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Experimental treatment of eyelashes with high-frequency radio wave electrosurgery.

Apart from mechanical epilation, which is a nuisance to both the patient and the ophthalmologist, standard techniques for removing unwanted eyelashes, such as electrosurgery (Hyfrecator) and cryosurgery, may cause eyelid tissue damage and other complications. Refinements in electrosurgical techniques have enabled production of a machine that can provide high-frequency radio waves with a modification of the waveform to produce a blended cut-coagulation effect (Ellman Surgitron). Treatment of hairs in fresh calf skin with the Ellman Surgitron resulted in destruction of the germinal cells of the hair follicle, with only a small amount of tissue change lateral to the track of the electrode; the Hyfrecator caused total sloughing of the epithelial cells, with marked superficial tissue changes due to heat spread. In six eyelids of six patients undergoing eyelid excision the Ellman Surgitron was effective in causing destruction of the germinal cells of the hair follicle, with very little lateral heat spread in the tissues or destruction of the skin epithelial cells. As well, there was no tissue damage anywhere near the conjunctival surface.

Animals↗

["Radio-medical Advice Service"--14 years of overseas medical advice].

From 1980 to 1993, the Danish Radio Medical Advice Service (RMAS) had 1136 contacts from overseas Danish merchant ships and 213 contacts from Danish territorial waters. The distribution of the diagnoses in the overseas contacts were: Diseases in the digestive and genitourinary system 30%, traumatic lesions 23%, infectious diseases 14%, diseases in the cardiovascular and respiratory system 9%. The only trend over the years was a significant (p = 0.01) decrease in psychiatric diagnoses. Evacuation was recommended in 53% and medicine was prescribed in 61% of the contacts. The medical speciality for doctors participating in RMAS should be general surgery or orthopaedic surgery but access to advice from all other medical specialities should be available. Experience as a naval medical officers would be beneficial. The education of the officers on the ships should include intravenous infusion. The communication should be by telephone and television would be an advantage.

Counseling↗

Evaluating the program effects of a radio drama about AIDS in Zambia.

This study describes an approach to the analysis of data that is designed to isolate program effects for evaluations and applies that approach to a program in Zambia designed to disseminate AIDS information. Evidence is considered that a radio drama broadcast for nine months had an impact on knowledge and behavior related to AIDS among Bemba speakers in northern Zambia. Using results from large sample surveys (1,600 men and women), conducted before and after the drama was broadcast, the analyses compare changes in knowledge and behavior in those most likely and least likely to have listened to the broadcast. While the population as a whole had improved its knowledge substantially, and some people reported having reduced risky behavior, attributing these changes to the program itself was not possible.

Acquired Immunodeficiency Syndrome↗

Percutaneous ablation of malignant liver tumor in rabbits using low radio frequency energy.

Radio frequency (RF) current has been used successfully to ablate normal human tissue. To further investigate the clinical application of this modality in tumors we studied the potential of using RF percutaneously to destroy experimental liver tumors. Thirty five outbred albino rabbits underwent liver VX2 tumor direct-implantation during open surgery. After 21 days ultrasonography was performed revealing tumor presence and size. A shielded RF needle was designed so that it could be inserted percutaneously through an introducing needle, and an electrical insulation shield covering the RF needle could be retracted to control the length of the exposed RF needle inside the tissue. Twenty two days after tumor implantation RF was applied via the aforementioned needle using a ZoMed International RF generator. In one group of rabbits the procedure was performed under direct vision during open surgery and on the other group treatment was applied percutaneously, guiding the needle by tumor palpation. Rabbits were killed 3 days later and pathology revealed 4 to 25 mm intratumoral RF induced lesions. A direct relation was found between lesion size, power and duration of RF application (At 7.5 W, r = 0.48, p = 0.032). Based on our preliminary results we may conclude that RF may have clinical application in the near future for percutaneous local tumor control in parenchymal organs.

Animals↗

VACTERL-hydrocephaly, DK-phocomelia, and cerebro-cardio-radio-reno-rectal community.

