively compared with iodine which gave 157HU and 12HU respectively. The animal experimental studies suggest that gadolinium and ytterbium are suitable contrast media for dynamic CT investigations.

It is well known that after application of radioactive complexes for tumour diagnosis or therapy, such as 67Ga-citrate or radiolanthanide complexes (167Tm- or 169Yb-nitrilotriacetate, -citrate, -alpha-hydroxyisobutyrate, 90Y-citrate, etc.) activity is accumulated not only in the tumour but also in other organs, above all liver and bone. This is the main obstacle to their medical use. Recently published results encouraged us to use ethylenediaminetetramethylene phosphonate (EDTMP) for the reduction of extratumoural liver activity. The results show that even small amounts of EDTMP (1-2 mg/kg BW) reduce the activity deposition in the liver by about one order of magnitude. EDTMP provoked elimination of activity from tumour, skeleton and other tissues but not to the same extent as from the liver. Tumor/liver activity ratios5 are achievable in this manner.

The complexon CaDTPA was injected into tumour-bearing mice in concentrations of 0.05, 0.1, 0.3, and 0.6 mole/l (pH:6) 30 min after the 169Yb-injection. 100 microliters of a 0.3 M CaDTPA solution were injected at different time points (simultaneously, 2, 5, 10, 20, 30, 40 and 50 min, 1, 1.25, 1.5, 2.5 and 10 h) after 169Yb-citrate injection. The animals were killed 24 h after radionuclide administration. A strong radioactivity decrease was observable 24 h p.i. not only in blood, liver, spleen, muscle and bone but also in the tumour if CaDTPA was administered within the first 2 h after ytterbium injection. Thereafter no change in radioactivity could be achieved by DTPA. A time phase in which the Yb could be eliminated from the tissues by means of DTPA (time intervals2 h) was distinguishable from a time phase in which it was not attainable for DTPA (time intervals5 h). This indicates that the incorporation of Yb into the cells is completed after 5 h and that the metals are intracellularly bound, probably to the lysosomes. Improvements of the scintigraphic tumour detection cannot be expected from the use of complexons.

Li[Me2Si(OtBu)(NtBu)] (1) reagiert mit YbI2 zum Ytterbium(II)alkoxysilylamid [Me2Si(OtBu(NtBu)]2Yb(THF)2 (2). Die analoge Reaktion von 1 mit SmI2 liefert das Samarium(III)derivat [Me2Si(OtBu)(NtBu)]2Sm(μ-I)2Li(THF)2 (3). Däruber hinaus wird die Darstellung von [Me2Si(O)tBu)(NtBu)] Nd (4) und [Me2Si(OtBu)(NtBu)]2Yb(μ-Cl)2Li(THF)2 (5) beschrieden. Die Molekülstrukturen von 4 und 5 wurden röntgenographisch bestimmt. Abstract: Li[Me2Si(OtBu)(NtBu)](1) reacts with YbI2 to give the ytterbium(II)alkoxysilylamide [Me2Si(OtBu)-(NtBu)]2Yb (THF)2 (2). The analogous reactio of 1 with SmI2 yields the samarium(III) derivative [Me2Si(OtBu)(NtBu)]2Sm(μ-I)2Li(THF)2 (3). Moreover, the preparation of [Me2Si(OtBu)(NtBu)]3Nd (4) and [Me2Si(OtBu)(NtBu)]2Yb(μ-Cl)2Li(THF)2 (5) is described. The molecular structures of 4 and 5 have been determined by X-ray crystallography. peerReviewed

In a group of patients with solitar kidney a radioisotope clearance was performed to determine exactly the renal functional status and to reduce the blind area of standard diagnostical parameters. In 41 percent of these patients a restriction of the glomerular or tubular value was found. In the same way the function-diminishing effect of hypertension on renal plasma flow and tubular-secretory function was determine. In the present study of dynamic radioisotope investigations in patients with solitar kidney could be verified.

