Effect of ASTA Z 7557 (INN mafosfamide) a precursor of 4-hydroxy-cyclophosphamide on human T-lymphocytes' Fc-receptors and immunoregulatory functions

The precursor ASTA Z 7557 of the in vivo active metabolite 4-hydroxy-cyclophosphamide (4OH-Cy) of cyclophosphamide (Cy) was tested for selective effects on human T-lymphocytes' Fc gamma-receptor expression and certain immunoregulatory functions. It has been found that ASTA Z 7557 does not alter the expression of Fc gamma-F- or Fc gamma-I-receptors on the T-cell membrane nor does it exhibit differential toxicity for either T-cell subpopulation. PWM-induced B-cell proliferation is inhibited by ASTA Z 7557, whereas B-cells' Ig-synthesis as well as ConA-driven T-cell proliferation is only blocked with higher doses of the reagent. Final concentrations above 1 microgram/ml may therefore abrogate ConA-induction of suppressor T-lymphocytes. Already ConA-activated suppressor cells of PWM-driven B-cell cultures, however, are not inhibited even with high doses of ASTA Z 7557.

Eye-safety requirements for Nd:YAG laser application in gastroenterology, urology, and neurosurgery

The preconditions relating to radiation safety for application of the Nd:YAG laser in the various fields of open and endoscopic surgery are studied. Potential eye hazards of clinical personnel using a Nd:YAG laser photocoagulator in surgical procedures are investigated and methods of eye protection are discussed. The amount of exposure of the eye to radiation back-scattered from stomach and bladder tissue, as can occur in clinical practice, has been determined for several commercially available rigid cystoscopes and flexible gastroscopes. In addition, the amount of back-scatter from brain and liver tissue has been established under the usual surgical working conditions. The International Electrotechnical Commission (IEC) and the American National Standard Institute (ANSI) provisions relating to laser safety are briefly explained in relation to the use of the Nd:YAG laser. The results of experimental investigations are compared with the maximum permissible exposure (MPE) limiting values as per the IEC and ANSI drafts. The precautions necessary for safe application of the Nd:YAG laser in the various medical spheres are described.

Interception of lymphatic drainage by Nd: YAG laser irradiation in rat urinary bladder

Lymphatic drainage can be demonstrated by colloidal indian ink injection. A small intramural indian ink spot in the bladder dome is separated from the rest of the rat urinary bladder by encircling transmural Neodymium-YAG (Nd:YAG) laser irradiation. In untreated animals there is an ink flow via the lymphatic vessels to the regional lymph nodes within several hours. In treated animals, after laser irradiation, the indian ink remains in the bladder dome and a penetration of the irradiated area cannot be found by macroscopic and histologic examination. Indian ink will be found in the regional lymph nodes after the ninth day of absorption of the coagulation necrosis and recanalisation of the intercepted lymphatics. Evidence for the interception of the lymphatic drainage is demonstrated by the distinctly delayed ink flow and the injected ink's remaining in the irradiated area. From this, we conclude that Nd:YAG laser irradiation is especially suitable for tumor coagulation, since simultaneous interception of lymphatic drainage will inhibit the spreading of tumor cells.

Percutaneous trigeminal thermorhizotomy in treatment of malignant facial pain

Fifty-eight patients suffering from intractable pain in the trigeminal distribution due to neoplasms of the intracranial or facial regions underwent controlled percutaneous coagulation of the Gasserian ganglion (trigeminal thermorhizotomy). Of them, 35 were evaluated at varying time intervals from the intervention (mean: 7 months). While pain was completely relieved in 71 per cent of cases at discharge, the follow-up examination was consistent with 49 per cent of analgesias. The rationale of percutaneous thermocoagulation in malignant facial pain is given and the pertinent literature summarized.

[Interstitial radiotherapy using I-125 seeds in brain neoplasms of slow development]

The opportunity of stereotactic biopsy for the histological diagnosis of brain tumors, the radiobiologic bases, clinical implications and technical possibilities of interstitial radiation therapy are discussed. The results of 9 cases, out of 14 treated to-date over 20 months, with a minimum follow-up of 4 months, are presented.