Phenotypic manifestations of the autosomal recessive form of VACTERL-hydrocephaly syndrome (David-O'Callaghan syndrome) and the X-linked recessive form (Hunter-MacMurray) syndrome are almost identical. The absence of cardiovascular malformations in cases with undoubtedly X-linked inheritance may be the only exception. The comparison of patients with David-O'Callaghan syndrome and nonclassified sporadic cases of VACTERL-hydrocephaly showed two marked differences. First, radial involvement (usually bilateral) occurred in all familial but only in 22 of 36 sporadic cases. Therefore, radial noninvolvement may be evidence against a genetic origin of the complex in a sporadic case. Second, predominantly severe forms of cardiovascular malformations were found in cases of David-O'Callaghan syndrome, whereas in sporadic cases almost all cardiovascular malformations were simple defects with minimal, if any, hemodynamic disturbances. The similarity of the spectrum and frequency of main manifestations of David-O'Callaghan and von Voss-Cherstvoy syndromes allows us to think that both of these syndromes actually might be 2 forms of one genetic entity. There are some syndromes with abnormalities of the brain (different for each syndrome) sharing the same limb defects (mainly preaxial), congenital heart defects, abnormalities of kidneys, and anal atresia/ectopia. Baller-Gerold syndrome, Steinfeld syndrome, XK-aprosencephaly, and DK-phocomelia (von Voss-Cherstvoy) syndrome as well as Mendelian forms of VACTERL-hydrocephaly syndromes fit into this "cerebro-cardio-radio-reno-rectal community."

Abnormalities, Multiple↗

Interferon-gamma (IFN-gamma) as a potential radio- and chemo-protectant.

Interferons (IFN) have had increasing clinical usage in the treatment of a variety of disorders, at times being used in combination with chemo- or radiotherapy. However, interferons may have inhibitory effects on hematopoietic stem cell proliferation and the effects of this cytokine's use on long-term hematologic function have not been studied. We performed the competitive repopulation assay in the murine system, using cells exposed to irradiation or single-dose chemotherapy with or without concomitant IFN-gamma use. IFN-gamma alone had no deleterious effects on hematopoietic stem cell productivity. We measured the repopulating ability of exhaustible multilineage precursors that were present at early stages of marrow repopulation after competitive repopulation (30 days). These progenitors were minimally impacted by cyclophosphamide (CTX) with or without IFN-gamma. Irradiation (XRT) and CTX alone produced significant repopulating defects in the most primitive hematopoietic stem cell, PHSC. Addition of IFN to either treatment regimen resulted in protection of PHSC, with improved repopulating ability, although the levels of donor marrow reached control levels only when CTX and IFN were used together. The results of multiple use of IFN with chemotherapy must be studied further, but IFN may offer hematologic radio- and chemoprotection, in addition to its antitumor properties in clinical protocols for treatment of cancers.

Animals↗

Radio-induced modulation of transforming growth factor beta1 sensitivity in a p53 wild-type human colorectal-cancer cell line.

Unlike normal intestinal cells, colorectal-carcinoma cell lines are usually not responsive to transforming growth factor beta1. The cyclin-dependent kinase inhibitor p21 that is induced by X irradiation in cells expressing normal p53 can also be induced by TGF-beta1 by a p53-independent pathway. We have investigated possible interactions between ionizing radiation and TGF-beta1, using a panel of 8 human colorectal-cancer cell lines varying in p53 status and sensitivity to the cyto-inhibitory effect of TGF-beta1. Heterogeneity in the radiosensitivity of these cell lines was observed, with SF2 (surviving fraction after irradiation with 2 Gy) ranging from 0.19 to 0.82. Radioresistance (high SF2 values) was in general associated with abnormal expression of p53. An effect of TGF-beta1 treatment on radiosensitivity was observed with one cell line only (LS513), and manifested by enhancement of the cytotoxic effect of radiation. In an experiment with fractionated irradiation during continuous exposure to TGF-beta1, there was no change in the intrinsic radiosensitivity of LS513 cells, though irradiated cells treated with TGF-beta1 were more sensitive to the first radiation dose. Irradiated LS513 colorectal-cancer and Mv-1-Lu epithelial cells were significantly more sensitive to TGF-beta1 than were unirradiated controls, whereas no change was observed in the TGF-beta1 sensitivity of irradiated LS1034 cells. Radio-induced modulation of TGF-beta1 sensitivity was transitory and declined before the decline to baseline level of p21 mRNA expression. On the basis of these results, we postulate that radiation-induced sensitization to TGF-beta1 occurs in TGF-beta1-sensitive cells expressing wild-type p53.

Cell Survival↗

Experimental studies on the role of antibody fragments in cancer radio-immunotherapy: Influence of radiation dose and dose rate on toxicity and anti-tumor efficacy.