A method for the simultaneous determination of the effective renal plasma flow and of the glomerular filtration rate with the help of 131J-o-iodohippuric acid and 169Yb-DTPA using a double isotopic technique is described. Apart from this the method serves for the establishment of the filtration fraction. 40 patients with different clinical pictures (glomerulonephritis, pyelonephritis, cystic kidneys, stenosis of the renal artery) were examined. The clearance values established by us were in the areas characteristic for the clinical pictures. Pathological conditions could be established which are not yet characterized by an increase of the fixa of the urine in the serum. By the determination of the filtration fraction differential-diagnostically important insights are afforded. The examination is methodically simply to be performed and is of little stress for the patient. Therefore it seems to be suitable for the routine examination.

Using quantitative sequential camera scintigraphy and simultaneous separated clearance determinations with 131-I-Hippuran and 169-Yb-EDTA renal function was measured applying a new surgical method which permits in-situ kidney perfusion and cooling in animals and patients. While mongrel dogs of 15 kg average weight (control group of N = 5) showed after 1 hour of normothermic ischaemia a postoperative delay of intrarenal transport of 131-I-Hippuran with reduction of 131-I-Hippuran and 169Yb-EDTA clearances, renal function returned to normal on the first postoperative day after 1-hour (N = 5) and 2-hour (N = 5) hypothermic ischaemia. In patients (N = 9) with hypothermic in-situ perfusion of between 40 and 92 min duration a transient postoperative delay of intrarenal 131-I-Hippuran transport and a reduction of the 131I-Hippuran clearance was observed which returned to almost normal 1 1/2 to 3 months after surgery. The results and the significance of the method discussed and are compared with clinical findings and with radiological and laboratory renal function studies.

This study discusses the clinical validity of 101 postural scintimyelograms as a screening method for cervical myelopathy. The RIHSA or Ytterbium isotope-examination are not an extra burden to the patient if the radiopharmacon is introduced into the dural sac following Queckenstedt's test. If there is a normal rise and fall of CSF pressure after bilateral jugular compression and postural scintimyelography is judged normal as well, a cervical subarachnoid obstruction may be excluded. If both examinations yield pathological results an obstructive process in the cervical spinal canal is made certain; and in cases of spondylotic myelopathy a positive contrast myelogrpahy may thus be superfluous. If the results of these two examinations are contradictory then further neuroradiolocal studies are indicated.

Some of the radiopharmaceuticals presently recommended for cisternoscintigraphy were compared, in experiments on animals, for their effects upon bioelectric activity. On relaxed cats, electroencephalography did not show any effects upon bioelectric activity for 198 Au and 169 Yb Ca DTPA. One test animal each of seven and six cats examined using 169 Yb DTPA and 131 J HSA showed changes in the electroencephalogram subsequent to suboccipital application.

Liquor-scintigraphic examinations were carried out with Yb 169-DTPA in two patients, who were offering - clinically as well as by pneumo-encephalographic findings - the picture of a cerebro-atrophic process. Especially the first case showed the typical course and symptoms of Alzheimer's disease. A "stasis" of the radionuclide, lasting for 48 hours, was manifesting liquor-scintigraphically herein, in the course of which there was - initially - a weak representation of the ventricles. However, the complete clinical picture of a communicating hydrocephalus did not show up. In the second case, an undisturbed liquor circulation and absorption, to a great extent topically and temporally undisturbed, were observed. The question arises whether Alzheimer's disease is manifesting together with such a disturbance of the liquor circulation, already described also by other workers. The second case makes clear that the liquor space scintigraphy cannot be used as only diagnostic method in all cerebro-atrophic processes.

The results obtained by scintillation scanning of the cervical CSF space at maximum ante- and retroflexion in 24 patients show that the method can be recommended for use in the case of cervical myelopathy when the polymorphous early symptoms appear and before myelography. Its use for follow-up examinations is also recommended. The detection of posture induced constriction of the lumen provides additional information and increases the sensitivity considerably because, particularly during retroflexion, minor inflammatory reactions lead to scintigraphically detectable reductions in the liquor space.