Initial clinical experience with a new pulsed dye laser device in angioplasty of limb ischemia and shunt fistula obstructions.

Selective plaque ablation with laser radiation at 405-530 nm in vitro has been reported. We investigated the possibilities of a new pulsed dye laser device for in vivo recanalization of arteries in ischemic lower limbs and stenoses/occlusions of arterio-venous hemodialysis shunt fistulae. A specially designed 9F or 7F multifiber catheter was used for treatment of 10 patients with lower limb artery obliterations and 11 patients with malfunctioning hemodialysis access fistulae (HAF). The recanalization technical success was 5/5 in the iliac arteries (IA), 4/5 in the superficial femoral arteries (SFA), and 11/11 in the HAF. Early re-occlusions occurred in one SFA and one IA, respectively, caused by very bad run-off. There was one clinically insignificant SFA perforation. Additional balloon angioplasty was considered necessary in 10/16 lesions. Mean ankle-arm index increased from 0.68 to 0.97. With two exceptions all HAF patients were re-integrated in the dialysis program. Pulsed dye laser angioplasty promises to be an effective and fast method for plaque ablation/debulking. The first clinical experience confirms previous in vitro results. In particular laser recanalization may become the method of choice for treatment of rigid HAF obstructions and it seems to be superior to vascular surgery or balloon angioplasty alone.     

Cytostatica- und Röntgenstrahleneffekte im Nucleinsäurestoffwechsel von soliden,malignen Tumoren in vitro

Zusammenfassung Unter in vitro-Bedingungen wird der Einbau von [¹⁴C] Thymidin und-Desoxyuridin in die DNS, von [¹⁴C] Uridin,-Cytidin,-Uracil,-Adenin,-Hypoxanthin,-Glycin,-Formiat und-Orotsäure in die RNS und von [¹⁴C] Leucin in die Proteine von soliden, malignen Tumoren gemessen.Bei Applikation von Cytostatica werden die Einbauraten dieser [¹⁴C] markierten Nucleinsäure-und Proteinbausteine in die Zellen verschiedener Tumoren unterschiedlich gehemmt. Die eingesetzten Cytostatica sind a) die Antimetabolite 5-Fluor-uracil, Methotrexat und 6-Mercaptopurin=Purinethol, b) die alkylierenden Cytostatica Trenimon und Mitomen, c) das Actinomycin-D und d) Hormone wie das Cortisolderivat Urbason und die Geschlechtshormone Oestriol und Testosteron.Röntgenbestrahlung (1000 und 2000 R) bewirkt unter den in vitro-Bedingungen keine echte Hemmung im Nucleinsäurestoffwechsel der Tumoren.Zielsetzung dieser Untersuchungen ist, aus den Einbauraten unter Applikation der angeführten Cytostatica die Sensibilität der malignen Tumoren gegenüber den wachstumshemmenden Substanzen testen zu können, um dementsprechend eine gezielte cytostatische Nachbehandlung anscheinend radikal-operierter Carcinompatienten durchführen zu können.

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Effects of cytostatics- and X-ray on nucleic acid metabolism of solid neoplasms in vitro

Summary A study has been performed to measure the incorporation rate of [¹⁴C] thymidine-and deoxyuridine into DNA, of [¹⁴C] uridine,-cytidine,-uracil,-adenine,-hypoxanthine,-glycine,-formiate and orotic acid into RNA, and of [¹⁴C] leucine into protein of solid neoplasms.If cytostatics were applied, the uptake of [¹⁴C] labeled nucleic acid-and protein precursors into the cells of different tumors are inhibited differently. The employed cytostatics are a) the antimetabolites 5-fluor-uracil, methotrexate and 6-mercaptopurine=purinethol, b) the alkylating cytostatics trenimon and mitomen, c) actinomycin-D and d) hormones like the cortisol-derivative urbason and the sexual hormones oestriol and testosterone.X-ray radiation (1000 and 2000 R) does not cause in this in vitro system a genuine inhibition of the nucleic acid metabolism of tumors. The aim of this study was to establish a test system to measure the sensibility of neoplasms which have been treated in vitro with the above cytostatics in order to allow a special therapy of apparently tumorectomized patients.

     

Antilymphocytic antibodies and marrow transplantation. VIII. Recipient conditioning with Clq-affine monoclonal anti-pan T antibodies prevents GVHD in homozygous fully mismatched mice

An approach to suppressing secondary disease with antibodies was studied that differed from conventional antibody treatment of donor marrow in vitro. It consisted of the selection of anti-Thy-1 antibodies with high affinity for Clq, the first subunit of the complement cascade, and a single injection of such antibodies into prospective irradiated marrow recipients. Monoclonal mouse IgM and rat IgG 2c antibodies of high titers in complement-dependent test systems but with low affinity for Clq caused little immunosuppression. Monoclonal rat IgG2b or mouse IgG2a anti-Thy-1 antibodies with high affinity for Clq prevented acute and chronic mortality of graft-v-host disease (GVHD), however, when injected in irradiated CBA or AKR mice prior to C57BL/6 spleen and/or bone marrow cell transfusion. This treatment simultaneously suppressed residual host-v-graft reactivity of the irradiated mice, so that permanent hematopoietic engraftment ensued even at 5 or 6 Gy. Full chimerism and specific tolerance were obtained. Primary immune response to SRBC was clearly depressed in the chimeras; secondary immune response was not. Clearance of T cell antibody activity (greater than 6 days), timing, and dose of injected antibody, as well as other modalities of the conditioning treatment that may have contributed to the remarkable immunosuppression, are discussed.     

Effects of the initial temperature of acrylic bone cement liquid monomer on the properties of the stem-cement interface and cement polymerization

It has been shown that preheating the femoral stem prior to insertion minimizes interfacial porosity at the stem-cement interface. In this study, the effects of methylmethacrylate monomer temperature prior to mixing on the properties of stem-cement interface and cement polymerization were evaluated for 4 degrees C, room temperature, and 37 degrees C using a test model and cementing techniques that simulated a clinical situation. The nature and extent of interfacial porosity of stem-cement interface was quantified, the static shear strength of the stem-cement interface determined, and the time and temperature of polymerization at the cement-bone interface were measured. Compared to RT monomer, preheating monomer to 37 degrees C produced higher polymerization temperatures and greater initial interfacial shear strength with an unchanged amount of interfacial porosity. Precooling monomer to 4 degrees C produced lower polymerization temperatures and decreased initial interfacial shear strength, with the amount of interfacial porosity unchanged compared to the RT group. Although clinical techniques of preheating or precooling bone cement have some effects on the properties of the stem-cement interface and cement polymerization, they do not appear to enhance implant fixation.