Whereas bivalent fragments have been widely used for radio-immunotherapy, no systematic study has been published on the therapeutic performance of monovalent conjugates in vivo. The aim of our study was, therefore, to determine the therapeutic performance of (131)I-labeled Fab as compared to bivalent conjugates and to analyze factors that influence dose-limiting organ toxicity and anti-tumor efficacy. The maximum tolerated doses (MTDs) and dose-limiting organ toxicities of the (131)I-labeled anti-CEA antibody MN-14 [IgG, F(ab')2 and Fab] were determined in nude mice bearing s.c. human colon cancer xenografts. Mice were treated with or without bone marrow transplantation (BMT) or inhibition of the renal accretion of antibody fragments by D-lysine or combinations thereof. Toxicity and tumor growth were monitored. Radiation dosimetry was calculated from biodistribution data. With all 3 (131)I-labeled immunoconjugates [IgG, F(ab')2 and Fab], the red marrow was the only dose-limiting organ; MTDs were 260 microCi for IgG, 1,200 microCi for F(ab')2 and 3 mCi for Fab, corresponding to blood doses of 17 Gy, 9 Gy and 4 Gy, respectively. However, initial dose rates were 10 times higher with Fab as compared to IgG and 3 times higher as compared to F(ab')2. The MTD of all 3 immunoconjugates was increased by BMT by approximately 30%. In accordance with renal doses below 10 Gy, no signs of nephrotoxicity were observed. Despite lower absorbed tumor doses, at equitoxic dosing, Fab fragments were more effective at controlling tumor growth than the respective bivalent fragment or IgG, probably due to higher intratumoral dose rates. Our data indicate that the improved anti-tumor effectiveness of antibody fragments as compared to IgG and the higher myelotoxicity at comparably lower red marrow doses are most likely due to the higher initial dose rates observed with antibody fragments.

Animals↗

Anti-oxidant vitamins reduce normal tissue toxicity induced by radio-immunotherapy.

Our purpose was to determine whether the administration of anti-oxidant vitamins could reduce dose-limiting toxicity from radio-immunotherapy (RAIT) and thereby allow higher escalation of RAIT doses. Lipophilic vitamins A and E were administered i.p. and hydrophilic vitamin C was administered i.m. for 14 days (3 days pre-RAIT through 11 days post-RAIT) alone or with bone marrow transplantation (BMT) to either BALB/c mice for toxicity studies or to nude mice bearing s.c. GW-39 human colonic cancer xenografts for therapy studies. The maximal tolerated dose (MTD) of RAIT ((131)I-MN14 anti-CEA IgG) that results in no lethality was determined for mice that did not receive vitamins or BMT and those that did receive one or both interventions. Body weight, peripheral white blood cell (pWBC) and platelet (PLT) counts and tumor growth were also measured. Administration of vitamins (equivalent of 3.5 IU/day vitamin A, 0.107 IU/day vitamin E and 4.0 mg/day ascorbic acid) to mice along with BMT increased the MTD by 42% and reduced body weight loss associated with RAIT. Vitamins also reduced the magnitude of RAIT-induced myelosuppression. As early as day 7 after RAIT, vitamins increased WBC counts following both a 400 microCi and a 500 microCi dose. On day 14 after the 400 microCi dose of RAIT (day 7 post-BMT), the additive effect of BMT and vitamin could be detected. Tumor growth was not adversely affected by vitamin administration.

Animals↗

A critical investigation of the effects of the radio frequency potential on the trapping of externally injected ions in ion trap mass spectrometry.

The sensitivity of all ion trap mass spectrometry (ITMS) methods is dependent on the trapping efficiency of the instrument. For ITMS instruments utilizing external ion sources, such as laser desorption, trapping efficiency is known to depend on the phase and amplitude of the radio frequency (RF) potential applied to the ring electrode at the time of ion introduction. It is remarkable that, in a considerable body of literature, no consensus exists regarding the effects of these parameters on the efficacy of trapping externally generated ions. In this paper, a summary of the literature is presented in order to highlight significant discrepancies. New laser desorption ion trap mass spectrometry (LD-ITMS) data are also presented, from which conclusions are drawn in our effort to clarify some of the confusion. Copyright 1999 John Wiley & Sons, Ltd.

Journal Article↗

Transcatheter retrograde radio-frequency perforation of the pulmonic valve in pulmonary atresia with intact ventricular septum, using a 2 French catheter.

A neonate with pulmonary atresia with intact ventricular septum (PA/IVS) underwent successful retrograde transcatheter perforation of the pulmonary valve, using a 2 Fr radio-frequency catheter with subsequent anterograde balloon dilation of the valve. Due to persistent hypoxemia, the neonate underwent placement of a 4-mm modified Blalock-Taussig shunt. Transcatheter retrograde transductal perforation of the pulmonic valve in PA/IVS is feasible and may be a potential alternative to anterograde perforation.

