Neutrophil Myeloperoxidase Destruction by Ultraviolet Irradiation

Author(s):  
J. Hanker ◽  
B. Giammara ◽  
G. Strauss

Only a fraction of the UV radiation emitted by the sun reaches the earth; most of the UVB (290-320nm) is eliminated by stratospheric ozone. There is increasing concern, however, that man-made chemicals are damaging this ozone layer. Although the effects of UV on DNA or as a carcinogen are widely known, preleukemia and acute myeloid leukemia (AML) have only rarely been reported in psoriasis patients treated with 8-methoxypsoralen and UV (PUVA). It was therefore of interest to study the effects of UV on the myeloperoxidase (MP) activity of human neutrophils. The peroxidase activity of enriched leukocyte preparations on coverslips was shown cytochemically with a diaminobenzidine medium and cupric nitrate intensification.Control samples (Figs. 1,4,5) of human bloods that were not specifically exposed to UV radiation or light except during routine handling were compared with samples which had been exposed in one of several different ways. One preparation (Fig. 2) was from a psoriasis patient who had received whole-body UVB phototherapy repeatedly.

Horizons ◽  
2021 ◽  
Vol 48 (1) ◽  
pp. 172-194
Author(s):  
Christopher Pramuk

In March 1943, having narrowly escaped Europe three years earlier, Abraham Joshua Heschel published “The Meaning of This War,” his first essay in an American publication. The essay shows, quite remarkably, his full command of literary English. It also shows, as biographer Edward Kaplan remarks, that Heschel “had found his militant voice.” “Emblazoned over the gates of the world in which we live,” the essay begins, “is the escutcheon of the demons. The mark of Cain in the face of man has come to overshadow the likeness of God. There have never been so much guilt and distress, agony and terror. At no time has the earth been so soaked with blood.” Heschel's extraordinary life's witness, his whole body of work, traverses precisely this anthropological and theological knife's edge: The mark of Cain in the face of man has come to overshadow the likeness of God. Where is God? Or better, Who is God? in relation to the rapacious misuse and idolatrous distortion of human freedom? Or simply, Is God?


2004 ◽  
Vol 8 (4) ◽  
pp. 239-243 ◽  
Author(s):  
Kenneth J. Craddock ◽  
Jaggi Rao ◽  
Gilles J. Lauzon ◽  
Victor A. Tron

Background: Ultraviolet (UV) radiation is known to be an important etiologic agent in the development of skin cancer. Keratoacanthoma is an unusual, well-described cutaneous neoplasm that resembes squamous cell carcinoma but spontaneously resolves. Rarely, multiple keratoacanthomas may develop. Objective We present a case of multiple keratoacanthomas in a patient with psoriasis who had received UVB phototherapy. These lesions were hyperkeratotic papules, many of which spontaneously resolved and demonstrated the histologic characteristics of keratoacanthoma. Conclusion: We believe that UV radiation is the most likely etiologic factor in this patient's development of multiple keratoacanthomas. We wish to bring to the attention of clinicians this unusual adverse effect of UV treatment.


2011 ◽  
Vol 209 (3) ◽  
pp. 443-454
Author(s):  
M. Tatalias ◽  
C. J. Bockisch ◽  
G. Bertolini ◽  
D. Straumann ◽  
A. Palla

1996 ◽  
Vol 68 (9) ◽  
pp. 1749-1756 ◽  
Author(s):  
M. J. Molina

The chlorofluorocarbons (CFCs) are industrialchemicals used as solvents, refrigerants, plastic foam blowing agents,etc. These compounds are eventually released to the environment; theyslowly drift into the stratosphere, where they decompose, initiatinga catalytic process involving chlorine free radicals and leading toozone destruction. The stratospheric ozone layer is important for theearth's energy budget, and it shields the surface of the earth fromultraviolet radiation from the sun. Very significant depletion of theozone layer has been observed in the spring months over Antarctica duringthe last 10-15 years. Laboratory experiments, model calculations andfield measurements, which include several aircraft expeditions, haveyielded a wealth of information which clearly points to the CFCs asthe main cause of this depletion.


2017 ◽  
Vol 10 (1) ◽  
pp. 271-319 ◽  
Author(s):  
Thomas Gasser ◽  
Philippe Ciais ◽  
Olivier Boucher ◽  
Yann Quilcaille ◽  
Maxime Tortora ◽  
...  

Abstract. This paper provides a comprehensive description of OSCAR v2.2, a simple Earth system model. The general philosophy of development is first explained, followed by a complete description of the model's drivers and various modules. All components of the Earth system necessary to simulate future climate change are represented in the model: the oceanic and terrestrial carbon cycles – including a book-keeping module to endogenously estimate land-use change emissions – so as to simulate the change in atmospheric carbon dioxide; the tropospheric chemistry and the natural wetlands, to simulate that of methane; the stratospheric chemistry, for nitrous oxide; 37 halogenated compounds; changing tropospheric and stratospheric ozone; the direct and indirect effects of aerosols; changes in surface albedo caused by black carbon deposition on snow and land-cover change; and the global and regional response of climate – in terms of temperature and precipitation – to all these climate forcers. Following the probabilistic framework of the model, an ensemble of simulations is made over the historical period (1750–2010). We show that the model performs well in reproducing observed past changes in the Earth system such as increased atmospheric concentration of greenhouse gases or increased global mean surface temperature.


Blood ◽  
2002 ◽  
Vol 100 (4) ◽  
pp. 1233-1239 ◽  
Author(s):  
Joseph G. Jurcic ◽  
Steven M. Larson ◽  
George Sgouros ◽  
Michael R. McDevitt ◽  
Ronald D. Finn ◽  
...  

Unlike β particle–emitting isotopes, α emitters can selectively kill individual cancer cells with a single atomic decay. HuM195, a humanized anti-CD33 monoclonal antibody, specifically targets myeloid leukemia cells and has activity against minimal disease. When labeled with the β-emitters 131I and 90Y, HuM195 can eliminate large leukemic burdens in patients, but it produces prolonged myelosuppression requiring hematopoietic stem cell transplantation at high doses. To enhance the potency of native HuM195 yet avoid the nonspecific cytotoxicity of β-emitting constructs, the α-emitting isotope 213Bi was conjugated to HuM195. Eighteen patients with relapsed and refractory acute myelogenous leukemia or chronic myelomonocytic leukemia were treated with 10.36 to 37.0 MBq/kg 213Bi-HuM195. No significant extramedullary toxicity was seen. All 17 evaluable patients developed myelosuppression, with a median time to recovery of 22 days. Nearly all the 213Bi-HuM195 rapidly localized to and was retained in areas of leukemic involvement, including the bone marrow, liver, and spleen. Absorbed dose ratios between these sites and the whole body were 1000-fold greater than those seen with β-emitting constructs in this antigen system and patient population. Fourteen (93%) of 15 evaluable patients had reductions in circulating blasts, and 14 (78%) of 18 patients had reductions in the percentage of bone marrow blasts. This study demonstrates the safety, feasibility, and antileukemic effects of 213Bi-HuM195, and it is the first proof-of-concept for systemic targeted α particle immunotherapy in humans.


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