Leptomeningeal angiomatosis and aplasia congenita of the scalp. Case report

This 9-year-old boy had two circular areas of aplasia congenita of the scalp in the territory of the first division of the trigeminal nerve and an ipsilateral parieto-occipital leptomeningeal capillary venous angioma. He had an associated giant aneurysm of the distal posterior cerebral artery on the same side as the vascular malformation. The patient had a long history of seizures and presented with intracerebral bleeding. This case may be considered as a variant of Sturge-Weber syndrome. Further observations must be added to consider this entity as a separate neurocutaneous disease.

[Destruction of ureteral tumors with the neodymium-YAG laser. A new, organ-preserving surgical procedure]

Only the neodymium-YAG laser is suitable for destroying tumors endoscopically, because it shows a very high transmission through water and a slight absorption in the tissue. It means scattering becomes important and leads to a homogeneous and uniform distribution of the radiation in the tissue producing a deep thermal effect. An examination of a section through a bladder wall under light microscope after neodymium-YAG laser irradiation shows a layered, sharply delimited coagulation necrosis that extends to all of the bladder wall layers and reaches the outermost zones. In this way it is possible to destroy not only the exophytic part of a tumor but also the tumor base in the tissue. Since 1976 we destroyed more than 4000 bladder tumors by laser application. For tumors on the ureter or kidney pelvis a special endoscope, described by Perez-Castro Ellendt and modified by us, can be used, if it is not possible to perform a conventional operation. It is reported about four cases of distal ureter tumors (GI-II) in patients who had refused an operation for removing the tumor bearing ureter segments. Now, for more than one and half a year all patients are free of tumors and the irradiated ureters show a good function. This novel procedure is not for routine, but for high risk patients or patients, who refuse an open operation.

Transurethral laser coagulation for treatment of urinary bladder tumors

Owing to the biophysical properties involved, the Nd:YAG laser is most suited for coagulation of even inhomogeneous tissue. We determined the optimal laser parameters for therapy of urinary bladder tumors. Deep homogeneous necroses can be obtained without perforation risk of the bladder wall, and the procedure does not cause dangerous damage to the intestinal loops. We have studied animal experiments by close examination and systematic inquiry, and thus we were able to determine sufficient laser parameters in dependence on tissue thickness. Clinical studies verified these results for living human tissue. After some years of clinical use of the Nd:YAG laser we can make the first statistical statements.

[Fc gamma receptor-bearing T lymphocytes in systemic lupus erythematosus in relation to disease activity and treatment]

In peripheral blood of SLE-patients fluctuating patterns of Fc-gamma-receptor bearing T-lymphocytes have been observed, when long term monitoring has been performed. No influence of disease activity and corticoid treatment on number of Fc-gamma-receptor bearing lymphocytes was seen.

Stereotaxic rostral mesencephalotomy in treatment of malignant faciothoracobrachial pain syndromes. A survey of 14 treated patients

Stereotaxic rostral mesencephalotomy was performed 19 times in 14 patients suffering from intractable pain syndromes due to malignant diseases. The satisfying results in terms of pain relief during a necessarily short follow-up period (mean 4.9 months) are outlined. Undesired side effects were mainly confined to oculomotor disorders, which partly subsided over the months following the operation. Some technical aspects of the procedure and the pertinent literature are briefly discussed.

CT scan and metrizamide CT cisternography in arachnoid cysts of the middle cranial fossa: classification and pathophysiological aspects

Thirty-one cases of arachnoid cysts of the middle cranial fossa were investigated by CT scan, 7 of them undergoing additional metrizamide CT cisternography. In this paper we analyze and correlate the different findings from these two examinations and propose a classification of arachnoid cysts of the middle cranial fossa into three basic types. Pathophysiological and surgical implications are discussed.

[The effect of basic therapeutic procedures on the immunoregulatory T-cell apparatus in patients with chronic polyarthritis]

Five by five patients with rheumatoid arthritis were treated with gold salts, D-penicillamine and cyclophosphamide. The T-lymphocyte subpopulations were measured. In patients, treated with gold salts or D-penicillamine, we did not find alterations of the number of TG- and TM-lymphocytes. The daily treatment with 100 mg cyclophosphamide will result in a significant reduction of TG-lymphocytes.

