From bedside to genetic analysis: New insights into pathophysiology of melanoma, basal cell carcinoma, and other cancers.

Objective: Patients with myotonic muscular dystrophy (MMD) were observed to have numerous basal cell carcinoma (BCC) and abnormal dysplastic nevi (DN) on non-sun exposed skin. Simultaneously a large study published in the Journal of American Medical Association (JAMA) illustrated that patients with MMD have "overall" an increased risk for cancer development. Based on these findings, this author in 2010 postulated that dysregulation of RNA binding proteins (RBP), responsible for clinical manifestations of MMD, is also responsible for the development of BCC and melanoma.

Skin ultrasonography and magnetic resonance; new clinical applications and instrumentation.

Background: Technological advances in skin ultrasonography and magnetic resonance are discussed.

Methods: Literature review.

Results: 40 publications cited.

Proposed guidelines for appropriate utilization of superficial radiation therapy in management of skin cancers. Zemtsov-Cognetta criteria.

Objective: To develop appropriate use criteria (AUC) for the treatment of basal cell and squamous cell carcinoma by superficial radiation therapy (SRT) technique.

Material And Methods: Delphi-type discussion of the experts.

Results: Presented in Figure 1.

Atom-transfer radical addition of fluoroalkyl bromides to alkenes via a photoredox/copper catalytic system.

A method for the addition of fluorinated alkyl bromides to alkenes is described. The reaction proceeds under visible light irradiation in the presence of two catalysts: Ir(ppy) and N-heterocyclic carbene ligated copper bromide (IMesCuBr). The role of the iridium photocatalyst is to generate the fluoralkyl radical, while the copper promotes formation of the carbon-bromine bond.

Photoredox Reaction of 2-Mercaptothiazolinium Salts with Silyl Enol Ethers.

A method for the generation of free radicals from thiazolinium salts upon photocatalytic reduction is described. The thiazolinium salts are generated by treatment with methyl triflate of 2-mercaptothiazolines, which can be readily obtained from alkyl bromides and tosylates via a nucleophilic substitution reaction or by hydrothiolation of alkenes. Silyl enol ethers were used to trap the radicals, furnishing ketones after successive single-electron oxidation and elimination of the silyl cation.

Lichenoid Reaction Pattern with Pseudoepitheliomatous Hyperplasia - A Rare Tattoo Reaction: A Case Report and Review of the Literature.

Pseudoepitheliomatous hyperplasia is a benign histologic reaction pattern that in rare cases can occur shortly after a tattooing procedure. We describe a case of pseudoepitheliomatous hyperplasia in two tattoos on the same patient 1 year after filling with the same batch of red ink.

Nucleophilic Difluoromethylation Using (Bromodifluoromethyl)trimethylsilane.

A combination of (bromodifluoromethyl)trimethylsilane (Me3SiCF2Br), triphenylphosphine, and DMPU serves as a source of difluorinated phosphorus ylide Ph3P═CF2 under mild conditions. The system was used to effect nucleophilic difluoromethylation of ketones and nitro alkenes. The reaction efficiency is believed to be associated with Lewis acidic activation of the substrates by a silylium species formed upon generation of the phosphorus ylide.

Coupling of α,α-difluoro-substituted organozinc reagents with 1-bromoalkynes.

α,α-Difluoro-substituted organozinc reagents generated from conventional organozinc compounds and difluorocarbene couple with 1-bromoalkynes affording gem-difluorinated alkynes. The cross-coupling proceeds in the presence of catalytic amounts of copper iodide in dimethylformamide under ligand-free conditions.

Difluoromethylene phosphabetaine as an equivalent of difluoromethyl carbanion.

A method for nucleophilic difluoromethylation of reactive Michael acceptors, aldehydes, and azomethines is described. The reaction is performed using the readily available and air-stable reagent difluoromethylene phosphabetaine. The process involves interaction of an electrophilic substrate with in situ generated difluorinated phosphonium ylide followed by hydrolysis of the carbon-phosphorus bond under mild conditions.

Geminal silicon/zinc reagent as an equivalent of difluoromethylene bis-carbanion.

A new difluorinated reagent, [difluoro(trimethylsilyl)methyl]zinc bromide, bearing C-Zn and C-Si bonds is described. The reagent is conveniently prepared by cobalt-catalyzed halogen/zinc exchange. It can be coupled with two different C-electrophiles in a stepwise manner (with allylic halides for C-Zn bond and aldehydes for C-Si bond) affording products containing a difluoromethylene fragment.

Copper-catalyzed allylation of α,α-difluoro-substituted organozinc reagents.

A method for the coupling of organozinc reagents, difluorocarbene, and allylic electrophiles is described. The reaction involves insertion of difluorocarbene into the carbon-zinc bond followed by copper-catalyzed allylic substitution.

Reactions of difluorocarbene with organozinc reagents.

Reactions of difluorocarbene with benzyl and alkylzinc halides leading to fluorinated organozinc species have been described. The generated α-difluorinated organozinc reagents are reasonably stable in solution and can be quenched with external electrophiles (iodine, bromine, proton), affording compounds containing the CF(2) fragment.

Porphyria cutanea tarda presenting as scleroderma.

Sclerodermatous skin changes were observed in a patient with porphyria cutanea tarda (PCT) who initially was diagnosed as having progressive systemic sclerosis (PSS). In extremely rare circumstances, patients with PCT initially are misdiagnosed as having generalized morphea, or PSS, because they lack the typical skin findings of PCT, such as blisters, skin fragility, scarring on the dorsal aspects of the hands, and facial hypertrichosis. However, even in cases of PCT that clinically mimic and are misdiagnosed as PSS, the sclerodermatous skin changes primarily occur in v-shaped areas of the neck.

Association between basal, squamous cell carcinomas, dysplastic nevi and myotonic muscular dystrophy indicates an important role of RNA-binding proteins in development of human skin cancer.

Myotonic muscular dystrophy (MMD) is caused by an abnormal function of RNA-binding proteins (RBP) resulting in DNA spliceopathy. A case of a patient, with MMD multiple basal and squamous cell carcinomas and dysplastic nevi, is described. The association between MMD and non-melanoma skin cancer has been reported before; however, this association was described before the genetic defect of myotonic dystrophy has been fully elucidated.

Topically applied growth factors change skin cytoplasmic creatine kinase activity and distribution and produce abnormal keratinocyte differentiation in murine skin.

Background/purpose: The skin has a functional and active phosphocreatine (PCR)/creatine kinase (CPK) system that regenerates adenosine triphosphate energy reserves during periods of ischemia. The objective of this study was to evaluate how topically applied growth factors affect CPK activity and distribution, and what histological changes growth factors induce in murine skin.

Methods: Epidermal growth factor (EGF), transforming growth factor alpha (TGF-alpha) and suramin (growth factor inhibitor) were applied to murine skin for nine days before mice were sacrificed and CPK level and distributions were measured.

Skin phosphocreatine.

Background/purpose: The skin has the unique ability to survive ischemia associated with skin grafts, flaps and hair transplantation procedures. Spectroscopic data later confirmed by chromatography, immunohistochemistry and molecular biology techniques identified the presence of large quantities of phosphocreatine in human skin. Phosphocreatine molecules regenerate ATP cellular reserves during ischemia.

Euthyroid pretibial myxedema.

Objective: To describe a case of biopsy-proven pretibial myxedema in a man with normal thyroid function.

Methods: We present the pertinent clinical and laboratory data for the current case and review previously published information on pretibial myxedema.

Results: Our patient, a 53-year-old man, had the characteristic lesions of pretibial myxedema on the anterolateral aspects of his calves.