مطالب توسط

Ultraviolet Light in Human Health, Diseases and Environment

ABSTRACT

The use of ultraviolet (UV) light, for the treatment of skin conditions ,dates back to the early 1900s. It is well known that sunlight can be of therapeutic value, but it can also lead to deleterious effects such as burning and carcinogenesis. Extensive research has expanded our understanding of UV radiation and its effects in human systems and has led to the development of man-made UV sources that are more precise, safer, and more effective for the treatment of wide variety of dermatologic conditions.

INTRODUCTION

Ultraviolet (UV) light is an electromagnetic radiation varying in its wavelength from 100– 400 nm. At one side of this band is visible light which is longer than 400 nm starting with blue light and on the other is x-rays which is of shorter length than 100 nm. Two major sources of UV lights are: the sun and the man-made UV lamps. In earlier days the solar UV light, ranging from 180–400 nm, was divided in three basic types: UVA, 320–400 nm, UVB 290–320 nm and UVC 180–290 nm, but now is classifed into narrowband UVB of 311–313 nm, man-made Excimer laser of 380 nm, UVA2 of 320–340 nm and UVA 340–400 nm. Ultraviolet light has played a major role in biological research and according to (PubMed, November 2016) 82,617 research papers have been published involving UV light. UV light was discovered in 1801 by German Physicist, Johann Wilhelm Ritter. The discovery was based on his observation that there exist invisible rays of light beyond the violet end of the visible spectra, capable of darkening silver chloride-soaked paper more rapidly than the violet light itself, termed “Oxidizing rays”. Soon after its discovery, its name was changed to “chemical rays” but fnally these names were dropped in favor of ultraviolet rays. Then, in 1878 the effect of short-wavelength UV light on bacteria was discovered which was used in sterilization. The earliest record (PubMed, June 2016) of the role of UV light on a biological system is of 1903, when this light was used to treat Lupus in humans . Then, in 1922 the importance of UV light on living organisms was shown on Drosophila; a detailed monograph can be seen published in 1928, implicating the importance and application of UV light in therapeutics, . Although the exact type of UV light used is unknown, it is likely that short- wavelength UVC light was used in the experiments.

چکیده

استفاده از نور ماوراء بنفش (UV) برای درمان بیماری های پوستی به اوایل دهه 1900 باز می گردد. به خوبی شناخته شده است که نور خورشید می تواند از ارزش درمانی برخوردار باشد اما می تواند منجر به اثرات زیان آور مانند سوختن و سرطان زایی شود. تحقیقات گسترده ما درک ما از اشعه ماوراء بنفش و اثرات آن در سیستم های انسانی را گسترش داده است و منجر به توسعه منابع منفرد UV شده است که دقیق تر، ایمن تر و موثرتر برای درمان انواع مختلف بیماری های پوستی هستند.

مقدمه

نور UV (اشعه ماوراء بنفش) یک تابش الکترومغناطیسی است که در طول موج آن از 100 تا 400 نانومتر متغیر است. در یک طرف این باند نور قابل رویت است که طول آن بیش از 400 نانومتر است که از نور آبی شروع می شود و از سوی دیگر اشعه ایکس است که طول آن کمتر از 100 نانومتر است. دو منبع عمده از چراغ های UV عبارتند از: خورشید و اشعه ماوراء بنفش انسان. در روزهای اولیه، نور UV خورشیدی که از 180 تا 400 نانومتر بود، به سه نوع اساسی تقسیم شد: UVA، 320-400 نانومتر، UVB 290-320 نانومتر و UVC 180-290 نانومتر، اما اکنون به UVB باند باند 311 تقسیم شده است -313 نانومتر، لیزر اکسایمر ساخته شده از ماده 380 نانومتر، UVA2 320-340 نانومتر و UVA 340-400 نانومتر. نور نورفشانی نقش عمده ای در تحقیقات بیولوژیک ایفا کرده است و بر اساس (PubMed، نوامبر 2016) 82،617 مقاله پژوهشی منتشر شده است که شامل نور UV است. نور UV در سال 1801 توسط فیزیکدان آلمانی، یوهان ویلهلم ریتر کشف شد. این کشف بر اساس مشاهدۀ او بود که پرتوهای نامرئی نور بیش از انتهای بنفش طیف های قابل مشاهده وجود دارد که می تواند کاغذی را که به رنگ مایع کلرید نقره ای تیره شده است تیره تر کند، به همین ترتیب نور خود را بنام “اشعه اکسید کننده” نامید. به زودی پس از کشف آن، نام آن به “اشعه های شیمیایی” تغییر یافت اما این نام ها به نفع اشعه های ماورای بنفش افتاد. سپس، در سال 1878، اثر UV نور کوتاه مدت بر روی باکتری ها کشف شد که در عقیم سازی استفاده شد. اولین ضبط (PubMed، ژوئن 2016) از نقش نور UV بر سیستم بیولوژیکی، سال 1903 است، زمانی که این نور برای درمان لوپوس در انسان استفاده می شود. سپس، در سال 1922 اهمیت نور UV بر موجودات زنده بر روی Drosophila نشان داده شد؛ یک نقاشی دقیق را می توان در سال 1928 منتشر کرد، که اهمیت و کاربرد نور UV را در درمان دارد. اگر چه نوع دقیق نور UV استفاده شده ناشناخته است، احتمال دارد نور نور UVC کوتاه مدت در آزمایشات استفاده شود.

Year: 2016

Publisher: SPRINGER

By : Shamim I. Ahmad

File Information: English Language/ 367 Page / size: 6.42 MB

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سال : 1395

ناشر : SPRINGER

کاری از : شامیم احمد

اطلاعات فایل : زبان انگلیسی / 367 صفحه / حجم : MB 6.42

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The use of ultraviolet (UV) light, for the treatment of skin conditions ,dates back to the early 1900s. It is well known that sunlight can be of therapeutic value, but it can also lead to deleterious effects such as burning and carcinogenesis. Extensive research has expanded our understanding of UV radiation and its effects in human systems and has led to the development of man-made UV sources that are more precise, safer, and more effective for the treatment of wide variety of dermatologic conditions.

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