Cardiac Catheterization↗

Simultaneous analysis of radio-induced membrane alteration and cell viability by flow cytometry.

BACKGROUND: Modifications of intracellular transfer, resulting from a loss of membrane integrity may contribute toward setting the cell onto the pathway of apoptosis. METHODS: We have developed an original technique of measuring simultaneously, with flow cytometry, changes in membrane fluidity and cell death status. Our aim was to assess the extent to which radio-induced cell death and membrane alterations are linked. Investigations were performed on lymphocytes 24 h after whole human blood gamma-irradiation. RESULTS: Our results confirmed the expected increase in the percentage of apoptotic cells as a function of dose, but revealed that the percentage of necrotic cells appeared stable after irradiation. At the same time, the fluorescence anisotropy of the living lymphocyte subpopulation decreased significantly and dose dependently as measured 24 h post-irradiation. With TMA-DPH, the anisotropy index of apoptotic lymphocytes was always lower than that of the viable lymphocyte subpopulation. On the other hand, 1,6-diphenyl-1,3,5-hexatriene (DPH) anisotropy was similar in apoptotic and viable cells after irradiation. These findings suggest that apoptotic lymphocytes are characterised by a membrane fluidization that mainly occurs on the cell membrane surface. CONCLUSION: Our study made technical advances in using cytometric fluorescence anisotropy measurement as an early biological indicator of apoptosis after cellular exposure to ionising radiation.

Apoptosis↗

New simplified radio-opaque injection technique for visualization of rat arteries.

We have developed a new and simplified injection technique based on a mixture of latex and lead oxide. This injection technique is unique in its possession of both color and radio-opacity. We have developed and refined this methodology in rats, and have demonstrated it to possess superior qualities of injectability. Depiction of small vessels is highly detailed both radiographically and grossly.

Angiography↗

Determination of IgE antibodies to the benzylpenicilloyl determinant: a comparison of the sensitivity and specificity of three radio allergo sorbent test methods.

The quantitation of in vitro IgE antibodies to the benzylpenicilloyl determinant (BPO) is a useful tool for evaluating suspected penicillin allergic subjects. Although many different methods have been employed, few studies have compared their diagnostic specificity and sensitivity. In this study, the sensitivity and specificity of three different radio allergo sorbent test (RAST) methods for quantitating specific IgE antibodies to the BPO determinant were compared. Thirty positive control sera (serum samples from penicillin allergic subjects with a positive clinical history and a positive penicillin skin test) and 30 negative control sera (sera from subjects with no history of penicillin allergy and negative skin tests) were tested for BPO-specific IgE antibodies by RAST using three different conjugates coupled to the solid phase: benzylpenicillin conjugated to polylysine (BPO-PLL), benzylpenicillin conjugated to human serum albumin (BPO-HSA), and benzylpenicillin conjugated to an aminospacer (BPO-SP). Receiver operator control curves (ROC analysis) were carried out by determining different cut-off points between positive and negative values. Contingence tables were constructed and sensitivity, specificity, negative predictive values (PV-), and positive predictive values (PV+) were calculated. Pearson correlation coefficients (r) and intraclass correlation coefficients (ICC) were determined and the differences between methods were compared by chi 2 analysis. Analysis of the areas defined by the ROC curves showed statistical differences among the three methods. When cut-off points for optimal sensitivity and specificity were chosen, the BPO-HSA assay was less sensitive and less specific and had a lower PV- and PV+ than the BPO-PLL and BPO-SP assays. Assessment of r and ICC indicated that the correlation was very high, but the concordance between the PLL and SP methods was higher than between the PLL and HSA or SP and HSA methods. We conclude that for quantitating IgE antibodies by RAST to the BPO determinant, BPO-SP or BPO-PLL conjugates offer advantages in sensitivity and specificity compared with BPO-HSA. These results support and extend previous in vitro studies by our group and highlight the importance of the carrier for RAST assays.

Adult↗

Humero-radio-ulnar synostosis: a new case and review.

We report on a patient with humero-radio-ulnar synostosis and upper limb oligoectrosyndactyly. All cases have been sporadic including discordance in monozygotic twins, and similar findings have occurred in thalidomide embryopathy. Further observations of similarly affected patients are needed to elucidate the nature of this upper limb defect and its cause.

Abnormalities, Multiple↗