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The Journal of Clinical and Aesthetic... Jun 2023Phototherapy has gained popularity in the recent decades for the treatment of various immune-mediated dermatological conditions since it is more-cost effective and less...
Phototherapy has gained popularity in the recent decades for the treatment of various immune-mediated dermatological conditions since it is more-cost effective and less toxic compared to systemic therapies. This systematic review aims to inform dermatology providers of the risks and benefits of phototherapy, especially in patients at risk for malignancies. Ionizing energy from phototherapy results in DNA photolesions, namely of cyclobutane pyrimidine dimers (CPDs) and 6-4 photoproducts (6-4PPs). Without adequate repair, these mutations increase the risk for carcinogenesis. Additionally, phototherapy can also indirectly cause DNA damage through the formation of reactive oxygen species (ROS), which damage of several structural and functional proteins and DNA. When choosing a phototherapy modality, it also important to take into consideration the side effect profiles associated with each modality. For instance, a 10-fold higher dose of NB-UVB is required to produce a similar amount of CPDs compared with BB-UVB. Patients who undergo UVA with psoralen (PUVA) can be susceptible to developing skin malignancies up to 25 years after receiving their last treatment. It would behoove providers to consider optimal radiation dosage given each patients' level of skin pigmentation and potential for photoadaptation. Additionally, there are measures have been proposed to minimize deleterious skin changes, such as a 42-degree Celsius heat treatment using a 308nm excimer laser prior to UVB phototherapy and low frequency, low intensity electromagnetic fields along with UVB. However, as performing routine skin exams, remain paramount in the prevention of phototherapy-induced neoplasia.
PubMed: 37361361
DOI: No ID Found -
International Journal of Health Sciences 2020The study aimed to review the literature on the use of ultraviolet-C (UV-C) sterilization to assess its clinical efficacy in reducing risk and transmission of nosocomial... (Review)
Review
OBJECTIVES
The study aimed to review the literature on the use of ultraviolet-C (UV-C) sterilization to assess its clinical efficacy in reducing risk and transmission of nosocomial infections as well as its associated health safety or hazards.
METHODS
Four main search engines were used to identify potential studies which included: (1) Google Scholar, (2) ScienceDirect, (3) PubMed, and (4) Cochrane. Studies in English and published from 2010 to 2020 were considered. Studies on efficacy were limited to those in unseeded hospital environments, examining environmental disinfection, and with true experimental, randomized controlled trial, or quasi-experimental study designs. No additional criterion was used for safety studies due to the scarcity of literature. In the end, a total of 17 studies were selected. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Risk of bias assessment and manual data extraction and tabulation were done.
RESULTS
Twelve eligible efficacy studies were identified together with five safety studies. It was found that UV-C irradiation had positive results when used as an adjunct for existing cleaning protocols. The germicidal effect of UV-C is potent against microorganisms including viruses, methicillin-resistant , and vancomycin-resistant enterococci. Safety study results showed dermal effects of UV-C exposure including DNA lesions, formation of cyclobutane pyrimidine dimers in cells, and effects on the skin's stratum corneum.
CONCLUSION
It was found that UV-C can be utilized as an adjunct to terminal manual cleaning because of its efficacy as a germicidal agent. Further studies must still be done to exact a standard for safe exposure dose, especially for 222 nm germicidal lamps. Direct evidence is needed for any targeted implementation of UV-C during Coronavirus Disease 2019 (COVID-19) pandemic.
PubMed: 33192232
DOI: No ID Found -
Gastroenterology Jan 2017High-throughput sequencing analysis has accelerated searches for genes associated with risk for colorectal cancer (CRC); germline mutations in NTHL1, RPS20, FANCM, FAN1,... (Review)
Review
High-throughput sequencing analysis has accelerated searches for genes associated with risk for colorectal cancer (CRC); germline mutations in NTHL1, RPS20, FANCM, FAN1, TP53, BUB1, BUB3, LRP6, and PTPN12 have been recently proposed to increase CRC risk. We attempted to validate the association between variants in these genes and development of CRC in a systematic review of 11 publications, using sequence data from 863 familial CRC cases and 1604 individuals without CRC (controls). All cases were diagnosed at an age of 55 years or younger and did not carry mutations in an established CRC predisposition gene. We found sufficient evidence for NTHL1 to be considered a CRC predisposition gene-members of 3 unrelated Dutch families were homozygous for inactivating p.Gln90Ter mutations; a Canadian woman with polyposis, CRC, and multiple tumors was reported to be heterozygous for the inactivating NTHL1 p.Gln90Ter/c.709+1G>A mutations; and a man with polyposis was reported to carry p.Gln90Ter/p.Gln287Ter; whereas no inactivating homozygous or compound heterozygous mutations were detected in controls. Variants that disrupted RPS20 were detected in a Finnish family with early-onset CRC (p.Val50SerfsTer23), a 39-year old individual with metachronous CRC (p.Leu61GlufsTer11 mutation), and a 41-year-old individual with CRC (missense p.Val54Leu), but not in controls. We therefore found published evidence to support the association between variants in NTHL1 and RPS20 with CRC, but not of other recently reported CRC susceptibility variants. We urge the research community to adopt rigorous statistical and biological approaches coupled with independent replication before making claims of pathogenicity.
Topics: Adenomatous Polyposis Coli; Colorectal Neoplasms; Deoxyribonuclease (Pyrimidine Dimer); Genetic Predisposition to Disease; Germ-Line Mutation; Humans; Ribosomal Proteins
PubMed: 27713038
DOI: 10.1053/j.gastro.2016.09.041 -
Photodermatology, Photoimmunology &... Nov 2020DNA damage is one of the main factors responsible for photoageing and is predominantly attributed to ultraviolet irradiation (UV-R). Photoprotection by conventional...
BACKGROUND
DNA damage is one of the main factors responsible for photoageing and is predominantly attributed to ultraviolet irradiation (UV-R). Photoprotection by conventional sunscreens is exclusively prophylactic, and of no value, once DNA damage has occurred. As a result, the demand for DNA repair mechanisms inhibiting, reversing or delaying the pathologic events in UV-exposed skin has sparked research on anti-photoageing and strategies to improve the effect of conventional sunscreens. This review provides an overview of recent developments in DNA repair enzymes used in sunscreens and their impact on photoageing.
METHODS
A systematic review of the literature, up to March 2019, was conducted using the electronic databases, PubMed and Web of Science. Quality assessment was carried out using the Newcastle-Ottawa scale (NOS) to ensure inclusion of adequate quality studies only (NOS > 5).
RESULTS
Out of the 352 publications, 52 were considered relevant to the key question and included in the present review. Two major enzymes were found to play a major role in DNA damage repair in sunscreens: photolyase and T4 endonuclease V. These enzymes are capable of identifying and removing UV-R-induced dimeric photoproducts. Clinical studies revealed that sunscreens with liposome-encapsulated types of photolyase and/or T4 endonuclease V can enhance these repair mechanisms.
CONCLUSION
There is a lack of randomized controlled trials demonstrating the efficacy of DNA repair enzymes on photoageing, or a superiority of sunscreens with DNA repair enzymes compared to conventional sunscreens. Further studies are mandatory to further reveal pathogenic factors of photoageing and possible therapeutic strategies against it.
Topics: Animals; DNA Damage; DNA Repair; Deoxyribodipyrimidine Photo-Lyase; Deoxyribonuclease (Pyrimidine Dimer); Humans; Skin Aging; Sunscreening Agents; Ultraviolet Rays; Viral Proteins
PubMed: 32772409
DOI: 10.1111/phpp.12597