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Background Acne vulgaris is a common condition that occurs in all skin types. Postinflammatory hyperpigmentation ( PIH) is often associated with acne in patients of darker skin types, making it a common complaint in dermatology offices. Despite this, there is limited understanding of and effective treatment options for PIH. Objectives The study objective was to validate an in vivo model for PIH and to compare the clinical, histological and spectroscopic characteristics of artificially induced PIH and acne-induced PIH. Methods A nonblinded, nonrandomized pilot study was performed. Thirty subjects served as their own control in which four sites treated with 35% trichloroacetic acid ( TCA) solution and four truncal acne pustules were followed for 8 weeks and were evaluated clinically and histologically, and by colorimetry and spectroscopy. Results The initial phases of inflammation between TCA- and acne-induced PIH differ. However, clinical evaluations were similar on and after day 14. Acne- and TCA-induced lesions were clinically, histologically and spectroscopically indistinguishable at day 28. Conclusions Clinical, spectroscopic and histological similarities of acne-induced and TCA-induced PIH at day 28 suggest that TCA-induced PIH can be a reproducible model for the study of acne-induced PIH. [ABSTRACT FROM AUTHOR]

ABSTRACT RECQ DNA helicases play critical roles in maintaining genomic stability, but their role in development has been less well studied. Rothmund-Thomson syndrome, RAPADILINO, and Baller-Gerold syndrome are rare genetic disorders caused by mutations in the RECQL4 gene. These patients have significant skeletal developmental abnormalities including radial ray, limb and craniofacial defects. To investigate the role of Recql4 in the developing skeletal system, we generated Recql4 conditional knockout mice targeting the skeletal lineage. Inactivation of Recql4 using the Prx1-Cre transgene led to limb abnormalities and craniosynostosis mimicking the major bone findings in human RECQL4 patients. These Prx1-Cre+;Recql4fl/fl mice as well as Col2a1-Cre+;Recql4fl/fl mice exhibited growth plate defects and an increased p53 response in affected tissues. Inactivation of Trp53 in these Recql4 mutants resulted in genetic rescue of the skeletal phenotypes, indicating an in vivo interaction between Recql4 and Trp53, and p53 activation as an underlying mechanism for the developmental bone abnormalities in RECQL4 disorders. Our findings show that RECQL4 is critical for skeletal development by modulating p53 activity in vivo. © 2015 American Society for Bone and Mineral Research [ABSTRACT FROM AUTHOR]

The article discusses a case of syndromic inherited poikiloderma due to a de novo mutation in FAM111B gene.

RECQL4, a RecQ helicase deficient in Rothmund-Thomsons syndrome, is a multifunctional participant of DNA metabolism. Here, we show that RECQL4 interacts with the Ku complex of DNA-PK and participates in DNA repair via NHEJ.RECQL4, a member of the RecQ helicase family, is a multifunctional participant in DNA metabolism. RECQL4 protein participates in several functions both in the nucleus and in the cytoplasm of the cell, and mutations in human RECQL4 are associated with three genetic disorders: Rothmund-Thomson, RAPADILINO and Baller-Gerold syndromes. We previously reported that RECQL4 is recruited to laser-induced DNA double-strand breaks (DSB). Here, we have characterized the functional roles of RECQL4 in the non-homologous end joining (NHEJ) pathway of DSB repair. In an in vitro NHEJ assay that depends on the activity of DNA-dependent protein kinase (DNA-PK), extracts from RECQL4 knockdown cells display reduced end-joining activity on DNA substrates with cohesive and non-cohesive ends. Depletion of RECQL4 also reduced the end joining activity on a GFP reporter plasmid in vivo. Knockdown of RECQL4 increased the sensitivity of cells to γ-irradiation and resulted in accumulation of 53BP1 foci after irradiation, indicating defects in the processing of DSB. We find that RECQL4 interacts with the Ku70/Ku80 heterodimer, part of the DNA-PK complex, via its N-terminal domain. Further, RECQL4 stimulates higher order DNA binding of Ku70/Ku80 to a blunt end DNA substrate. Taken together, these results implicate that RECQL4 participates in the NHEJ pathway of DSB repair via a functional interaction with the Ku70/Ku80 complex. This is the first study to provide both in vitro and in vivo evidence for a role of a RecQ helicase in NHEJ. [ABSTRACT FROM AUTHOR]

Kindler syndrome ( KS) is an inherited dermatosis linked to the FERMT1 gene, and is characterized clinically by trauma-induced acral skin blisters in infancy and childhood, photosensitivity, and progressive poikiloderma. We report a case of KS in a 7-year-old Indian girl with severe mucosal involvement of the oral cavity and genitourinary tract. Mutation analysis in the girl showed a homozygous FERMT1 mutation, c.862C>T, p.R288*. The clinical manifestations in patients with KS show significant inter individual variation, even with the same type of mutations and within members of the same family. Our case highlights the role of environmental modifiers in regulating the clinical features of KS. [ABSTRACT FROM AUTHOR]

Human RECQL4 protein was expressed in insect cells using a baculovirus protein expression system and it was purified to near homogeneity. The protein sedimented at a position between catalase (230 kDa) and ferritin (440 kDa) in glycerol gradient centrifugation, suggesting that it forms homo-multimers. Activity to displace annealed 17-mer oligonucleotide in the presence of ATP was co-sedimented with hRECQL4 protein. In ion-exchange chromatography, both DNA helicase activity and single-stranded DNA-dependent ATPase activity were co-eluted with hRECQL4 protein. The requirements of ATP and Mg for the helicase activity were different from those for the ATPase activity. The data suggest that the helicase migrates on single-stranded DNA in a 3′–5′ direction. These results suggest that the hRECQL4 protein exhibits DNA helicase activity. [ABSTRACT FROM PUBLISHER]

The article presents information on the demographic and clinical differences between unilateral and bilateral forms of naevoid telangiectasia. Unilateral naevoid telangiectasia (UNT) is described by telangiectasia spread in a unilateral, dermatomal pattern, specifically on the upper trunk and extremities.

The article presents a case study of a 21-year-old woman was brought in to the department of internal medicine of Kuwait University Hospital in Yemen in 2006 for the treatment of pleural effusion. It mentions that the patient was diagnosed with Rothmund-Thomson syndrome (RTS), a rare genetic disorder, based on the examination of her medical history. The patient exhibited a unique combination of features including atypical plantar keratodermas, clinodactyly and pachyonychia.

Linked Article:Isedeh et al. Br J Dermatol 2016; 174:862–868. [ABSTRACT FROM AUTHOR]