Hamartomas of the tuber cinereum and precocious puberty

5 cases of true precocious puberty (TPP) of cerebral origin are presented. The clinical and radiological features and the protracted follow-up allow, also in view of the literature, a highly presumptive diagnosis of a hamartoma of the tuber cinereum. The high incidence of these lesions in cases of TPP is emphasized, together with the importance of early neuroradiological assessment.

Various effects of the CO2-, the neodymium-YAG-, and the argon-laser irradiation on bladder tissue

Application of lasers as cutting or coagulation instruments is based on the conversion of light energy into heat in the irradiated tissue. The extent and degree of the thermal action depends on the beam geometry and the energy of the incident light, as well as on the optic and thermal properties of this tissue. The extinction behavior in the tissue differs for the various laser systems employed in medicine. A comparison of the effects on bladder tissue of rats and rabbits is made with Neodymium-YAG laser and the argon and CO2 lasers to demonstrate the advantages of the Neodymium-YAG laser, especially for the therapeutic irradiation of bladder tumors.

Natural and antibody-dependent cellular cytotoxicity in tumour-adherent T lymphocytes: expression of Fc receptors and of a human T-subgroup-specific antigen

Adherence of human lymphocytes to allogeneic tumour cell monolayers was found to depend on the presence of monocytes. Adherent lymphocytes could be separated from tumour cells by treatment with lidocaine followed by nylon wool passage. Tumour-adherent cells (70% E-RFC, 45% Fc gamma-R, 23% Fc mu-R, 5% monocytes) exhibited enriched natural killer (NK) activity not only against the tumour cell line used for isolation but also against seven other targets. When T cells were isolated subsequently as E-rosettes by density gradient centrifugation through Percoll, the enrichment in cytotoxicity was even more pronounced. Tumour-adherent T cells were severalfold enriched in both NK and antibody-dependent cell-mediated cytotoxicity (ADCC) activity. However, this enrichment was not paralleled by a concomitant increase in the number of T gamma cells (tumour-adherent T cells: 17% T gamma, 40% T mu ; tumour-nonadherent T cells: 12% T gamma, 60% T mu). Marked differences could be observed by staining with a monoclonal antibody that was raised against human leukaemic T gamma cells of high NK and ADCC activity. This antibody (T 8-11) stained 60% of tumour-adherent T cells, 20% of nonadherent T cells and 29% of T-cell controls. These results indicate that the spontaneous cytotoxic activity of human T cells resides within a small population, most of which are characterized by a specific surface antigen but not by conventional Fc gamma receptors.

Endoscopic Neodymium-YAG laser application for destroying bladder tumors

302 bladder tumors to a size of a thumb tip were treated with a Nd: YAG laser. 196 large bladder tumors were removed by transurethral resection combined with laser irradiation 1 week later. In all cases tumors were classified as pTA to pT3a, No, Mo tumors. 8 weeks after treatment we found local recurrences in 9% using the rigid laser endoscopes. On the contrary, the local recurrence was 2.1% using laser endoscope with modified Albarran insert. In proven cases the Nd:YAG laser application is an effective and careful procedure to destroy bladder tumors.

Efficient separation of human T lymphocytes from venous blood using PVP-coated colloidal silica particles (percoll)

In a comparative study, human peripheral T lymphocytes were separated as E rosettes by density centrifugation through various gradient media. Sheep red blood cells (SRBC) were removed by dissociation of the E rosettes at 37 degrees C with subsequent centrifugation on a similar density gradient prewarmed to 37 degrees C. In particular, gradients made of Ficoll Urovison were compared with Percoll gradients with regard to both separation steps. Using Percoll gradients, a maximal T cell recovery of 75% was obtained, whereas Ficoll separation yielded only 46%. T lymphocytes separated with Percoll exhibited equal viability compared to Ficoll isolated cells and consisted of 98% EAET-RFC. No inhibition of cellular function by Percoll treatment was detected, whereas Ficoll treatment led to an impaired mitogenic response. An inherent mitogenicity of Percoll was not observed. The method described results in considerably shortened centrifugation times due to the low viscosity of the Percoll medium and simultaneously seems to be less harmful to the rather fragile rosettes. Reproducibility was found to depend on careful control of density and osmolarity of the Percoll medium.